Psychiatric Quarterly

, Volume 79, Issue 2, pp 111–119 | Cite as

Comparison of Clozapine Response for Inpatients in the Research Setting Versus Routine Clinical Practice

  • Douglas L. Boggs
  • Deanna L. Kelly
  • Raymond C. Love
  • Robert P. McMahon
  • Robert R. Conley
Original Paper



This study compares patient characteristics and treatment response between inpatients treated with clozapine in a research setting as compared to those initiated on clozapine during routine inpatient treatment.


Subjects on clozapine, in clinical trials, were compared with clozapine inpatients receiving routine clinical care.


At baseline, patients in routine clinical practice had more negative symptoms (P < 0.001), activation (P < 0.001) and greater total Brief Psychiatric Rating Scale (BPRS) scores (P = 0.022) than those in the research setting. Routine clinical practice subjects had larger decreases in BPRS total scores (P = 0.042) and positive item scores (P = 0.0005) compared to research subjects. Response to clozapine was observed in 15/85 (18%) research subjects as compared to 60/223 (27%) patients in routine care (P = 0.09).


Patients treated in routine clinical practice have more severe baseline symptoms, but experience significantly greater improvements in psychiatric symptoms.


Clozapine Effectiveness Treatment refractory Schizophrenia 



The authors would like to thank Yang Yu, M.S. for the help with data analysis. They would also thank the members of the Treatment Research Program for their help in the research involved in this publication. This work was supported in part by the Advanced Center for Intervention and Services Research Grant (P50 MH40279, Carpenter WT Jr, PI).

Conflict of Interest and Financial Support Statement

Douglas L. Boggs: no competing interests or financial support to disclose. Deanna L. Kelly: grant support; Abbott, Astra-Zeneca; honoraria; Astra-Zeneca; Advisory Board; Solvay, Bristol-Meyers Squibb; Raymond C. Love: Speaker; Bristol-Meyers Squibb; Robert P. McMahon: no competing interests or financial support to disclose; Robert R. Conley: Advisory Board: Astra-Zeneca, Bristol-Meyers Squibb, Janssen, Johnson & Johnson, Eli Lilly, Organon, Pfizer, Solvay, Wyeth.


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Douglas L. Boggs
    • 1
  • Deanna L. Kelly
    • 1
  • Raymond C. Love
    • 2
  • Robert P. McMahon
    • 1
  • Robert R. Conley
    • 1
  1. 1.Maryland Psychiatric Research CenterUniversity of Maryland Baltimore, School of MedicineBaltimoreUSA
  2. 2.University of Maryland Baltimore, School of PharmacyBaltimoreUSA

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