Determination of a clinically important difference and definition of a responder threshold for the UCSD performance-based skills assessment (UPSA) in patients with major depressive disorder.

•UPSA was developed for schizophrenia patients and can predict real-world functioning.•We evaluated the psychometric properties of the UPSA in patients with MDD.•We also used two methods to determine a CID and CIR threshold for this population.•Construct validity was established in patients with moderate-to-severe MDD.•The CID and CIR methods support an UPSA increase of 6–7 points as meaningful.