Methods to systematically review and meta-analyse observational studies: a systematic scoping review of recommendations

The evidence for improving balance by strengthening the toe flexor muscles: A systematic review

BACKGROUND

Poor postural balance in the upright position is strongly correlated to morbidities, such as falls in older adult populations and to lower limb injuries in the younger populations. Good postural balance depends on muscular strength and the integration of neurological and muscular feedback mechanisms throughout the body. Since the interface with the ground is the plantar surface of each foot, an improved understanding of the role of foot muscles in postural balance is warranted.

RESEARCH QUESTION

Does improved toe flexor strength result in better postural balance, across the lifespan?

METHODS

A systematic review was conducted of papers from 1900 to 2019 inclusive, from five databases. Inclusion and exclusion criteria were established prior to selection. Inclusion criteria were: observational and longitudinal studies, healthy subjects, at least one balance and one toe flexor strength test conducted. Exclusion criteria were: subjects with a pathology/disability, case study, systematic or literature review. Two examiners assessed a study's suitability for inclusion in this review, based on the above criteria. Study quality was assessed using the Critical Appraisal Skills Program Tools. The type of studies and methodological heterogeneity precluded the feasibility of conducting a meta-analysis.

RESULTS

Nine studies were included. In each study, participants were over sixty years of age, and over 73 % of them were female. No study was found for a younger population group. There were seven cross-sectional studies, two randomized control trials and there was one case-control study. All studies provided evidence of directly proportional, clinically significant correlations between toe flexor strength and postural balance.

SIGNIFICANCE

Toe flexor strength contributes to improved postural balance for people over the age of 60. Research is needed to establish the relationship between foot muscle strength and balance in younger adults and children.

Identification and prevalence of frailty in diabetes mellitus and association with clinical outcomes: a systematic review protocol

INTRODUCTION

Diabetes mellitus is common and growing in prevalence, and an increasing proportion of people with diabetes are living to older age. Frailty is, therefore, becoming an important concept in diabetes. Frailty is associated with older age and describes a state of increased susceptibility to decompensation in response to physiological stress. A range of measures have been used to quantify frailty. This systematic review aims to identify measures used to quantify frailty in people with diabetes (any type); to summarise the prevalence of frailty in diabetes; and to describe the relationship between frailty and adverse clinical outcomes in people with diabetes.

METHODS AND ANALYSIS

Three electronic databases (Medline, Embase and Web of Science) will be searched from 2000 to November 2019 and supplemented by citation searching of relevant articles and hand searching of reference lists. Two reviewers will independently review titles, abstracts and full texts. Inclusion criteria include: (1) adults with any type of diabetes mellitus; (2) quantify frailty using any validated frailty measure; (3) report the prevalence of frailty and/or the association between frailty and clinical outcomes in people with diabetes; (4) studies that assess generic (eg, mortality, hospital admission and falls) or diabetes-specific outcomes (eg, hypoglycaemic episodes, cardiovascular events, diabetic nephropathy and diabetic retinopathy); (5) cross-sectional and longitudinal observational studies. Study quality will be assessed using the Newcastle-Ottawa Scale for observational studies. Clinical and methodological heterogeneity will be assessed, and a random effects meta-analysis performed if appropriate. Otherwise, a narrative synthesis will be performed.

ETHICS AND DISSEMINATION

This manuscript describes the protocol for a systematic review of observational studies and does not require ethical approval.

PROSPERO REGISTRATION NUMBER

CRD42020163109.

The association between road traffic noise and myocardial infarction: A systematic review and meta-analysis

This systematic review and meta-analysis study aimed to investigate the association between exposure to road traffic noise (RTN) and myocardial infarction (MI). Of 681 studies found by searching in databases, including Scopus, Web of Science, Embase, and PubMed on November 29, 2019, the number of 13 studies, including seven cohort, five case-control, and one cross-sectional studies with 1,626,910 participants and 45,713 cases of MI was included. The pooled relative risk (RR) and 95% confidence interval (CI) of MI were calculated using a random-effect model across studies. Heterogeneity measures by reporting the I-square index. Subgroup analysis according to the designs and sensitivity analysis based on the Jackknife approach was performed. We observed in the eight studies the association was investigated in different noise exposure groups and in the 10 studies (including two conference papers) the risk of MI was provided per specific unit increment of RTN. We ran two independent types of meta-analyses involving a categorical analysis (comparing the highest and the lowest category of noise exposure groups) and an exposure-response analysis (the risk of MI per 10-dB increment of RTN). The pooled RR (95% CI) of MI for the categorical and exposure-response meta-analyses was calculated 1.03 (0.93, 1.13) and 1.02 (1.00, 1.05), respectively. For both types of meta-analyses, subgroup analysis indicates a significant association in the studies with case-control and cross-sectional designs but not cohort studies. For the exposure-response meta-analysis, a significantly greater risk of MI was observed after excluding the two conference papers (RR = 1.03 and 95% CI = 1.00, 1.05) and by further excluding the studies provided originally the risk of MI only for the categorical analysis (RR = 1.02 and 95% CI = 1.01, 1.03). We did not show a significant publication bias across studies. In conclusion, our study suggests a significant odds of association between exposure to RTN and the risk of MI.

Quality of life outcomes for people with serious mental illness living in supported accommodation: systematic review and meta-analysis

PURPOSE

To conduct a systematic review and meta-analysis of quality of life (QoL) outcomes for people with serious mental illness living in three types of supported accommodation.

METHODS

Studies were identified that described QoL outcomes for people with serious mental illness living in supported accommodation in six electronic databases. We applied a random-effects model to derive the meta-analytic results.

RESULTS

13 studies from 7 countries were included, with 3276 participants receiving high support (457), supported housing (1576) and floating outreach (1243). QoL outcomes related to wellbeing, living conditions and social functioning were compared between different supported accommodation types. Living condition outcomes were better for people living in supported housing ([Formula: see text]= - 0.31; CI = [- 0.47; - 0.16]) and floating outreach ([Formula: see text]= - 0.95; CI = [- 1.30; - 0.61]) compared to high-support accommodation, with a medium effect size for living condition outcomes between supported housing and floating outreach ([Formula: see text]= - 0.40; CI = [- 0.82; 0.03]), indicating that living conditions are better for people living in floating outreach. Social functioning outcomes were significant for people living in supported housing compared to high support ([Formula: see text] = - 0.37; CI = [- 0.65; - 0.09]), with wellbeing outcomes not significant between the three types of supported accommodation.

CONCLUSION

There is evidence that satisfaction with living conditions differs across supported accommodation types. The results suggest there is a need to focus on improving social functioning and wellbeing outcomes for people with serious mental illness across supported accommodation types.

