Risk factors for delayed immunization among children in an HMO

Determinants of parental vaccine hesitancy in Canada: results from the 2017 Childhood National Immunization Coverage Survey

BACKGROUND

In 2019, the World Health Organization (WHO) designated vaccine hesitancy as one of the ten leading threats to global health. Vaccine hesitancy exists when vaccination services are available and accessible, but vaccine uptake is lower than anticipated. It is often attributed to lack of trust in vaccine safety and effectiveness, or low level of concern about the risk of many vaccine-preventable diseases. This study aimed to examine the sociodemographic factors associated with parental vaccine hesitancy and vaccine refusal in Canada using data from the 2017 Childhood National Immunization Coverage Survey (CNICS).

METHOD

The 2017 CNICS was a cross-sectional and nationally representative survey to estimate national vaccine uptake and to collect information about parents' Knowledge, Attitudes and Beliefs (KAB) regarding vaccination. Using the KAB questions, parental vaccine hesitancy (i.e., parental hesitation, delay or refusal of at least one recommended vaccination) and refusal (i.e., unvaccinated children) by sociodemographic factors was estimated using weighted prevalence proportions. A multinomial logistic regression model was fitted to examine associations between parental vaccine hesitancy or refusal and sociodemographic factors among parents of two-year-old children in Canada. Adjusted odds ratios (aOR) of being vaccine-hesitant or vaccine-refusing versus being non-vaccine-hesitant were generated.

RESULTS

Both unadjusted and adjusted logistic regressions models showed that parents with lower household income (aOR 1.7, 95% CI 1.2-2.5), and those with a higher number of children in the household (aOR 2.2, 95% CI 1.4-3.5) had higher vaccine hesitancy. Conversely, lower vaccine hesitancy was observed among non-immigrant parents (aOR 0.4, 95% CI 0.3-0.6). In addition, lower household income (aOR 4.0, 95% CI 1.3-12.9), and higher number of children in the household (aOR 6.9, 95% CI 2.1-22.9) were significantly associated with parental vaccine refusal. Regional variations were also observed.

CONCLUSION

Several sociodemographic determinants are associated with parental vaccine hesitancy and refusal. The findings of the study could help public health officials and policymakers to develop and implement targeted interventions to improve childhood vaccination programs.

Magnitude and associated factors of delayed vaccination among children aged 11-23 months in, Tigray, Ethiopia, 2018

BACKGROUND

Delay in receiving the vaccination is a major public health problem that has been associated with vaccine-preventable disease epidemics. In Ethiopia, many children have not received the benefits of age-appropriate vaccination; thus more than 90% of child deaths are largely due to preventable communicable diseases.

OBJECTIVE

The present study assessed the magnitude and associated factors of delayed vaccination among 12-23 months old children in Tigray, Ethiopia.

METHODS

A community-based cross-sectional study was carried out among 393, 12-23 months old children from July 1 to 30, 2018. Data were collected using a structured interviewer-administered questionnaire. The questionnaire includes socio-demographic, economic factors, Maternal/caregiver factors, Child's factors, and Service-related factors. We applied bivariable and multivariable logistic regression to determine predictors for delayed Vaccination. The odds ratio with 95% CI was computed to evaluate the strength of the association.

RESULTS

393 participants were involved in the study. The magnitude of delayed vaccination was 29.5% (95% CI 26.7-45). Mothers who attend tertiary (University/college) education (AOR 0.169, 95% CI 0.032-0.882), and secondary education (AOR 0.269, 95% CI 0.114-0.636) had the protective effect of delayed vaccination. But the sickness of a child (AOR = 11.8, 95% CI 6.16-22.65) was a risk for delayed vaccination.

CONCLUSIONS

The magnitude of delayed vaccination was high, particularly among participants with Mother's education, and Mother's consideration in the child's wellness to take the vaccine. This implies that it is important to give emphasis, especially for the mothers who have an uneducated and sick child to increase awareness about the advantage of vaccination, which will improve on-time vaccination.

Explaining socio-economic inequalities in immunization coverage in Nigeria

Globally, in 2013 over 6 million children younger than 5 years died from either an infectious cause or during the neonatal period. A large proportion of these deaths occurred in developing countries, especially in sub-Saharan Africa. Immunization is one way to reduce childhood morbidity and deaths. In Nigeria, however, although immunization is provided without a charge at public facilities, coverage remains low and deaths from vaccine preventable diseases are high. This article seeks to assess inequalities in full and partial immunization coverage in Nigeria. It also assesses inequality in the 'intensity' of immunization coverage and it explains the factors that account for disparities in child immunization coverage in the country. Using nationally representative data, this article shows that disparities exist in the coverage of immunization to the advantage of the rich. Also, factors such as mother's literacy, region and location of the child, and socio-economic status explain the disparities in immunization coverage in Nigeria. Apart from addressing these issues, the article notes the importance of addressing other social determinants of health to reduce the disparities in immunization coverage in the country. These should be in line with the social values of communities so as to ensure acceptability and compliance. We argue that any policy that addresses these issues will likely reduce disparities in immunization coverage and put Nigeria on the road to sustainable development.

Family Characteristics Associated with Likelihood of Varicella Vaccination

CONTEXT

The introduction of the varicella vaccine as a routine pediatric immunization in the US, in 1995, provided an opportunity to assess factors associated with uptake of new vaccines in the member population of the Kaiser Permanente Northwest (KPNW) Health Plan.

OBJECTIVE

Identify factors associated with varicella vaccination in the KPNW population in the first five years after varicella vaccine was introduced.

DESIGN

A retrospective cohort of children under age 13 years between June 1995 and December 1999, without a history of varicella disease was identified using KPNW automated data. Membership records were linked to vaccine databases. Cox regression was used to estimate likelihood of varicella vaccination during the study period in relation to age, sex, primary clinician's specialty, and Medicaid eligibility. For a subset whose parents answered a behavioral health survey, additional demographic and behavioral characteristics were evaluated.

MAIN OUTCOME MEASURE

Varicella vaccination.

RESULTS

We identified 88,646 children under age 13 years without a history of varicella; 22% were vaccinated during the study period. Varicella vaccination was more likely among children who were born after 1995, were not Medicaid recipients, or had pediatricians as primary clinicians. In the survey-linked cohort, positively associated family characteristics included smaller family size; higher socioeconomic status; and parents who were older, were college graduates, reported excellent health, and received influenza vaccination.

CONCLUSION

Understanding predictors of early varicella vaccine-era vaccine acceptance may help in planning for introduction of new vaccines to routine schedules.

Childhood immunizations in China: disparities in health care access in children born to North Korean refugees

Background

Childhood immunization rates are at an all-time high globally, and national data for China suggests close to universal coverage. Refugees from North Korea and their children may have more limited health care access in China due to their legal status. However, there is no data on immunization rates or barriers to coverage in this population.

Methods

This study was conducted to determine the rates and correlates of immunizations in children (≥1 year) born to North Korean refugees in Yanbien, China. Child immunization data was obtained from vaccination cards and caregiver self-report for 7 vaccines and 1:3:3:3:1 series. Age-appropriate vaccination rates of refugee children were compared to Chinese and migrant children using a goodness-of-fit test. Logistic regression was used to determine correlates of immunization coverage for each vaccine and the 1:3:3:3:1 series.

Results

Age-appropriate immunization coverage rates were significantly lower in children born to North Korean refugees (12.1-97.8 %), compared to Chinese (99 %) and migrant (95 %) children. Increased father’s age and having a sibling predicted significantly lower vaccination rates.

Conclusions

Children born to North Korean refugees had significantly lower immunization rates, compared to Chinese or migrant children. Further research is needed to examine barriers of health care access in this high-risk population.

