Factor Structure of the Targeted Inventory on Problems in Schizophrenia

Tanaka, Shoji; Nagase, Takanori; Suzuki, Takefumi; Nomura, Kensuke; Takeuchi, Hiroyoshi; Nakajima, Shinichiro; Uchida, Hiroyuki; Yagi, Gohei; Watanabe, Koichiro; Mimura, Masaru

Abstract

OBJECTIVE
The aim of this study was to explore the factor structure of a novel, 10-item rating scale, the Targeted Inventory on Problems in Schizophrenia (TIP-Sz). Determining the factor structure will be useful in the brief evaluation of medication and non-medication treatment of the disease.
METHODS
An exploratory factor analysis was performed on TIP-Sz scores obtained from 100 patients who met the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria for schizophrenia.
RESULTS
The factor analysis extracted four factors that were deemed clinically pertinent, which we labeled: disorganization, social cooperativeness, functional capacity, and emotional state. The items exhibited cross-loadings on the first three factors (i.e., some items loaded on more than one factor). In particular, the 'behavioral dyscontrol and disorganization,' 'insight and reality testing,' and 'overall prognostic impression' items had comparable cross-loadings on all of the first three factors. The emotional state factor was distinct from the other factors in that the items loading on it did not cross-load on other factors.
CONCLUSION
The TIP-Sz scale comprises factors that are associated with the psychosocial functioning and emotional state of patients, which are important outcome parameters for successful treatment of the disease.