Identifying the determinants of childhood immunization in the Philippines

Association between achieving adequate antenatal care and health-seeking behaviors: A study of Demographic and Health Surveys in 47 low- and middle-income countries

BACKGROUND

Antenatal care (ANC) is essential for ensuring the well-being of pregnant women and their fetuses. This study models the association between achieving adequate ANC and various health and health-seeking indicators across wealth quintiles in low- and middle-income countries (LMICs).

METHODS AND FINDINGS

We analyzed data from 638,265 women across 47 LMICs using available Demographic and Health Surveys from 2010 to 2022. Via multilevel logistic regression analyses adjusted for a series of confounding variables and country and wealth quintile fixed effects, we estimated the projected impact of achieving adequate ANC utilization and quality on a series of health and health care indicators: facility birth, postnatal care, childhood immunizations, and childhood stunting and wasting. Achieving adequate levels of ANC utilization and quality (defined as at least 4 visits, blood pressure monitoring, and blood and urine testing) was positively associated with health-seeking behavior across the majority of countries. The strongest association was observed for facility birth, followed by postnatal care and child immunization. The strength of the associations varied across countries and wealth quintiles, with more significant ones observed in countries with lower baseline ANC utilization levels and among the lower wealth quintiles. The associations of ANC with childhood stunting and wasting were notably less statistically significant compared to other indicators. Despite rigorous adjustments for potential confounders, a limitation to the methodology is that it is possible that unobserved variables may still impact outcomes.

CONCLUSIONS

Strengthening ANC is associated with improved use of other health care in LMICs. ANC could serve as a critical platform for improving health outcomes for mothers and their children, emphasizing its importance beyond direct impact on maternal and neonatal mortality.

Community Engagement in Vaccination Promotion: Systematic Review and Meta-Analysis

BACKGROUND

Community engagement plays a vital role in global immunization strategies, offering the potential to overcome vaccination hesitancy and enhance vaccination confidence. Although there is significant backing for community engagement in health promotion, the evidence supporting its effectiveness in vaccination promotion is fragmented and of uncertain quality.

OBJECTIVE

This review aims to systematically examine the effectiveness of different contents and extent of community engagement for promoting vaccination rates.

METHODS

This study was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A comprehensive and exhaustive literature search was performed in 4 English databases (PubMed, Embase, Web of Science, and Cochrane Library) and 2 Chinese databases (CNKI and Wan Fang) to identify all possible articles. Original research articles applying an experimental study design that investigated the effectiveness of community engagement in vaccination promotion were eligible for inclusion. Two reviewers independently performed the literature search, study selection, quality assessment, and data extraction. Discrepancies were resolved through discussion, with the arbitration of a third reviewer where necessary.

RESULTS

A total of 20 articles out of 11,404 records from 2006 to 2021 were retrieved. The studies used various designs: 12 applied single-group pre-post study designs, 5 were cluster randomized controlled trials (RCTs), and 3 were non-RCTs. These studies targeted multiple vaccines, with 8 focusing on children's immunization, 8 on human papillomavirus vaccine, 3 on hepatitis B virus vaccine, and 1 on COVID-19 vaccine. The meta-analysis revealed significant increases in vaccination rates both in pre-post comparison (rate difference [RD] 0.34, 95% CI 0.21-0.47, I2=99.9%, P<.001) and between-group comparison (RD 0.18, 95% CI 0.07-0.29, I2=98.4%, P<.001). The meta-analysis revealed that participant recruitment had the largest effect size (RD 0.51, 95% CI 0.36-0.67, I2=99.9%, P<.001), followed by intervention development (RD 0.36, 95% CI 0.23-0.50, I2=100.0%, P<.001), intervention implementation (RD 0.35, 95% CI 0.22-0.47, I2=99.8%, P<.001), and data collection (RD 0.34, 95% CI 0.19-0.50, I2=99.8%, P<.001). The meta-analysis indicated that high community engagement extent yielded the largest effect size (RD 0.49, 95% CI 0.17-0.82, I2=100.0%, P<.001), followed by moderate community engagement extent (RD 0.45, 95% CI 0.33-0.58, I2=99.6%, P<.001) and low community engagement extent (RD 0.15, 95% CI 0.05-0.25, I2=99.2%, P<.001). The meta-analysis revealed that "health service support" demonstrated the largest effect sizes (RD 0.45, 95% CI 0.25-0.65, I2=99.9%, P<.001), followed by "health education and discussion" (RD 0.39, 95% CI 0.20-0.58, I2=99.7%, P<.001), "follow-up and reminder" (RD 0.33, 95% CI 0.23-0.42, I2=99.3%, P<.001), and "social marketing campaigns and community mobilization" (RD 0.24, 95% CI 0.06-0.41, I2=99.9%, P<.001).

CONCLUSIONS

The results of this meta-analysis supported the effectiveness of community engagement in vaccination promotion with variations in terms of engagement contents and extent. Community engagement required a "fit-for-purpose" approach rather than a "one-size-fits-all" approach to maximize the effectiveness of vaccine promotion.

TRIAL REGISTRATION

PROSPERO CRD42022339081; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=339081.

Child immunization status according to number of siblings and birth order in 85 low- and middle-income countries: a cross-sectional study

Background

Identification of unvaccinated children is important for preventing deaths due to infections. Number of siblings and birth order have been postulated as risk factors for zero-dose prevalence.

Methods

We analysed nationally representative cross-sectional surveys from 85 low and middle-income countries (2010-2020) with information on immunisation status of children aged 12-35 months. Zero-dose prevalence was defined as the failure to receive any doses of DPT (diphtheria-pertussis-tetanus) vaccine. We examined associations with birth order and the number of siblings, adjusting for child's sex, maternal age and education, household wealth quintiles and place of residence. Poisson regression was used to calculate zero-dose prevalence ratios.

Findings

We studied 375,548 children, of whom 13.7% (n = 51,450) were classified as zero-dose. Prevalence increased monotonically with birth order and with the number of siblings, with prevalence increasing from 11.0% for firstborn children to 17.1% for birth order 5 or higher, and from 10.5% for children with no siblings to 17.2% for those with four or more siblings. Adjustment for confounders attenuated but did not eliminate these associations. The number of siblings remained as a strong risk factor when adjusted for confounders and birth order, but the reverse was not observed. Among children with the same number of siblings, there was no clear pattern in zero-dose prevalence by birth order; for instance, among children with two siblings, the prevalence was 13.0%, 14.7%, and 13.3% for firstborn, second, and third-born, respectively. Similar results were observed for girls and boys. 9513 families had two children aged 12-35 months. When the younger sibling was unvaccinated, 61.9% of the older siblings were also unvaccinated. On the other hand, when the younger sibling was vaccinated, only 5.9% of the older siblings were unvaccinated.

Interpretation

The number of siblings is a better predictor than birth order in identifying children to be targeted by immunization campaigns. Zero-dose children tend to be clustered within families.

Funding

Gavi, the Vaccine Alliance.

Changes in immunization coverage and contributing factors among children aged 12-23 months from 2000 to 2019, Ethiopia: Multivariate decomposition analysis

BACKGROUND

Immunization has been promoted as a global strategy aimed at improving child survival. The World Health Organization strives to make immunization services available to everyone, everywhere to save over 50 million lives by 2030. Monitoring the change and identifying the factors contributing to the change in immunization coverage over time and across the nations is imperative for continuing global success in increasing immunization coverage. In this study, we examined the changes and factors that contributed to the change in full immunization coverage over time in Ethiopia (2000 to 2019).

METHODS

We analyzed data on children aged 12-23 months, extracted from the 2000 and 2019 Ethiopian Demographic and Health Survey (EDHS) datasets. A total of 3,072 weighted samples (2,076 in 2000 and 966 in 2019) were included in the analysis. A multivariate decomposition analysis technique was used to determine change and identify factors that contributed to the change over time. Statistical significance was defined at a 95% confidence interval with a p-value of less than 0.05.

RESULTS

There was a 29.56% (95% CI: 24.84, 34.28) change in full immunization coverage between the two surveys. It increased from 14.62% (95% CI: 12.43, 17.11) in 2000 to 44.18% (95% CI: 37.19, 51.41) in 2019. The decomposition analysis showed that about 75% of explained change was attributed to the differences in the composition of explanatory variables (the endowment effect). Particularly, women aged 35-49 years (-2.11%), those who attended four or more antenatal care visits (17.06%), individual who had postnatal care visits (16.90%), households with two or more under-five children (2.50%), and those with a history of child mortality (17.80%) were significantly attributed to the change. The rest, 25% of the explained change was attributed to the difference in the effects of explanatory variables (coefficient). The change in the coefficient for women who had experienced child death (-20.40%) was statistically significant to the change in full immunization coverage over time.

CONCLUSION

The finding of this study revealed that there was a statistically significant change in full immunization coverage over time. The majority of the change was attributed to the differences in the composition of explanatory variables such as antenatal care and postnatal care visits, age of the mother, and number of living children in the household. Therefore, strengthening maternal health services utilization may enhance immunization coverage in Ethiopia. Furthermore, the difference in coefficient of mothers with a history of child death had a substantial counteracting effect on the change, emphasizing the importance of raising awareness and delivering vaccine education to them and the larger community.

Contextual factors influencing incomplete immunization and investigation of its geospatial heterogeneity in Pakistan: a cross-sectional study based on PDHS (2017-18)

BACKGROUND

Immunization is one of the most effective public health initiatives, saving millions of lives and lowering the risk of diseases such as diphtheria, tetanus, influenza, and measles. Immunization saves an estimated 2-3 million lives per year. A study of the regional variations in incomplete immunization will be useful in identifying gaps in the performance of immunization programs that are not noticed by standard vaccination programs monitoring. The primary goal of this study was to identify factors influencing child immunization status and to examine regional variations in incomplete immunization among children aged 12 to 23 months in Pakistan.

METHODS

For the current study, the data were taken from the Demographic and Health Survey for Pakistan (PDHS 2017-2018). Ever-married women who had children aged 12-23 months were included in this study. The immunization status of children was used as an outcome variable. In order to determine the effects of different factors on incomplete immunization, multilevel logistic model was used. To study the geographical variation of incomplete immunization, hotspot analysis was done using ArcGIS 10.7 and SaTScan software and to identify significant predictors of incomplete immunization, GWR 4 software was used.