Childhood vaccination coverage rates among military dependents in the United States

BACKGROUND AND OBJECTIVES

The Military Health System provides universal coverage of all recommended childhood vaccinations. Few studies have examined the effect that being insured by the Military Health System has on childhood vaccination coverage. The purpose of this study was to compare the coverage of the universally recommended vaccines among military dependents versus other insured and uninsured children using a nationwide sample of children.

METHODS

The National Immunization Survey is a multistage, random-digit dialing survey designed to measure vaccination coverage estimates of US children aged 19 to 35 months old. Data from 2007 through 2012 were combined to permit comparison of vaccination coverage among military dependent and all other children.

RESULTS

Among military dependents, 28.0% of children aged 19 to 35 months were not up to date on the 4:3:1:3:3:1 vaccination series excluding Haemophilus influenzae type b vaccine compared with 21.1% of all other children (odds ratio: 1.4; 95% confidence interval: 1.2-1.6). After controlling for sociodemographic characteristics, compared with all other US children, military dependent children were more likely to be incompletely vaccinated (odds ratio: 1.3; 95% confidence interval: 1.1-1.5).

CONCLUSIONS

Lower vaccination coverage rates among US military dependent children might be due to this population being highly mobile. However, the lack of a military-wide childhood immunization registry and incomplete documentation of vaccinations could contribute to the lower vaccination coverage rates seen in this study. These results suggest the need for further investigation to evaluate vaccination coverage of children with complete ascertainment of vaccination history, and if lower immunization rates are verified, assessment of reasons for lower vaccination coverage rates among military dependent children.

Determinant of factors associated with child health outcomes and service utilization in Ghana: multiple indicator cluster survey conducted in 2011

Background

The effects of National Health Insurance Scheme in Ghana and its impact on child health outcome and service utilization cannot be underestimated. Despite the tremendous improvement in child health care in Ghana, there are still some challenges in relation to how National health insurance membership, socioeconomic status and other demographic factors impacts on child health outcomes. The study seeks to determine the association between NHIS membership, socio-economic status, geographic location and other relevant background factors, on child health service utilization and outcomes.

Methods

Secondary data from the Multiple Indicator Cluster Survey conducted in 2011 was used. Multivariate analysis based on Binary Logistic Regression Models and Multiple linear regression techniques was applied to determine factors associated with child health outcomes and service utilization. Collection of best models was based on Hosmer-Lemeshow Goodness-Of-Fit as one criterion of fit and the Akaike Information Criterion.

Results

Controlling for confounding effect of socioeconomic status, age of the child, mothers education level and geographic location, the odds of a child developing anemia for children with National Health Insurance Scheme Membership is 65.2% [95% CI: 52.9-80.2] times less than children without National Health Insurance Scheme Membership. The odds of being fully immunized against common childhood illnesses for children with NHIS membership is 2.3[95% CI: 1.4-3.7] times higher than children without National Health Insurance Scheme Membership. There was no association between National Health Insurance Scheme Membership and stunted growth in children.

Conclusions

National Health Insurance Scheme Membership was found to be related to child health service utilization (full immunization) of children under five a child’s anemia status. Children with NHIS are more likely to be fully immunized against common childhood diseases and are less likely to develop anemia. Stunted growth of children was not associated with National Health Insurance Scheme Membership. Health Education on the registration and the use of the National Health Insurance should be made a national priority to enable the Ministry of Health achieve routine Immunization targets and to reduce to the bearers minimum prevalence of anemia.

Age-specific strategies for immunization reminders and recalls: a registry-based randomized trial

BACKGROUND

Although previous studies have found reminder/recall to be effective in increasing immunization rates, little guidance exists regarding the specific ages at which it is optimal to send reminder/recall notices.

PURPOSE

To assess the relative effectiveness of centralized reminder/recall strategies targeting age-specific vaccination milestones among children in urban areas during June 2008-June 2009.

METHODS

Three reminder/recall strategies used capabilities of the Michigan Care Improvement Registry (MCIR), a statewide immunization information system: a 7-month recall strategy, a 12-month reminder strategy, and a 19-month recall strategy. Eligible children were randomized to notification (intervention) or no notification groups (control). Primary study outcomes included MCIR-recorded immunization activity (administration of ≥1 new dose, entry of ≥1 historic dose, entry of immunization waiver) within 60 days following each notification cycle.

RESULTS

A total of 10,175 children were included: 2,072 for the 7-month recall, 3,502 for the 12-month reminder, and 4,601 for the 19-month recall. Immunization activity was similar between notification versus no notification groups at both 7 and 12 months. Significantly more 19-month-old children in the recall group (26%) had immunization activity compared to their counterparts who did not receive a recall notification (19%).

CONCLUSIONS

Although recall notifications can positively affect immunization activity, the effect may vary by targeted age group. Many 7- and 12-month-olds had immunization activity following reminder/recall; however, levels of activity were similar irrespective of notification, suggesting that these groups were likely to receive medical care or immunization services without prompting.

[The impact of multiple vaccinations on vaccine schedule adherence and parental attitudes in Monteregie]

OBJECTIVE

This study aimed to explore the impact of adding new vaccines on schedule adherence and parental opinion of multiple injections.

METHOD

A descriptive cross-sectional study by self-administered questionnaire mailed to a stratified random sample of each of two cohorts of children drawn from the Montérégie Birth Register: the 2002-2003 cohort (old vaccination schedule) and the 2004-2005 cohort (new schedule). Two surveys were done: Survey 1 (fall 2005-winter 2006) questioned parents whose address could be validated by Canada411.ca; Survey 2 (fall 2006) surveyed parents whose address was validated by the Quebec health insurance board (RAMQ). Incomplete or missing vaccine data were completed by verifying the vaccinators' files.

RESULTS

Analysis of schedule adherence by the Kaplan-Meier survival approach showed that the 2nd and 3rd doses of the DTaP-P-Hib vaccine were received late by the youngest children compared to the oldest (median number of days late: 2 days for the 2nd vaccine (p = 0.013) and 4 days for the 3rd vaccine (p < 0.001)). Many parents (76%) prefer 2 to 3 injections during a single visit, and 61% fear an increase in the risk of side effects.

CONCLUSION

Even if the evaluated lateness has only a small public health impact, parents must be reassured about the safety of multiple vaccines.

Related factors of age-appropriate immunization among urban-rural children aged 24-35 months in a 2005 population-based survey in Nonsan, Korea

PURPOSE

This study was aimed to determine the status and related factors of age-appropriate immunization among urban-rural children aged 24-35 months in a 2005 population-based survey in Nonsan, Korea.

MATERIALS AND METHODS

We conducted household survey and provider check using questionnaire and checklist to obtain data on immunization status for children, aged 24-35 months. Age-appropriate immunization was defined as status of receiving the fourth diphtheria-tetanus-pertussis (4 DTP), 3 Polio, the first measles-mumps-rubella (1 MMR) doses, and the 4 : 3 : 1 series.

RESULTS

Age-appropriate immunization rates were 51.7% for 4 DPT, 88.0% for 3 Polio, 87.9% for 1 MMR, and 50.3% for the 4 : 3 : 1 series. First-born children, lower perceived barrier scores, and higher perception of immunization data were significantly related to age-appropriate immunization.

CONCLUSION

The findings indicated that age-appropriate immunization rate could be improved by implementing reminder/recall service and providing the knowledge about immunization. Identification and consideration related factors would improve immunization rate and age-appropriate immunization.

