Research Article| Volume 53, ISSUE 2, P73-78, March 2005

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Participant-centered adaptations in caregiver trials: Strategies for managing confounds


      Randomized trials have been criticized for being more protocol than participant-centered, with concerns raised about higher subject attrition and limited generalizability under controlled conditions. Informal caregivers are similar to other participants in community-based trials: many are unlikely to remain in a trial without procedural adaptations to meet some of their needs.


      This article discusses design and statistical strategies for tracking potential confounds associated with 3 participant-centered adaptations that may be made in community-based caregiver trials: tailoring multi-component interventions, using interpersonal contacts for participant maintenance, and non-blinding of trial participants. The intent of the article is to initiate dialogue on the seldom-discussed issue of participant-centered adaptations in community-based trials.


      Participant-centered adaptations may reduce subject attrition and enhance generalizability, but protocol adaptation can compromise trial integrity. The challenge for investigators is to develop scientifically sound methods for tracking / controlling potential confounds associated with each adaptation.
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      1. University of Alabama at Birmingham. Project ASSIST for Chronic Illness Caregiver (5 RO1 NR008285). Year 2 ROGRESS REPORT SUMMARY: Submitted May, 2004 to National Institute of Nursing Research. Principal Investigator: Linda Lindsey Davis.


      Linda Lindsey Davis is at the School of Nursing, Duke University, Durham, NC.


      Michael Weaver is a Professor, School of Nursing and Department of Biostatistics, at the University of Alabama at Birmingham, Birmingham, AL.


      Barbara Habermann is an Assistant Professor, School of Nursing, and a Scientist, Center for Aging, at the University of Alabama at Birmingham, Birmingham, AL.


      Kathleen Buckwalter is a Professor, College of Nursing, and Associate Provost for Health Sciences at the University of Iowa, Iowa City, IA.