Figure 1.

Schema for defining study groups

Participants in intervention group 1 were newly exposed to LPO when the age cutoff was changed from 7 to 5 years in 2012, those in intervention group 2 were newly exposed when the age cutoff was changed from 10 to 7 years in 2010, those in control group 1 were unexposed, and those in control group 2 were continuously exposed. The arrows indicate follow-up (ie, the period from the date of policy change to 1 year after the change), and the horizontal lines indicate exposure groups. LPO=Lone Parent Obligations. *Exposure status was based on age of youngest child at 1 year before the change in the age eligibility cutoff for LPO. †Baseline measures for these groups could not be found within Understanding Society, and so they were not included in the analysis.