Spanish version of the Screen for Cognitive Impairment in Psychiatry (SCIP-S): psychometric properties of a brief scale for cognitive evaluation in schizophrenia

Abstract

Objective: The Screen for Cognitive Impairment in Psychiatry (SCIP) is a brief scale designed for detecting cognitive deficits in several psychotic and affective disorders. This study examined the psychometric properties of the Spanish version of the SCIP in a sample of outpatients suffering schizophrenia-spectrum disorders.

Methods: Psychometric properties were evaluated in a sample of 126 stable patients with schizophrenia. Men and women 18 to 55 years of age were recruited from consecutive admissions to 40 psychiatric outpatient clinics in Spain and asked to complete a series of cognitive measures at baseline, as well as three versions of the SCIP separated by one week intervals. A matched sample of 39 healthy controls was also subjected to the baseline examination. The feasibility, reliability and validity of the SCIP was examined; concurrent validity was assessed by means of a complete neuropsychological battery.

Results: Average time for SCIP administration was 16.02 (SD=5.01) minutes. Test-retest reliability intra-class correlation coefficients ranged from 0.74 to 0.90, with an internal consistency Cronbach's alpha value of 0.73. The three parallel forms of SCIP were shown to be equivalent. The SCIP scales were correlated with corresponding neuropsychological instruments, with Pearson's r between 0.38 and 0.60, p<0.01. The SCIP effectively discriminated between the patient and control samples. Factor analysis revealed one significant dimension, cognitive performance, that accounted for 49.8% of the total variance.

Conclusions: The Spanish version of the SCIP is a simple, brief, valid and reliable tool for detection of cognitive impairment in patients with schizophrenia by minimally trained healthcare personnel.