Transcultural validation of a French–European version of the Prescription Opioid Misuse Index Scale (POMI-5F)

Purpose The Prescription Opioid Misuse Index scale (POMI) is a brief questionnaire used to assess opioid prescription misuse. In view of the increase in the prescription of opioid analgesics for chronic noncancer pain (CNCP), this tool is particularly useful during medical consultations to screen opioid misuse in patients using opioids. We sought to generate and validate a French–European translation of the POMI. Methods We conducted an observational, longitudinal, and multicenter psychometric study with crosscultural validation. All adult CNCP patients who were treated with opioids for at least three months, were followed in pain clinics, and spoke French were eligible. From September 2015 to November 2017, we included 163 patients and analyzed 154. We performed a pretest on a sample of representative patients to evaluate acceptability and understanding of translation. Study patients completed the POMI scale at a pain clinic (test phase), and we assessed test–retest reliability after two to four weeks by a second completion of the POMI scale at home by patients (retest phase). We subsequently explored psychometric properties of the POMI (acceptability, internal consistency, reproducibility, and external validity). Results Due to poor internal consistency and reproducibility, items 4, 7, and 8 of the original POMI scale were removed, and we proposed a five-question French–European version (POMI-5F). The internal consistency of POMI-5F was good (Cronbach’s α = 0.71), as was test–retest reliability (r = 0.65 [0.55–0.67]). The external validity of POMI-5F, compared with the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, was moderate but significant (r = 0.45; P < 0.001). The optimal POMI-5F cut-off score to indicate misuse was 2/5 (sensitivity = 0.95 and specificity = 0.54). Conclusion We generated and validated a French–European translation of the POMI scale, POMI-5F, for use by French researchers and physicians to identify opioid misuse in CNCP patients.