The mini-mental state examination:
MMSE52 (30 points from seven categories), while time-friendly, has not been widely utilized and might be somewhat rough to evaluate cognition in schizophrenia. This topic is extensively reviewed elsewhere (e.g., in the National Institute of Mental Health’s Measurement and Treatment Research to Improve Cognition in Schizophrenia: MATRICS53). The MATRICS battery consists of 10 tests that represent seven cognitive domains and the time for completion is estimated to be about 65 minutes.
Other briefer scales include the Repeatable Battery for the Assessment of Neuropsychological Status: RBANS54 which is reported to take <30 minutes, and the brief assessment of cognition in schizophrenia: BACS55 which needs <35 minutes to evaluate. Important issues, apart from time burden, are whether stability (as an intermediate or endophenotype) versus changeability in cognition is to be assumed, and how a change in cognitive test scores translates into actual outcome in other domains of the illness. Also, it would be useful to have a concept of ‘responder’ (or treatment-resistance) as has been defined with a ≥20% decrease in the PANSS score and so forth (Suzuki et al., revision submitted).