Can MRI differentiate between atypical cartilaginous tumors and high-grade chondrosarcoma? A systematic review

Background and purpose - Adequate staging of chondroid tumors at diagnosis is important as it determines both treatment and outcome. This systematic review provides an overview of MRI criteria used to differentiate between atypical cartilaginous tumors (ACT) and high-grade chondrosarcoma (HGCS).Patients and methods - For this systematic review PubMed and Embase were searched, from inception of the databases to July 12, 2018. All original articles describing MRI characteristics of pathologically proven primary central chondrosarcoma and ACT were included. A quality appraisal of the included papers was performed. Data on MRI characteristics and histological grade were extracted by 2 reviewers. Meta-analysis was performed if possible. The study is registered with PROSPERO, CRD42018067959.Results - Our search identified 2,132 unique records, of which 14 studies were included. 239 ACT and 140 HGCS were identified. The quality assessment showed great variability in consensus criteria used for both pathologic and radiologic diagnosis. Due to substantial heterogeneity we refrained from pooling the results in a meta-analysis and reported non-statistical syntheses. Loss of entrapped fatty marrow, cortical breakthrough, and extraosseous soft tissue expansion appeared to be present more often in HGCS compared with ACT.Interpretation - This systematic review provides an overview of MRI characteristics used to differentiate between ACT and HGCS. Future studies are needed to develop and assess more reliable imaging methods and/or features to differentiate ACT from HGCS.

Quantification of risk factors for bovine viral diarrhea virus in cattle herds: A systematic search and meta-analysis of observational studies

Bovine viral diarrhea virus (BVDV) is endemic in many parts of the world, and multiple countries have implemented surveillance activities for disease control or eradication. In such control programs, the disease-free status can be compromised by factors that pose risks for introduction or persistence of the virus. The aim of the present study was to gain a comprehensive overview of possible risk factors for BVDV infection in cattle herds in Europe and to assess their importance. Papers that considered risk factors for BVDV infection in cattle were identified through a systematic search. Further selection of papers eligible for quantitative analysis was performed using a predefined checklist, including (1) appropriate region (i.e., studies performed in Europe), (2) representativeness of the study population, (3) quality of statistical analysis, and (4) availability of sufficient quantitative data. In total, 18 observational studies were selected. Data were analyzed by a random-effects meta-analysis to obtain pooled estimates of the odds of BVDV infection. Meta-analyses were performed on 6 risk factors: herd type, herd size, participation in shows or markets, introduction of cattle, grazing, and contact with other cattle herds on pasture. Significant higher odds were found for dairy herds (odds ratio, OR = 1.63, 95% confidence interval, CI: 1.06-2.50) compared with beef herds, for larger herds (OR = 1.04 for every 10 extra animals in the herd, 95% CI: 1.02-1.06), for herds that participate in shows or markets (OR = 1.45, 95% CI: 1.10-1.91), for herds that introduced cattle into the herd (OR = 1.41, 95% CI: 1.18-1.69), and for herds that share pasture or have direct contact with cattle of other herds at pasture (OR = 1.32, 95% CI: 1.07-1.63). These pooled values must be interpreted with care, as there was a high level of heterogeneity between studies. However, they do give an indication of the importance of the most frequently studied risk factors and can therefore assist in the development, evaluation, and optimization of BVDV control programs.

Cancer-related Fatigue in Breast Cancer Survivors: A Review

Fatigue has been the most distressing and frequent symptom in breast cancer (BC) survivors after treatment. Although fatigue can occur in other cancer survivors, women with a history of BC might share some distinctive features. The present study aimed to recapitulate the knowledge about risk factors and correlates of cancer-related fatigue (CRF) in BC survivors after oncologic therapy. An electronic data search was conducted in PubMed using the terms "fatigue," "breast," "cancer," and "survivors." Records were included if they were original articles, available in English, had used a quantitative scale, had > 100 participants, and had excluded women with BC relapse. BC survivors were required to have finished their treatments ≥ 2 months before, except for hormonal therapy. The physiopathology and other interventions were considered beyond the scope of our review. The correlates were subsequently classified into 7 main categories: (1) sociodemographic data, (2) physical variables, (3) tumor- and treatment-related variables, (4) comorbidities, (5) other symptoms, (6) psychological issues, and (7) lifestyle factors. Fatigue was consistently greater in younger, obese, and diabetic women. Women reporting fatigue often communicated symptoms such as pain, depression, insomnia, and cognitive dysfunction. Coping strategies such as catastrophizing could play an important role in the persistence of fatigue. However, tumor characteristics, previous treatments received, and physical activity were not consistently reported. CRF was a strong predictor of the quality of life of BC survivors after treatment. In conclusion, we found CRF was a frequent and serious symptom that severely affects the quality of life of BC survivors after treatment. Health practitioners require more awareness and information about CRF.

Subclinical atherosclerosis is associated with incident atrial fibrillation: a systematic review and meta-analysis

Aims

Coronary artery disease is an established risk factor for incident atrial fibrillation (AF), but it is unclear whether subclinical atherosclerosis also increases the risk of incident AF. Therefore, the aim was to assess the association between subclinical atherosclerosis, defined by increased carotid intima-media thickness (cIMT) or coronary artery calcium score (CACS), and incident AF.

Methods and results

A systematic review of MEDLINE, EMBASE, and Cochrane was done to find all cohort studies investigating the association between subclinical atherosclerosis, defined by increased cIMT or CACS, and incident AF. Eligible articles had to be available in an English full-text version; include adults over the age of 18 years; include ≥100 participants; and have a follow-up period ≥12 months. Data on cIMT were pooled using a fixed-effects model, while data on CACS (I2 >25) were pooled using a random-effects model. Five studies on cIMT including 36 333 patients and two studies on CACS including 34 603 patients were identified. All studies investigating the association between increased cIMT and incident AF showed a significant association, with an overall hazard ratio (HR) of 1.43 [95% confidence interval (CI) 1.27–1.59]. The two studies investigating the association between increased CACS and AF also showed a significant association with an overall HR of 1.07 (95% CI 1.02–1.12).

Conclusion

Data from seven observational studies suggest that subclinical atherosclerosis defined by increased cIMT or CACS is associated with an increased risk of incident AF. These findings emphasize the need for further research investigating whether treatment of subclinical atherosclerosis should be a part of the initiatives to prevent AF.

Systematic review of the prospective association of daily step counts with risk of mortality, cardiovascular disease, and dysglycemia

BACKGROUND

Daily step counts is an intuitive metric that has demonstrated success in motivating physical activity in adults and may hold potential for future public health physical activity recommendations. This review seeks to clarify the pattern of the associations between daily steps and subsequent all-cause mortality, cardiovascular disease (CVD) morbidity and mortality, and dysglycemia, as well as the number of daily steps needed for health outcomes.

