Excess mortality during the COVID-19 pandemic in low-income and lower middle-income countries: protocol for a systematic review and meta-analysis

Introduction: The COVID-19 pandemic has been marked by a massive death toll. However, the overall effect of the pandemic, including potential unintended negative impacts of some control measures, on mortality remains poorly understood in low-income and lower middle-income countries (LLMICs). This review aims to summarise the available literature on excess mortality in LLMICs, focusing on the methods and data sources used in estimating excess mortality and the drivers of excess mortality.

Methods and analysis: We will review the available literature and report results in line with the Preferred Reporting Items for Systematic Review and Meta-Analysis. Searches will be conducted in PubMed, Embase, Web of Science, Cochrane Library, Google Scholar and Scopus. All published studies that report on the estimates of excess mortality in populations of LLMICs will be included. This will include those with a publication date from 2019 onwards and those with at least a 1-year non-COVID-19 period as the comparator in the estimation of excess mortality during the pandemic. There will be no language restrictions on the search. The meta-analysis will include studies with extractable data on excess mortality, methods, population size, and observed and expected deaths. We will use the Mantel-Haenszel method to estimate the pooled risk ratio with 95% CIs.

Ethics and dissemination: As there is no primary data collection, there is no requirement for ethical review. The results will be disseminated through peer-reviewed journal publication and conference presentations.

Prospero registration number: CRD42022378267.