Reliable change indexes for memory performance in schizophrenia as a means to determine drug-induced cognitive decline.

Some psychotropic medications frequently prescribed in schizophrenia, especially agents that contain anticholinergic properties, have adverse effects on learning and memory. Given the impact of memory on both functional and symptomatic outcome in schizophrenia, it is important to determine if patients suffer from medication-related memory impairment. This study provides a statistical methodology for identifying medication-related changes in memory functioning. Reliable change estimates were determined for Rey Auditory Verbal Learning Test performance in 38 inpatients with schizophrenia. When an 80% confidence criterion was applied, improvement or decline of 12 words in the total score (sum score: Trials 1-5) cannot be attributed to measurement error. These findings should help clinicians better understand cognitive side effects and facilitate decision making regarding changes to individual patient's psychopharmacotherapy.