Demographic characteristics, treatment history, presenting psychopathology and early course in schizophrenia. Treatment Strategies in Schizophrenia Collaborative Study Group
Hargreaves, W.A.; Kane, J.M.; Ninan, P.T.; Severe, J.B.; Woerner, M.
Psychopharmacology Bulletin 25(3): 340-343
1989
ISSN/ISBN: 0048-5764 PMID: 2626512 Document Number: 341478
Subject heterogeneity increases generalizability of study findings so long as site differences do not interact with treatment effects. Of 51 baseline characteristics of 234 patients, 31 show significant site differences. Of 33 baseline demographic, treatment history, and presenting symptom items, site differences were seen on 16. This heterogeneity emphasizes the importance of examining site interactions with other effects. The first opportunity to examine such interactions is in the prediction of patient stabilization following the index acute episode. Among the 33 demographic, treatment history, and presenting symptom variables, 11 significantly predicted this short-term outcome. Only 2 of these 33 variables showed site-by-baseline interactions in predicting stabilization, most likely due to chance sampling fluctuations. Thus, site heterogeneity is adding generality without confounding the predictions.