RESULTS

Place of delivery, gender of child, mother's educational level and region were identified as significant determinants of incomplete immunization of children in Pakistan. Chances of incomplete immunization of children were found significantly lower for educated mothers (AOR = 0.52, 95% CI 0.34-0.79) and mothers who had delivered children in the health facilities (AOR = 0.51, 95% CI 0.32-0.83). Female children were more likely (AOR = 1.44, 1.95% CI 1.04-1.99) to be incompletely immunized as compared to male children. FATA (AOR = 11.19, 95% CI 4.89-25.6), and Balochistan (AOR = 10.94, 95% CI 5.08-23.58) were found at the highest risk of incomplete immunization of children as compared to Punjab. The significant spatial heterogeneity of incomplete immunization was found across Pakistan. The spatial distribution of incomplete immunization was clustered all over Pakistan. The high prevalence of incomplete immunization was observed in Balochistan, South Sindh, North Sindh, South KPK, South FATA, Gilgit Baltistan, Azad Jammu Kashmir, South and East Punjab. Drang and Harcho were identified as hotspot areas of incomplete immunization in Gilgit Baltistan. Secondary clusters with a high risk of incomplete immunization were found in regions Balochistan, Sindh and FATA.

CONCLUSION

Gender biasedness towards female children, regarding complete immunization of children prevailed in Pakistan. Spatial heterogeneity was also found for incomplete immunization of children. To overcome the problem access to health facilities is the foremost step. Government should target hotspot areas of incomplete immunization of children to provide primary health care facilities by opening health care units in these areas. The government in collaboration with the media should launch awareness campaigns in those areas to convince people that complete immunization is the right of every child regardless of gender.

Factors Associated with Vaccination Uptake among Young Children: A Follow-Up Study of 1799 Toddlers

Childhood vaccination is crucial to protect young children from harmful infectious diseases. This study aimed to investigate the recent childhood immunization rate of recommended and additional vaccinations and identify the factors affecting the vaccination uptake of young children in Hong Kong. The self-administrated questionnaires were distributed to parents of toddlers aged 2 to 5. They were asked to provide information on (1) socioeconomic demographic factors; (2) experiences during pregnancy; and (3) the medical history of the toddler. A total of 1799 responses were collected. Children were more likely to be fully vaccinated when they were at a younger age (aOR = 0.61, 95% CI: 0.48–0.78, p < 0.001), the first child in the family (aOR second-born = 0.62, 95% CI: 0.48–0.81, p < 0.001; aOR third-born = 0.33, 95% CI: 0.19–0.55, p < 0.001), had a higher household income (aOR HKD 15,000–HKD 29,999 = 1.80, 95% CI: 1.27–2.55, p = 0.001; aOR ≥ HKD 30,000 = 3.42, 95% CI: 2.39–4.90, p < 0.001; compared with <HKD 15,000), or with mothers in older age groups (aOR 35–39 years old = 2.45, 95% CI = 1.22–4.93, p = 0.012; aOR ≥ 40 = 2.90, 95% CI = 1.24–6.77, p = 0.014; compared with ≤ age 24). The uptake of any additional vaccination was 71%. Children who were older (aOR = 1.32, 95% CI: 1.02–1.70, p = 0.036), the first child in the family (aOR second-born = 0.74, 95% CI: 0.56–0.99, p = 0.043; aOR third-born = 0.55, 95% CI: 0.32–0.96, p = 0.034), with higher household income (aOR ≥ HKD 30,000 = 1.61, 95% CI: 1.10–2.37, p = 0.016), were exposed to second-hand smoke from the father (aOR: 1.49, 95% CI: 1.08–2.07, p = 0.016), experienced hospitalization (twice or more—aOR: 1.44, 95% CI: 1.04–1.99, p = 0.027), or were fully vaccinated (aOR: 2.76, 95% CI: 2.12–3.60, p < 0.001) were associated with a higher chance of taking an additional vaccine. To encourage the vaccination rate, more attention should be given to families with more children, low-income families, and younger mothers.

Inequalities in Childhood Immunisation in South Asia

Identifying the inequalities associated with immunisation coverage among children is crucial. We investigated the factors associated with complete immunisation among 12- to 23-month-old children in five South Asian countries: Afghanistan, Bangladesh, India, Nepal, and Pakistan, using nationally representative data sets from the Demographic and Health Survey (DHS). Descriptive statistics, bivariate association, and logistic regression analyses were employed to identify the prevalence and the factors in each country that affect the likelihood of full childhood immunisation coverage. The complete childhood immunisation coverage varied significantly within each country in South Asia. Afghanistan had the lowest immunisation rates (42.6%), whereas Bangladesh ranked the highest in complete childhood immunisation rates, at 88.2%. Similarly, 77.1% of Indian children, 79.2% of Nepali children, and 62.2% of Pakistani children were completely immunised. Household wealth status strongly correlated with full childhood immunisation in Afghanistan, India, and Pakistan at the bivariate level. The results from the logistic regression showed that a higher maternal educational level had a statistically significant association with complete childhood immunisation in all countries compared to mothers who did not attend any school. In conclusion, the study revealed the inequalities of complete childhood immunisation within South Asia. Governments must be proactive in their endeavours to address universal and equitable vaccine coverage in collaboration with national and international stakeholders and in line with the relevant Sustainable Development Goals.

Factors associated with incomplete vaccination and negative antibody test results for measles, mumps, and hepatitis A among children followed in the MINA-BRAZIL cohort

Vaccination coverage has been dropping in Brazil and other countries. In addition, immune responses after vaccination may not be homogeneous, varying according to sociodemographic and clinical factors. Understanding the determinants of incomplete vaccination and negative antibody test results may contribute to the development of strategies to improve vaccination effectiveness. In this study, we aimed to investigate the frequency of vaccine adherence, factors associated with incomplete vaccination for measles, mumps, rubella (MMR) and hepatitis A, and factors associated with the seronegative test results for measles, mumps and hepatitis A at 2 years of age. This was a population-based cohort that addressed health conditions and mother/infant nutrition in Cruzeiro do Sul city, Brazil. Vaccination data were obtained from official certificates of immunization. The children underwent blood collection at the two-year-old follow-up visit; the samples were analyzed using commercially available kits to measure seropositivity for measles, mumps, and hepatitis A. We used modified Poisson regression models adjusted for covariates to identify factors associated with incomplete vaccination and negative serology after vaccination. Out of the 825 children included in the study, adherence to the vaccine was 90.6% for MMR, 76.7% for the MMRV (MMR + varicella), and 74.9% for the hepatitis A vaccine. For MMR, after the adjustment for covariates, factors associated with incomplete vaccination included: white-skinned mother; paid maternity leave; raising more than one child; lower number of antenatal consultations; and attending childcare. For hepatitis A, the factors included: white-skinned mother and not having a cohabiting partner. The factors with statistically significant association with a negative antibody test result included: receiving Bolsa Familia allowance for measles and mumps; incomplete vaccination for measles; and vitamin A deficiency for mumps. Strategies to improve the efficiency of vaccine programs are urgently needed. These include improvements in communication about vaccine safety and efficacy, and amplification of access to primary care facilities, prioritizing children exposed to the sociodemographic factors identified in this study. Additionally, sociodemographic factors and vitamin A deficiency may impact the immune responses to vaccines, leading to an increased risk of potentially severe and preventable diseases.

Factors affecting childhood immunization: Thematic analysis of parents and healthcare workers' perceptions

Immunization against common childhood diseases is an important strategy as it is critical for reducing the global child morbidity and mortality. This review explores the perceptions of parents and HCWs toward childhood immunization. The PRISMA guideline was used to search and include the studies. Relevant electronic databases were systemically searched for the years ranging from 2000 to 2021 to identify studies reported in English. Themes were then identified using thematic analysis. A total of 44 studies met the review criteria and were summarized and categorized into 4 themes: barriers to immunization, parental knowledge, attitude and behavior (KAB), health system factors and HCWs' KAB. This review found that immunization decision-making is a complex process. Parental KAB leads to immunization decisions. HCWs were also noted to be the trusted sources of immunization information. Further research can be conducted on how to improve parents' perceptions of immunization and immunization practices.

Impact of antenatal care visits on childhood immunization: a propensity score-matched analysis using nationally representative survey

BACKGROUND

Evidence has suggested a relationship between antenatal care (ANC) visits and childhood immunization coverage. However, evaluating its impact using observational data suffers from the problem of selection bias. Hence, we adopted propensity score-matched (PSM) analysis for studying the impact of ANC visits on childhood immunization.

METHODS

Data regarding ANC visits and childhood immunization were collected from a nationally representative survey, National Family Health Survey-4 (NFHS-4). We performed PSM analysis with logit model using the psmatch2 command package in STATA to find the average treatment effect on the population (ATE), treated (ATT), and untreated (ATU).

RESULTS

In total, 5,430 participants were included in the analysis. Radius matching with caliper width of 0.01 was used to match the groups. The ATT values in the intervention and control groups were 0.71 and 0.47, respectively, indicating that the immunization coverage was increased by 24% because of ANC visits. The ATU values in the intervention and control groups were 0.40 and 0.65, respectively. This indicates that for the women who did not make the ANC visits, the chance of getting their children immunized would have increased by 25% if they had made four or more visits. The final ATE estimate was 0.25 among the study participants. Quality of matching was good with no significant difference in characteristics between the two groups.

CONCLUSION

Findings from our study imply that policymakers in India should focus on further improving the ANC coverage as it has a significant impact on improving childhood immunization coverage.

Ethnic disparities in immunisation: analyses of zero-dose prevalence in 64 countries

BACKGROUND

The Sustainable Development Goals (SDGs) recommend stratification of health indicators by ethnic group, yet there are few studies that have assessed if there are ethnic disparities in childhood immunisation in low-income and middle-income countries (LMICs).

METHODS

We identified 64 LMICs with standardised national surveys carried out since 2010, which provided information on ethnicity or a proxy variable and on vaccine coverage; 339 ethnic groups were identified after excluding those with fewer than 50 children in the sample and countries with a single ethnic group. Lack of vaccination with diphtheria-pertussis-tetanus vaccine-a proxy for no access to routine vaccination or 'zero-dose' status-was the outcome of interest. Differences among ethnic groups were assessed using a χ2 test for heterogeneity. Additional analyses controlled for household wealth, maternal education and urban-rural residence.

