A Rasch analysis of the Current Opioid Misuse Measure for patients with chronic pain

Objective: Pilot study to assess psychometric indices of the Current Opioid Misuse Measure (COMM). Design: Correlational. Setting: Patients with varied chronic pain from a family healthcare center. Patients: Inclusion criteria were over 21 years of age and prescribed opioids for any-origin noncancer pain; 46 patients were enrolled. Outcome measure(s): The COMM, the Pain Self-Efficacy Questionnaire (PSE-Q), and the Patient Health Questionnaire-9 (PHQ-9) and a demographic questionnaire. Results: Preliminary analysis indicated issues with dimensionality and scale use. Analysis after remedial procedures yielded unidimensionality and appropriate scale use, with the measure showing invariance across sex and low significant correlation with the PHQ-9 but not the PSE-Q. Conclusions: The COMM had adequate reliability, measured a distinct construct, and no significant differential item function was found. However, scale use for this sample was questionable, and three items misfit the Rasch model. Replication with a larger sample is needed to ensure the measure's psychometric quality for diagnostic use.