Incremental Validity between the Wartegg and Rorschach tests (R-PAS)

Abstract

Incremental validity indicates how much a measure can add prevision to a criterion, more than what can be previewed by other sources of data. In other words, it means how an instrument can complement and aid on information comprehension derived from another. The objective of the study was to verify evidence of incremental validity between the Wartegg and the Rorschach tests (R-PAS). A total of 40 subjects with ages varying between 21 to 70 years participated, divided into two groups, one composed by schizophrenia diagnosis and another, by subjects with a history of psychiatric diseases. Everybody responded to the Rorschach and Wartegg tests. The results indicated predictive capacity among the instruments of 75% for the variable Formal Quality, 98% for Movement and 100% for Content. New studies are suggested about validity evidences with larger samples as well as the analysis of other variables, not explored in this study.