FINDINGS

The median gap between the highest and lowest zero-dose prevalence ethnic groups in all countries was equal to 10 percentage points (pp) (IQR 4-22), and the median ratio was 3.3 (IQR 1.8-6.7). In 35 of the 64 countries, there was significant heterogeneity in zero-dose prevalence among the ethnic groups. In most countries, adjustment for wealth, education and residence made little difference to the ethnic gaps, but in four countries (Angola, Benin, Nigeria and Philippines), the high-low ethnic gap decreased by over 15 pp after adjustment. Children belonging to a majority group had 29% lower prevalence of zero-dose compared with the rest of the sample.

INTERPRETATION

Statistically significant ethnic disparities in child immunisation were present in over half of the countries studied. Such inequalities have been seldom described in the published literature. Regular analyses of ethnic disparities are essential for monitoring trends, targeting resources and assessing the impact of health interventions to ensure zero-dose children are not left behind in the SDG era.

Full immunization coverage and associated factors among children aged 12-23 months in Somali Region, Eastern Ethiopia

Objective

Despite those efforts in expanded programs of immunization, nearly one fifth of children in developing countries miss out basic vaccines. Moreover, many children who started vaccination fail to complete immunization.Identifying associated factorswhich is scarce in the study area, is crucial for interventions. This study assessed full-immunization and associated factors among children aged 12–23 months in Somali region, Eastern Ethiopia.

Methods

A community-based cross-sectional study design was conducted from October 1–30, 2018, in selected rural and urban kebeles in Somali regionamong 612 children. Cluster sampling was employed and data was collected using structured questionnaire. Full-immunization was measured by maternal recall and vaccination card.Data entry and analysis was done by EpiData3.1 and SPSSversion.20 respectively. Binary logistic regression with Bivariate and Multivariable model was usedto identify predictors of full-immunization. Odd ratios were computed and P-value <0.05 was considered as statistically significant.

Results

Based on maternal recall plus vaccination card 249(41.4%) of children were completed immunization, while vaccination only by card was 87(29.7%). Only 238(39.5%) of participants had good knowledge about vaccination. Not knowing to come back for next visits 197(55.8%) were the major reason for dropout. Residing in urban (AOR = 2.0, 95%CI: 1.0, 3.9),primary educated mothers(AOR = 2.2, 95%CI: 1.0, 5.0), married mothers (AOR = 4.2, 95%CI:1.0, 18), higher average monthly income (AOR = 2.5, 95%CI 1.1, 5.2)and delivered at health facilities (AOR = 3.8, 95%CI 1.9, 7.3)were significantly associated with full-immunization.

Conclusion

Coverage of full immunization was found to be low compared to the targets set in the Global Vaccine Action Plan(2011–2020).Two-third of the participants has poor knowledge about vaccination. Urban residence, mother education, higher family income, male child and institutional delivery were factors. This study suggests that awareness creation, behaviour change on vaccination and enhancing utilization of maternal health service including delivery service, should be stressed.

Factors Associated With Vaccination Compliance in Southeast Asian Children: A Systematic Review

Although vaccination coverage has reached a peak of 86% globally, around 19.9 million infants and children are yet to receive routine vaccinations-with Asia holding the highest prevalence of noncompliance. This implies notable gaps in vaccination coverage among some regions in the world. This study aims to analyze the factors associated with compliance toward childhood vaccination in Southeast Asia. A systematic review of observational studies was conducted using the following databases: PubMed, Scopus, and Cochrane. Included studies analyze factors affecting compliance with childhood vaccination in Southeast Asia, and assessed with Joanna Briggs Institute (JBI) and Newcastle-Ottawa Scale's criteria. Sixteen observational studies were included, with a total of 41 956 subjects, consisting of 15 cross-sectional studies and one case-control study. Our results suggested that parental personal-related, children and family status-related, socioeconomic, and health care-related factors strongly affected subjects' compliance with immunization. Prominent determinants were older maternal age, higher economics groups, parents in government or health care sectors, and frequent antenatal care visits. On the other hand, noncompliance were associated with younger age, large quantity of family members, lower economic groups, lower education, and unemployed parents. We hope that this comprehensive assessment thoroughly addresses challenges and inform strategies to raise compliance toward childhood vaccination in Southeast Asia.

Characterization of immunization secondary analyses using demographic and health surveys (DHS) and multiple indicator cluster surveys (MICS), 2006-2018

BACKGROUND

Infant immunization coverage worldwide has plateaued at about 85%. Using existing survey data to conduct analyses beyond estimating coverage may help immunization programmes better tailor strategies to reach un- and under-immunized children. The Demographic and Health Survey (DHS) and the Multiple Indicators Cluster Survey (MICS), routinely conducted in low and middle-income countries (LMICs), collect immunization data, yet vaccination coverage is often the only indicator reported and used. We conducted a review of published immunization-related analyses to characterize and quantify immunization secondary analyses done using DHS and MICS databases.

METHODS

We conducted a systematic search of the literature, of immunization-related secondary analyses from DHS or MICS published between 2006 and August 2018. We searched 15 electronic databases without language restrictions. For the articles included, relevant information was extracted and analyzed to summarize the characteristics of immunization-related secondary analyses. Results are presented following the PRISMA guidelines.

RESULTS

Among 1411 papers identified, 115 met our eligibility criteria; additionally, one article was supplemented by the Pan American Health Organization. The majority were published since 2012 (77.6%), and most (68.9%) had a first or corresponding author affiliated with institutions in high-income countries (as opposed to LMICs where these surveys are conducted). The median delay between survey implementation and publication of the secondary analysis was 5.4 years, with papers with authors affiliated to institutions in LMIC having a longer median publication delay (p < 0.001). Over 80% of the published analyses looked at factors associated with a specific vaccine or with full immunization. Quality proxies, such as reporting percent of immunization data from cards vs recall; occurrence and handling of missing data; whether survey analyses were weighted; and listing of potential biases or limitations of the original survey or analyses, were infrequently mentioned.

CONCLUSION

Our review suggests that more needs to be done to increase the increase the utilization of existing DHS and MICS datasets and improve the quality of the analyses to inform immunization programmes. This would include increasing the proportion of analyses done in LMICs, reducing the time lag between survey implementation and publication of additional analyses, and including more qualitative information about the survey in the publications to better interpret the results.

Vaccination assessments using the Demographic and Health Survey, 2005-2018: a scoping review

OBJECTIVE

To characterise studies which have used Demographic and Health Survey (DHS) datasets to evaluate vaccination status.

DESIGN

Scoping review.

DATA SOURCES

Electronic databases including PubMed, EBSCOhost and POPLINE, from 2005 to 2018.

STUDY SELECTION

All English studies with vaccination status as the outcome and the use of DHS data.

DATA EXTRACTION

Studies were selected using a predetermined list of eligibility criteria and data were extracted independently by two authors. Data related to the study population, the outcome of interest (vaccination) and commonly seen predictors were extracted.

RESULTS

A total of 125 articles were identified for inclusion in the review. The number of countries covered by individual studies varied widely (1-86), with the most published papers using data from India, Nigeria, Pakistan and Ethiopia. Many different definitions of full vaccination were used although the majority used a traditional schedule recommended in the WHO's Expanded Programme on Immunisation. We found studies analysed a wide variety of predictors, but the most common were maternal education, wealth, urbanicity and child's sex. Most commonly reported predictors had consistent relationships with the vaccination outcome, outside of sibling composition.

CONCLUSIONS

Researchers make frequent use of the DHS dataset to describe vaccination patterns within one or more countries. A clearer idea of past use of DHS can inform the development of more rigorous studies in the future. Researchers should carefully consider whether a variable needs to be included in the multivariable model, or if there are mediating relationships across predictor variables.

Predictors of immunization coverage among 12-23 month old children in Ethiopia: systematic review and meta-analysis

BACKGROUND

Immunization is one of modern medicine's greatest achievements in the last three decades. Annually it can prevent nearly 2 to 3 million deaths. Understanding the determinants of effective immunization coverage is a critical undertaking. Accordingly, we set out to check the best available evidence of outstanding predictors of immunization coverage among children aged 12-23 months in Ethiopia.

METHOD

Electronic databases including PubMed, Google Scholar, HINARI, and SCOPUS, Web of Science, African Journals Online, Ethiopian Medical Journals were searched. The search process, study selection, critical appraisal, and data extraction were done independently by two reviewers using Joanna Briggs Institute Meta-analysis for Review Instrument (JBI-MAStARI). The difference between reviewers was resolved with a third person. The risk of bias was assessed by the Newcastle Ottawa Tool for observational studies. Data were extracted using the Microsoft Excel checklist and exported to STATA 13. Heterogeneity was assessed using I2, Funnel plot and Egger's test was used to check for publication bias.

RESULTS

We identified 26 studies with 15,042 children with mothers/caretakers to assess factors associated with immunization coverage and significant factors were: maternal formal education, (OR = 2.45; 95% CI: 1.62-3.72), paternal formal education, (OR = 1.01; 95% CI: 0.27-3.77), residence, (OR = 2.11; 95% CI: 1.00-4.45), birth at health facility (OR = 1.86; 95% CI: 0.99-3.49), family size less than four, (OR = 1.81; 95% CI: 1.16-2.84), knowledge on age of immunization to be completed (OR = 6.18;95% CI: 3.07-12.43), knowledge on immunization schedule (OR = 2.49; 95% CI: 1.35-4.59), time to travel to health faculties, (OR = 1.74; 95% CI: 0.62-4.89), antennal care, (OR = 3.11; 95% CI: 1.64-5.88), and tetanus toxoid vaccination, (OR = 4.82; 95% CI: 2.99-7.75).

CONCLUSION

Our findings showed that literacy, residence, awareness, family size, maternal health services use, and proximity of the health facilities were factors associated with full immunization. This implies that there is a need for primary health service expansion and health education to "hard to reach areas" to improve immunization coverage for children aged 12-23 months.

Individual- and Community-Level Determinants for Complete Vaccination among Children Aged 12-23 Months in Ethiopia: A Multilevel Analysis

Background

Childhood vaccination continues to increase dramatically. In spite of the success of immunization programs to date, millions of children continued to die each year, and sub-Saharan Africa (SSA) accounted for the world's highest neonatal deaths. Childhood vaccination was designed as one of the most effective ways to reduce child mortalities from fatal vaccine-preventable diseases. Therefore, this study is aimed at investigating the individual- and community-level determinants of childhood complete vaccination in Ethiopia.

