The opioid risk tool (ORT) is a commonly employed measure of risk of aberrant drug related behaviors (ADRB) in patients with chronic pain prescribed opioid therapy. In this study the discriminant predictive validity of the ORT was evaluated in a unique cohort of patients with chronic nonmalignant pain (CNMP) on long-term opioid therapy (LTOT) that displayed no evidence of developing an opioid use disorder (OUD) and a sample of patients with CNMP that developed an OUD after commencing opioid therapy. Results revealed that the original ORT was able to discriminate between patients with and without OUDs (OR=1.624; CI 95%: 1.539-1.715, p< 0.001). A weighted ORT eliminating the gender specific history of preadolescent sexual abuse item revealed comparable results (OR= 1.648; CI 95%: 1.539-1.742, p< 0.001). A revised unweighted ORT (ORT-OUD) removing the history of preadolescent sexual abuse item was notably superior in predicting the development of OUD in patients with CNMP on LTOT (OR= 3.085; CI 95%: 2.725-3.493, p< 0.001) with high specificity (0.851; CI 95%: 0.811-0.885), sensitivity (0.854; 95% CI: 0,799-0.898), positive (0.757; CI 95%: 0.709-0.799) and negative (0.914; CI 95%: 0.885-0.937) predictive values. Perspective: The revised ORT (ORT-OUD) is the first tool developed on a unique cohort to predict the risk of developing an OUD in patients with CNMP receiving opioid therapy, as opposed to ADRB that can reflect a number of other issues. The ORT-OUD has clinical utility in providing clinicians a simple, validated method to rapidly screen for the risk of developing OUD in patients on or being considered for opioid therapy.