Trial Outcomes & Findings for Risperidone Treatment in Schizophrenia Patients Who Are Currently Taking Clozapine (NCT NCT00056498)

Though funding was in place beginning in 2001, recruitment took place from 2003 to 2008. Subjects were recruited from the Maryland Psychiatric Research Center Outpatient Reseach clinic, the Treatment Research Program, and community mental health centers.

86 Participants signed informed consent. 15 were ineligible or excluded. 71 Participants entered the evaluation phase. Two were withdrawn prior to randomization. Four people withdrew after randomization but prior to starting study medications.

Risperidone Treatment in Schizophrenia Patients Who Are Currently Taking Clozapine

The Brief Psychiatric Rating Scale (BPRS) positive symptom items are: conceptual disorganization, hallucinatory behavior, unusual thought content, and suspiciousness. The total score is calculated by adding the scores for each item. Each scale ranges from "1=Not Present" to "7=Very Severe". The minimum score is 4 and the maximum score is 28. A higher score indicates a more severe positive symptom rating. A mixed model for unbalanced repeated measures analysis of covariance (ANCOVA), in which follow-up symptom score = baseline symptom score + treatment + week + treatment x week, and week is treated as a categorical, rather than a continuous measure. The treatment term estimates the average across weeks of the week-specific group differences, and is used as the main test for treatment effects on symptom change.

The neuropsychological testing measured attention, executive function/problem solving, motor speed, processing speed/response generation, and verbal, visual, and working memory. The individual test raw scores were converted to z-scores and an overall composite z-score was computed from the average of the individual test z-scores. Z-scores range from -3 standard deviations up to +3 standard deviations. Higher scores indicate better test performance.

The Scale for the Assessment of Negative Symptoms (SANS) total score, minus the global items, inappropriate affect, poverty of content of speech, and attention items, used to measure negative symptoms. SANS total score range = 0-85. Higher scores indicate more severe negative symptoms. A mixed model for unbalanced repeated measures analysis of covariance (ANCOVA), in which follow-up symptom score = baseline symptom score + treatment + week + treatment x week, and week is treated as a categorical, rather than a continuous measure. The treatment term estimates the average across weeks of the week-specific group differences, and is used as the main test for treatment effects on symptom change.