METHODS

A systematic review was conducted to identify prospective studies assessing daily step count measured by pedometer or accelerometer and their associations with all-cause mortality, CVD morbidity or mortality, and dysglycemia (dysglycemia or diabetes incidence, insulin sensitivity, fasting glucose, HbA1c). The search was performed across the Medline, Embase, CINAHL, and the Cochrane Library databases from inception to August 1, 2019. Eligibility criteria included longitudinal design with health outcomes assessed at baseline and subsequent timepoints; defining steps per day as the exposure; reporting all-cause mortality, CVD morbidity or mortality, and/or dysglycemia outcomes; adults ≥18 years old; and non-patient populations.

RESULTS

Seventeen prospective studies involving over 30,000 adults were identified. Five studies reported on all-cause mortality (follow-up time 4-10 years), four on cardiovascular risk or events (6 months to 6 years), and eight on dysglycemia outcomes (3 months to 5 years). For each 1000 daily step count increase at baseline, risk reductions in all-cause mortality (6-36%) and CVD (5-21%) at follow-up were estimated across a subsample of included studies. There was no evidence of significant interaction by age, sex, health conditions or behaviors (e.g., alcohol use, smoking status, diet) among studies that tested for interactions. Studies examining dysglycemia outcomes report inconsistent findings, partially due to heterogeneity across studies of glycemia-related biomarker outcomes, analytic approaches, and sample characteristics.

CONCLUSIONS

Evidence from longitudinal data consistently demonstrated that walking an additional 1000 steps per day can help lower the risk of all-cause mortality, and CVD morbidity and mortality in adults, and that health benefits are present below 10,000 steps per day. However, the shape of the dose-response relation is not yet clear. Data are currently lacking to identify a specific minimum threshold of daily step counts needed to obtain overall health benefit.

Biomarker roles identification of miR-106 family for predicting the risk and poor survival of colorectal cancer

Background

Recent studies have extensively investigated the roles of miR-106 in colorectal cancer (CRC). However, the associations and molecular mechanism underlying the roles of miR-106 in CRC remain unclear. We aimed to thoroughly investigate the biomarker roles of miR-106 for predicting the risk and survival outcome in CRC.

Methods

We first conducted a comprehensive meta-analysis to quantitatively evaluate the roles of miR-106 in the diagnosis and prognosis of CRC. Then, we qualitatively explored the biomarker roles of miR-106 in CRC through an integrative bioinformatics analysis.

Results

The results indicated that miR-106 yielded a combined AUC of 0.79 (95% CI: 0.76–0.83), with a pooled sensitivity of 0.50 (95% CI: 0.32–0.68) and a pooled specificity of 0.93 (95% CI: 0.79–0.98) for discriminating CRC cases from normal controls. Moreover, patients with higher expression of miR-106 were significantly associated with shorter disease-free survival (HR: 1.73; 95%CI: 1.23–2.44) and overall survival (HR: 1.39; 95%CI: 1.09–1.77). Finally, gene ontology and pathway analysis demonstrated that miR-106 family was highly involved in the initiation and progression of CRC and indicated the potential molecular mechanism for miR-106 in CRC.

Conclusions

Our results indicated that miR-106 showed promising potential as diagnostic and prognostic biomarker for CRC. Nevertheless, the underlying molecular mechanism of miR-106 family involved in CRC requires further investigation.

Morbid exercise behaviour and eating disorders: A meta-analysis

BACKGROUND AND AIMS

This study examined the relationship between self-reported symptoms of morbid exercise behaviour (MEB) and eating disorders (ED) using meta-analytic techniques.

METHODS

We systematically searched MEDLINE, PsycINFO, Web of Science, SciELO and Scopus. Random effects models were used to compute pooled effect sizes estimates (r). The robustness of the summarized estimates was examined through sensitivity analyses by removing studies one at a time.

RESULTS

Sixty-six studies comprising 135 effect-sizes (N = 21,816) were included. The results revealed: (a) small-sized relationship in the case of bulimic symptoms (r = 0.19), (b) small- (r = 0.28) to medium-sized relationships (r = 0.41) in the case of body/eating concerns, and (c) medium-sized relationships in the case of overall ED symptoms (r = 0.35) and dietary restraint (r = 0.42). Larger effect sizes were observed in the case of overall ED symptoms in clinical, younger, and thinner populations, as well as when employing a continuously-scored instrument for assessing ED or the Compulsive Exercise Test for assessing MEB. Larger effect sizes were also found in female samples when the ED outcome was dietary restraint.

CONCLUSIONS

The identified gaps in the literature suggest that future research on the topic may benefit from: (a) considering a range of clinical (in terms of diagnosed ED) and non-clinical populations from diverse exercise modalities, (b) addressing a wide range of ED symptomatology, and (c) employing longitudinal designs that clarify the temporal direction of the relationship under consideration.

Reproducibility of individual effect sizes in meta-analyses in psychology

To determine the reproducibility of psychological meta-analyses, we investigated whether we could reproduce 500 primary study effect sizes drawn from 33 published meta-analyses based on the information given in the meta-analyses, and whether recomputations of primary study effect sizes altered the overall results of the meta-analysis. Results showed that almost half (k = 224) of all sampled primary effect sizes could not be reproduced based on the reported information in the meta-analysis, mostly because of incomplete or missing information on how effect sizes from primary studies were selected and computed. Overall, this led to small discrepancies in the computation of mean effect sizes, confidence intervals and heterogeneity estimates in 13 out of 33 meta-analyses. We provide recommendations to improve transparency in the reporting of the entire meta-analytic process, including the use of preregistration, data and workflow sharing, and explicit coding practices.

Challenges in meta-analyses with observational studies

OBJECTIVE

Meta-analyses of observational studies are frequently published in the literature, but they are generally considered suboptimal to those involving randomised controlled trials (RCTs) only. This is due to the increased risk of biases that observational studies may entail as well as because of the high heterogeneity that might be present. In this article, we highlight aspects of meta-analyses with observational studies that need more careful consideration in comparison to meta-analyses of RCTs.

METHODS

We present an overview of recommendations from the literature with respect to how the different steps of a meta-analysis involving observational studies should be comprehensively conducted. We focus more on issues arising at the step of the quantitative synthesis, in terms of handling heterogeneity and biases. We briefly describe some sophisticated synthesis methods, which may allow for more flexible modelling approaches than common meta-analysis models. We illustrate the issues encountered in the presence of observational studies using an example from mental health, which assesses the risk of myocardial infarction in antipsychotic drug users.

RESULTS

The increased heterogeneity observed among studies challenges the interpretation of the diamond, while the inclusion of short exposure studies may lead to an exaggerated risk for myocardial infarction in this population.

CONCLUSIONS

In the presence of observational study designs, prior to synthesis, investigators should carefully consider whether all studies at hand are able to answer the same clinical question. The potential for a quantitative synthesis should be guided through examination of the amount of clinical and methodological heterogeneity and assessment of possible biases.

