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Design and analysis of clinical trials with clustering effects due to treatment
Abstract
Where patients receive therapy as a group, there are good theoretical reasons to believe that variation in the outcome will be smaller for patients treated in the same group than for patients treated in different groups. Similarly, where different therapists treat different groups of patients, outcome for patients treated by the same therapist may differ less than outcome for patients treated by different therapists. Clinical trials evaluating such therapies need to consider this potential lack of independence. As with cluster-randomized trials, this has implications for the precision of treatment effects estimates and statistical power. There are nevertheless differences between clustering due to the organization of treatment and that due to randomization. In cluster-randomized trials the distribution of cluster sizes in each treatment arm should be similar as a consequence of randomization unless there is differential loss to follow-up. With clustering due to therapy group or therapist, cluster size may differ systematically between treatment arms, due to size of therapy groups or differing health professional caseload. Intra-cluster correlation may also differ between treatment arms. The implications of differential cluster size and intracluster correlation for design and analysis will be illustrated by data from two trials, the first comparing nurse practitioner care with general practitioner care, and the second comparing a group therapy with individual treatment as usua…
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“To allow for potential clustering effects in the intervention arm we used an allocation ratio of 2:1 (intervention: treatment as usual).18”
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“Based on an average cluster size of 13 evaluable participants (those completing 3 months follow-up), and a therapist (health professional delivering the intervention) intraclass correlation coefficient of 0.05(ref. 30) in the intervention arm, a total of 364 evaluable patients at 3 months would provide 92% power to detect such a difference with a two-sample test and a significance level of 5%.31”
From A brief intervention for weight control based on habit-formation theory delivered through primary care: results from a randomised controlled trial (2017) · cites this paper as [31]
Citations
Cites
The Positive and Negative Syndrome Scale (PANSS) for schizophrenia.
Kay, S. R., Fiszbein, A., & Opler, L. A. (1987) · Schizophrenia Bulletin · doi:10.1093/schbul/13.2.261 · Cited by 21,378
Longitudinal data analysis using generalized linear models
LIANG, K.-Y., & ZEGER, S. L. (1986) · Biometrika · doi:10.1093/biomet/73.1.13 · Cited by 18,550
Mixed-Effects Models in Sand S-PLUS
Pinheiro, J. C., & Bates, D. M. (2000) · Statistics and Computing · doi:10.1007/978-1-4419-0318-1 · Cited by 11,187
Mixed-Effects Models in S and S-PLUS
(2001) · Technometrics · doi:10.1198/tech.2001.s574 · Cited by 9,278
An Approximate Distribution of Estimates of Variance Components
Satterthwaite, F. E. (1946) · Biometrics Bulletin · doi:10.2307/3002019 · Cited by 4,373
Design and Analysis of Cluster Randomization Trials in Health Research
Davis, W. W. (2001) · Journal of the American Statistical Association · doi:10.1198/jasa.2001.s433 · Cited by 1,735
Design and Analysis of Cluster Randomization Trials in Health Research
DONNER, A. P., & Klar, N. S. (2000) · Cited by 1,236
Models of Non-Independence in Dyadic Research
Kenny, D. A. (1996) · Journal of Social and Personal Relationships · doi:10.1177/0265407596132007 · Cited by 973
Contamination in trials: is cluster randomisation the answer?
Torgerson, D. J. (2001) · BMJ · doi:10.1136/bmj.322.7282.355 · Cited by 508
Venning, P. (2000) · BMJ · doi:10.1136/bmj.320.7241.1048 · Cited by 494
The statistical analysis of data from small groups.
Kenny, D. A., Mannetti, L., Pierro, A., Livi, S., & Kashy, D. A. (2002) · Journal of Personality and Social Psychology · doi:10.1037/0022-3514.83.1.126 · Cited by 470
Meta‐Analysis of Therapist Effects in Psychotherapy Outcome Studies
Crits-Christoph, P. F., Baranackie, K., Kurcias, J., Beck, A. T., Carroll, K. M., Perry, K. J., Luborsky, L. B., McLellan, A. T., WOODY, G. E., Thompson, L. W., et al. (1991) · Psychotherapy Research · doi:10.1080/10503309112331335511 · Cited by 433
Crits-Christoph, P. F., & Mintz, J. (1991) · Journal of Consulting and Clinical Psychology · doi:10.1037//0022-006x.59.1.20 · Cited by 413
Wolf, M. H., Putnam, S. M., James, S. A., & Stiles, W. B. (1978) · Journal of Behavioral Medicine · doi:10.1007/bf00846695 · Cited by 386
Giesbrecht, F. G., & Burns, J. C. (1985) · Biometrics · doi:10.2307/2530872 · Cited by 207
The consequence of ignoring a nested factor on measures of effect size in analysis of variance.
Wampold, B. E., & Serlin, R. C. (2000) · Psychological Methods · doi:10.1037/1082-989x.5.4.425 · Cited by 186
The two-sample t test versus satterthwaite's approximate f test
Moser, B. K., Stevens, G. R., & Watts, C. L. (1989) · Communication in Statistics- Theory and Methods · doi:10.1080/03610928908830135 · Cited by 161
Are distinctive ethical principles required for cluster randomized controlled trials?
Hutton, J. L. (2001) · Statistics in Medicine · doi:10.1002/1097-0258(20010215)20:3 · Cited by 125
Parent Satisfaction With Children??s Medical Care
Lewis, C., Scott, D. E., Pantell, R. H., & Wolf, M. H. (1986) · Medical Care · doi:10.1097/00005650-198603000-00003 · Cited by 89
A Monte Carlo Study of Alternative Responses To Intraclass Correlation in Community Trials
Murray, D. M., Hannan, P. J., & Baker, W. L. (1996) · Evaluation Review · doi:10.1177/0193841x9602000305 · Cited by 85
Roberts, C. (1999) · Statistics in Medicine · doi:10.1002/(sici)1097-0258(19991015)18:19 · Cited by 79
Self-citationThe therapist-as-fixed-effect fallacy in psychotherapy research.
