A difference-in-differences approach to estimate the effect of income-supplementation on food insecurity

The Universal Child Care Benefit (UCCB) is a 2006 Canadian federal policy of income supplementation that provides parents with $100 monthly in Canadian dollars for each child aged <6years. The study main objective was to estimate the causal effect of UCCB on self-reported food insecurity overall and in vulnerable subgroups.

The Canadian Community Health Survey (2001-2009) was used to conduct a difference-in-differences (DID) regression analysis for the effect of the UCCB on self-reported food insecurity. Respondents were ages ≥12 in families with at least one child aged <6years (UCCB-eligible, n=22,737) or a child aged 6-11 but no child <6years (control group, n=17,664).

Over the study period 16.3% of respondents experienced some level of food insecurity. Overall, UCCB reduced the proportion of respondents reporting food insecurity by 2.4% (95% CI: -4.0%, -0.9%). There was a significantly stronger impact on food insecurity for respondents from households with yearly income below the population median (-4.3%, 95% CI: -7.2%, -1.4%) and respondents from single parent families (-5.4%, 95% CI: -10.3%, -0.6%).

We found that a relatively small monthly income supplementation results in a significant reduction in food insecurity at the population level, with larger effects in vulnerable groups.