Clinical forensic medicine in Eastern Denmark: Organisation and assessments

Internationally, clinical forensic medicine (CFM) is diverse in content and conduct, and forensic medical methods are not always evidence based. The first step towards evidence-based practice is to achieve a thorough knowledge of international diversity, which necessitates that CFM practitioners provide information about their national practice. This paper’s aim is to describe the organisation of CFM in Denmark, exemplified by the set-up in Eastern Denmark, and the types of assessments performed. In Denmark, forensic medicine is a board-certified specialty under the health authorities, with mandatory qualifications. The Danish Accreditation Fund accredits the Departments of Forensic Medicine as inspection bodies, according to an international European standard that is approved by Danish Standards. Mainly at police request, forensic doctors perform examinations of both victims and suspected perpetrators of perilous crimes. The examinations’ purposes are documentation and assessment of the findings and collection of biological evidence. The clinical forensic examinations do not include any treatment or medical follow-up. Thus, the forensic doctors must be neutral, objective and impartial. The clinical forensic examinations provide documentation of findings and conclusions not otherwise available for the police investigation and legal aftermath. Moreover, the accredited, standardised protocols ensure that the Departments of Forensic Medicine meet their obligations as inspection bodies, thus ensuring public confidence in the departments’ services.

Correlates of sedentary behaviour in Asian adults: A systematic review

The objective of this study is to systematically review the evidence on correlates of sedentary behaviour (SB) among Asian adults. We searched for studies that examined individual, environmental, and political/cultural correlates of total and domain-specific SB (transport, occupation, leisure, and screen time) in Asian adults published from 2000 onwards in nine scientific databases. Two reviewers independently screened identified references. Following quality assessment of included studies, we performed narrative synthesis that considered differences based on SB measurements, regions, and population characteristics (PROSPERO: CRD42018095268). We identified 13 249 papers of which we included 49, from four regions and 12 countries. Researchers conducted cross-sectional analyses and most relied on SB self-report for SB measurement. Of the 118 correlates studied, the following associations were consistent: higher age, living in an urban area (East Asia), and lower mental health with higher total SB; higher education with higher total and occupational SB; higher income with higher leisure-time SB; higher transit density with higher total SB in older East Asians; and being an unmarried women with higher SB in the Middle East. We encourage more research in non-high-income countries across regions, further exploration of important but neglected correlates using longitudinal designs and qualitative research, and the use of objective instruments to collect SB data.

Social and Economic Factors and Malnutrition or the Risk of Malnutrition in the Elderly: A Systematic Review and Meta-Analysis of Observational Studies

Malnutrition in the elderly could be tackled by addressing socioeconomic factors. This study aimed to determine the magnitude of the relationship between socioeconomic factors and the malnutrition or malnutrition risk (MR) in the elderly. The PubMed and SCOPUS databases were searched for observational studies that included assessment of malnutrition or/and MR and socioeconomic variables (educational level, living alone, marital status, income and occupational level, feeling of loneliness, place of residence, and food expenditure) in ≥60-year-old subjects, published in English among 2000–2018 (PROSPERO: CRD42019137097). The systematic review included 40 observational studies (34 cross-sectional and 4 cohort studies) and 16 cross-sectional studies in the meta-analysis (34,703 individuals) of malnutrition and MR in relation to low educational level (Odds Ratio (OR): 1.48; 95% Confidence Interval (CI): 1.33–1.64; p < 0.001), living alone (OR: 1.92; 95% CI: 1.73–2.14; p < 0.001), being single, widowed, or divorced (OR: 1.73; 95% CI: 1.57–1.90; p < 0.001), and low income level (OR: 2.69; 95% CI: 2.35–3.08; p < 0.001), and considering these four socioeconomic factors, malnutrition and MR is associated with them (OR: 1.83; 95% CI: 1.73–1.93; p < 0.001). Malnutrition and MR could be reduced by increasing economic level, supporting people living alone or being single, widowed, and divorced, and improving lifelong learning.

Absolute risk of tuberculosis among untreated populations with a positive tuberculin skin test or interferon-gamma release assay result: systematic review and meta-analysis

OBJECTIVE

To determine the annual rate of tuberculosis development after a positive tuberculin skin test (TST) or interferon-gamma release assay result (IGRA), or both, among untreated populations with characteristics believed to increase the risk of tuberculosis (at risk populations).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Embase, Medline, and Cochrane Controlled Register of Trials from 1 January 1990 to 17 May 2019, for studies in humans published in English or French. Reference lists were reviewed.

ELIGIBILITY CRITERIA AND DATA ANALYSIS

Retrospective or prospective cohorts and randomised trials that included at least 10 untreated participants who tested positive to tuberculosis antigens (contained in TST or IGRA, or both) followed for at least 12 months. Following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) and meta-analyses of observational studies in epidemiology (MOOSE) guidelines, two reviewers independently extracted study data and assessed quality using a modified quality assessment of diagnostic accuracy studies (QUADAS-2) tool. Data were pooled using random effects generalised linear mixed models.

MAIN OUTCOME MEASURES

The primary outcome was tuberculosis incidence per 1000 person years among untreated participants who tested positive (TST or IGRA, or both) in different at risk subgroups. Secondary outcomes were the cumulative incidence of tuberculosis and incidence rate ratios among participants with a positive test result for latent tuberculosis infection compared with those with a negative test result in at risk subgroups.

RESULTS

122 of 5166 identified studies were included. In three general population studies, the incidence of tuberculosis among 33 811 participants with a TST induration of ≥10 mm was 0.3 (95% confidence interval 0.1 to 1.1) per 1000 person years. Among 116 197 positive test results for latent tuberculosis infection in 19 different at risk populations, incidence rates were consistently higher than those in the general population. Among all types of tuberculosis contacts, the incidence of tuberculosis was 17.0 (95% confidence interval 12.9 to 22.4) per 1000 person years for participants with a positive IGRA result and 8.4 (5.6 to 12.6) per 1000 person years for participants with a positive TST result of ≥5 mm. Among people living with HIV, the incidence of tuberculosis was 16.9 (10.5 to 27.3) for participants with a positive IGRA result and 27.1 (15.0 to 49.0) for participants with a positive TST result of ≥5 mm. Rates were also high for immigrants, people with silicosis or requiring dialysis, transplant recipients, and prisoners. Incidence rate ratios among test positive versus test negative participants were significantly greater than 1.0 in almost all risk groups, for all tests.

CONCLUSIONS

The incidence of tuberculosis is substantial in numerous at risk populations after a positive TST or IGRA result. The information from this review should help inform clinical decisions to test and treat for latent tuberculosis infection.

STUDY REGISTRATION

PROSPERO CRD42019136608.

Maternal exposure to violence and offspring neurodevelopment: A systematic review

BACKGROUND

Stress during pregnancy is known to affect fetal neurodevelopment. It seems likely therefore that intimate partner violence (IPV) and domestic violence (DV) as extreme stressors will have a similarly adverse effect.

OBJECTIVES

A systematic review was conducted to assess the association between prenatal exposure to violence for mothers and developmental difficulties in their children.