Tracking parental attitudes on vaccination across European countries: The Vaccine Safety, Attitudes, Training and Communication Project (VACSATC)

The paper presents the first results from the European project VACSATC which aimed to track parental attitudes on vaccinations across several European countries. We compared five cross-sectional surveys of parents with children less than 3 years of age in England, Norway, Poland, Spain and Sweden carried out during 2008-2009. Data were collected from 6611 respondents. Two countries used face-to face interviews, one used telephone interviews, and two other countries used mail-in questionnaires. In all countries health professionals were indicated as the most important and trusted source of information on vaccination. The study results also show that parental attitudes on vaccinations in the childhood vaccination programs are generally positive. However, there were differences in attitudes on vaccination between the five countries, possibly reflecting different methods of sampling the respondents, context-specific differences (e.g. level of activity of governmental agencies), but also individual-level parental variation in demographic and socioeconomic status variables.

Perception of barriers to immunization among parents of Hmong origin in California

OBJECTIVES

We explored factors associated with perception of barriers to immunization among parents of Hmong origin in California, whose children experience persistent immunization inequities even with health insurance.

METHODS

A partnership of academic researchers and members of the Hmong community conducted a community-based participatory research project. We collected data in naturalistic settings with a standardized instrument. We analyzed responses from 417 parents and caregivers and created a structural equation model to determine factors that contributed to perceived barriers.

RESULTS

Of 3 potential contributing factors to perceived barriers-nativity, socioeconomic position, and use of traditional Hmong health care (i.e., consulting shamans and herbalists)-the latter 2 significantly predicted higher perceived barriers to immunization. Nativity, indicated by years in the United States, age of arrival in the United States, and English language fluency, did not predict perceived barriers.

CONCLUSIONS

Interventions aimed at reducing immunization inequities should consider distinct sociocultural factors that affect immunization rates among different refugee and immigrant groups.

[Risk factors for delayed or missed measles vaccination in young children]

Because of low measles vaccine coverage rates, measles outbreaks have been observed several times during recent years in Germany. The aim of this study is to identify parents' attitudes and beliefs towards immunisations and socio-economic factors which are associated with delayed or missed first measles vaccination in young children. We used data from a representative German-wide immunisation survey on 2116 children born between 1 January 2002 and December 2004 by collecting precise vaccination information from vaccination cards. The influence of socio-economic determinants and parental attitudes towards immunisations on the timing of the first measles dose was analysed by using multivariable Cox regression. Of these children 46.8% (95% CI: 44.5-49.1) received their first measles dose according to the recommendations of the standing committee on vaccination (STIKO) by month 15. In multivariable analysis, fathers aged 28-33 years and birth order as well as parents' belief in homeopathy and other parental attitudes indicating lack of knowledge about the importance of vaccinations significantly influenced an early immunisation. Not general opposition, but insufficient parental knowledge about the harmfulness of measles infection seemed to be responsible for the low measles vaccination rates.

The immunization status of home-schooled children in America

The immunization of children against a vast number of life-threatening infectious agents has been hailed as one of the greatest public health interventions of the twentieth century. In America, the morbidity and mortality associated with many common childhood infectious diseases has all but vanished. State-based school entry vaccination laws play a significant role in achieving high immunization rates among children and adolescents. Alarmingly, there is no consistent regulation in place to monitor the immunization status of the ever-growing home-schooled population. It is widely unknown whether the nearly 2 million home-schooled children are adequately immunized. As the home schooling movement continues to gain ground in the United States, pediatric nurse practitioners in the primary care setting will play an important role in protecting the health of these children, as well as the public's health.

A medical home versus temporary housing: the importance of a stable usual source of care

OBJECTIVES

Little is known about how the stability of a usual source of care (USC) affects access to care. We examined the prevalence of USC changes among low-income children and how these changes were associated with unmet health care need.

METHODS

We conducted a cross-sectional survey of Oregon's food stamp program in 2005. We analyzed primary data from 2681 surveys and then weighted results to 84087 families, adjusting for oversampling and nonresponse. We then ascertained the percentage of children in the Oregon population who had ever changed a USC for insurance reasons, which characteristics were associated with USC change, and how USC change was associated with unmet need. We also conducted a posthoc analysis of data from the Medical Expenditure Panel Survey to confirm similarities between the Oregon sample and a comparable national sample.

RESULTS

Children without a USC in the Oregon population had greater odds of reporting an unmet health care need than those with a USC. This pattern was similar in national estimates. Among the Oregon sample, 23% had changed their USC because of insurance reasons, and 10% had no current USC. Compared with children with a stable USC, children who had changed their USC had greater odds of reporting unmet medical need, unmet prescription need, delayed care, unmet dental need, and unmet counseling need.

CONCLUSIONS

This study highlights the importance of ensuring stability with a USC. Moving low-income children into new medical homes could disturb existing USC relationships, thereby merely creating "temporary housing."

New vaccines against otitis media: projected benefits and cost-effectiveness

OBJECTIVE

New vaccines that offer protection against otitis media caused by nontypeable Haemophilus influenzae and by Moraxella catarrhalis are under development. However, the potential health benefits and economic effects of such candidate vaccines have not been systematically assessed.

METHODS

We created a computerized model to compare the projected benefits and costs of (1) the currently available 7-valent pneumococcal conjugate vaccine, (2) a candidate pneumococcal-nontypeable H influenzae vaccine that has been tested in Europe, (3) a hypothetical pneumococcal-nontypeable H influenzae-Moraxella vaccine, and (4) no vaccination. The clinical probabilities of acute otitis media and of otitis media with effusion were generated from multivariate analyses of data from 2 large health maintenance organizations and from the Pittsburgh Child Development/Otitis Media Study cohort. Other probabilities, costs, and quality-of-life values were derived from published and unpublished sources. The base-case analysis assumed vaccine dose costs of $65 for the 7-valent pneumococcal conjugate vaccine, $100 for the pneumococcal-nontypeable H influenzae vaccine, and $125 for the pneumococcal-nontypeable H influenzae-Moraxella vaccine.

RESULTS

With no vaccination, we projected that 13.7 million episodes of acute otitis media would occur annually in US children aged 0 to 4 years, at an annual cost of $3.8 billion. The 7-valent pneumococcal conjugate vaccine was projected to prevent 878,000 acute otitis media episodes, or 6.4% of those that would occur with no vaccination; the corresponding value for the pneumococcal-nontypeable H influenzae vaccine was 3.7 million (27%) and for the pneumococcal-nontypeable H influenzae-Moraxella vaccine was 4.2 million (31%). Using the base-case vaccine costs, pneumococcal-nontypeable H influenzae vaccine use would result in net savings compared with nontypeable 7-valent pneumococcal conjugate use. Conversely, pneumococcal-nontypeable H influenzae-Moraxella vaccine use would not result in savings compared with pneumococcal-nontypeable H influenzae vaccine use, but would cost $48 000 more per quality-adjusted life-year saved. The results were sensitive to variations in assumptions on vaccine effectiveness and vaccine dose costs but not to variations in other assumptions.

CONCLUSIONS

New candidate vaccines against otitis media have the potential to prevent millions of disease episodes in the United States annually. If priced comparably with other recently introduced vaccines, these new otitis vaccines could achieve cost-effectiveness comparable with or more favorable than that of the 7-valent pneumococcal conjugate vaccine.

A usual source of care: supplement or substitute for health insurance among low-income children?

OBJECTIVES

To examine the separate and combined effects of having health insurance and a usual source of care (USC) on access to healthcare for low-income children and to determine if one or the other is superior in ensuring better access to necessary services.

METHODS

We conducted cross-sectional, multivariable analyses of data from a mail-return survey of Oregon's food stamp program. Results from 2681 completed surveys were weighted back to a population of 84,087 families with adjustments for oversampling techniques and nonresponse.