Methods

A secondary data analysis was done based on the 2016 Ethiopian Demographic and Health Survey (EDHS). A total weighted sample of 1,984 children aged 12-23 months was included for analysis. Considering the hierarchical nature of EDHS data, a two-level multilevel analysis for assessing individual- and community-level determinants of childhood complete vaccination was done. The intraclass correlation coefficient (ICC), Median Odds Ratio (MOR), Proportional Change in Variance (PCV), and deviance (-2LL) were used for model comparison and for checking model fitness. Variables with p value < 0.2 in the bivariable multilevel analysis were considered for the multivariable multilevel analysis. In the multivariable multilevel logistic regression analysis, the Adjusted Odds Ratio (AOR) with 95% Confidence Interval (CI) was reported to declare significant determinants of complete childhood vaccination.

Results

Overall complete vaccination status among children aged 12-23 months was 39% (95% CI: 36.8, 41.2). In the multilevel analysis, secondary or above educated mothers (AOR = 2.48; 95% CI: 1.41, 4.36), richest wealth status (AOR = 2.24; 95% CI: 1.16, 4.32), ≥four ANC visits (AOR = 2.77; 95% CI: 1.90-4.02), employed mothers (AOR = 1.66; 95% CI: 1.26, 2.18), urban residence (AOR = 1.84; 95% CI: 1.00, 3.51), and children in city administration (AOR = 2.66; 9% CI: 1.53, 4.62) were positively associated with vaccination status. On the other hand, children with a female household head (AOR = 0.68; 95% CI: 0.48, 0.96) were negatively associated.

Conclusion

Overall, childhood full vaccination status was low compared with the WHO targets. Maternal education, wealth status, ANC visit, maternal occupation, residence, region, and sex of household head were significant predictors of childhood complete vaccination. As a result, it is better to design a compensation mechanism to the costs associated with childhood vaccination for the poor households and strengthen awareness creation for rural residents to improve the access, utilization, and continuum of vaccination service.

Understanding the Improvement in Full Childhood Vaccination Coverage in Ethiopia Using Oaxaca-Blinder Decomposition Analysis

In Ethiopia, full vaccination coverage among children aged 12–23 months has improved in recent decades. This study aimed to investigate drivers of the improvement in the vaccination coverage. The Oaxaca–Blinder decomposition technique was applied to identify the drivers using data from Ethiopian Demographic and Health Survey conducted in 2000 and 2016. The vaccination coverage rose from 14.3% in 2000 to 38.5% in 2016. The decomposition analysis showed that most of the rise in vaccination coverage (73.7%) resulted from the change in the effect of explanatory variables over time and other unmeasured characteristics. Muslim religion had a counteracting effect on the observed increase in vaccination coverage. The remaining 26.3% of the increase was attributed to the change in the composition of the explanatory variables between 2000 and 2016, with maternal educational level and maternal health care utilization as significant contributors. The findings highlight the need for further improvements in maternal health care utilization and educational status to maintain the momentum towards universal coverage of childhood vaccination. Targeted intervention among Muslim-dominated communities is also needed to improve the current situation. Besides which, future studies need to be conducted to identify additional potential modifiable factors.

Cost-effectiveness of SMS appointment reminders in increasing vaccination uptake in Lagos, Nigeria: A multi-centered randomized controlled trial

OBJECTIVE

It is expected that mHealth largely contribute to increasing the coverages of key maternal and child health services. This study aims to estimate the cost-effectiveness of the SMS text reminders in clients' return visits to the health facilities for child vaccinations (incl. vitamin A supplementations), antenatal care (ANC) and family planning (FP), in urban communities of Lagos, Nigeria.

METHODS

A multi-centered randomized control trial was conducted at 33 primary health centers (PHCs) in Lagos, Nigeria. All the clients having visited any of the 33 PHCs for child vaccinations, ANC and FP were randomly assigned either to intervention group or to control group. The participants in the intervention group were sent an SMS text reminder two days before their appointments. Those not having showed up on the appointment dates received an additional SMS text reminder seven days after original appointment dates as defaulter tracing. The primary outcome was whether a client made return visit to PHCs for the upcoming appointments.

RESULTS

Of 12,779 appointments for 9,368 clients during the period of 1stApril to 30thJune 2019, 12,175 were included in the analysis. The return rate for child vaccinations in the intervention group was significantly higher (p < 0.001) by 4.8% - 6.0% than that in the control group, consistently across all the five different timings (on time as scheduled, and by 7 days, 14 days, 30 days, and 3 months after appointment dates). No significant difference between the two groups was detected in the increase in return rates for ANC and FP services. The incremental recurrent cost was estimated at 7.90 US Dollars per return case.

CONCLUSION

SMS text reminders led to a significant increase in the number of return visits for child vaccinations, Lagos, Nigeria, while no significant increase in return visits was confirmed for ANC and FP appointments.

Effect of vaccine reminder and tracker bracelets on routine childhood immunization coverage and timeliness in urban Pakistan (2017-18): a randomized controlled trial

Background

Inability to track children’s vaccination history coupled with parents’ lack of awareness of vaccination due dates compounds the problem of low immunization coverage and timeliness in developing countries. We evaluated the impact of two types of silicone immunization reminder bracelets for children in improving immunization coverage and timeliness of Pentavalent-3 and the Measles-1 vaccines.

Methods

Children < 3 months were enrolled in either of the 2 intervention groups (Alma Sana Bracelet Group and Star Bracelet Group) or the Control group. Children in the intervention groups were provided the two different bracelets at the time of recruitment. Each time the child visited the immunization center, a hole was perforated in the silicone bracelet to denote vaccine administration. Each child was followed up till administration of Measles-1 vaccine or till 12 months of age (if they did not come to the center for vaccination). Data was analyzed using the intention-to-treat population between groups. The unadjusted and adjusted Risk Ratios (RR) and 95% confidence interval (CI) for Pentavalent-3 and Measles-1 coverage at 12 months of age were estimated through bivariate and multivariate analysis. Time-to-Pentavalent-3 and Measles-1 immunization curves were calculated using the Kaplan–Meier method.

Results

A total of 1,445 children were enrolled in the study between July 19, 2017 and October 10, 2017. Baseline characteristics among the three groups were similar. Up-to-date coverage for the Pentavalent-3 /Measles-1 vaccine at 12 months of age was 84.6%/72.0%, 85.4%/70.5% and 83.0%/68.5% in Alma Sana Bracelet group, Star Bracelet group and Control group respectively but the differences were not statistically significant. In the multivariate analysis, neither the Alma Sana bracelet (adjusted RR = 1.01; 95% CI: 0.96-1.06), (adjusted RR: 1.05; 95% CI: 0.97-1.13) nor the Star bracelet (adjusted RR = 1.01; 95% CI: 0.96-1.06) (adjusted RR: 1.03; 95% CI: 0.95-1.11) was significantly associated with Pentavalent-3 vaccination or Measles-1 vaccination.

Conclusion

Although we did not observe any significant impact of the bracelets on improved immunization coverage and timeliness, our findings add to the existing literature on innovative, low cost reminders for health and make several suggestions for enhancing practical implementation of these tools.

Trial registration

ClinicalTrials.gov NCT03310762. Retrospectively Registered on October 16, 2017.

Association between ethnicity and under-5 mortality: analysis of data from demographic surveys from 36 low-income and middle-income countries

Background

The UN Sustainable Development Goals (SDGs) call for stratification of social indicators by ethnic groups; however, no recent multicountry analyses on ethnicity and child survival have been done in low-income and middle-income countries (LMICs).

Methods

We used data from Demographic and Health Surveys and Multiple Indicator Cluster Surveys collected between 2010 and 2016, from LMICs that provided birth histories and information on ethnicity or a proxy variable. We calculated neonatal (age 0–27 days), post-neonatal (age 28–364 days), child (age 1–4 years), and under-5 mortality rates (U5MRs) for each ethnic group within each country. We assessed differences in mortality between ethnic groups using a likelihood ratio test, Theil's index, and between-group variance. We used multivariable analyses of U5MR by ethnicity to adjust for household wealth, maternal education, and urban–rural residence.

Findings

We included data from 36 LMICs, which included 2 812 381 livebirths among 415 ethnic groups. In 25 countries, significant differences in U5MR by ethnic group were identified (all p<0·05 likelihood ratio test). In these countries, the median mortality ratio between the ethnic groups with the highest and lowest U5MRs was 3·3 (IQR 2·1–5·2; range 1·5–8·5), whereas among the remaining 11 countries, the median U5MR ratio was 1·9 (IQR 1·7–2·5; range 1·4–10·0). Ethnic gaps were wider for child mortality than for neonatal or post-neonatal mortality. In nearly all countries, adjustment for wealth, education, and place of residence did not affect ethnic gaps in mortality, with the exception of Guatemala, India, Laos, and Nigeria. The largest ethnic group did not have the lowest U5MR in any of the countries studied.

Interpretation

Significant ethnic disparities in child survival were identified in more than two-thirds of the countries studied. Regular analyses of ethnic disparities are essential for monitoring trends, targeting, and assessing the impact of health interventions. Such analyses will contribute to the effort towards leaving no one behind, which is at the centre of the SDGs.

Funding

Bill & Melinda Gates Foundation, UNICEF, Wellcome Trust, Associação Brasileira de Saúde Coletiva.

Vaccine coverage within the first year of life and associated factors with incomplete immunization in a Brazilian birth cohort

Background

Immunization has been held as a major achievement for global health, however, still exist many children who are not completely vaccinated. Knowledge about factors contributing to the incomplete immunization is important to develop effective strategies and interventions to achieve universal coverage to control or eradicate vaccine-preventable diseases. This study aimed to describe immunization coverage within the first year of life and associated factors with incompleteness among participants of the 2015 Pelotas Birth Cohort, Brazil.

Methods

Cross-sectional analyses were performed using data from a population-based cohort. Information on vaccination status was collected from immunization cards and verbal mother's reports from 4014 children aged 24 months. Coverage was described for each vaccine, for the basic and the complete national schedule. Incomplete vaccination was defined as failure to receive the recommended number of doses by the National Immunization Program in 2015. Bivariate and multivariate Poisson regressions with robust variance were conducted to identify factors associated with incompleteness.