DATA SOURCES

PubMed, PsycInfo, CINAHL, ERIC, Science Direct, SCOPUS, PsyARTICLES, Networked Digital Library of Theses and Dissertations, Women's Studies International and Gender Studies Database were all searched using the agreed search terms.

STUDY SELECTION AND DATA EXTRACTION

We include studies of women who have experienced any violence, fear of violence or aggression while pregnant, including emotional, psychological, physical or sexual violence in the context of IPV or DV. Studies were excluded if the neurodevelopmental outcomes of the offspring were not assessed. Studies from all countries were included, in English or translated to English, and search dates were not restricted. We included all years from inception of the database until the search date.

SYNTHESIS

Study design and biases, assessment tools, management of confounding, results and overall quality were assessed.

RESULTS

We identified 11 papers reporting on observational studies. Almost three quarters of the studies found a relationship between prenatal exposure to violence and developmental difficulties in the offspring. Differing assessment tools were used with a range of data collected and not all adjusted their findings for the same confounders.

CONCLUSIONS

Current evidence on the relationship between prenatal violence exposure, as IPV or DV, and consequent child developmental disorders remains limited. Future research using comprehensive study designs, larger samples and longitudinal follow-up of the offspring could clarify this association. While maternal trauma resulting from exposure to violence may play an important role in childhood development disorders, additional intervening factors on the pathway need further explored.

Integrated characterization and validation of the prognostic significance of microRNA-200s in colorectal cancer

Background

Accumulating evidence has demonstrated that microRNA-200s (miR-200a, miR-200b and miR-200c) could serve as promising molecular biomarkers for cancer prognosis. Nevertheless, the associations between miR-200s expression and colorectal cancer (CRC) prognosis remain controversial.

Methods

We applied two mainstream approaches combining meta-analysis and bioinformatics analysis to answer whether miR-200s were associated with the prognosis of CRC patients and why miR-200s could be used as prognostic biomarkers for CRC.

Results

Consequently, low expression of miR-200s was associated with unfavorable overall survival (OS) in CRC patients (HR: 1.09; 95% CI 1.01–1.17; P = 0.025). According to the subgroup analysis, the prognostic role of miR-200s was more significant for tissue samples, large samples, American patients and miR-200a subgroups. Then the target genes of miR-200s were predicted and applied for functional enrichment analyses. The results showed that the target genes of miR-200s were mainly enriched into some vital ontology subjects such as regulation ability, key cell structures and binding function. Moreover, a series of important signaling pathways were identified, which were significantly linked with the initiation and progression of CRC. Additionally, a protein‑protein interaction (PPI) network of miR-200s targets was constructed to screen hub genes and modules. The identified hub genes and modules were validated to be highly involved in the occurrence and development of CRC.

Conclusions

Current evidences revealed that miR-200s could be promising biomarkers for CRC prognosis. However, the findings still need to be validated with more larger-scale prospective studies and biological experiments before miR-200s could be applied into clinical application.

Internalizing Symptoms in Pediatric Migraine: A Systematic Review Protocol

OBJECTIVES

The primary objective of the proposed systematic review is to determine if there is an association between internalizing disorders and symptoms (ie, subclinical symptoms) and migraine in children and adolescents.

METHODS

We will perform a peer-reviewed Peer Review of Electronic Search Strategies search of MEDLINE, Embase, PsycINFO, and CINAHL from inception to December 2019. The authors will also review all reference lists of included studies for relevant citations. Observational studies on the association of pediatric migraine with internalizing disorders and symptoms will be included in this review. Case-control, cohort, and cross-sectional studies that include participants aged 18 years and under will be eligible for inclusion. The primary outcome for this systematic review will be migraine and the exposures of interest will include internalizing disorders (eg, major depressive disorder, dysthymia, generalized anxiety disorder, and post-traumatic stress disorder) and internalizing symptoms (depression symptoms, anxiety symptoms, obsessive compulsive symptoms, and post-traumatic stress symptoms). Two investigators will independently carry out an initial screen of abstracts, followed by a second screen of full-text manuscripts. Data extraction will be completed by 2 independent investigators. Study quality will be assessed using the Newcastle-Ottawa criteria for case-control and cohort studies and using a modified version of the Newcastle-Ottawa criteria for cross-sectional studies. A narrative synthesis of the data will be provided and, if possible, data will be quantitatively summarized using appropriate meta-analytic methods. Throughout the manuscript, the Preferred Reporting Items for Systematic Review and Meta-Analysis reporting standards will be followed.

RESULTS

The goal of this systematic review will be to provide a narrative, and if possible, quantitative summary on the association between pediatric migraine and internalizing disorders and symptoms.

CONCLUSIONS

The methods applied in this systematic review protocol can be used to inform the design of future systematic reviews of observational studies in headache medicine. The results of this systematic review will be used to inform the clinical community on the association between pediatric migraine and internalizing disorders and symptoms and may also be used to inform the design of future research studies in this area.

Intravascular Ultrasound Imaging-Guided Versus Coronary Angiography-Guided Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis

Background

Intravascular ultrasound (IVUS) guidance during percutaneous coronary intervention (PCI) offers tomographic images of the coronary vessels, allowing optimization of stent implantation at the time of PCI. However, the long‐term beneficial effect of IVUS over PCI guided by coronary angiography (CA) alone remains under question. We sought to investigate the outcomes of IVUS‐guided compared with CA‐guided PCI.

Methods and Results

We performed a comprehensive search of PubMed, Medline, and Cochrane Central Register, looking for randomized controlled trials and observational studies that compared PCI outcomes of IVUS with CA. Data were aggregated for the primary outcome measure using the random‐effects model as pooled risk ratio (RR). The primary outcomes were the rate of cardiovascular death, need for target lesion revascularization, occurrence of myocardial infarction, and rate of stent thrombosis. A total of 19 studies met the inclusion criteria, comprising 27 610 patients divided into IVUS (n=11 513) and CA (n=16 097). Compared with standard CA‐guided PCI, we found that the risks of cardiovascular death (RR, 0.63; 95% CI, 0.54–0.73), myocardial infarction (RR, 0.71; 95% CI, 0.58–0.86), target lesion revascularization (RR, 0.81; 95% CI, 0.70–0.94), and stent thrombosis (RR, 0.57; 95% CI, 0.41–0.79) were all significantly lower using IVUS guidance.

Conclusions

Compared with standard CA‐guided PCI, the use of IVUS imaging guidance to optimize stent implantation is associated with a reduced risk of cardiovascular death and major adverse events, such as myocardial infarction, target lesion revascularization, and stent thrombosis.

Inter-rater reliability and validity of risk of bias instrument for non-randomized studies of exposures: a study protocol

BACKGROUND

A new tool, "risk of bias (ROB) instrument for non-randomized studies of exposures (ROB-NRSE)," was recently developed. It is important to establish consistency in its application and interpretation across review teams. In addition, it is important to understand if specialized training and guidance will improve the reliability in the results of the assessments. Therefore, the objective of this cross-sectional study is to establish the inter-rater reliability (IRR), inter-consensus reliability (ICR), and concurrent validity of the new ROB-NRSE tool. Furthermore, as this is a relatively new tool, it is important to understand the barriers to using this tool (e.g., time to conduct assessments and reach consensus-evaluator burden).

