In-work tax credits for families and their impact on health status in adults

Lay Summary
Employment-conditional tax credits for families and their impact on health status in adults For low- and middle-income families, in-work tax credit for families (IWTC) interventions to reduce poverty and unemployment (both of which are thought to harm health) could be expected to improve health status in adults.

This review sought to assess the effects of IWTCs on health outcomes in working-age adults (18 to 64 years). The review included randomised and quasi-randomised controlled trials and cohort, controlled before-and-after and interrupted time series studies of IWTCs in working-age adults. We looked for studies which reported adult self rated general health; mental health/psychological distress; mental illness; overweight/obesity; alcohol use and tobacco use.

Five studies comprising a total of 5,677,383 participants (all women) were included in the review. These studies were all based in the US. Because all of these non-experimental studies had considerable systematic errors in the way they conducted their analysis, we judged this body of evidence to have very low overall quality.

This review found weak evidence that in-work tax credit for families interventions had no effect on health status, except for mixed evidence for tobacco use in adult women, where some studies suggested that rates of smoking reduced.