BACKGROUND:
Social health insurance, such as the Lagos State Health Insurance Scheme, subsidises healthcare services through a social risk pool (1). Health insurance is underutilised in Nigeria, despite the availability of various types (2, 3). Although the Lagos State government enacted the Lagos State Health Scheme (LSHS) law in 2015, (1, 4) several million Lagosians remain unenrolled, (5) leaving a significant health-financial risk. The objective of this study was to examine the predisposing, reinforcing, and enabling factors (6) associated with the utilisation of the LSHS.

METHODS:
This study employed a sequential mixed-methods design that combined qualitative and quantitative approaches, using multistage sampling. Data for the quantitative component were collected using a structured questionnaire, and for the qualitative component, using Key Informant Interviews (KIIs) and Focused Group Discussions (FGDs). Quantitative data were analysed using IBM SPSS Statistics version 21, and hypotheses were tested using correlation and regression analyses, with the significance level set at p < 0.05. The KIIs' and FGDs' data were thematically analysed.

RESULTS:
Female respondents accounted for 72.1%; the largest age group was 26–35 years (37%); and 40.6% were in business. The qualitative data showed 6% awareness, and the cost of premium, availability of drugs, and registration points, proximity to the PHC, and household size affect utilization. The utilisation rate of the LSHS was 37%. There was a strong association between gender, income, occupation, household size, and enabling factors (β = 0.182, t = 3.511, p = .001) and the utilisation of the LSHS. The combination of Enabling, Predisposing, and Reinforcing factors accounted for 4.2% (R2 = 0.042) of the variation in utilisation of the LSHS, a possible limitation.

CONCLUSIONS:
Factors like gender, occupation, income, household size, nearness to PHC, availability of drugs at the PHCs, cost and ease of registration affect the utilisation of the LSHS.