Results

Vaccine coverage of individual vaccines varied from 81% (Hepatitis A) to 97% (BCG). Full immunization coverage were 77% (95% CI: 75.8; 78.4) and 66.1% (95% CI: 64.6; 67.5), for basic and expanded indicators, relatively. Multivariate analyses showed that factors associated with incompleteness (for both basic and expanded coverage) were high family income, high parity, low number of prenatal consultations, not have done the tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine during pregnancy, not have breastfeed the child until at age 12 months and not have used public health care services for child's vaccination.

Conclusion

Findings of our study show the need to develop and implement policies and programs to achieve complete immunization during the first year of life. Some strategies would include an increase in the primary health care services networks, improving their quality and access, the dissemination of scientific-based evidence about the benefits of vaccination, through communication campaigns and guidance provided by health professionals, especially those responsible for prenatal care.

Factors associated with the uptake of newly introduced childhood vaccinations in Ethiopia: the cases of rotavirus and pneumococcal conjugate vaccines

Background

Childhood immunization programmes have made substantial contributions to lowering the burden of disease among children in developing countries, however a large proportion of children still remain unimmunized. This study aimed to explore the determinants of rotavirus vaccine (RVV) and pneumococcal conjugate vaccine (PCV) uptake in Ethiopia.

Methods

The 2016 Ethiopian demographic and health survey dataset was used in this analysis. A total of 2004 children aged 12–23 months were included in the analysis. A multivariable logistic regression model was employed to identify the determinants of uptake of the complete schedules of RVV (two doses) and PCV (three doses). Crude and adjusted odds ratios with 95% confidence intervals (CIs) were calculated.

Results

The uptakes of the complete schedules of RVV and PCV among children aged 12–23 months were 56 and 49.1%, respectively. The likelihood of immunization with the complete schedule of RVV was significantly lower among children from the relatively poor Afar region in Ethiopia (AOR 0.16; 95%-CI 0.04–0.61). Similarly, children living in not only the Afar region (AOR 0.10; 95%-CI 0.03–0.38), but also the Gambela region (AOR 0.25; 95%-CI 0.08–0.83), were less likely to be vaccinated with PCV. On the other hand, children from more wealthy households had higher odds of vaccination with RVV (AOR 1.69; 95%-CI 1.04–2.75). Also attending antenatal care (ANC) was found to be significantly associated with uptake of the complete schedule of RVV and PCV.

Conclusions

The uptake of RVV and PCV is suboptimal in Ethiopia. The uptake of the vaccines were found to be associated with region, ANC use and wealth status.

Analyzing the Urban-Rural Vaccination Coverage Disparity through a Fair Decomposition in Zhejiang Province, China

Objectives: Exploring determinants underlying disparities in full vaccination coverage (FVC) can contribute to improved immunization interventions. FVC and its risk factors in Zhejiang province have been studied, yet the determinants explaining the rural-urban disparity in FVC have not been studied. This study aimed to disentangle the factors explaining rural-urban disparities in FVC of vaccine doses scheduled during the first year of life in Zhejiang province. Methods: We used data from a vaccination coverage survey among children aged 24-35 months conducted in 2016. The outcome measure was full vaccination status, and the grouping variable was the area of residence. Descriptive statistics were used to analyze the FVC and rural-urban residence across the exposure variables. The Fairlie decomposition technique was used to decompose factors contributing to explaining the FVC disparity. Results: There were 847 children included in this study, of which 49.6% lived in a rural area. FVC was 94% in rural areas and 85% in urban areas. A disparity of 9% to the advantage of the rural areas and the exposure variables explained 81.1% of the disparity. Maternal factors explained 49.7% of the explained disparity with education, occupation, and ethnicity being the significant contributors to the explained disparity. Children's birth order and immigration status contributed somewhat to the explained inequality. Conclusion: There was a significant disparity in FVC in Zhejiang province, a disadvantage to the urban areas. Policy recommendations or health interventions to reduce the inequality should be focused on eliminating poverty and women's illiteracy, targeted at migrant children or children from minority ethnicities.

Decomposing socioeconomic inequality in child vaccination in the Gambia, the Kyrgyz Republic and Namibia

Extant work suggested pro-rich distribution of vaccination coverage in low- and middle-income countries (LMICs). However, the current literature also suggested pro-poor distribution of vaccination in some countries, including the Gambia, the Kyrgyz Republic and Namibia. This study aimed to explain socioeconomic inequalities in the completion rate of the four-core vaccines (i.e., Bacille Calmette-Guérin [BCG], diphtheria-tetanus-pertussis [DTP, 3 doses], Polio [3 doses] and Measles vaccines) in the three aforementioned countries. We used the most recent available Demographic Health Surveys (DHS) to measure vaccination completion rates among children (aged 0-59 months, n = 16,752) in the three countries. The normalized concentration index (C_n) was used to quantify and decompose socioeconomic inequalities in vaccination coverage in each country. The negative values of the C_n index suggested that children belong to lower socioeconomic status groups were more likely to be immunized than their higher socioeconomic status counterparts in the Gambia (C_n = -0.101, 95% confidence interval [CI]: -0.128 to -0.074), the Kyrgyz Republic (C_n = -0.097, 95% CI: -0.13 to -0.063) and Namibia (C_n = -0.161, 95% CI: -0.199 to -0.124). The decomposition analysis of the C_n suggested that the difference in child vaccination completion rates between rural and urban areas was the main factor contributing to the concentration of child vaccination among the poor in the Gambia and Namibia. The concentration of child vaccination among the poor in the Kyrgyz Republic was chiefly determined by household wealth. These results suggest that there should be strategies to improve child immunization uptake among urban children in the Gambia and Namibia. Since household wealth was the main factor contributing to the observed pro-poor distribution of child vaccination in the Kyrgyz Republic, further studies are required to understand the reasons for lower vaccination rate among the wealthy children in order to implement the most effective strategies to increase child vaccination uptake.

Assessment of knowledge and attitude among postnatal mothers towards childhood vaccination in Malaysia

Aim: Mothers knowledge and attitude toward childhood vaccination influence uptake is the most adequate tool and preventive aspects to infectious disease epidemics. The present study assesses and measures knowledge and attitude of postnatal mothers toward vaccination.Methods and results: The present study adopted a cross-sectional study design, whereby 200 postnatal mothers were identified during their postnatal visit to clinics. The subjects were accessed using questionnaire to assess the level of knowledge and attitude of mothers regarding vaccination. The objectives were to study the level of knowledge, the attitude, and to find the association between knowledge and attitude of the study subjects. The data were analyzed using SPSS version 16. The results was analyzed through chi-square test. The association between age (p = .031), education (p = .021), occupation (p = .013), and knowledge score toward vaccination was found to be statistically significant. However, ethnicity (p = .127), employment (p = .197), and mode of delivery (p = .750) toward mothers vaccination knowledge were not significant for the study. Mothers education, age, and occupation were found to be associated with attitude toward childhood vaccination. No association was found between ethnicity, employment, and mode of delivery with attitude of childhood vaccination.Conclusion: More than half of the studied mothers had good knowledge scores on vaccination, more than two-thirds of the studied mothers had good attitude scores on vaccination. However, the religious misconception and fear of autism was the main cause of vaccine resistance in Malaysia.

Determinants of Timely Presentation for Birth Dose Vaccination at an Immunization Centre in North-central Nigeria

Background:

Timely receipt of immunization is an essential prerequisite to ensure early protection of the child. However, a low proportion of children in Nigeria benefit from the timely administration of the birth dose vaccines.

Objectives:

These were identification of factors associated with timely presentation and reasons for presentation beyond 24 hours at an immunization centre in Ilorin, Nigeria.

Method:

A descriptive cross-sectional study involving 480 mother-infant pairs was conducted at an immunization centre. Socio-demographic, antenatal care (ANC) and delivery details, infant’s birthday and day of presentation for vaccination were recorded. Logistic regression was used to identify factors associated with time to presentation within day one.

Findings:

239 (49.8%), 421 (87.7%) and 454 (94.6%) babies were vaccinated within days one, seven and 14 respectively. Post-secondary education level of mothers (OR = 3.60; 95% C.I: 1.30–9.91), antenatal care attendance (OR = 9.55; 95% C.I: 1.75–52.12), and hospital delivery (OR = 6.36; 95% C.I: 1.33–30.38) were associated with presentation within day one. Having correct knowledge of the immunization schedule increased the odds of early presentation by three times, p = 0.025. The commonest reason for presentation after day one for vaccination was weekend/public holiday delivery identified in 83 (35.2%) mother-infant pairs.

Conclusion:

Hospital delivery, attendance at antenatal care, postsecondary education and knowledge of the immunization schedule were factors associated with timely presentation for birth dose vaccination. Strategies to improve timeliness of the birth dose vaccination should target babies delivered outside the hospital as well as during weekends in the hospital. Also, inclusion of immunization into the health education curriculum of schools could be beneficial.

The impact of supplementary immunization activities on routine vaccination coverage: An instrumental variable analysis in five low-income countries

Background

Countries deliver vaccines either through routine health services or supplementary immunization activities (SIAs), usually community-based or door-to-door immunization campaigns. While SIAs have been successful at increasing coverage of vaccines in low- and middle-income countries, they may disrupt the delivery of routine health services. We examine the impact of SIAs on routine vaccine coverage in five low-income countries.

Methods

Data on the number and timing of SIAs conducted in various countries was compiled by WHO and obtained through UNICEF. Information on the coverage of vaccines not targeted by SIAs (e.g., DPT) was extracted from the Demographic and Health Surveys. We focus on SIAs that took place between 1996 and 2013 in Bangladesh, Senegal, Togo, Gambia, and Cote d’Ivoire, and examine outcomes for children aged 12–59 months. To avoid biases resulting from non-random placement and timing of SIAs, we use age of a child at her first SIA as an instrumental variable for total exposure to SIAs.

Results

We find that SIA exposure reduced the likelihood of receiving routine vaccines in all the countries included in the study; the coefficients of interest are however statistically insignificant for Gambia and Cote d’Ivoire. In countries that witnessed statistically significant SIA-induced declines in the likelihood of obtaining DPT 3, measles as well as BCG, reductions ranged from 1.3 percentage points (Senegal) to 5.5 percentage points (Bangladesh).

Conclusion

SIA exposure reduced routine vaccination rates in study countries. Efforts should be made to limit the detrimental impact of SIAs on the services provided by routine health systems.

