Study designs of evaluations included in the review
The included studies were double-blind trials comparing risperidone with another antipsychotic or a placebo. The duration of the trials ranged from 4 to 12 weeks.
Specific interventions included in the review
The included studies compared risperidone to either another antipsychotic or a placebo. Risperidone was given in doses ranging from 2 to 20 mg daily. The other antipsychotics studied were haloperidol, perphenazine and clozapine at daily doses ranging from 2 to 20 mg, 16 to 48 mg, and 400 mg, respectively.
Participants included in the review
Patients diagnosed as having acute schizophrenia as defined by the American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders (DSM-111-R) or International Classification for Diseases (ICD-9). Male and female patients of both white and Asian origin were included. The mean age ranged from 34 to 39 years across trials, with duration of illness being up to 16 years, and with patients having had up to 9 prior episodes of illness. The mean psychopathology score at study entry ranged from 44 to 55 on the Brief Psychiatric Rating Scale (BPRS) or from 85 to 94 on the Positive and Negative Syndrome Scale (PANSS). In-patients were included.
Outcomes assessed in the review
The main outcomes assessed were the efficacy of treatment and extrapyramidal, autonomic and central nervous system side-effects. The efficacy of treatment was assessed using the following measures: BPRS, documentation system for the Association for Methodology and Documentation in Psychiatry (AMPD), PANSS, Scale for the Assessment of Negative Symptoms (SANS), Clinical Global Impressions (CGI), Nurses Observation Scale for Inpatient Evaluation (NOSIE-30), Schedule for Affective Disorders and Schizophrenia-Current Version (SADS-C). Side-effects were assessed using the following measures: DVP side-effects rating scale, Extrapyramidal Symptom Rating Scale (ESRSA), Udvalg for Kliniske Undersogelser Side Effect Rating Scale (UKU) and the Abnormal Involuntary Movement Scale (AIMS).
How were decisions on the relevance of primary studies made?
The authors do not state how the papers were selected for review, or how many of the authors performed the selection.