Health impacts of UK Lone Parent Obligations: a natural experiment study using data from the UK household panel survey, Understanding Society

In the UK, lone mothers receiving income support are required to seek work as a condition of receiving that support once their youngest child reaches a specified age. Since 2008, the lower age limit at which these so-called Lone Parent Obligations (LPO) apply has been reduced in steps. We aimed to assess the health impact of exposing increasing numbers of lone parents to welfare conditionality. We carried out a natural experimental study in the UK using data from Understanding Society, a UK household longitudinal panel study (2009–13). The primary outcome was the mental health component of SF-12. The physical health component of SF-12 and self-rated health were secondary outcomes. Lone mothers newly exposed to LPO when the age limit was reduced to 7 years old and then to 5 (two intervention groups) were compared with lone mothers who remained unexposed (control 1) or who were exposed before the change (control 2). A difference-in-difference linear regression analysis was conducted on an intention-to-treat basis, adjusting for maternal age, education, and number of children. The total sample size was 2359, 291 in the intervention groups (146 age 7 years, 145 age 5 years) and 1966 in the control groups (711 control 1, 1357 control 2). Mental health of lone mothers declined in intervention groups compared with control groups. The mental health component score for lone mothers newly exposed to LPO with children aged 4–6 years changed by −1·39 (95% CI −4·08 to 1·29) compared with unexposed lone mothers and by −2·29 (−4·57 to 0·00) compared with previously exposed lone mothers. Data for the two intervention groups combined were, respectively, −2·13 (−4·17 to −0·10) and −2·21 (−4·13 to −0·30). No impact on SF-12 physical health component scores or on self-rated health was found. In the UK, welfare conditionality appears to have adversely impacted mental health of lone mothers. The study only investigated short-term effects, but the pattern of findings was consistent over the two age comparison groups. Welfare conditionality is increasingly common in high-income countries; possible adverse impacts should be considered rather than assuming that all impacts will be positive. Further research should ascertain longer-term effects of exposure to LPO and the effects of the further reduction in the age threshold from 5 to 3 years in 2017. NHS Research Scotland senior clinical fellowship (SCAF/15/02), Medical Research Council (MC_UU_12017/13 & MC_UU_12017/15), Scottish Go