Thornley, Ben, and Adams, Clive "Content and quality of 2000 controlled trials in schizophrenia over 50 years" British Medical Journal 1998; 317: 1181-1184.

Overview of research studies

• Studies published between 1948 and 1997.
• Patients with schizophrenia and other non-affective psychoses.

Variety of interventions

• Drugs (e.g., anti-psychotics and anti-depressants)
• Therapy (e.g., individual, group, and family)
• Miscellaneous (e.g., electroconvulsive treatments)

Four difficulties

1. Types of patients

• The ideal study would be community based.
• Only 14% of actual studies were community based.

2. Number of patients

• The ideal study should include at least 300 patients.
• The average number was only 65 patients.
• Only 3% of studies met the target of 300 or more patients.

3. Length of the studies

• The ideal study should last at least six months.
• More than half of the studies lasted six weeks or less.
• Only 19% of the studies met the target of six months or more duration.

4. Measurement

• The ideal studies should concentrate on a small number of standard measures.
• These studies employed 640 different measures.
• There were 369 measures that were used once and never used again.

Conclusions

Much of the work in schizophrenia failed to meet appropriate research standards. Too many of the studies...

• examined the wrong patients,
• studied too few patients,
• ended too soon,
• used fragmentary measurements.

Research in schizophrenia leaves much room for improvement.

This work is licensed under a Creative Commons Attribution 3.0 United States License. It was written by Steve Simon on 2000-05-04, edited by Steve Simon, and was last modified on 2008-01-11. This page needs minor revisions. Category: Statistical evidence