Systematic review and meta-analysis of global birth prevalence of clubfoot: a study protocol

INTRODUCTION Clubfoot is a common congenital birth defect, with an average prevalence of approximately 1 per 1000 live births, although this rate is reported to vary among different countries around the world. If it remains untreated, clubfoot causes permanent disability, limits educational and employment opportunities, and personal growth. The aim of this systematic review and meta-analysis is to estimate the global birth prevalence of congenital clubfoot. METHODS AND ANALYSIS Electronic databases including MEDLINE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, Global Health, Latin American & Caribben Health Science Literature (LILACS), Maternity and Infant Care, Web of Science, Scopus and Google Scholar will be searched for observational studies based on predefined criteria and only in English language from inception of database in 1946 to 10 November 2017. A standard data extraction form will be used to extract relevant information from included studies. The Joanna Briggs Institute appraisal checklist will be used to assess the overall quality of studies reporting prevalence. All included studies will be assessed for risk of bias using a tool developed specifically for prevalence studies. Forest plots will be created to understand the overall random effects of pooled estimates with 95% CIs. An I2 test will be done for heterogeneity of the results (P>0.05), and to identify the source of heterogeneity across studies, subgroup or meta-regression will be used to assess the contribution of each variable to the overall heterogeneity. A funnel plot will be used to identify reporting bias, and sensitivity analysis will be used to assess the impact of methodological quality, study design, sample size and the impact of missing data. ETHICS AND DISSEMINATION This review will be conducted completely based on published data, so approval from an ethics committee or written consent will not be required. The results will be disseminated through a peer-reviewed publication and relevant conference presentations. PROSPERO REGISTRATION NUMBER CRD42016041922.