Willing everywhere but in health: a within-person national survey of artificial intelligence acceptance among 11 013 Nigerian adults

Introduction. Artificial intelligence is entering African primary care partly on the premise that populations underserved by clinicians will accept an algorithm in a clinician's place, a premise rarely tested where it matters. We measured how far Nigerian adults separate health from every other use of AI in their lives. Methods. Cross-sectional national survey of 11,013 adults across Nigeria's 36 states and Federal Capital Territory, July-October 2025. About 60% were recruited face to face, with translation where needed, so neither literacy nor English was required to take part. Each rated willingness to use AI in nine everyday situations on a 1-5 scale, one being health advice when no doctor was available. The primary outcome was a within-person difference: health minus the respondent's mean of the other eight. Associations were estimated by ordinary least squares with cluster-robust (CR2) standard errors by state. Results. Health finished last of the nine (mean 3.10), below promoting one's own political party (3.40). The within-person gap was -0.568 (95% CI -0.594 to -0.543; dz -0.417), widening to -0.904 among the 6,924 who distinguished between domains. Keeping a clinician in view did not relieve it: 22.9% would trust AI to help doctors diagnose against 25.5% who would use it to check their own symptoms. Among barriers respondents named, the gap was wider for language (beta -0.427, 95% CI -0.718 to -0.136) and unfriendly staff (-0.411, -0.616 to -0.207), narrower for missing equipment (+0.231, +0.040 to +0.423) and narrower among fluent English speakers (+0.386 per SD, +0.130 to +0.643). Conclusion. Nigerian adults accept AI across their lives and withhold it from their health, most firmly where care has been unaffordable, unintelligible or unkind. No configuration tested commanded majority willingness, including AI presented as assisting a clinician; willingness belongs alongside connectivity and data in deployment planning, not assumed.