Factors affecting complete and timely childhood immunization coverage in Sindh, Pakistan; A secondary analysis of cross-sectional survey data

BACKGROUND

Pakistan has a high burden of newborn mortality, which would be significantly preventable through appropriate routine immunization. The purpose of this study was to measure the basic timely childhood immunization coverage and to identify determinants of factors influencing childhood immunization coverage in Sindh, Pakistan.

METHODS

Data from Maternal and Child Health Program Indicator Survey 2013-2014 which was conducted in Sindh province of Pakistan was used. Outcome measure was full coverage of the basic immunization schedule from child's vaccination card. The association of receiving basic immunization with demographic factors, socioeconomic status, mother and child health information sources, and perinatal care factors were tested by binary logistic regression.

RESULTS

Among 2,253 children, 1,156 (51.3%) received age-based full basic immunization. The basic immunization rates were 69.1% for under five weeks old, 38.3% for six to nine weeks, 18.8% for 10-13 weeks, 44.0% for 14 weeks-eight months, 60.4% for nine to 11 months, and 59.1% for over one year. Child's age, number of living children, parents' education level, wealth, the source of mother and child health information, number of antenatal care, and assistance during delivery were associated with completing basic immunization.

CONCLUSIONS

The overall full basic immunization coverage in Pakistan was still low. Policy makers should identify children at risk of low immunization coverage and obstacles of receiving antenatal care, implement educational interventions targeting on less educated parents, and conduct mass immunization campaigns for timely and complete immunization.

Measuring childhood vaccination acceptance of mother in Zhejiang province, East China

BACKGROUND

The aim of this study was to evaluate the vaccine hesitancy among mothers and examine risk factors associated with mother's intention to vaccination in Zhejiang province.

METHODS

A provincial sample of mothers of children aged 24-35 months was surveyed (N = 770) in August, 2017. Demographic information, perception on the past childhood vaccination, knowledge on vaccination, information searches and needs, trust in different institutions on vaccination were collected. Based on the theory of planned behaviour (TPB), attitudes toward vaccination, perceived social support, perceived behavioural control as well as mothers' intention to immunize their child were constructed. Descriptive statistics were generated for all variables. Univariate and multivariate analyses were performed to identify differences between mothers who had strong intentions to immunize their children in future and those with weaker intentions.

RESULTS

Of the participants, 79.6% had a positive attitudes towards vaccination, 77.5% had a high perceived social support, 63.2% had a high perceived behaviour control and 87.3% strongly intended to have their child vaccinated. Strong intention to vaccination was significantly associated with the positive behavioral attitudes [adjusted odds ratios (AOR) = 3.2, 95% CI: 2.3-5.7], the high perceived social support (AOR = 2.8, 95% CI: 1.8-3.6), the perceived ease of undergoing vaccination (AOR = 2.1, 95% CI: 1.6-3.3), respectively.

CONCLUSIONS

It was recommended that interventions focused on trust-building, promoting social norms, changing the negative attitude would be effective to enhance the maternal acceptance on vaccination.

The effect of maternal decisional authority on children's vaccination in East Asia

Even though they are important determinants for increasing vaccination rates in advanced and developing nations alike, maternal capacity and decisional authority have not been fully elucidated in diverse countries and cultural spheres. This study examined the effects of South Korean, Chinese, and Japanese mothers' health literacy, self-efficacy, mass media use, and decisional authority on their children's vaccination after adjustment for their socioeconomic statuses. Computer-assisted web interviews were conducted with married women in their 20s-40s of South Korean, Chinese, or Japanese nationality (n = 1,571). Dependent variables were generated for the following four vaccinations: BCG, diphtheria+pertussis+tetanus (DPT), poliomyelitis (polio), and measles. For statistical processing, cases where all four types of vaccines had been recorded were scored as 1 and other cases were processed as 0. According to the results of the pooled model, we found that for East Asian mothers, decisional authority, self-efficacy, and health literacy all increased the likelihood that they would vaccinate their children. Furthermore, women who searched for health information through media such as the radio were more likely to vaccinate their children. However, when elaborate analyses were conducted by country, there were considerable differences in those characteristics by country. Therefore, this study showed that it is necessary to establish locally tailored strategies in order to raise vaccination rates in the Global Vaccine Action Plan. This study also showed that social contexts must be taken into consideration in order to raise vaccination rates.

Vaccination knowledge and acceptability among pregnant women in Italy

The aims of this survey were to ascertain pregnant women's level of knowledge and acceptability on the vaccinations and to identify their associations with several characteristics. A cross-sectional study was performed from December 2017 through March 2018 in the geographic area of Naples, Italy. The study used two stages cluster sampling method for selection and recruitment of participants. Data were collected through face-to-face interviews with pregnant women present at the Obstetrics outpatient clinic of the selected hospitals. A total of 358 respondents agreed to be interviewed out of the 405 pregnant women selected. One-fourth knew at least one of the vaccinations recommended during pregnancy and only 2.8% correctly identified all of these. Women who had received information about the vaccinations during pregnancy from general practitioners or gynecologists or other sources and those with at least one child were more likely to know at least one of the recommended vaccinations, whereas women with middle school education were less knowledgeable. None of the women had received tetanus, diphtheria, and acellular pertussis vaccine and only 1.4% the seasonal influenza vaccination. Only 27.9% reported a positive willingness to receive all the recommended vaccinations during pregnancy. Pregnant women would be willing to get all recommended vaccinations if they had at least one child and if they needed additional information, whereas the willingness was significantly lower among women who had reported high school as the highest level of education, who were in the second trimester of pregnancy, and who felt that the recommended vaccines administered during pregnancy were less dangerous for them and for the unborn child. This study suggests important focus points to be taking into account for informing and for implementing education activities on the benefits regarding vaccinations in order to increase the level of knowledge and the uptake in pregnant women.

Determinants of compliance with child immunization among mothers of children under five years of age in Ekiti State, Nigeria

Purpose

Vaccine preventable diseases are major threats to the health and well-being of children under five years of age. They contribute a great deal to childhood illnesses and disabilities, and are accountable for a high percentage of childhood mortality worldwide. In Nigeria, the government has made a lot of effort to provide immunizations against these childhood diseases. It is however sad to note that many children still do not complete their routine immunization. The purpose of this paper is to determine factors which influence mothers’ compliance with childhood immunization.

Design/methodology/approach

This was a descriptive study carried out among 600 mothers of under-five children randomly selected from nine postnatal clinics in Ekiti State between January and August 2016. A self-structured validated questionnaire containing items to explore demographic characteristics of respondents, compliance with child immunization (Cronbach’s α=0.92) and determinants of compliance (Cronbach’s α=0.83) was the instrument for data collection. Multiple regression analysis was used to identify determinants of mothers’ compliance with childhood immunization.

Findings

The level of compliance of mothers with childhood immunization was high (80 percent). The two factors which contributed significantly to mothers’ compliance were the mothers’ knowledge of childhood immunization (β weight= 0.243) and mothers’ educational status (β weight=0.169). Mothers with tertiary education had the highest level of compliance (76.8 percent).

Originality/value

Having good knowledge of childhood immunization and a high educational status positively influence a mothers’ compliance with child immunization.

Socioeconomic inequalities in child vaccination in low/middle-income countries: what accounts for the differences?

Background

Socioeconomic inequalities in child vaccination continue to be a global public health concern. This study aimed to measure and identify factors associated with socioeconomic inequalities in full immunisation coverage against the four core vaccine-preventable diseases (ie, bacille Calmette-Guérin, diphtheria-tetanus-pertussis (three doses), polio (three doses) and measles vaccines) in 46 low/middle-income countries.

Methods

The most recent nationally representative samples of children (aged 10–59 months, n=372 499) collected through the Demographic Health Surveys were used to measure vaccination rates. The concentration index (C) was used to quantify socioeconomic inequalities in vaccination coverage. Furthermore, meta-regression analyses were used to determine factors affecting socioeconomic inequalities in vaccination coverage across countries.

Results

Results suggested that immunisation coverage was pro-rich in most countries (median C=0.161, IQR 0.131). Gambia (C=−0.146, 95% CI −0.223 to −0.069), Namibia (C=−0.093, 95% CI −0.145 to −0.041) and Kyrgyz Republic (C=−0.227, 95% CI −0.304 to −0.15) were the only countries where children who belong to higher socioeconomic status group were less likely to receive all the four core vaccines than their lower socioeconomic status counterparts. Meta-regression analyses suggested that, across countries, the concentration of antenatal care visits among wealthier mothers was positively associated with the concentration of vaccination coverage among wealthier children (coefficient=0.606, 95% CI 0.301 to 0.911).

Conclusions

Pro-rich distribution of child vaccination in most low/middle-income countries remains an important public health policy concern. Policies aimed to improve antenatal care visits among mothers in lower socioeconomic groups may mitigate socioeconomic inequalities in vaccination coverage in low/middle-income countries.

Determinants of immunization status among 12- to 23-month-old children in Indonesia (2008-2013): a multilevel analysis

BACKGROUND

Immunization is one of the most cost-effective public health interventions to prevent children from contracting vaccine-preventable diseases. Indonesia launched the Expanded Program for Immunization (EPI) in 1977. However, immunization coverage remains far below the United Nations International Children's Emergency Fund (UNICEF) and World Health Organization (WHO) target of 80%. This study aims to investigate the determinants of complete immunization status among children aged 12-23 months in Indonesia.

METHODS

We used three waves of the Indonesian National Socioeconomic Survey (2008, 2011, and 2013) and national village censuses from the same years. Multilevel logistic regression was used to conduct the analysis.

RESULTS

The number of immunized children increased from 47.48% in 2008 to 61.83% in 2013. The presence of health professionals, having an older mother, and having more educated mothers were associated with a higher probability of a child's receiving full immunization. Increasing the numbers of hospitals, village health posts, and health workers was positively associated with children receiving full immunization. The MOR (median odds ratio) showed that children's likelihood of receiving complete immunization varied significantly among districts.

CONCLUSIONS

Both household- and district-level determinants were found to be associated with childhood immunization status. Policy makers may take these determinants into account to increase immunization coverage in Indonesia.

Determinants of immunisation coverage of children aged 12-59 months in Indonesia: a cross-sectional study

OBJECTIVES

Despite the adoption of WHO's Expanded Programme on Immunisation in Indonesia since 1977, a large proportion of children are still completely unimmunised or only partly immunised. This study aimed to assess factors associated with low immunisation coverage of children in Indonesia.