RESULTS

Among low-income Oregon children, those with health insurance and a USC reported the best access to healthcare. In multivariable comparisons to this reference group, insured children without a USC had higher rates of unmet medical need [odds ratio (OR) = 2.18; 95% confidence interval (CI): 1.27-3.73]; no doctor visits in 12 months (OR = 6.77; 95% CI: 3.80-12.06); and problems obtaining specialty care (OR = 4.12; 95% CI: 1.59-10.68). Similarly, having a USC but not health insurance was associated with an even higher likelihood of unmet medical needs (OR = 4.33; 95% CI: 2.85-6.57); as well as unmet prescription needs (OR = 2.64, 95% CI: 1.77-3.94), and problems obtaining dental care (OR = 4.83; 95% CI: 3.31-7.06).

CONCLUSIONS

Incremental policy solutions are being proposed that focus on either health insurance coverage for children or expanded access to primary care. However, neither approach displaces the need for the other. The effects of a USC and health insurance, together, are additive predictors of the likelihood that children have optimal access to necessary healthcare services.

Parents with doubts about vaccines: which vaccines and reasons why

OBJECTIVES

The goals were (1) to obtain national estimates of the proportions of parents with indicators of vaccine doubt, (2) to identify factors associated with those parents, compared with parents reporting no vaccine doubt indicators, (3) to identify the specific vaccines that prompted doubt and the reasons why, and (4) to describe the main reasons parents changed their minds about delaying or refusing a vaccine for their child.

METHODS

Data were from the National Immunization Survey (2003-2004). Groups included parents who ever got a vaccination for their child although they were not sure it was the best thing to do ("unsure"), delayed a vaccination for their child ("delayed"), or decided not to have their child get a vaccination ("refused").

RESULTS

A total of 3924 interviews were completed. Response rates were 57.9% in 2003 and 65.0% in 2004. Twenty-eight percent of parents responded yes to ever experiencing >or=1 of the outcome measures listed above. In separate analyses for each outcome measure, vaccine safety concern was a predictor for unsure, refused, and delayed parents. The largest proportions of unsure and refused parents chose varicella vaccine as the vaccine prompting their concern, whereas delayed parents most often reported "not a specific vaccine" as the vaccine prompting their concern. Most parents who delayed vaccines for their child did so for reasons related to their child's illness, unlike the unsure and refused parents. The largest proportion of parents who changed their minds about delaying or not getting a vaccination for their child listed "information or assurances from health care provider" as the main reason.

CONCLUSIONS

Parents who exhibit doubts about immunizations are not all the same. This research suggests encouraging children's health care providers to solicit questions about vaccines, to establish a trusting relationship, and to provide appropriate educational materials to parents.

Timely immunization series completion among children of immigrants

This study examines the relationship between timely immunization series completion among children of immigrants and parental nativity, residential duration in the United States, and citizenship status. We analyzed data from the childhood immunization supplement of the 2000-2003 National Health Interview Surveys (NHIS). Combined 4:3:1:3:3 immunization series completion by 18 months of age served as the dependent variable. Nested logistic regression models were estimated to examine relationship between parental nativity and timely immunization completion. Although socio-economic and health care access partially explained parental nativity, citizenship, and residential duration differences in timely completion, having a foreign-born mother was associated with a 14% reduced odds of completing the combined series on time when compared to children with US-born mothers net of covariates. Children of non-citizen mothers who had resided in the country for less than 5 years were the least likely to complete immunizations on time. The elimination of disparities in timely immunization completion among children requires special attention to children of newly arrived and non-citizen immigrants.

Individually Significant Risk Factors Do Not Provide an Accurate Clinical Prediction Rule for Infant Underimmunization in One Disadvantaged Urban Area

OBJECTIVE

To define a clinical prediction rule for underimmunization in children of low socioeconomic status.

METHODS

We assessed a cohort of 1160 infants born from July 1998 through June 1999 at an urban safety net hospital that received primary care at 4 community health centers. The main outcome measure was up-to-date status with the 3:2:2:2 infant vaccine series at 12 months of age.

RESULTS

Latino infants (n = 959, 83% of cohort) had immunization rates of 74%, at least 18% higher than any other racial/ethnic group. Multivariate logistic regression demonstrated the following independent associations (relative risk, 95% confidence interval) for inadequate immunization: non-Latino ethnicity (1.7, 1.4-2.0), maternal smoking (1.3, 1.1-1.7), no health insurance (1.9, 1.4-2.3), late prenatal care (1.9, 1.5-2.3), no pediatric chronic condition (2.1, 1.2-3.1), and no intent to breast-feed (1.3, 1.1-1.6). However, the index of concordance (c-index) for this model was only 0.69. Neither excluding infants who left the health care system nor accounting for infants who were "late starters" for their first vaccines improved the predictive accuracy of the model.

CONCLUSIONS

In this predominantly Latino population of low socioeconomic status, Latino infants have higher immunization rates than other infants. However, we were unable to develop a model to reliably predict which infants in this population were underimmunized. Models to predict underimmunization should be tested in other settings. In this population, interventions to improve immunization rates must be targeted at all children without respect to individual risk factors.

Immunization initiation among infants in the Oregon Health Plan

Infants who start receiving immunizations on time are more likely to be up to date at age 2 years. Among 39708 infants aged 3 months covered by the Oregon Health Plan (expanded Medicaid), those who did not have health care coverage within the first month of life were less likely to start receiving immunizations on time. Also at risk were infants in foster care, in subadoptive care, who were blind or disabled, who were Native American or Black, or whose mothers were not covered by the Oregon Health Plan.

Measles vaccine coverage and factors related to uncompleted vaccination among 18-month-old and 36-month-old children in Kyoto, Japan

BACKGROUND

Due to low vaccine coverage, Japan has not only experienced outbreaks of measles but has also been exporting it overseas. This study aims to survey measles vaccine coverage and the factors uncompleted vaccination among community-living children.

METHODS

Subjects were the parents whose children had undergone either an 18-month or a 36-month checkup publicly provided by Kyoto City during November 2001 to January 2002. An anonymous self-administered questionnaire survey was conducted.

RESULTS

The coverage was 73.2% among the 18-month-old children (n = 2707) and 88.9% among the 36-month-old children (n = 2340), respectively. The following characteristics of mothers were related to uncompleted measles vaccination: aged below 30, working, concerned about the adverse events of the vaccine, and had insufficient knowledge. Similarly, the following characteristics among children were related to uncompleted measles vaccination: not the first-born child, interacting with other children in group settings. The coverage was the lowest among the children whose mothers were concerned about the adverse events of the vaccine without proper knowledge of measles and its vaccination.

CONCLUSION

To increase vaccine coverage among children, parents' awareness about measles and vaccination against it should be promoted, especially for working mothers. Efforts to enhance access to vaccination services and to communicate with parents about changing vaccination schedules are necessary.

Determinants of vaccination after the Colombian health system reform

OBJECTIVE: To assess the effects of individual, household and healthcare system factors on poor children's use of vaccination after the reform of the Colombian health system. METHODS: A household survey was carried out in a random sample of insured poor population in Bogota, in 1999. The conceptual and analytical framework was based on the Andersen's Behavioral Model of Health Services Utilization. It considers two units of analysis for studying vaccination use and its determinants: the insured poor population, including the children and their families characteristics; and the health care system. Statistical analysis were carried out by chi-square test with 95% confidence intervals, multivariate regression models and Cronbach's alpha coefficient. RESULTS: The logistic regression analysis showed that vaccination use was related not only to population characteristics such as family size (OR=4.3), living area (OR=1.7), child's age (OR=0.7) and head-of-household's years of schooling (OR=0.5), but also strongly related to health care system features, such as having a regular health provider (OR=6.0) and information on providers' schedules and requirements for obtaining care services (OR=2.1). CONCLUSIONS: The low vaccination use and the relevant relationships to health care delivery systems characteristics show that there are barriers in the healthcare system, which should be assessed and eliminated. Non-availability of regular healthcare and deficient information to the population are factors that can limit service utilization.

