title: Longitudinal relationship between Personal and Social Performance (PSP) and anxiety symptoms in schizophrenia.
abstract: BACKGROUND
  We aimed to examine the longitudinal relationship between the personal and social functioning and anxiety symptoms in patients with schizophrenia. For this purpose, we confirmed the validity of the anxiety subscale of the Symptom-Checklist-90-Revised (SCL-90-R) and then applied the latent growth modeling method for longitudinal causal relationships.
  
  
  METHODS
  Five hundred and seventy-eight patients diagnosed with schizophrenia were evaluated and 369 patients were included in the study at baseline. After conducting Rasch model analyses for the validation of the anxiety subscale in the SCL-90-R, we applied latent growth model to determine the causal relationship between the PSP and the anxiety symptoms.
  
  
  RESULTS
  The validity of the anxiety subscale of the SCL-90-R was confirmed based on the Rasch rating model, where the criteria for Infit, Outfit, item difficulty, and point-measure correlations were satisfied. The results from the latent growth model showed that the intercept and slope (rate of change) of the PSP negatively predicted the slope of anxiety symptoms along the longitudinal trajectory. Together with previous studies examining the predictive role of anxiety symptoms on quality of life, our longitudinal findings lend evidence for bidirectional effects between quality of life and anxiety symptoms. The transactional nature of the relationship between anxiety symptoms and quality of life warrant further investigation using a longitudinal cross-lagged design.
  
  
  CONCLUSIONS
  The anxiety subscale of the SCL-90-R may be utilized by clinicians and researcher to make inferences about quality of life in addition to assessing anxiety symptoms in patients with schizophrenia.
authors.affiliation: Department of Psychology, Yonsei University, Seoul, Republic of Korea.
authors.forename: In-Jo
authors.initials: IJ
authors.lastname: Park
authors.affiliation: Department of Neuropsychiatry, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Dong
authors.initials: D
authors.lastname: Chung Jung
authors.affiliation: Department of Psychology, Chonnam National University, Gwangju, Republic of Korea.
authors.forename: Samuel
authors.initials: S
authors.lastname: Suk-Hyun Hwang
authors.affiliation: Institute of Human Behavioral Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Psychiatry, SMG-SNUBoramae Medical Center, Seoul, South Korea.
authors.forename: Hee
authors.initials: H
authors.lastname: Yeon Jung
authors.affiliation: Department of Psychiatry, Chonnam National University Medical School, Gwangju, Republic of Korea.
authors.forename: Jin-Sang
authors.initials: JS
authors.lastname: Yoon
authors.affiliation: Department of Psychiatry, Inha University Hospital, Incheon, Republic of Korea.
authors.forename: Chul-Eung
authors.initials: CE
authors.lastname: Kim
authors.affiliation: Department of Psychology, Yonsei University, Seoul, Republic of Korea; Institute of Human Behavioral Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea. Electronic address: aym@snu.ac.kr.
authors.forename: Yong
authors.initials: Y
authors.lastname: Min Ahn
authors.affiliation: Department of Psychiatry, Dongguk University Ilsan Hospital, Goyang, Republic of Korea; Institute of Clinical Psychopharmacology, Dongguk University Ilsan Hospital, Goyang, Republic of Korea. Electronic address: kys@snu.ac.kr.
authors.forename: Yong
authors.initials: Y
authors.lastname: Sik Kim
mesh_terms: D000328:Adult; D000368:Aged; D001007:Anxiety / Q000150:complications* / Q000175:diagnosis* / Q000523:psychology; D002986:Clinical Trials as Topic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D011788:Quality of Life; D012559:Schizophrenia / Q000150:complications* / Q000175:diagnosis* / Q000188:drug therapy; D012565:Schizophrenic Psychology; D012917:Social Adjustment
keywords: Anxiety symptoms; Latent growth model; Longitudinal relationship; Personal and Social Performance; Rasch rating model; SCL-90-R