SETTING

Children aged 12-59 months in Indonesia.

PARTICIPANT

The socioeconomic characteristics and immunisation status of the children were obtained from the most recent Demographic and Health Survey, the 2012 Indonesia Demographic and Health Survey. Participants were randomly selected through a two-stage stratified sampling design. Data from 14 401 children aged 12-59 months nested within 1832 census blocks were included in the analysis. Multilevel logistic regression models were constructed to account for hierarchical structure of the data.

RESULTS

The mean age of the children was 30 months and they were equally divided by sex. According to the analysis, 32% of the children were fully immunised in 2012. Coverage was significantly lower among children who lived in Maluku and Papua region (adjusted OR: 1.94; 95% CI 1.42 to 2.64), were 36-47 months old (1.39; 1.20 to 1.60), had higher birth order (1.68; 1.28 to 2.19), had greater family size (1.47; 1.11 to 1.93), whose mother had no education (2.13; 1.22 to 3.72) and from the poorest households (1.58; 1.26 to 1.99). The likelihood of being unimmunised was also higher among children without health insurance (1.16; 1.04 to 1.30) and those who received no antenatal (3.28; 2.09 to 5.15) and postnatal care (1.50; 1.34 to 1.69).

CONCLUSIONS

Socioeconomic factors were strongly associated with the likelihood of being unimmunised in Indonesia. Unimmunised children were geographically clustered and lived among the most deprived population. To achieve WHO target of protective coverage, public health interventions must be designed to meet the needs of these high-risk groups.

Knowledge, Attitude and Practice of Pregnant Women towards Varicella and Their Children's Varicella Vaccination: Evidence from Three Distrcits in Zhejiang Province, China

Background: The objectives of this study were to examine the knowledge, attitudes and practice (KAP) towards varicella and varicella vaccine (VarV) vaccination among pregnant women in three distrcits in Zhejiang Province, China. Methods: From 1 January to 31 March 2014, pregnant women with ≥12 gestational weeks were recruited and received a self-administrated questionnaire. The first dose of VarV (VarV1) vaccination status of children from present pregnancy was extracted at 24 months of age from Zhejiang provincial immunization information system (ZJIIS). Three variables was defined as the main outcomes, which included: (1) knowing about both the availability of VarV and the number of doses required; (2) positive attitude towards the utility of varicella vaccination; (3) the vaccination coverage of VarV1, which meant the proportion of children having received the VarV1. Counts and proportions were used to describe the socio-demographic characteristics of study participants, and their relationship with study outcomes were tested using chi-square tests in univariate analysis and logistic regression in multivariable analysis. Results: A total of 629 pregnant women participated in this study. The majority of the participants (68.0%) answered correctly about the transmission route of varicella. The proportion of participants who heard about varicella vaccination was 76.5% and 66.8% knew that VarV was currently available. Only 13.5% of the participants answered correctly that the complete VarV series needed two doses. Age, immigration status, education level, household income, and number of children of the pregnant women were significant predictors of the KAP regarding the VarV vaccination. Conclusions: The current survey indicated that optimal KAP levels and coverage on VarV vaccination were observed in three districts of Zhejiang Province. Health education programs on varicella and VarV vaccination directed towards both pre-natal and post-natal women are needed, which will result in a better attitude on vaccination of VarV and in a high coverage of VarV.

Determinants of inequality in the up-to-date fully immunization coverage among children aged 24-35 months: Evidence from Zhejiang province, East China

OBJECTIVE

This study aimed to determine the degree and determinants of inequality in up-to-date fully immunization (UTDFI) coverage among children of Zhejiang province, east China.

METHOD

We used data from the Zhejiang provincial vaccination coverage survey of 2014 and the health outcome was the UTDFI status among children aged 24-35 months. The household income per month was used as an index of socio-economic status for the inequality analysis. The concentration index (CI) was used to quantify the degree of inequality and the decomposition approach was applied to quantify the contributions from demographic factors to inequality in UTDFI coverage.

RESULTS

The UTDFI coverage was 80.63% and the CI for UTDFI coverage was 0.12028 (95% CI: 0.10852-0.13175), indicating that immunization practice significantly favored children with relatively higher socio-economic status. The results of decomposition analysis suggested that 68.2% of the socio-economic inequality in UTDFI coverage should be explained by the mother's education level. Furthermore, factors such as birth order, ethnic group, maternal employment status, residence, immigration status, GDP per-capital and percentage of public health spending of the total health spending also could explain the disparity in UTDFI coverage.

CONCLUSION

There exists inequality in UTDFI coverage among the socio-economic disadvantage children. Health interventions of narrowing the socio-economic inequality in UTDFI coverage will benefit from being supplemented with strategies aimed at poverty and illiteracy reduction.

Maternal education, empowerment, economic status and child polio vaccination uptake in Pakistan: a population based cross sectional study

OBJECTIVES

To explore the association of maternal education and empowerment with childhood polio vaccination using nationally representative data of Pakistani mothers in a reproductive age group.

DESIGN

Cross-sectional.

SETTING

Secondary analysis of Pakistan Demographic and Health Survey (PDHS), 2012-2013 data was performed.

PARTICIPANTS

Of the 13 558 mothers included in the survey sample, 6982 mothers were able to provide information regarding polio vaccinations.

MAIN OUTCOME MEASURES

Polio vaccination coverage among children aged up to 5 years was categorised as complete vaccination (all four oral polio vaccine (OPV) doses), incomplete vaccination, and no vaccination (zero OPV dose received). Mothers' empowerment status was assessed using standard 'Measure DHS' questions regarding their involvement in decision-making related to health, household possessions and visits among family and friends. Education was categorised as no education, primary, secondary and higher education. Results of multinomial regression analyses were reported as adjusted OR with 95% CI. We adjusted for age, wealth index, urban/rural residence, place of delivery, and antenatal and postnatal visits.

RESULTS

Only 56.4% (n=3936) of the children received complete polio vaccination. Women with no education had significantly higher odds of their child receiving no polio vaccination (OR 2.34, 95% CI 1.05 to 5.18; p<0.01) and incomplete vaccination (OR 1.40, 95% CI 1.04 to 1.87; p<0.01). Further, unempowered women also had significantly higher odds of not taking their child for any polio vaccination (OR 1.58, 95% CI 1.17 to 2.12; p<0.01) and incomplete vaccination (OR 1.18, 95% CI 1.00 to 1.41; p=0.04).

CONCLUSIONS

Illiteracy, socioeconomic status and empowerment of women remained significant factors linked to poorer uptake of routine polio vaccination.

Factors affecting the implementation of childhood vaccination communication strategies in Nigeria: a qualitative study

BACKGROUND

The role of health communication in vaccination programmes cannot be overemphasized: it has contributed significantly to creating and sustaining demand for vaccination services and improving vaccination coverage. In Nigeria, numerous communication approaches have been deployed but these interventions are not without challenges. We therefore aimed to explore factors affecting the delivery of vaccination communication in Nigeria.

METHODS

We used a qualitative approach and conducted the study in two states: Bauchi and Cross River States in northern and southern Nigeria respectively. We identified factors affecting the implementation of communication interventions through interviews with relevant stakeholders involved in vaccination communication in the health services. We also reviewed relevant documents. Data generated were transcribed verbatim and analysed using thematic analysis.

RESULTS

We used the SURE framework to organise the identified factors (barriers and facilitators) affecting vaccination communication delivery. We then grouped these into health systems and community level factors. Some of the commonly reported health system barriers amongst stakeholders interviewed included: funding constraints, human resource factors (health worker shortages, training deficiencies, poor attitude of health workers and vaccination teams), inadequate infrastructure and equipment and weak political will. Community level factors included the attitudes of community stakeholders and of parents and caregivers. We also identified factors that appeared to facilitate communication activities. These included political support, engagement of traditional and religious institutions and the use of organised communication committees.

CONCLUSIONS

Communication activities are a crucial element of immunization programmes. It is therefore important for policy makers and programme managers to understand the barriers and facilitators affecting the delivery of vaccination communication so as to be able to implement communication interventions more effectively.

Did you get your shots? Experimental evidence on the role of reminders

Many families fail to vaccinate their children despite the supply of these services at no cost. This study tests whether personal reminders can increase demand for vaccination. A field experiment was conducted in rural Guatemala in which timely reminders were provided to families whose children were due for a vaccine. The six-month intervention increased the probability of vaccination completion by 2.2 percentage points among all children in treatment communities. Moreover, for children in treatment communities who were due to receive a vaccine, and whose parents were expected to be reminded about that due date, the probability of vaccination completion increased by 4.6 percentage points. The cost of an additional child with complete vaccination due to the intervention is estimated at about $7.50.

Correlation between pediatrician supply and public health in Japan as evidenced by vaccination coverage in 2010: secondary data analysis

Background

In industrialized countries, assessment of the causal effect of physician supply on population health has yielded mixed results. Since the scope of child vaccination is an indicator of preventive health service utilization, this study investigates the correlation between vaccination coverage and pediatrician supply as a reflection of overall pediatric health during a time of increasing pediatrician numbers in Japan.

Methods

Cross-sectional data were collected from publicly available sources for 2010. Dependent variables were vaccination coverage for measles and diphtheria, pertussis, and tetanus (DPT) by region. The primary predictor of interest was number of pediatricians per 10 000-child population (pediatrician density) at the municipality level. Multivariate logistic regression models were used to estimate associations of interest, conditional on a large range of demographic and infrastructure-related factors as covariates, including non-pediatric physician density, total population, per capita income, occupation, unemployment rate, prevalence of single motherhood, number of hospital beds per capita, length of roads, crime rate, accident rate, and metropolitan area code as urban/rural status. The percentage of the population who completed college-level education or higher in 2010 was included in the model as a proxy for education level.

Results

Pediatrician density was positively and significantly associated with vaccination coverage for both vaccine series. On average, each unit of pediatrician density increased odds by 1.012 for measles (95% confidence interval, 1.010–1.015) and 1.019 for DPT (95% confidence interval, 1.016–1.022).

Conclusions

Policies increasing pediatrician supply contribute to improved preventive healthcare services utilization, such as immunizations, and presumably improved child health status in Japan.

Increased use of recommended maternal health care as a determinant of immunization and appropriate care for fever and diarrhoea in Ghana: an analysis pooling three demographic and health surveys

OBJECTIVE

Enhancing maternal and child health are key Millennium Development Goals (MDGs). This study examined whether increased utilization of recommended maternal health care (MHC), is associated with factors that improve children's health; specifically, complete immunization and appropriate care for fever and diarrhoea in Ghana.