Prevalence and correlates of high-quality basic pediatric preventive care

BACKGROUND

The list of recommended pediatric preventive services has grown considerably in the past decade, and clinician variability, clinician distribution, and other correlates of provision of these basic preventive services (BPS) are not known.

OBJECTIVE

To describe the proportion of high-quality basic pediatric preventive services, exclusive of immunizations, reported by parents and to identify sociodemographic and health system predictors and health service correlates of provision of these services.

STUDY DESIGN

The study used cross-sectional data on 2041 children, 4 to 35 months of age, in the 2000 National Survey of Early Childhood Health.

OUTCOME MEASURES

The BPS measure assesses the receipt of (1) developmental assessment, (2) injury prevention counseling, (3) screening for parental smoking, (4) guidance on reading to the child, and (5) guidance on 14 other topics (assessed as a composite score). The BPS scale categorizes the receipt of services as excellent, good, fair, or poor.

RESULTS

Most children received excellent (34.9%) or good (31.5%) care, but many received fair (24.9%) or poor (8.7%) care. Sociodemographic and health care factors such as race/ethnicity, insurance, and practice setting were not associated with BPS levels. Higher BPS scores were associated with parental reports of longer well-child visits, more counseling regarding family and community risk factors, lower rates of delayed or missed care, and greater satisfaction.

CONCLUSIONS

Two thirds of children receive good or excellent basic preventive care, as determined with this composite, and no disparities according to race/ethnicity, income, or health insurance status of families (which are often found to be associated with health care access) were found. This equitable distribution of high-quality care suggests a high level of clinician professionalism. Duration of visits may be a key factor to improve quality of care. Because of its association with other services, processes, and outcomes of care, the BPS scale may serve as a useful construct for monitoring quality and stimulating efforts to improve national pediatric preventive care.

Role of health insurance and a usual source of medical care in age-appropriate vaccination

OBJECTIVES

We examined the associations of having health insurance and having a usual source of medical care with age-appropriate childhood vaccination.

METHODS

Simulations were conducted with multivariate logistic regression models and a nationally representative sample of children to assess the likelihood of age-appropriate vaccination.

RESULTS

Simulated provision of health insurance and a usual source of medical care produced substantial increases in the likelihood of doses being received age-appropriately. Increases in the likelihood of a child's being up to date were also observed, but these increases typically were smaller than for age-appropriate vaccination.

CONCLUSIONS

Changes in childhood vaccination status should be assessed in age-appropriate terms, because measures of "up to date" status may not capture the effects of immunization interventions.

Underimmunization among children: effects of vaccine safety concerns on immunization status

OBJECTIVE

To examine the attitudes, beliefs, and behaviors of parents whose children were underimmunized with respect to > or =2 vaccines that have recently received negative attention, compared with parents whose children were fully immunized with respect to the recommended vaccines.

DESIGN

Case-control study.

SETTING

A sample of households that participated in the National Immunization Survey were recontacted in 2001.

MAIN OUTCOME MEASURE

Vaccination status was assessed. Case subjects were underimmunized with respect to > or =2 of 3 vaccines (diphtheria-tetanus-pertussis or diphtheria-tetanus-acellular pertussis, hepatitis B, or measles-containing vaccines), and control subjects were fully immunized.

RESULTS

The response rate was 52.1% (2315 of 4440 subjects). Compared with control households, case households were more likely to make 0 dollar to 30,000 dollars (adjusted odds ratio [OR]: 2.7; 95% confidence interval [CI]: 1.5-4.6) than at least 75,000 dollars, to have > or =2 providers (OR: 2.0; 95% CI: 1.3-3.1) than 1, and to have > or =4 children (OR: 3.1; 95% CI: 1.5-6.3) than 1 child. With control for demographic and medical care factors, case subjects were more likely than control subjects to not want a new infant to receive all shots (OR: 3.8; 95% CI: 1.5-9.8), to score vaccines as unsafe or somewhat safe (OR: 2.0; 95% CI: 1.2-3.4), and to ask the doctor or nurse not to give the child a vaccine for reasons other than illness (OR: 2.7; 95% CI: 1.2-6.1). Among case subjects, 14.8% of underimmunization was attributable to parental attitudes, beliefs, and behaviors.

CONCLUSIONS

Attitudes, beliefs, and behaviors indicative of vaccine safety concerns contribute substantially to underimmunization in the United States. Although concerns were significantly more common among parents of underimmunized children, many parents of fully immunized children demonstrated similar attitudes, beliefs, and behaviors, suggesting a risk to the currently high vaccination levels. Efforts to maintain and improve immunization coverage need to target those with attitudes/beliefs/behaviors indicative of vaccine safety concerns, as well as those with socioeconomic and health care access problems.

Risk factors for delay in age-appropriate vaccination

OBJECTIVE

To estimate the risk factors of children experiencing delay in age-appropriate vaccination using a nationally representative population of children, and to compare risk factors for vaccination delay with those based on up-to-date vaccination status models.

METHODS

The authors compared predictors of delay in age-appropriate vaccination with those for children who were not up-to-date, using a nationally representative sample of children from five years of pooled data (1992-1996) from the National Health Interview Survey (NHIS) Immunization Supplement. Duration of delay was calculated for the DTP4, Polio3, MMR1 doses and 4:3:1 series using age-appropriate vaccination standards; up-to-date status (i.e., whether or not a dose was received) was also determined. Adjusted odds ratios were estimated using multivariate logistic regression for models of vaccination delay and up-to-date vaccination status.

RESULTS

Absence of a two-parent household, large family size, parental education, Medicaid enrollment, absence of a usual provider, no insurance coverage, and households without a telephone were significantly related to increased odds of a child experiencing vaccination delay (p < or = 0.05).

CONCLUSIONS

Many of the risk factors observed in models of vaccination delay were not found to be significant in risk models based upon up-to-date status. Consequently, risk models of delays in age-appropriate vaccination may foster identification of children at increased risk for inadequate vaccination. Populations at increased risk of inadequate vaccination can be more clearly identified through risk models of delays in age-appropriate vaccination.

Effectiveness of individually tailored calendars in promoting childhood immunization in urban public health centers

OBJECTIVES

We examined the effectiveness of tailored calendars in increasing childhood immunization rates.

METHODS

Parents of babies aged birth to 1 year (n = 321) received individually tailored calendars promoting immunization from 2 urban public health centers. For each baby, an age- and sex-matched control was selected from the same center. Immunization status was tracked through age 24 months.

RESULTS

A higher proportion of intervention than of control babies were up to date at the end of a 9-month enrollment period (82% vs 65%, P <.001) and at age 24 months (66% vs 47%, P <.001). The younger the baby's age at enrollment in the program, the greater was the intervention effect.

CONCLUSIONS

Tailored immunization calendars can help increase child immunization rates.

Use of birth certificates and surveillance data to characterize reported pertussis among Texas infants and young children, 1995 to 2000

BACKGROUND

Pertussis morbidity is increasing, especially among young infants and children, who are more likely to be hospitalized and have more severe complications. Maternal and pediatric factors associated with underimmunization and hospitalization for pertussis are poorly understood, but young maternal age and low birth weight have been associated with pertussis among young infants.

