OBJECTIVES: To compare employment outcomes reported by a completed randomised controlled trial (IPS-AD: Individual Placement and Support - Alcohol and Drug Dependence) with those observed during the English national expansion of IPS services, and to identify factors associated with improved outcomes.

METHODS: This was a secondary comparative analysis of five employment outcomes - employment rate, time to employment attainment, job tenure (longest single appointment duration), total time employed and job sustainment defined as ≥13 consecutive weeks employment, in two cohorts: the IPS-AD study intervention arm (n = 843) and IPS expansion participants (n = 3,182).

RESULTS: Compared with the IPS-AD cohort, the expansion cohort showed a higher employment rate (52% versus 30%; p-value <0.001); faster employment attainment (143 versus 180 days; p-value <0.001); longer job tenure (254 versus 110 days; p-value <0.001); greater total time employed (300 versus 133 days; p-value <0.001); and higher job sustainment (76% versus 42%; p-value <0.001).

CONCLUSION: Expansion outcomes were consistently more favourable than those observed in the IPS-AD study. Factors that may have contributed to improved outcomes included implementation and delivery enhancements, broadened eligibility criteria, and favourable environmental and economic conditions.