SF-36 scales, and simple sums of scales, were reliable quality-of-life summaries for patients with schizophrenia.
OBJECTIVE
To examine the feasibility and reliability of the Medical Outcomes Study 36 Item Short Form Health Survey (SF-36) for patients with schizophrenia, focusing on the eight scales and various aggregate summary measures.


METHODS
Secondary analysis of data from the European multicenter QUATRO medication adherence trial and the Regional Psychosis Project from The Netherlands. Methods included exploratory and confirmatory factor analyses and estimation of aggregate score reliability using Cronbach's alpha and Tarkkonen's generalized reliability index. The aggregate scores that were compared included two sets based on factor analyses, the standard "physical and mental health component summary scores" (PCS and MCS) and scores based on the original conceptual model of the SF-36 (simple sum of first four scales for physical health, last four for mental health).


RESULTS
The eight SF-36 scales were feasible to administer and reliable. Factor analyses of the QUATRO baseline scale data suggested two or three factors, the latter solution including a general "role limitation" factor. Aggregate scores based on the conceptual model had the highest generalized reliability of those compared.


CONCLUSIONS
SF-36 scales are suitable for patients with schizophrenia. Aggregate scores based on the conceptual model may be preferable to the MCS and PCS for such patients. Further investigation of factor structure is advisable.
Leese
Morven
M
Health Services and Population Research Department, Institute of Psychiatry, King's College London, De Crespigny Park, London SE5 8AF, UK. m.leese@iop.kcl.ac.uk
Schene
Aart
A
Koeter
Maarten
M
Meijer
Karin
K
Bindman
Jonathan
J
Mazzi
Mariangela
M
Puschner
Bernd
B
Burti
Lorenzo
L
Becker
Thomas
T
Moreno
Mauricio
M
Celani
Daniela
D
White
Ian R
IR
Thonicroft
Graham
G
D000293:Adolescent; D000328:Adult; D000368:Aged; D004812:Epidemiologic Methods; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics; D011788:Quality of Life; D012559:Schizophrenia / Q000534:rehabilitation*; D012565:Schizophrenic Psychology