WHO Collaborating Centre for Global Women's Health, Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, UK.
WHO Collaborating Centre for Global Women's Health, Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, UK
BMJ Open. 2023 May 11;13(5):e065538. doi: 10.1136/bmjopen-2022-065538.
Low dietary calcium intake is a risk factor for pre-eclampsia, a major contributor to maternal and perinatal mortality and morbidity worldwide. Calcium supplementation can prevent pre-eclampsia in women with low dietary calcium. However, the optimal dose and timing of calcium supplementation are not known. We plan to undertake an individual participant data (IPD) meta-analysis of randomised trials to determine the effects of various calcium supplementation regimens in preventing pre-eclampsia and its complications and rank these by effectiveness. We also aim to evaluate the cost-effectiveness of calcium supplementation to prevent pre-eclampsia.
We will identify randomised trials on calcium supplementation before and during pregnancy by searching major electronic databases including Embase, CINAHL, MEDLINE, CENTRAL, PubMed, Scopus, AMED, LILACS, POPLINE, AIM, IMSEAR, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform, without language restrictions, from inception to February 2022. Primary researchers of the identified trials will be invited to join the International Calcium in Pregnancy Collaborative Network and share their IPD. We will check each study's IPD for consistency with the original authors before standardising and harmonising the data. We will perform a series of one-stage and two-stage IPD random-effect meta-analyses to obtain the summary intervention effects on pre-eclampsia with 95% CIs and summary treatment-covariate interactions (maternal risk status, dietary intake, timing of intervention, daily dose of calcium prescribed and total intake of calcium). Heterogeneity will be summarised using tau, I and 95% prediction intervals for effect in a new study. Sensitivity analysis to explore robustness of statistical and clinical assumptions will be carried out. Minor study effects (potential publication bias) will be investigated using funnel plots. A decision analytical model for use in low-income and middle-income countries will assess the cost-effectiveness of calcium supplementation to prevent pre-eclampsia.
No ethical approvals are required. We will store the data in a secure repository in an anonymised format. The results will be published in peer-reviewed journals.
CRD42021231276.
低膳食钙摄入是子痫前期的一个风险因素，子痫前期是全球孕产妇和围产儿死亡和发病的主要原因。钙补充剂可以预防低膳食钙的妇女发生子痫前期。然而，钙补充的最佳剂量和时间尚不清楚。我们计划进行一项个体参与者数据（IPD）的随机试验荟萃分析，以确定各种钙补充方案在预防子痫前期及其并发症方面的效果，并按效果进行排序。我们还旨在评估钙补充预防子痫前期的成本效益。
我们将通过搜索主要的电子数据库，包括 Embase、CINAHL、MEDLINE、CENTRAL、PubMed、Scopus、AMED、LILACS、POPLINE、AIM、IMSEAR、ClinicalTrials.gov 和世界卫生组织国际临床试验注册平台，在没有语言限制的情况下，从成立到 2022 年 2 月，确定妊娠前和妊娠期间的钙补充随机试验。将邀请已确定试验的主要研究人员加入国际妊娠钙合作网络并分享他们的 IPD。在对数据进行标准化和协调之前，我们将检查每个研究的 IPD 是否与原始作者一致。我们将进行一系列一阶段和两阶段的 IPD 随机效应荟萃分析，以获得子痫前期的汇总干预效果及其 95%置信区间和汇总治疗协变量交互作用（孕产妇风险状况、膳食摄入量、干预时间、规定的每日钙剂量和钙总摄入量）。使用 tau、I 和 95%预测区间对新研究中的效果进行异质性总结。将进行敏感性分析以探索统计和临床假设的稳健性。使用漏斗图探索潜在的发表偏倚。用于中低收入国家的决策分析模型将评估钙补充预防子痫前期的成本效益。
不需要伦理批准。我们将以匿名格式将数据存储在一个安全的存储库中。研究结果将发表在同行评议的期刊上。
PROSPERO 注册号：CRD42021231276。