METHODS

We used pertussis surveillance data, matching cases to the birth certificates of 416 Texas infants and children reported as pertussis cases during 1995 to 2000. Maternal/pediatric information gathered from birth certificates included birth weight, gestational age, and maternal factors (age, birthplace and education level, prenatal care, and previous live births). We assessed the immunization status of the cases and maternal/pediatric factors associated with underimmunization with a pertussis-containing vaccine and hospitalization using descriptive statistics and logistic regression.

RESULTS

The 416 cases represented 20% of the pertussis morbidity in Texas from 1995 through 2000. Most children had not been vaccinated (275 [66%]), even though 374 (90%) were old enough for at least one dose. Among those 374 children, only those younger than 6 months were associated with underimmunization (odds ratio [OR], 9.98; 95% confidence interval [CI], 6.24-15.97). Most patients (253 [61%]) were hospitalized. Hospitalization was associated with complications of apnea (OR, 2.13; 95% CI, 1.39 2.38), pneumonia (OR, 5.26; 95% CI, 2.94-11.59), and age younger than 6 months (OR, 2.11; 95% CI, 1.38-3.23).

CONCLUSION

More than two-thirds of the children reported as pertussis cases were old enough to have at least one dose of a pertussis-containing vaccine but were not immunized. Maternal and pediatric characteristics on birth certificates were not useful in predicting either underimmunization or hospitalization for pertussis complications. More current assessments of maternal and pediatric characteristics should be part of pertussis contact investigations.

[Why are some children incompletely vaccinated at the age of 2?]

OBJECTIVE

A survey was conducted in the Province of Quebec to document the factors associated with an incomplete immunization status among 2-year-old children.

METHODS

Parents of 430 completely and 266 partially vaccinated children selected from the computerized vaccination register agreed to participate.

RESULTS

The non-simultaneous administration of the 2nd MMR and 4th DPT-P-Hib at 18 months of age was responsible for 46% of incompleteness. The following characteristics were significantly associated with an incomplete immunization status: being a single parent, > or = 2 children in the family, an older age at first immunization (> or = 3 months), parent's preference for postponing the second vaccine when two injections are scheduled for the same visit, perception of lack of information about vaccination, and disagreement with immunization recommendations.

CONCLUSION

One of the key points of this study is the impact of the non-simultaneous administration of the two vaccines at 18 months. Factors such as being a single parent and older age at first immunization might be used to design an early intervention for children who are most likely to be incompletely immunized. Even if parents are favourable towards immunization, they need to be well informed about the associated risks and benefits.

[Why are some children incompletely vaccinated at the age of 2?]

OBJECTIVE

A survey was conducted in the Province of Quebec to document the factors associated with an incomplete immunization status among 2-year-old children.

METHODS

Parents of 430 completely and 266 partially vaccinated children selected from the computerized vaccination register agreed to participate.

RESULTS

The non-simultaneous administration of the 2nd MMR and 4th DPT-P-Hib at 18 months of age was responsible for 46% of incompleteness. The following characteristics were significantly associated with an incomplete immunization status: being a single parent, > or = 2 children in the family, an older age at first immunization (> or = 3 months), parent's preference for postponing the second vaccine when two injections are scheduled for the same visit, perception of lack of information about vaccination, and disagreement with immunization recommendations.

CONCLUSION

One of the key points of this study is the impact of the non-simultaneous administration of the two vaccines at 18 months. Factors such as being a single parent and older age at first immunization might be used to design an early intervention for children who are most likely to be incompletely immunized. Even if parents are favourable towards immunization, they need to be well informed about the associated risks and benefits.

A prenatal intervention study to improve timeliness of immunization initiation in Latino infants

This was a prospective randomized cohort study to assess the effectiveness of an educational immunization intervention with pregnant Latinas on timely initiation of infant immunization. Study participants were recruited from two community clinics in north San Diego County. A total of three hundred and fifty-two Latinas in the third trimester of pregnancy were recruited and randomly assigned to intervention or control groups. Participants received either a culturally and linguistically appropriate session on infant immunization (intervention) or a session on prevention of Sudden Infant Death Syndrome (control). The main outcome measures were pre-post immunization knowledge change and infant immunization status at 92 days. Immunization knowledge increased significantly in the intervention group [p < .0001, 95%CI (1.76, 2.47)]. No difference was found between groups in immunization series initiation: 95 percent of the children in the intervention group were up-to-date by 92 days from birth, and 93 percent of the control group was up-to-date at 92 days. The lack of significant association between receiving immunization education and infant immunization series initiation suggests that parent education may be necessary but not sufficient for timely immunization, particularly in clinics with effective well-child programs. Given the significant increase in immunization knowledge, the broader and perhaps more important implication is that language- and culturally specific infant health education messages in the prenatal period may have a positive long-term impact on the child's health and promote well-child care overall. Future studies should assess the role of prenatal well-child education in the context of clinics with low immunization levels.

Racial and ethnic disparities in the primary care experiences of children: a review of the literature

Substantial racial and ethnic disparities persist in children's health and use of health services in the United States. Although equitable access to primary care services is widely promoted as one of the most feasible remedies to reduce health disparities, there has only recently been an effort to assess its quality, particularly for children. Racial and socioeconomic differences in access to care have been previously well documented, but recent research has begun to elucidate differences in more qualitative experiences in the receipt of primary care. This article presents a synthesis and critique of the existing research according to the core attributes of primary care: first-contact care, longitudinality, comprehensiveness, and coordination. Finally, the article proposes an agenda for further research into the pathways by which racial and ethnic disparities in primary care exist.

Immunization registry-based recall for a new vaccine

BACKGROUND

Immunization recall for specific vaccines may be necessary to "catch up" children with newly available vaccines or recall children after vaccine shortages. The extent to which immunization registry-based recall can increase immunization rates for a new vaccine has not been prospectively studied.

OBJECTIVE

To assess the efficacy of letter/telephone recall for immunization with pneumococcal conjugate vaccine (PCV7) in an economically disadvantaged urban population.

DESIGN/METHODS

Randomized controlled trial at an inner-city teaching hospital. Using an immunization registry, we randomly assigned children aged 6 weeks to 22 months unimmunized for PCV7 to an intervention group (n = 610) or a control group (n = 624). The intervention consisted of letter and telephone recall for PCV7 vaccination. Two months after intervention, receipt of 1 or more doses of PCV7 was assessed. Intention-to-treat analysis was used.

RESULTS

We were unable to successfully contact 42.3% of the intervention subjects by mail and telephone. In the intervention group, 23.0% (140 children) received PCV7 within 2 months compared with 20.2% (126 children) in the control group (P = NS). No intervention effect was evident when children were stratified by age. A large proportion of the study population had Medicaid insurance (51.2%) or were uninsured (28.5%), but response to PCV7 recall did not vary by insurance status.

CONCLUSIONS

Letter and telephone recall for PCV7 vaccine did not significantly increase the rate of PCV7 immunization in an inner-city teaching hospital serving a disadvantaged population. The effectiveness of recall appears to have been limited by the inability to reach many subjects by mail and telephone.

The need for surveillance of delay in age-appropriate immunization

BACKGROUND

Vaccination status is assessed nationally in terms of up-to-date status without regard to the age at which recommended doses were actually received. Our study was conducted in 2000-2001 using the most current National Health Interview Survey (NHIS) public use files available.

METHODS

Retrospective analysis to determine up-to-date and age-appropriate vaccination status for children aged 25 to 72 months. Five years of pooled data (1992-1996) were obtained from the NHIS Immunization Supplement for children aged 25 to 72 months with immunization data based on written records. The outcome measures used were months of vaccination delay relative to age-appropriate vaccination standard as well as up-to-date vaccination status for the fourth diphtheria-tetanus-pertussis (DTP 4), Polio3, the first measles-mumps-rubella (MMR1) doses, and the 4:3:1 series.