Martindale, C. (1978) · Journal of Consulting and Clinical Psychology · doi:10.1037/0022-006x.46.6.1526 · Cited by 73
Serlin, R. C., Wampold, B. E., & Levin, J. R. (2003) · Psychological Methods · doi:10.1037/1082-989x.8.4.524 · Cited by 58
Analyzing data from individuals in groups: The past, the present, and the future.
Hoyle, R. H., Georgesen, J. C., & Webster, J. M. (2001) · Group Dynamics Theory Research and Practice · doi:10.1037/1089-2699.5.1.41 · Cited by 48
Power and measures of effect size in analysis of variance with fixed versus random nested factors.
Siemer, M., & Joormann, J. (2003) · Psychological methods · doi:10.1037/1082-989x.8.4.497 · Cited by 43
Group dynamics and individual performances: Pseudogroup and quasi-F analyses.
Myers, J. L., DiCecco, J. V., & Lorch, R. F. (1981) · Journal of Personality and Social Psychology · doi:10.1037/0022-3514.40.1.86 · Cited by 40
Siqueland, L., Crits-Christoph, P. F., Barber, J. P., Butler, S. F., Thase, M. E., Najavits, L. M., & Onken, L. S. (2000) · PubMed Central · Cited by 34
Clinical trials of behavioural interventions with heterogeneous teaching subgroup effects
Hoover, D. R. (2002) · Statistics in Medicine · doi:10.1002/sim.1139 · Cited by 34
Crits-Christoph, P. F., Tu, X. M., & Gallop, R. (2003) · Psychological Methods · doi:10.1037/1082-989x.8.4.518 · Cited by 32
A comparison of power approximations for satterthwaite's test
DiSantostefano, R. L., & Muller, K. E. (1995) · Communications in Statistics - Simulation and Computation · doi:10.1080/03610919508813260 · Cited by 16
Research works printed but not linked: 8
- Murray DM, 1998, Design and analysis of group-randomised trials
- Stead LF, 2004, The Cochrane Collaboration: The Cochrane Library, Issue 2
- 10.1037/0022-006X.59.1.20 · DOI
- Barrowclough C, 2004, A multi-site evaluation of the effectiveness of group cognitive behaviour therapy for schizophrenia
- Rasbash J, 2001, ML Win version 1.10
- R Foundation for Statistical Computing, 2004, A language and environment for statistical computing - R Development Core Team
- Elashof JD, Nquery Advisor Version 5.0 User's Guide
- Siqueland L, 2000, J Psychother Prac Res, 9, 123
Cited by
Sorted by citations
Consort 2010 statement: extension to cluster randomised trials
Campbell, M. K., Piaggio, G., Elbourne, D. R., Altman, D. G., & for the CONSORT Group (2012) · BMJ · doi:10.1136/bmj.e5661 · Cited by 3,510
Boutron, I., Moher, D., Altman, D. G., Schulz, K. F., Ravaud, P., & for the CONSORT Group* (2008) · Annals of Internal Medicine · doi:10.7326/0003-4819-148-4-200802190-00008 · Cited by 2,292
Boutron, I., Altman, D. G., Moher, D., Schulz, K. F., Ravaud, P., & for the CONSORT NPT Group* (2017) · Annals of Internal Medicine · doi:10.7326/m17-0046 · Cited by 1,538
When Should You Adjust Standard Errors for Clustering?
Abadie, A., Athey, S. C., Imbens, G. W., & Wooldridge, J. M. (2017) · National Bureau of Economic Research · doi:10.3386/w24003 · Cited by 1,409
Kessler, D., Lewis, G., Kaur, S., Wiles, N., King, M., Weich, S., Sharp, D. J., Araya, R., Hollinghurst, S., & Peters, T. J. (2009) · The Lancet · doi:10.1016/s0140-6736(09)61257-5 · Cited by 387
Metadata
- Authors
- Roberts, C., & Roberts, S. A.
- Affiliations
- University of Manchester (GB)
- Corresponding author
- Roberts, Chris
- ORCID
- Roberts, Stephen A
- Venue
- Clinical Trials
- Publisher
- SAGE Publications
- Published
- 2005-04
- Volume
- 2
- Issue
- 2
- Pages
- 152-162
- ISSN
- 1740-7745 (ISSN-L)
- 1740-7753
- OpenAlex
- W2093029291
- Cited by
- 299
- References
- 30
- Citations by year
- 2026: 8 · 2025: 14 · 2024: 16 · 2023: 18 · 2022: 14 · 2021: 23 · 2020: 33 · 2019: 23 · 2018: 13 · 2017: 11 · 2016: 14 · 2015: 12 · 2014: 22 · 2013: 12 · 2012: 17
- FWCI
- 4.50
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Clinical Trials (publishedVersion)
- PubMed (publishedVersion)
- Research Explorer (The University of Manchester) (submittedVersion)
- Topics
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods and Bayesian Inference
- Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
- Keywords
- cluster effect, group therapy, therapist effects, intra-cluster correlation, statistical power, sample size, general practitioner care, simulation study
- MeSH terms
- Data Interpretation, Statistical, Group Processes, Humans, Nurse Practitioners, Physicians, Family, Research Design, Statistics as Topic, Cluster Analysis, Randomized Controlled Trials as Topic, Treatment Outcome, Sample Size
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