The impact of income-support interventions on life course risk factors and health outcomes during childhood: a systematic review in high income countries

Abstract

AbstractIn high income countries one in five children still lives in poverty. This is known to adversely shape the life course health trajectory of these children; however, much less is understood on whether social and fiscal policies have the capacity to reverse this damage, which intervention is likely to be most effective and when these interventions should be delivered to maximise their impact. This systematic review attempts to address these questions by looking at the impact of income-support interventions delivered during the first 1,000 days of life on cardiovascular, metabolic, respiratory and mental health outcomes. The review was restricted to experimental or quasi experimental studies conducted in high income countries. Studies of interest were retrieved from multidisciplinary database as well as health, economic, social sciences-specific literature browsers. Evidence of interest were summarised via narrative synthesis approach. Robustness of findings was assessed by tabulating impact by health outcome, type of intervention and study design. Overall, 18 relevant papers were identified, including 16 independent studies, one meta-analysis of randomized control trials (RCTs) and one pooled analysis of RCTs. Income-support interventions included: unconditional/conditional cash transfers, income tax credit, welfare to work, and minimum wage salary policies. Most studies were conducted in North America. Overall, the evidence suggested a positive, albeit small, effect of most policies on birth weight outcomes, but limited effect on mental health indicators. Results seemed to be robust to the type of intervention, but not to the study design, with RCTs consistently less likely to detect an impact. Given the large number of people targeted by these programs, one could infer that – despite small – the observed effect may be still relevant at population level. Nonetheless, the limited generalisability of the evidence gathered hampers firm conclusions. For the future, the breath and scope of this literature need to be broadened to fully exploit the potential of these interventions and understand how their public health impact can be maximised.