RESULTS

Of the 9223 eligible children, 80% were up-to-date for the 4:3:1 vaccination series, but 48% had experienced delays relative to age-appropriate standards. For the DTP4 dose, 85% were up-to-date, although only 46% had received this dose at the appropriate age. Similarly, 90% of children were up-to-date with their Polio3 dose, with 64% receiving this dose at the appropriate age; 96% were up-to-date for the MMR1, and 58% received this dose at the appropriate age. Age-appropriate DTP4 vaccination increased by 17 percentage points from 1992 to 1996, whereas up-to-date DTP4 status increased by only 6% during the same period.

CONCLUSIONS

Children with up-to-date vaccination status often experienced considerable delay relative to age-appropriate vaccination standards. Consequently, vaccination status measures based solely on up-to-date status tend to understate the degree of underimmunization in a population. National surveillance of age-appropriate vaccination is necessary to identify subpopulations with the greatest prevalence of vaccination delay and to reveal underlying trends that may not be evident through assessments of up-to-date status.

The impact of income on children's and adolescents' preventive dental visits

INTRODUCTION

Limited information is available on the effect of income level on whether people visit a dentist for preventive care, whereas more has been written regarding the effect of income on "any" dental visits--which may include emergencies. Also, little is known of the effects of "near-poor" income (101 to 200 percent of the U.S. federal poverty level) on dental visits and preventive dental visits. The authors examined the impact of income at the "poor" and "near-poor" poverty levels on preventive dental visits made by children and adolescents.

METHODS

The authors used data from the 1996 Medical Expenditure Panel Survey for children and adolescents younger than 19 years of age to estimate the percentage of this group who had had preventive dental visits. They performed a multiple logistic regression analysis to adjust poverty levels by race and ethnicity, age and sex.

RESULTS

The distribution of preventive dental visits for those who were poor was similar to that for those who were near-poor, but the percentage distribution of preventive visits for children and adolescents with higher income was significantly different from that for those in the lower income groups. This was true across all the variables considered.

CONCLUSIONS

It is important to evaluate and monitor preventive care utilization trends for U.S. children and adolescents in the poor and near-poor categories separately, particularly in states that do not provide similar levels of access under the State Children's Health Insurance Program, or SCHIP. Enrollment of eligible children in Medicaid and SCHIP via oral health promotion outreach efforts, access to care and utilization of dental primary and secondary care services must be increased.

Prevalence and predictors of immunization among inner-city infants: a birth cohort study

CONTEXT

Although the proportion of US children who are appropriately immunized increased dramatically in the past decade, rates remain suboptimal among low-income, inner-city youth. Timely initiation of immunization is an important predictor of immunization status later in childhood; however, prospective studies identifying predictors of initiation are lacking.

OBJECTIVES

The objectives of this study were to: 1) describe immunization patterns in a cohort of infants born to predominantly low-income, inner-city mothers; 2) identify determinants, as measured at birth, of immunization status at 3 and 7 months of age; and 3) identify determinants of continuation of immunization among those who initiate immunization by 3 months of age.

DESIGN

Prospective, birth cohort study.

METHODS

Maternal/infant dyads were systematically selected from 3 District of Columbia hospitals between August 1995 and September 1996. Three hundred sixty-nine mothers were interviewed shortly after delivery, at 3 to 7 months postpartum, and at 7 to 12 months postpartum. Medical records were reviewed at all reported sites of care for 324 (88%) infants. Vaccinations assessed included diphtheria, tetanus, and pertussis; polio; and Haemophilus influenzae type B. Multivariate logistic regression analyses were used to determine factors associated with immunization status of infants at 3 and 7 months of age.

RESULTS

At 3 months of age, 75% of infants were up-to-date (UTD) versus only 41% at 7 months. In adjusted analyses, baseline factors associated with being UTD at 3 months included enrollment in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) during pregnancy, intention to breastfeed, and presence of the infant's grandmother in the household. Infants were less likely to be UTD if their mothers perceived higher barriers to immunization. Baseline factors associated with being UTD at 7 months included lower birth order and maternal employment. Among the subset of infants who were UTD at 3 months, only 53% remained UTD at 7 months. Factors measured at the first follow-up interview that were associated with continuation of immunization at 7 months included maternal employment and lower perceived barriers.

CONCLUSIONS

Immunization rates during the first 7 months of life were low in this inner-city population. Factors associated with immunization status that are potentially amenable to change included perceived barriers to immunization and enrollment in WIC during pregnancy.

The effect of different definitions of a patient on immunization assessment

OBJECTIVES

In this report, the authors compare immunization assessment using 2 definitions of a patient.

METHODS

Two Clinical Assessment Software Application (CASA) assessments were performed. The first sampled 200 two-year-olds seen at least once since birth. The second sampled 200 two-year-olds seen in the previous year. Children with incomplete immunizations in the first sample were contacted.

RESULTS

In the second sample, 72% of children had complete immunizations, compared with 46% in the first sample. In the first sample, 78% of children with incomplete immunizations had not been seen during the past year. Of 134 children in the first sample seen in the past year or successfully contacted, 75% had complete immunizations.

CONCLUSIONS

The CASA assessment's definition of a patient underestimates immunization rates.

A simple provider-based educational intervention to boost infant immunization rates: a controlled trial

We sought to determine if a simple educational intervention initiated at the first well-child care visit, with reinforcement at subsequent visits, can improve inner-city infant immunization rates. We conducted a controlled trial involving 315 newborn infants and their primary caregivers in 3 inner-city primary care centers. Child health care providers gave caregivers in the intervention group an interactive graphic card with verbal reinforcement. At later visits, stickers were applied to the card when immunizations were given. Routine information was given to controls. After the trial, age-appropriate immunization rates at 7 months were 58% in each group. Intervention infants had 50% fewer missed opportunities to immunize (p=0.01) but cancelled 77% more appointments (p=0.04) than controls. We conclude that a brief educational intervention at the first well-child care visit did not boost 7-month immunization rates, although it was associated with fewer missed opportunities to immunize.

Effects of medicaid managed care on quality: childhood immunizations

BACKGROUND

Underimmunization is distributed unevenly across populations, concentrated among the impoverished. Managed care has stimulated the development of quality indicators such as immunization rates to assess health status of populations.

OBJECTIVE

To determine if enrollment in Medicaid managed care (MMC) improves quality of health care as reflected by immunization rates when compared with fee-for-service Medicaid (FFSM). DESIGN. Prospective cohort study of infants born between May 1994 and April 1995 with a 24-month follow-up period.

SETTING

Urban teaching hospital and surrounding ambulatory settings.

PARTICIPANTS

Consecutive sample of infants (n = 644) enrolled in MMC or FFSM. Ninety-two percent of eligible patients were enrolled, and 87% completed follow-up.

MAIN OUTCOME MEASURE

Up-to-date immunization status.

RESULTS

Seventy-three percent of the MMC and 72.4% of the FFSM patients were up-to-date on their immunizations: relative risk 1.01, (95% confidence interval [CI] 0.87, 1.17). No differences were found in age at immunization between the MMC and FFSM groups. After adjusting for other factors in multivariate analysis, insurance status remained unassociated with immunization status: adjusted odds ratio (OR) 1.04, (95% CI: 0.90, 1.10). Factors associated with up-to-date immunization included firstborn child, OR 2.28 (95% CI: 1.45, 3.60) and adequate maternal prenatal care, OR 2.24 (95% CI: 1.44, 3.48). Variables characterizing children less likely to be adequately immunized included father living in home with child, OR 0.53 (95% CI: 0.33, 0.85) and using private office-based primary care, OR 0.39 (95% CI: 0.23, 0.63).

