Dharmarajan Sumedha, Bhide Prajkta, Kar Anita
Birth Defects Research Foundation, Pune 411020, India.
Department of Public Health, School of Health Sciences and Technology, Dr. Vishwanath Karad MIT World Peace University, Pune 411038, India.
J Public Health (Oxf). 2025 Feb 28;47(1):e38-e55. doi: 10.1093/pubmed/fdae299.
Data on the birth prevalence of congenital anomalies in low- and middle-income countries report wide variations in prevalence estimates. We conducted a scoping review to identify the sources of bias in studies reporting birth prevalence of congenital anomalies in World Health Organization South-East Asia region (SEAR) countries.
PubMed and Google Scholar databases were screened for relevant literature. Data on study characteristics and sources of bias was extracted. A narrative synthesis of the data is reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist. A checklist for reporting studies on birth prevalence of congenital anomalies (CD-Checklist) was developed.
The literature search retrieved 47 articles. Birth prevalence varied from 0.21% to 9.68%. Sampling bias was evident as studies were single hospital studies, lacked relevant description of sample, did not justify sample size or describe the process of sampling. Information bias was identified as studies did not mention classification system used, and failed to clearly distinguish between number of malformations and babies with malformations. Observer and reporting bias were noted.
Several sources of bias introduce variations in birth prevalence reports of congenital anomalies in SEAR countries. A checklist (CD-Checklist) has been suggested which can guide investigators to minimize the risk of bias in studies.
低收入和中等收入国家先天性异常出生患病率的数据显示，患病率估计值存在很大差异。我们进行了一项范围综述，以确定世界卫生组织东南亚区域（SEAR）国家报告先天性异常出生患病率的研究中的偏差来源。
在PubMed和谷歌学术数据库中筛选相关文献。提取有关研究特征和偏差来源的数据。使用系统评价和Meta分析扩展版的首选报告项目清单（PRISMA-ScR）对数据进行叙述性综合分析。制定了一份报告先天性异常出生患病率研究的清单（CD清单）。
文献检索共获得47篇文章。出生患病率从0.21%到9.68%不等。抽样偏差很明显，因为研究多为单中心医院研究，缺乏对样本的相关描述，没有说明样本量的合理性或描述抽样过程。信息偏差表现为研究未提及所使用的分类系统，也未能明确区分畸形数量和患有畸形的婴儿数量。存在观察者偏差和报告偏差。
多种偏差来源导致了SEAR国家先天性异常出生患病率报告的差异。建议使用一份清单（CD清单），以指导研究人员尽量降低研究中的偏差风险。
