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Published in: International Journal of Behavioral Medicine 4/2009

01-12-2009

Intention-to-Treat Analyses in Behavioral Medicine Randomized Clinical Trials

Authors: Sherry L. Pagoto, Andrea T. Kozak, Priya John, Jamie S. Bodenlos, Donald Hedeker, Bonnie Spring, Kristin L. Schneider

Published in: International Journal of Behavioral Medicine | Issue 4/2009

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Abstract

Background

Intention-to-treat (ITT) is an analytic approach where all randomized participants are included in analyses and in their originally assigned condition, regardless of adherence or protocol deviation.

Purpose

The present study aimed to determine whether reporting and correct use of ITT in behavioral medicine randomized clinical trials (RCTs) published in behavioral journals has improved in recent years.

Method

ITT and related analytic conventions were examined in behavioral medicine RCTs (N = 87) published in Annals of Behavioral Medicine, Health Psychology, and the Journal of Consulting and Clinical Psychology in the years 2000–2003 and then again in 2006–2007. Logistic regression analyses tested whether ten indicators associated with ITT were being used increasingly over time. Also tested was whether reporting and correct use of ITT improved following the adoption of Consolidated Standards of Reporting Clinical Trials (CONSORT) statement.

Results

Results revealed that less than half of RCTs (42%) used ITT analyses correctly. Over time, reporting of sample size estimation and primary outcome as well as use of the term “ITT” to describe analyses improved; however, correct implementation of ITT did not. Improvement was not specifically attributable to CONSORT adoption.

Conclusion

Investigators’ claims of using ITT analyses have increased over time, but correct use of ITT has not.
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Metadata
Title
Intention-to-Treat Analyses in Behavioral Medicine Randomized Clinical Trials
Authors
Sherry L. Pagoto
Andrea T. Kozak
Priya John
Jamie S. Bodenlos
Donald Hedeker
Bonnie Spring
Kristin L. Schneider
Publication date
01-12-2009
Publisher
Springer US
Published in
International Journal of Behavioral Medicine / Issue 4/2009
Print ISSN: 1070-5503
Electronic ISSN: 1532-7558
DOI
https://doi.org/10.1007/s12529-009-9039-3

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