Validity and utility of a set of clinical criteria for cognitive impairment associated with psychosis (CIAPs)

Schizophrenia and other psychoses display a common profile of mild to moderate cognitive deficits that are associated with poor functional outcomes. Cognitive impairment is usually evaluated by neuropsychological assessment, and interview-based measures with good psychometric properties and high utility for clinical practice are now available. However, the extent to which a set of clinical criteria can be used as proxy measures of cognitive deficits in this population has not been tested. This study aimed to examine the empirical validity of a set of clinical criteria for cognitive impairment associated with psychosis (CIAPs). Ninety-eight patients with non-pure affective psychosis and 50 healthy-matched controls were included. The CIAPs criteria were empirically tested against antecedent, concurrent and outcome validators and by means of a neuropsychological evaluation based on MATRICS Consensus Cognitive Battery (MCCB). The CIAPs criteria showed strong associations with outcomes and certain antecedent validators and moderate associations with concurrent validators. The CIAPs criteria achieved superior neuropsychological validity compared to current DSM 5 criteria for schizophrenia, the B-criterion of DSM 5 schizophrenia or a combination of both criteria. Cognitive impairment associated with psychosis can be clinically assessed and is a useful tool for clinical practice and predicting outcomes of schizophrenia and related psychosis.