Real-Life Testing of the Prescription Opioid Misuse Index in French Primary Care

Analgesic opioid (AO) misuse by patients ranges from 0% to 50%. General practitioners are the first prescribers of AO. Our objective was to validate the Prescription Opioid Misuse Index (POMI) in primary care. We conducted a psychometric study in patients with chronic pain who had been taking AOs for at least 3 months and were followed in general practice. Patients responded to the POMI at inclusion and after 2 weeks. The reference used was the DSM-V. Sixty-nine GPs included 160 patients (87 women, 54.4%), mean age 56.4 ± 15.2 years. The total POMI score was 1.50 ± 1.27, and 73/160 (45.6.0%) had a score ≥ 2 (misuse threshold). Internal validity was measured with the Kuder–Richardson coefficient, which was 0.44. Correlations between each item and the total score ranged from 0.06 to 0.35. Test–retest reliability was determined from 145 patients: Lin’s concordance coefficient was 0.57 [0.46, 0.68]. Correlation with the DSM-V (Spearman’s coefficient) was 0.52. The POMI does not have sufficient psychometric properties to be recommended as a tool to identify the misuse of AOs in primary care. This study clearly showed that there is a need to create a monitoring tool specific to primary care.