Effect of income on mental health and health behaviours, instrumental variables secondary analyses
| Outcome | Model 1: single | Model 2: married | Model 3: income-restricted | Model 4: federal EITC |
| Psychological distress | −0.098** (−0.15 to –0.047) | 0.16 (−0.27 to 0.59) | −0.049 (−0.098 to 0.0013) | −0.13** (−0.20 to –0.049) |
| Very good/excellent health | 0.0046 (−0.0032 to 0.012) | 0.0046 (−0.0032 to 0.012) | −0.00036 (−0.0045 to 0.0038) | −0.0013 (−0.021 to 0.018) |
| Currently drink alcohol | 0.0026 (−0.0023 to 0.0075) | −0.0067 (−0.022 to 0.0089) | 0.0035 (−0.00032 to 0.0074) | 0.012 (−0.0019 to 0.026) |
| Drink 3+ drinks per day | −0.0039 (−0.0079 to 0.000061) | −0.0028 (−0.015 to 0.0091) | −0.0023 (−0.0056 to 0.0009) | −0.0075 (−0.019 to 0.0038) |
| Currently smoke | 0.00024 (−0.0031 to 0.0036) | −0.0019 (−0.0097 to 0.0060) | 0.00078 (−0.0019 to 0.0035) | 0.0049 (−0.0062 to 0.016) |
| Cigarettes per day | −0.017 (−0.070 to 0.036) | −0.054 (−0.22 to 0.11) | −0.0053 (−0.054 to 0.044) | 0.010 (−0.18 to 0.20) |
Study sample was drawn from the Panel Study of Income Dynamics for survey years 1985–2015.
Model 1 is an IV model and restricts the analysis to single heads of household.
Model 2 is an IV model and restricts the analysis to married heads of household.
Model 3 is an IV model and restricts the analysis to households with income above US$0 and below US$100 000.
Model 4 is an IV model and uses only federal EITC as the instrumental variable.
All models adjusted for age and age-squared, education, marital status, number of children, household inflation-adjusted pre-tax earned income and income-squared, year fixed effects, and individual fixed effects. Robust SEs were clustered at the individual level.
*p<0.05; **p<0.01.
EITC, earned income tax credit; IV, instrumental variable.