DESIGN

Data from the 1998, 2003, and 2008 Ghana Demographic and Health Surveys were pooled for a nationally representative sample of 6786 women aged 15-49 years who had a child in the previous 5 years. Children aged 12-23 months were considered fully immunized if they received all eight basic immunizations. Appropriate care for children under-five was receipt of medical treatment for fever or oral rehydration therapy for diarrhoea. The effect of recommended MHC utilization (characterized as poor, intermediate or best use) on immunization and appropriate care for fever and diarrhoea was determined through logistic regression with Andersen's Behavioural Model guiding co-variate selection.

RESULTS

Increased MHC utilization (reference: intermediate MHC use) increased the odds of immunization [poor use: odds ratio (OR) = 0.54, 95% confidence interval (CI): 0.42-0.69; best use: OR = 1.29, 95% CI: 1.01-1.67], as well as appropriate care for fever (poor use: OR = 0.55, 95% CI: 0.35-0.88; best use: OR = 1.72, 95% CI: 1.17-2.52) and diarrhoea (poor use: OR = 0.63, 95% CI: 0.43-0.93). Survey year and region also predicted each outcome. Other determinants of immunization were maternal education, ethnicity, religion, media exposure, wealth and birth weight. Determinants of appropriate care for fever included paternal education, media exposure and wealth, and for diarrhoea, child's age and birth weight.

CONCLUSION

This study proposes a linkage between MDGs; initiatives to improve maternal health through promoting increased use of recommended MHC may enhance children's health-related care. This could be useful for countries with limited resources in achieving MDGs, especially in sub-Saharan Africa where under-five mortality is the highest.

Reasons for non-vaccination in pediatric patients visiting tertiary care centers in a polio-prone country

Background

The Expanded Program on Immunization (EPI) was initiated by World Health Organization (WHO) in 1974 in order to save children from life threatening, disabling vaccine-preventable diseases (VPDs). In Pakistan, this program was launched in 1978 with the main objectives of eradicating polio by 2012, eliminating measles and neonatal tetanus by 2015, and minimizing the incidence of other VPDs. However, despite the efforts of government and WHO, this program has not received the amount of success that was desired. Hence, the objectives of this study were to elucidate the main reasons behind not achieving the full immunization coverage in Pakistan, the awareness of children’s attendant about the importance of vaccination, their attitudes, thoughts and fears regarding childhood immunization, and the major hurdles faced in pursuit of getting their children vaccinated.

Methods

This was an observational, cross-sectional, questionnaire-based study conducted during a one year period from 4th January, 2012 to 6th January, 2013 at the pediatric outpatient clinics of Civil Hospital (CHK) and National Institute of Child Health (NICH). We attempted to interview all the parents who could be approached during the period of the study. Thus, convenience sampling was employed. The parents were approached in the clinics and interviewed after seeking informed, written consent. Those patients who were not accompanied by either of their parents were excluded from the study. The study instrument comprised of three sections. The first section consisted was concerned with the demographics of the patient and the parents. The second section dealt with the reasons for complete vaccination or under-vaccination. The last section aimed to assess the knowledge, attitudes and beliefs of the respondents.

Results

Out of 1044 patients, only 713(68.3%) were fully vaccinated, 239(22.9%) were partially vaccinated while 92(8.8%) had never been vaccinated. The vaccination status showed statistically significant association with ethnicity, income, residence, number of children and paternal occupation (p < 0.05 for all). The most common provocative factor for vaccination compliance was mass media (61.9%). The most common primary reason for non-vaccination was lack of knowledge (18.1%), whereas the most common secondary reason for non-vaccination was religious taboos (31.4%). Majority of the respondents demonstrated poor knowledge of EPI schedules or VPDs. However, most believed that there was a need for more active government/NGO involvement in this area.

Conclusion

The most common primary reason for non-vaccination, i.e. lack of knowledge, and the most common secondary reason, i.e. religious taboos, imply that there is dire need to promote awareness among the masses in collaboration with NGOs, and major religious and social organizations.

Strategies to Improve Child Immunization via Antenatal Care Visits in India: A Propensity Score Matching Analysis

Numerous studies have examined the empirical evidence concerning the influence of demographic and socio-economic factors influencing child immunization, but no documentation is available which shows the actual impact of antenatal care (ANC) visits on subsequent child immunization. Therefore, this paper aims to examine the net impact of ANC visits on subsequent utilization of child immunization after removing the presence of selection bias. Nationwide data from India's latest National Family Health Survey conducted during 2005-06 is used for the present study. The analysis has been carried out in the two separate models, in the first model 1-2 ANC visit and in the second model three or more ANC visits has been compared with no visit. We have used propensity score matching method with a counterfactual model that assesses the actual ANC visits effect on treated (ANC visits) and untreated groups (no ANC visit), and have employed Mantel-Haenszel bounds to examine whether result would be free from hidden bias or not. Using matched sample analysis result shows that child immunization among the groups of women who have completed 1-2 ANC visits and those who had more than two visits was about 13 percent and 19 percent respectively, higher than the group of women who have not made any ANC visit. Findings of nearest neighbor matching with replacement method, which completely eliminated the bias, indicate that selection bias present in data set leads to overestimates the positive effects of ANC visits on child immunization. Result based on Mantel-Haenszel bounds method suggest that if around 19 percent bias would be involved in the result then also we could observe the true positive effect of 1-2 ANC visits on child immunization. This also indicates that antenatal clinics are the conventional platforms for educating pregnant women on the benefits of child immunization.

Face to face interventions for informing or educating parents about early childhood vaccination

BACKGROUND

Childhood vaccination (also described as immunisation) is an important and effective way to reduce childhood illness and death. However, there are many children who do not receive the recommended vaccines because their parents do not know why vaccination is important, do not understand how, where or when to get their children vaccinated, disagree with vaccination as a public health measure, or have concerns about vaccine safety.Face to face interventions to inform or educate parents about routine childhood vaccination may improve vaccination rates and parental knowledge or understanding of vaccination. Such interventions may describe or explain the practical and logistical factors associated with vaccination, and enable parents to understand the meaning and relevance of vaccination for their family or community.

OBJECTIVES

To assess the effects of face to face interventions for informing or educating parents about early childhood vaccination on immunisation uptake and parental knowledge.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 7); MEDLINE (OvidSP) (1946 to July 2012); EMBASE + Embase Classic (OvidSP) (1947 to July 2012); CINAHL (EbscoHOST) (1981 to July 2012); PsycINFO (OvidSP) (1806 to July 2012); Global Health (CAB) (1910 to July 2012); Global Health Library (WHO) (searched July 2012); Google Scholar (searched September 2012), ISI Web of Science (searched September 2012) and reference lists of relevant articles. We searched for ongoing trials in The International Clinical Trials Registry Platform (ICTRP) (searched August 2012) and for grey literature in The Grey Literature Report and OpenGrey (searched August 2012). We also contacted authors of included studies and experts in the field. There were no language or date restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and cluster RCTs evaluating the effects of face to face interventions delivered to individual parents or groups of parents to inform or educate about early childhood vaccination, compared with control or with another face to face intervention. Early childhood vaccines are all recommended routine childhood vaccines outlined by the World Health Organization, with the exception of human papillomavirus vaccine (HPV) which is delivered to adolescents.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed database search results for inclusion. Grey literature searches were conducted and reviewed by a single author. Two authors independently extracted data and assessed the risk of bias of included studies. We contacted study authors for additional information.

MAIN RESULTS

We included six RCTs and one cluster RCT involving a total of 2978 participants. Three studies were conducted in low- or middle-income countries and four were conducted in high-income countries. The cluster RCT did not contribute usable data to the review. The interventions comprised a mix of single-session and multi-session strategies. The quality of the evidence for each outcome was low to very low and the studies were at moderate risk of bias overall. All these trials compared face to face interventions directed to individual parents with control.The three studies assessing the effect of a single-session intervention on immunisation status could not be pooled due to high heterogeneity. The overall result is uncertain because the individual study results ranged from no evidence of effect to a significant increase in immunisation.Two studies assessed the effect of a multi-session intervention on immunisation status. These studies were also not pooled due to heterogeneity and the result was very uncertain, ranging from a non-significant decrease in immunisation to no evidence of effect.The two studies assessing the effect of a face to face intervention on knowledge or understanding of vaccination were very uncertain and were not pooled as data from one study were skewed. However, neither study showed evidence of an effect on knowledge scores in the intervention group. Only one study measured the cost of a case management intervention. The estimated additional cost per fully immunised child for the intervention was approximately eight times higher than usual care.The review also considered the following secondary outcomes: intention to vaccinate child, parent experience of intervention, and adverse effects. No adverse effects related to the intervention were measured by any of the included studies, and there were no data on the other outcomes of interest.

AUTHORS' CONCLUSIONS

The limited evidence available is low quality and suggests that face to face interventions to inform or educate parents about childhood vaccination have little to no impact on immunisation status, or knowledge or understanding of vaccination. There is insufficient evidence to comment on the cost of implementing the intervention, parent intention to vaccinate, parent experience of the intervention, or adverse effects. Given the apparently limited effect of such interventions, it may be feasible and appropriate to incorporate communication about vaccination into a healthcare encounter, rather than conduct it as a separate activity.

Ethnic Disparities in Routine Immunization Coverage

Karachi is the only mega city in the world with persistent poliovirus transmission. We determined routine childhood immunization rates in Karachi and identified predictors of vaccine completion. A population-based cross-sectional survey was conducted in Karachi between August and September 2008. Data on demographics, socioeconomic, and DTP3 vaccination status in children 12 to 23 months old were collected. Logistic regression was used to identify predictors of vaccination completion. Overall, 1401 participants were approached; 1391 consented to participate. Of these, 1038 (75%) were completely vaccinated. Punjabi families had the highest DTP3 coverage (82%), followed by Urdu-speaking families (79%). Pashtun (67%) and Bengali (48%) families had the lowest vaccine coverage. Children of mothers with ≥12 years of schooling (OR = 25.4; 95% CI = 5.7-113.1) were most likely to be vaccinated. A quarter of study participants were unvaccinated. Targeted strategies for boosting DTP3 rates in communities with low immunization coverage are essential for polio eradication in Karachi.