METHODS

Reviewers from four participating centers will apprise the ROB of a sample of NRSE publications using ROB-NRSE tool in two stages. For IRR and ICR, two pairs of reviewers will assess the ROB for each NRSE publication. In the first stage, reviewers will assess the ROB without any formal guidance. In the second stage, reviewers will be provided customized training and guidance. At each stage, each pair of reviewers will resolve conflicts and arrive at a consensus. To calculate the IRR and ICR, we will use Gwet's AC₁ statistic. For concurrent validity, reviewers will appraise a sample of NRSE publications using both the Newcastle-Ottawa Scale (NOS) and ROB-NRSE tool. We will analyze the concordance between the two tools for similar domains and for the overall judgments using Kendall's tau coefficient. To measure evaluator burden, we will assess the time taken to apply ROB-NRSE tool (without and with guidance), and the NOS. To assess the impact of customized training and guidance on the evaluator burden, we will use the generalized linear models. We will use Microsoft Excel and SAS 9.4, to manage and analyze study data, respectively.

DISCUSSION

The quality of evidence from systematic reviews that include NRSE depends partly on the study-level ROB assessments. The findings of this study will contribute to an improved understanding of ROB-NRSE and how best to use it.

Impact of multi-drug resistant bacteria on economic and clinical outcomes of healthcare-associated infections in adults: Systematic review and meta-analysis

Background

Infections with multidrug resistant (MDR) bacteria in hospital settings have substantial implications in terms of clinical and economic outcomes. However, due to clinical and methodological heterogeneity, estimates about the attributable economic and clinical effects of healthcare-associated infections (HAI) due to MDR microorganisms (MDR HAI) remain unclear. The objective was to review and synthesize the evidence on the impact of MDR HAI in adults on hospital costs, length of stay, and mortality at discharge.

Methods and findings

Literature searches were conducted in PubMed/MEDLINE, and Google Scholar databases to select studies that evaluated the impact of MDR HAI on economic and clinical outcomes. Eligible studies were conducted in adults, in order to ensure homogeneity of populations, used propensity score matched cohorts or included explicit confounding control, and had confirmed antibiotic susceptibility testing. Risk of bias was evaluated, and effects were measured with ratios of means (ROM) for cost and length of stay, and risk ratios (RR) for mortality. A systematic search was performed on 14^th March 2019, re-run on the 10^th of June 2019 and extended the 3^rd of September 2019. Small effect sizes were assessed by examination of funnel plots. Sixteen articles (6,122 patients with MDR HAI and 8,326 patients with non-MDR HAI) were included in the systematic review of which 12 articles assessed cost, 19 articles length of stay, and 14 mortality. Compared to susceptible infections, MDR HAI were associated with increased cost (ROM 1.33, 95%CI [1.15; 1.54]), prolonged length of stay (ROM 1.27, 95%CI [1.18; 1.37]), and excess in-hospital mortality (RR 1.61, 95%CI [1.36; 1.90]) in the random effects models. Risk of publication bias was only found to be significant for mortality, and overall study quality good.

Conclusions

MDR HAI appears to be strongly associated with increases in direct cost, prolonged length of stay and increased mortality. However, further comprehensive studies in this setting are warranted.

Trial registration

PROSPERO (CRD42019126288).

Indicators Associated With Job Morale Among Physicians and Dentists in Low-Income and Middle-Income Countries: A Systematic Review and Meta-analysis

IMPORTANCE

Improving health care in low- and middle-income countries (LMICs) requires a workforce with positive job morale. However, the level of job morale in this population remains unclear.

OBJECTIVE

To analyze studies measuring the job morale of physicians and dentists working in LMICs, using levels of job burnout, job satisfaction, and job motivation as indicators of job morale.

DATA SOURCES

A comprehensive search of Scopus, PubMed, PsycINFO, EMBASE, Web of Science, and the Cochrane Library, from database inception to October 30, 2018, and gray literature was performed.

STUDY SELECTION

Studies were eligible if at least 50% of the sample were qualified physicians and/or dentists working in public health care settings in LMICs. Three indicators of job morale in this population were used: job burnout, job satisfaction, and job motivation. Of 12 324 records reviewed, 79 studies were included in the systematic review and 59 were eligible for the meta-analysis.

DATA EXTRACTION AND SYNTHESIS

Data were extracted independently by several investigators in accordance with the Meta-analyses of Observational Studies in Epidemiology (MOOSE) reporting guidelines. Random-effects meta-analyses, planned subgroup analyses, and metaregression were performed. The Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies was used to assess bias.

MAIN OUTCOMES AND MEASURES

Levels of job burnout, job satisfaction, and job motivation as indicators of job morale.

RESULTS

Overall, 12 324 records were identified. Of them, 80 records, representing 79 studies and involving 45 714 participants across 37 LMICs, met the inclusion criteria for the review; however, only 3 were from low-income countries. In 21 studies with 9092 participants working mainly in middle-income countries, 32% (95% CI, 27%-38%; I2 = 95.32%; P < .001) reported job burnout, and in 20 studies with 14 113 participants, 60% (95% CI, 53%-67%; I2 = 98.21%; P < .001) were satisfied with their job overall. Sufficient data were not available for a meta-analysis of job motivation.

CONCLUSIONS AND RELEVANCE

The findings suggest that, among physicians and dentists working mainly in middle-income countries, more than half reported having positive job morale. Positive job morale among physicians and dentists may help with recruitment and retention and thus support programs for improving health care in LMICs.

Structuring Mentoring in Medicine and Surgery. A Systematic Scoping Review of Mentoring Programs Between 2000 and 2019

INTRODUCTION

Evidence of novice mentoring's successes in having senior clinicians support junior doctors and/or medical students in their clinical, academic, and research goals has spurred efforts to include mentoring in the core medical curriculum. However, lack of effective structuring threatens the viability of mentoring programs, precipitating ethical concerns about mentoring. This review aims to answer the question "what is known about mentoring structures in novice mentoring among medical students and junior doctors in medicine and surgery postings?," which will guide the design of a consistent structure to novice mentoring.

METHODS

Levac (2010)'s framework was used to guide this systematic scoping review of mentoring programs in medicine and surgery published between 1 January 2000 and 31 December 2019 in PubMed, ScienceDirect, ERIC, Embase, Scopus, Mednar, and OpenGrey. A "split approach" involving concurrent independent use of a directed content analysis and thematic approach was used to analyze included articles.

RESULTS

Three thousand three hundred ninety-five abstracts were identified. There was concordance between the 3 themes and categories identified in analyzing the 71 included articles. These were the host organization, mentoring stages, and evaluations.