CONCLUSIONS

Enrollment in MMC did not improve rates of immunizations when compared with FFSM.

Evaluating the State Children's Health Insurance Program: critical considerations

The Balanced Budget Act of August 1997 was intended to improve the insurance coverage of low-income children. Although no specific mandates for evaluation accompanied the legislation, states are expected to assess its impact. Insurance improves access to and use of health services. The extent to which this is associated with better health depends on the kinds of services received. Access to a regular source of care is a critical characteristic. If this source of care provides good primary care, a variety of benefits would be expected to accrue. Thus, evaluation of the benefits of the State Children's Health Insurance Program should address not only improved coverage by health insurance for eligible children, but also the extent to which children receive high-quality primary care, including appropriate referrals when needed. Maternal access to and use of services is also a critical factor. Targets for evaluation include state activities to (a) enroll through outreach, inform through education, and develop information systems for tracking; (b) assess the degree of penetration of insurance among low-income children and their mothers, the availability of health care personnel, and the adequacy of benefits conferred by the insurance, primary-care services, and back-up specialty services; and (c) obtain evidence of improved health status. This article details approaches that can appropriately be used to address each of these aspects of concern.

Exposure to immunization media messages among African American parents

BACKGROUND

African Americans have low immunization rates, yet little is known about their immunization knowledge, attitudes, and practices or about the effect of outreach to this audience. In Spring 1997, the California Department of Health Services (CDHS) launched a statewide culturally sensitive and ethnically specific media campaign directed toward African Americans. This campaign was preceded by a major Los Angeles County Department of Health Services media campaign.

OBJECTIVES

The objectives of this study were to (a) estimate exposure to immunization media messages among African Americans; (b) determine sources of immunization information; and (c) assess various immunization attitudes and beliefs in order to refine future outreach efforts.

METHODS

Following the CDHS media campaign, a random digit dial survey was conducted with 801 African American families with children under age 10. The sample was drawn from the four California regions with the highest African American birth rates. It included all zip codes in these regions with greater than 150 African American births per year. Lower bound response rates ranged from 62.5 to 76.1%. Higher income and education levels were overrepresented. Results were weighted to adjust for this.

RESULTS

Over 88% remembered seeing or hearing some form of immunization information. Exposure to television ads was reported by 63% followed by billboards (51%) and radio (42%). Sixty-two percent thought mild disease was possible after shots; 27% feared HIV from needles and 19% thought pain was a barrier. Respondents who cited money as a barrier (26%) were less likely to believe that shots were available for free (P = 0.02).

CONCLUSIONS

Media advertising is an effective tool for reaching African Americans. Addressing specific concerns (e.g., clarification of the circumstances and likelihood of getting a mild case of the disease following an immunization, availability of free shots, and risk of HIV) may contribute to increased immunization rates for this population.

Low immunisation uptake: is the process the problem?

OBJECTIVE

To examine mothers' satisfaction with the process of immunisation and its possible contribution to suboptimal immunisation uptake.

DESIGN

In depth interviews with mothers.

SETTING

Two Community Care Areas, Dublin city, Ireland.

PARTICIPANTS

In depth interviews of 23 mothers of children 1-2 years old, recruited purposively from a birth cohort born in 1994.

MAIN RESULTS

Mothers preferred general practice to Health Centre immunisation (11:5) for predominantly emotional compared with practical reasons (4:1). Health Centre immunisation was seen, at times, as unacceptably rough and inhuman. Many mothers experienced severe emotional distress at the prospect of inflicting the pain of immunisation on their babies. The non-empathic stance of some immunising doctors was unacceptable to mothers. They valued attempts by health professionals to acknowledge the pain of immunisation and to engage with their baby. Adverse experiences contributed to deferral of future visits and to defaulting behaviour.

CONCLUSIONS

Low empathy mass immunisation in clinic type settings may be unacceptable to mothers in the 1990s, and may in part explain suboptimal uptake in health care systems that use such clinics.

Immunization coverage among predominantly Hispanic children, aged 2-3 years, in central Los Angeles

PURPOSE

To assess the immunization status of young children in a predominantly Hispanic region in and around downtown Los Angeles, and factors associated with complete immunization by age 24 months.

METHODS

The information was gathered in a two-stage cluster survey with probability proportionate to estimated size (PPS) sampling of 30 clusters at the first stage, and simple random sampling of a constant number of children at the second stage. Vaccination coverage was determined by a review of the home immunization (HI) card, or of clinic records.

RESULTS

Of the 270 sampled children, 91.5% were Hispanic and 6.7% were Black. Home telephone numbers were not available in 24.8% of the homes, and 34.1% reported having no health insurance. Vaccination coverage was over 90% for the first three doses of Diphtheria, tetanus toxoids and pertussis/ diphtheria, tetanus toxoids and acellular pertussis vaccine (DTP/DTaP)/Diphtheria and tetanus toxoids vaccine (DT), first two doses of poliovirus (Polio) vaccine, first dose of measles, mumps and rubella (MMR) vaccine, and first two doses of hepatitis B (Hep B) vaccine. Yet, by age 24 months, only 72.2% of the children had received the combined series of 4:3:1 (i.e., four DTP/DTaP/DT, three Polio, one MMR). This was further reduced to 64.4% for the combined series of 4:3:1:3:3 (i.e., four DTP/DTaP/ DT, three Polio, one MMR, three Haemophilus influenzae type b (Hib), three Hep B). Factors associated with completed on-time vaccination were having an HI card available during the interview and being enrolled in Supplemental Nutrition Program for Women, Infants and Children (WIC).

CONCLUSIONS

While vaccination levels for individual antigens were found to be high, more emphasis needs to be placed on getting preschool children vaccinated on-time according to the Recommended Childhood Immunization Schedule.

Immunization status of children enrolled in a hospital-based medicaid managed care practice: the importance of the timing of vaccine administration

OBJECTIVES

To evaluate the immunization status of children enrolled in a hospital-based Medicaid managed care practice and to assess the impact of the timing of vaccine administration on measured immunization rates.

DESIGN AND METHODS

The medical records of all children between the ages of 19 and 35 months who were continuously enrolled in the Medicaid managed care practice for the last 6 months of 1996 were reviewed. Immunization status was determined for the following vaccines: diphtheria-tetanus-pertussis/diphtheria-tetanus-acellular pertussis (4 doses); Haemophilus influenzae type b (3 doses); poliovirus (3 doses); hepatitis B (3 doses); measles-mumps-rubella (1 dose); and overall for the basic series. Two assessment methods were used to determine the immunization status of the study children: (1) a count of all documented vaccines ("count"); and (2) only including vaccines that met minimal age and spacing intervals based on American Academy of Pediatrics and CDC recommendations ("interval assessment").

RESULTS

With the count method vaccine-specific immunization rates ranged from 88 to 95%, with overall coverage of 80% for the basic series. With the interval assessment method vaccine-specific immunization rates ranged from 74 to 92%, with overall coverage of 53% for the basic series.

CONCLUSIONS

When all documented vaccines were included in the assessment, vaccine-specific immunization rates approached national goals, although overall coverage remained below 90% in this Medicaid managed care practice. The substantially lower immunization rates obtained by the interval assessment method demonstrate the importance of considering the issue of vaccine timing when interpreting immunization rates and the need for policies for revaccinating children who were immunized at less than recommended intervals. The results also have implications for provider education regarding the early administration of vaccines.