A Systematic Review of Methods for Estimating Productivity Losses due to Illness or Caregiving in Low- and Middle-Income Countries

Background: Productivity losses are often included in costing studies and economic evaluations to provide a comprehensive understanding of the economic burden of disease. Global guidance on estimating productivity losses is sparse, especially for low-and middle-income countries (LMICs) where informal and unpaid work remains dominant. This study aims to describe current practices for valuing productivity losses in LMICs. 

Methods: We performed a systematic review of studies published before April 2022 using three databases, including PubMed, Cochrane Library and Web of Science Core Collection. We included any costing or economic evaluation study conducted in a LMIC that provided methodological details on how the monetary value for productivity losses was estimated. Two reviewers independently screened articles for inclusion, extracted data and assessed the quality of the studies. 

Results: A total of 281 articles were included. While most studies did not specify the overall approach used to measure and value productivity losses (58%), the human capital approach was the most frequently used approach to measure productivity losses when this was clearly stated (39%). The most common methods to estimate a monetary value for productivity losses were market wages (51%), self-reported wages (28%) and macroeconomic measures (15%).

Conclusion: Reporting standards for productivity losses in LMIC settings have room for improvement. While market wages were the most frequently used method to estimate the monetary value of productivity losses, this relies on context-specific data availability. Until a consensus is reached on if, when and how to include productivity losses in costing and economic evaluation studies, future studies could include a sensitivity analysis to explore the impact of different methods for estimating the monetary value of productivity losses.