To the Editor: In examining the article by Robert Paul Liberman, M.D., and colleagues, I found many inaccuracies regarding the definition of occupational therapy and in the research design. First, I was surprised that no occupational therapist who contributed to the study was listed as coauthor. Second, the title of the study is misleading. The authors’ definition of psychosocial occupational therapy, "in which expressive art and crafts and recreational activities are the media" (p. 1087), is outdated. Psychosocial occupational therapists today use a holistic approach and purposeful activities to increase the individual’s repertoire of social and self-care skills, work behaviors, and leisure activities and use biofeedback, stress management, social skills training, exercise, and vocational exploration (1).

The next important issue deals with research methodology. Although 80 patients were assigned randomly to two groups, there were no assessments to determine that the groups were evenly matched regarding major variables of diagnosis or functional performance. We cannot assume that they were comparable groups without testing for equivalency. This would affect both internal and external validity.

Can another researcher replicate this study? In the psychosocial group, little detail was given regarding how the patients participated in the groups or individually. The skills training group did consist of modules and a trainer’s manual that can be replicated.

Another research problem that was identified by the investigators was the bias inherent in the treatment of case managers. The case managers were different for each group, and their personalities may have affected the results. This remains an uncontrolled variable. The patients did not have an opportunity to rate the interventions and to determine if they were helpful. Having the clients assess treatment gives them an opportunity to evaluate its usefulness and relevancy. We do not know how sensitive the instruments were for patient improvement. We do know that many of the tests used have moderate reliability and validity that introduces measurement error. An examination of the data reveals that many of the standard errors of measurement were as large as the means; that can be interpreted as a large discrepancy between scores. A case-by-case analysis should have been done to determine which of the patients improved significantly on the variables measured. A major flaw in the study was the conclusion in the abstract, which is most damaging when many investigators examining studies may only look at the abstract. The authors conclude that skills training conducted by paraprofessionals is more effective than providing occupational therapy services. Skills training was provided by an occupational therapist in this study. This study shows that independent living skills training is effective with individuals with schizophrenia—something we have known for 40 years. The conclusion tells us nothing about psychosocial occupational therapy.