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A Qualitative Study to Understand Barriers to Conducting Cluster Randomized Trials

Research Report Dec 2, 2009

Page Contents

Findings from this study were published in the following journal articles.

1. Mazor KM, Sabin JE, Boudreau D, Goodman MJ, Gurwitz JH, Herrinton LJ, Raebel MA, Roblin D, Smith DH, Meterko V, Platt R. Cluster randomized trials: opportunities and barriers identified by leaders of eight health plans. Med Care. 2007 Oct; 45 (10 Supl 2): S29-37.



Cluster randomized trials (CRTs) offer unique advantages over standard randomized controlled clinical trials (RCTs) and observational methodologies, and may provide a cost-efficient alternative for answering questions about the best treatments for common conditions.


To describe health plan leaders' views on CRTs, identify barriers to conducting CRTs, and solicit recommendations for increasing the acceptability of CRTs.

Research design

Qualitative in-depth telephone interviews with leaders from 8 health plans.


Thirty-four health plan leaders (medical directors, pharmacy directors, Institutional Review Board leaders, ethics leaders, compliance leaders, and others).


Qualitative analysis of interview transcripts to identify barriers, factors influencing leaders' views, ethical issues, aspects of CRTs that appeal to leaders, and recommendations for increasing acceptability of CRTs.


Multiple barriers were identified, including financial costs, concerns about stakeholders' perceptions of CRTs, impact on physicians' prescribing habits, and formulary changes. Most leaders recognized the potential value of studying the comparative effectiveness of therapeutics, and many stressed the need for head-to-head trials. Leaders' views would be influenced by variations in study design and implementation. Recommendations for increasing acceptability of CRTs included ensuring that the fiscal impact of a CRT be budget neutral, and that researchers educate stakeholders and decision-makers about CRTs.


Overall, health plan leaders recognized the need for studies of the comparative effectiveness of therapeutics under real world conditions, and many expressed support for CRTs. However, researchers seeking to conduct CRTs in health plans are likely to face numerous barriers, and preparatory work will be essential.

2. Mazor KM, Sabin JE, Goff SL, Smith DH, Rolnick S, Roblin D, Raebel MA, Herrinton LJ, Gurwitz JH, Boudreau D, Meterko V, Dodd KS, Platt R. Cluster randomized trials to study the comparative effectiveness of therapeutics: stakeholders' concerns and recommendations. Pharmacoepidemiol Drug Saf. 2009 Apr 28.



To describe the concerns raised by health plan members, providers and purchasers related to studying the comparative effectiveness of therapeutics using cluster randomized trials (CRTs) within health plans. An additional goal was to develop recommendations for increasing acceptability.


Eighty-four qualitative in-depth telephone interviews were conducted; 50 with health plan members, 21 with providers, and 13 with purchasers. Interviews focused on stakeholders' concerns about and recommendations for conducting CRTs in health plans.


Members expressed concerns that CRTs might compromise their healthcare. Providers and purchasers recognized the value of and the need for comparative effectiveness research. Providers expressed concerns that they would not have sufficient time to discuss a CRT with patients, and that participation in such a study could negatively impact their relationships with patients. Purchasers would want assurances that study participation would not result in members receiving lesser care, and that benefits would remain equitable for all members.


This study provides insight into how health plan members, providers and purchasers might react to a CRT being conducted in their health plan. The recommendations reported here provide guidance for researchers and policy makers considering this methodological approach and suggest that with sufficient preparation and planning CRTs can be an acceptable and efficient methodology for studying the comparative effectiveness of therapeutics in real world settings.

Project Timeline

A Qualitative Study to Understand Barriers to Conducting Cluster Randomized Trials

Jan 1, 2005
Topic Initiated
Dec 2, 2009
Research Report
Page last reviewed November 2017
Page originally created November 2017

Internet Citation: Research Report: A Qualitative Study to Understand Barriers to Conducting Cluster Randomized Trials. Content last reviewed November 2017. Effective Health Care Program, Agency for Healthcare Research and Quality, Rockville, MD.

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