Patients being treated successfully with a drug of abuse and at low risk for abusing the drug nevertheless may be at high risk of being misidentified as a high risk of abuse. These patients may need and benefit from treatment with the drug but restricted or cut off from the treatment altogether due to the misidentification and then abandoned. Evaluating a patient's risk of drug treatment change due to a category misidentification may include developing a model for identifying such abandoned patients, applying the model to data of a patient, and determining a patient risk score for the patient based on a result of applying the model.