CONCLUSION

The data reveal the need for balance between ensuring consistency and flexibility to meet the individual needs of stakeholders throughout the stages of the mentoring process. The Generic Mentoring Framework provides a structured approach to "balancing" flexibility and consistency in mentoring processes. The Generic Mentoring Framework is reliant upon appropriate, holistic, and longitudinal assessments of the mentoring process to guide adaptations to mentoring processes and ensure effective support and oversight of the program.

Determinants of birth asphyxia among newborns in Ethiopia: A systematic review and meta-analysis

OBJECTIVE

The aim of this systematic review and meta-analysis was to estimate the pooled magnitude of birth asphyxia and its determinants in Ethiopia.

METHODS

The databases, including PubMed, Medline, CINAHL, EMBASE, and other relevant sources, were used to search relevant articles. Both published and unpublished studies, written in English and carried out in Ethiopia, were included in the study. Quality of evidence was assessed by the relevant of the Joanna Briggs Institute tool. RevMan v5.3 statistical software was used to undertake the meta-analysis using a Mantel-Haenszel random-effects model. Heterogeneity was evaluated using the Cochran Q test, and I2 statistics was considered to assess its level. The outcome was measured using a 95% confidence interval (CI).

RESULTS

The pooled prevalence of birth asphyxia was 22.8% (95% CI: 13-36.8%]. Illiterate mothers (adjusted odds ratio [AOR]; 1.96, 95% CI: 1.44-2.67), antepartum hemorrhage (APH) (AOR; 3.43, 95% CI: 1.74-6.77), cesarean section (AOR; 3.66, 95% CI: 1.35-9.91), instrumental delivery (AOR; 2.74, 95% CI: 1.48-5.08), duration of labor (AOR; 3.09, 95% CI: 1.60-5.99), pregnancy induced hypertension (AOR; 4.35, 95% CI: 2.98-6.36), induction of labor (AOR; 3.69, 95% CI: 2.26-6.01), parity (AOR; 1.29, 95% CI: 1.03-1.62), low birth weight (LBW) (AOR; 5.17, 95% CI: 2.62-10.22), preterm (AOR; 3.98, 95% CI: 3.00-5.29), non-cephalic presentation (AOR; 4.33, 95% CI: 1.97-9.51), and meconium staining (AOR; 4.59, 95% CI: 1.40-15.08) were significantly associated with birth asphyxia.

CONCLUSION

The magnitude of birth asphyxia was very high. Maternal education, APH, mode of delivery, prolonged labor, induction, LBW, preterm, meconium-staining, and non-cephalic presentation were determinants of birth asphyxia. Hence, to reduce birth asphyxia and associated neonatal mortality, attention should be directed to improve the quality of intrapartum service and timely communication between the delivery team. In addition, intervention strategies aimed at reducing birth asphyxia should target the identified determinants.

Endoscopic resection for non-polypoid dysplasia in inflammatory bowel disease: a systematic review protocol

INTRODUCTION

Non-polypoid low-grade dysplasia in inflammatory bowel disease is associated with a medium increased risk of colorectal cancer, while treatment recommendations remain controversial. We aim to evaluate the efficacy and safety of endoscopic treatment for non-polypoid dysplasia in patients with inflammatory bowel disease.

METHODS AND ANALYSIS

Medline, Embase, Cochrane Library, Scopus, Web of Science and clinical trials registry from database inception to the search date will be used to retrieve eligible studies. Studies that report the curative resection rate or any of other secondary outcomes of endoscopic treatment in patients with non-polypoid dysplasia in inflammatory bowel disease will be included in the analysis. We will conduct quantitative synthesis if the eligible studies are homogeneous judging from clinical and methodological perspectives.

ETHICS AND DISSEMINATION

Ethical approval for this study was waived by the Ethics Committee of Peking Union Medical College Hospital because there are no individual data involved in the analysis and all the combined results will be retrieved from study-level data. We plan to disseminate results through peer-reviewed journals or conference abstracts.

PROSPERO REGISTRATION NUMBER

CRD42019120413.

Prevalence of common mental health disorders in adults who are high or costly users of healthcare services: protocol for a systematic review and meta-analysis

INTRODUCTION

In all healthcare settings, a small proportion of patients account for a large level of healthcare use and associated high healthcare costs. Depression and anxiety are common co-morbidities in patients who are high users of care. The aims of this systematic review are to: (1) estimate the prevalence of anxiety/depression in adults who are high users of general physical healthcare services and/or who accrue high healthcare costs (2) estimate the magnitude of healthcare use associated with the presence of anxiety/depression.

METHODS AND ANALYSIS

This review will include any studies where patients are high users of primary, secondary or emergency healthcare services and/or accrue high healthcare costs. This is the first systematic review to focus on patients who are over the age of 18, whose degree of anxiety/depression has been evaluated with a standardised questionnaire or by a clinical interview generating a diagnosis according to international diagnostic criteria. The review will include eligible studies indexed in Medline, PsychINFO, Embase, Cumulative Index to Nursing and Allied Health Literature, Prospective Register of Systematic Reviews, Cochrane Library from inception to 1 April 2019. We will estimate the prevalence of anxiety/depression in these populations and the magnitude of use associated with anxiety/depression across various general physical healthcare settings. We will provide a narrative description of findings and factors that may influence them. A meta-analysis may be pursued if the degree of heterogeneity across studies is acceptable.

ETHICS AND DISSEMINATION

This systematic review will use data from existing studies, hence no ethical approvals are required. Findings will be disseminated in a peer-reviewed publication and at relevant academic meetings.

PROSPERO REGISTRATION NUMBER

PROSPERO CRD42018102628.

Estimating morbidity due to stroke in Nigeria: a systematic review and meta-analysis

BACKGROUND

The response to stroke in Nigeria is impaired by inadequate epidemiologic information. We sought to collate available evidence and estimate the incidence of stroke and prevalence of stroke survivors in Nigeria.

METHODS

Using random effects meta-analysis, we pooled nationwide and regional incidence and prevalence of stroke from the estimates reported in each study.

RESULTS

Eleven studies met our selection criteria. The pooled crude incidence of stroke in Nigeria was 26.0 (12.8-39.0) /100,000 person-years, with this higher among men at 34.1 (9.7-58.4) /100,000, compared to women at 21.2 (7.4-35.0) /100,000. The pooled crude prevalence of stroke survivors in Nigeria was 6.7 (5.8-7.7) /1000 population, with this also higher among men at 6.4 (5.1-7.6) /1000, compared to women at 4.4 (3.4-5.5) /1000. In the period 2000-2009, the incidence of stroke in Nigeria was 24.3 (95% CI: 11.9-36.8) per 100,000, with this increasing to 27.4 (95% CI: 2.2-52.7) per 100,000 from 2010 upwards. The prevalence of stroke survivors increased minimally from 6.0 (95% CI: 4.6-7.5) per 1000 to 7.5 (95% CI: 5.8-9.1) per 1000 over the same period. The prevalence of stroke survivors was highest in the South-south region at 13.4 (9.1-17.8) /100,000 and among rural dwellers at 10.8 (7.5-14.1) /100,000.

