Measurement of opioid misuse in the general Mexican population: Encodat 2025.

Abstract

Objective: To examine the prevalence of categorical self-reported opioid misuse and compare it to a post hoc corrected indicator in the general Mexican population.

Materials and methods: We used data from the 2025 Encuesta Nacional de Consumo de Drogas, Alcohol y Tabaco. We constructed indicators from self-reported categorical heroin/fentanyl use, prescription opioids misuse and opioid misuse and post hoc corrected versions based on the review of open-ended follow up questions by two experts. We estimated the prevalence from categorical self-report responses and compared it with the post hoc corrected indicators.

Results: The prevalence of self-reported prescription opioid misuse was 1 948.3 per 100 000 people, which decreased to 1 242.4 after correction. Self-reported heroin or fentanyl use was 370.7 per 100 000 people, with a corrected prevalence of 326.2. Self-reported opioid misuse had a prevalence of 2 229.6 per 100 000 people, which decreased to 1 482.3 after correction.

Conclusion: Misclassification was more frequent for prescription opioid misuse than for illicit opioid use. Simple categorical questions performed well for measuring illicit opioid use, but they moderately overestimated prescription and overall opioid misuse.