CONCLUSION

Although study period does not appear to contribute substantially to variations in stroke morbidity in Nigeria, an increasing number of new cases compared to survivors may be due in part to limited door-door surveys, or possibly reflects an increasing mortality from stroke in the country.

Association between anxiety, depression and quality of life: study protocol for a systematic review of evidence from longitudinal studies

INTRODUCTION

Evidence from individual longitudinal studies suggests that anxiety and depression may impact quality of life. However, systematic reviews synthesising current evidence have mainly focused on specific samples. Thus, the aim of this study is to synthesise evidence from longitudinal studies on the association between anxiety, depression and quality of life in a systematic review.

METHODS AND ANALYSIS

A systematic review of evidence from longitudinal studies analysing the association between anxiety, depression and quality of life will be conducted, taking into account the current Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Several electronic databases from relevant fields of research (PubMed, PsycINFO, PSYNDEX, EconLit, NHS EED) will be searched in September 2018 using defined search terms, with an updated search planned. Moreover, reference lists of included studies will be searched manually. Study eligibility will be appraised in a two-step process against pre-defined inclusion/exclusion criteria. Primarily, information on study design and assessment, statistical methods, participant characteristics as well as results regarding our research question will be extracted. The quality of included studies will be assessed using an appropriate tool. Study selection, data extraction and assessment of study quality will be performed by two reviewers. Disagreements will be resolved through discussion or by inclusion of a third party. Results will be synthesised narratively in text and tables. Depending on the number and heterogeneity of the studies included, a meta-analysis will be performed.

ETHICS AND DISSEMINATION

As no primary data will be collected, approval from an ethics committee is not required. Results will be disseminated through conference presentations and publication in a peer-reviewed, scientific journal.

PROSPERO REGISTRATION NUMBER

CRD42018108008.

Prevalence of common mental disorders in widowhood: A systematic review and meta-analysis

BACKGROUND

Widowed people have a high risk of common mental disorders, however no summary estimates of the prevalences exist. The aim of this study was to conduct a systematic review and meta-analysis of the prevalence of common mental disorders in widowed people in the community.

METHODS

MEDLINE, Embase and PsycInfo were searched for papers reporting on prevalence of common mental disorders and widowhood. Eligible studies were included in random effects meta-analyses of the prevalence of depression and anxiety disorders. Subgroup analyses were performed on method of assessment of depression and age and sex.

RESULTS

The literature search identified 13,781 titles of which 42 were eligible for meta-analysis. The pooled prevalence of depression in studies using a screening scale was 40.6% (33.6%-47.6%) (n = 30). For studies using full diagnostic criteria the pooled prevalence of depression was 19.2% (13.4%-25.0%) (n = 12). Subgroup analyses of age (≥ or < 65) and sex did not show any differences regarding depression. Five studies reported the prevalence of anxiety disorders. The pooled prevalence estimate was 26.9% (8.1%-45.7%).

LIMITATIONS

The prevalence estimates in this study are summary estimates of prevalences from existing literature. Although the reporting bias assessment showed no evidence, there could be some reporting bias, as studies might only present results if there is a high prevalence.

CONCLUSIONS

Widowed people have a high prevalence of depression and anxiety disorders. The high prevalence of depression was independent of age and sex. The study identifies a population group at high risk needing special attention in clinical practice.

COSMOS-E: Guidance on conducting systematic reviews and meta-analyses of observational studies of etiology

BACKGROUND

To our knowledge, no publication providing overarching guidance on the conduct of systematic reviews of observational studies of etiology exists.

METHODS AND FINDINGS

Conducting Systematic Reviews and Meta-Analyses of Observational Studies of Etiology (COSMOS-E) provides guidance on all steps in systematic reviews of observational studies of etiology, from shaping the research question, defining exposure and outcomes, to assessing the risk of bias and statistical analysis. The writing group included researchers experienced in meta-analyses and observational studies of etiology. Standard peer-review was performed. While the structure of systematic reviews of observational studies on etiology may be similar to that for systematic reviews of randomised controlled trials, there are specific tasks within each component that differ. Examples include assessment for confounding, selection bias, and information bias. In systematic reviews of observational studies of etiology, combining studies in meta-analysis may lead to more precise estimates, but such greater precision does not automatically remedy potential bias. Thorough exploration of sources of heterogeneity is key when assessing the validity of estimates and causality.

CONCLUSION

As many reviews of observational studies on etiology are being performed, this document may provide researchers with guidance on how to conduct and analyse such reviews.

Relation between health literacy, self-care and adherence to treatment with oral anticoagulants in adults: a narrative systematic review

BACKGROUND

Oral anticoagulants (OAC) are widely used in patients with cardiovascular diseases. However, for optimal OAC self-care patients must have skills, among which health literacy (HL) is highlighted. We aimed to describe the relation between HL and self-care in cardiovascular patients on OAC treatment.

METHODS

Electronic searches were carried out in the PubMed, Scopus, Embase, CINAHL, Web of Science, Cochrane Library, SciELO, IME-Biomedicina, CUIDEN Plus and LILACS databases, limited to Spanish and English language and between January 2000-December 2016. Papers reported on adults older than 18 years, taking OAC by themselves for at least three months. PRISMA guidelines were used for paper selection.

RESULTS

We identified 142 articles and finally included 10; almost all of them about warfarin. Our results suggest that in patients taking OAC treatments there is a positive relationship between HL and the level of knowledge. In addition, a small percentage of participants on the selected papers recognized the side effects and complications associated with OAC treatment. Lower HL level was associated with greater knowledge deficits and less adherence to treatment.

CONCLUSION

There is a paucity of research evaluating the effect of HL on diverse aspects of OAC treatments. There is a need to expand the evidence base regarding appropriate HL screening tools, determinants of adequate knowledge and optimal behaviours related to OAC self-management.

Meta-analysis: Key features, potentials and misunderstandings

A meta-analysis consists of a systematic approach to combine different studies in one design. Preferably, a protocol is written and published spelling out the research question, eligibility criteria, risk of bias assessment, and statistical approach. Included studies are likely to display some diversity regarding populations, calendar period, or treatment settings. Such diversity should be considered when deciding whether to combine (some) studies in a formal meta-analysis. Statistically, the fixed effect model assumes that all studies estimate the same underlying true effect. This assumption is relaxed in a random effects model and given the expected study diversity a random effects approach will often be more realistic. In the absence of statistical heterogeneity, fixed and random effects models give identical estimates. Meta-analyses are especially useful to provide a broader scope of the literature; they should carefully explore sources of between study heterogeneity and may show a treatment effect or an exposure-outcome association where individual studies are not powered. However, its validity largely depends on the validity of included studies.