Reporting of stepped wedge cluster randomised trials: extension of the CONSORT 2010 statement with explanation and elaboration

Karla Hemming, Monica Taljaard, Joanne E McKenzie, Richard Hooper, Andrew Copas, Jennifer A Thompson, Mary Dixon-Woods, Adrian Aldcroft, Adelaide Doussau, Michael Grayling, Caroline Kristunas, Cory E Goldstein, Marion K Campbell, Alan Girling, Sandra Eldridge, Mike J Campbell, Richard J Lilford, Charles Weijer, Andrew B Forbes, Jeremy M Grimshaw, Karla Hemming, Monica Taljaard, Joanne E McKenzie, Richard Hooper, Andrew Copas, Jennifer A Thompson, Mary Dixon-Woods, Adrian Aldcroft, Adelaide Doussau, Michael Grayling, Caroline Kristunas, Cory E Goldstein, Marion K Campbell, Alan Girling, Sandra Eldridge, Mike J Campbell, Richard J Lilford, Charles Weijer, Andrew B Forbes, Jeremy M Grimshaw

Abstract

This report presents the Consolidated Standards of Reporting Trials (CONSORT) extension for the stepped wedge cluster randomised trial (SW-CRT). The SW-CRT involves randomisation of clusters to different sequences that dictate the order (or timing) at which each cluster will switch to the intervention condition. The statement was developed to allow for the unique characteristics of this increasingly used study design. The guideline was developed using a Delphi survey and consensus meeting; and is informed by the CONSORT statements for individual and cluster randomised trials. Reporting items along with explanations and examples are provided. We include a glossary of terms, and explore the key properties of the SW-CRT which require special consideration in their reporting.

Conflict of interest statement

Competing interests: We have read and understood the BMJ Group policy on declaration of interests and declare the following interests: none. Provenance and peer review: Not commissioned; externally peer reviewed.

Figures

Fig 1
Fig 1
Diagram of the standard stepped wedge cluster randomised trial. Note that in designs where participants are measured after a follow-up time from their exposure, then the periods and their representations are defined based on when an individual was exposed and not when measured
Fig 2
Fig 2
Example of a diagram of a stepped wedge cluster randomised trial (SW-CRT) from the Riverbank Filtration Trial. Adapted from figure 2 in McGuinness SL, O’Toole JE, Boving TB, et al. Protocol for a cluster randomised stepped wedge trial assessing the impact of a community-level hygiene intervention and a water intervention using riverbank filtration technology on diarrhoeal prevalence in India. BMJ Open 2017;7:e015036. doi:10.1136/bmjopen-2016-015036. PubMed PMID:28314746; PubMed Central PMCID:PMC5372111.
Fig 3
Fig 3
Specimen flowchart for a stepped wedge cluster randomised trial (SW-CRT) by allocated sequence and period

References

    1. Begg C, Cho M, Eastwood S, et al. Improving the quality of reporting of randomized controlled trials. The CONSORT statement. JAMA 1996;276:637-9. 10.1001/jama.1996.03540080059030
    1. Rennie D. CONSORT revised--improving the reporting of randomized trials. JAMA 2001;285:2006-7. 10.1001/jama.285.15.2006
    1. Schulz KF, Altman DG, Moher D, CONSORT Group CONSORT 2010 statement: updated guidelines for reporting parallel group randomised trials. BMJ 2010;340:c332. 10.1136/bmj.c332
    1. Campbell MK, Elbourne DR, Altman DG, CONSORT group CONSORT statement: extension to cluster randomised trials. BMJ 2004;328:702-8. 10.1136/bmj.328.7441.702
    1. Campbell MK, Piaggio G, Elbourne DR, Altman DG, CONSORT Group Consort 2010 statement: extension to cluster randomised trials. BMJ 2012;345:e5661. 10.1136/bmj.e5661
    1. Brown CA, Lilford RJ. The stepped wedge trial design: a systematic review. BMC Med Res Methodol 2006;6:54. 10.1186/1471-2288-6-54
    1. Mdege ND, Man MS, Taylor Nee Brown CA, Torgerson DJ. Systematic review of stepped wedge cluster randomized trials shows that design is particularly used to evaluate interventions during routine implementation. J Clin Epidemiol 2011;64:936-48. 10.1016/j.jclinepi.2010.12.003
    1. Martin J, Taljaard M, Girling A, Hemming K. Systematic review finds major deficiencies in sample size methodology and reporting for stepped-wedge cluster randomised trials. BMJ Open 2016;6:e010166. 10.1136/bmjopen-2015-010166
    1. Hemming K, Haines TP, Chilton PJ, Girling AJ, Lilford RJ. The stepped wedge cluster randomised trial: rationale, design, analysis, and reporting. BMJ 2015;350:h391. 10.1136/bmj.h391
    1. Hemming K, Taljaard M, Forbes A. Analysis of cluster randomised stepped wedge trials with repeated cross-sectional samples. Trials 2017;18:101. 10.1186/s13063-017-1833-7
    1. Girling AJ, Hemming K. Statistical efficiency and optimal design for stepped cluster studies under linear mixed effects models. Stat Med 2016;35:2149-66. 10.1002/sim.6850
    1. Hooper R, Teerenstra S, de Hoop E, Eldridge S. Sample size calculation for stepped wedge and other longitudinal cluster randomised trials. Stat Med 2016;35:4718-28. 10.1002/sim.7028
    1. Kasza J, Hemming K, Hooper R, Matthews J, Forbes AB, ANZICS Centre for Outcomes & Resource Evaluation (CORE) Committee Impact of non-uniform correlation structure on sample size and power in multiple-period cluster randomised trials. Stat Methods Med Res 2017; 962280217734981.
    1. Copas AJ, Lewis JJ, Thompson JA, Davey C, Baio G, Hargreaves JR. Designing a stepped wedge trial: three main designs, carry-over effects and randomisation approaches. Trials 2015;16:352. 10.1186/s13063-015-0842-7
    1. Davey C, Hargreaves J, Thompson JA, et al. Analysis and reporting of stepped wedge randomised controlled trials: synthesis and critical appraisal of published studies, 2010 to 2014. Trials 2015;16:358. 10.1186/s13063-015-0838-3
    1. Hargreaves JR, Copas AJ, Beard E, et al. Five questions to consider before conducting a stepped wedge trial. Trials 2015;16:350. 10.1186/s13063-015-0841-8
    1. Prost A, Binik A, Abubakar I, et al. Logistic, ethical, and political dimensions of stepped wedge trials: critical review and case studies. Trials 2015;16:351. 10.1186/s13063-015-0837-4
    1. Grayling MJ, Wason JM, Mander AP. Stepped wedge cluster randomized controlled trial designs: a review of reporting quality and design features. Trials 2017;18:33. 10.1186/s13063-017-1783-0
    1. Taljaard M, Hemming K, Shah L, Giraudeau B, Grimshaw JM, Weijer C. Inadequacy of ethical conduct and reporting of stepped wedge cluster randomized trials: Results from a systematic review. Clin Trials 2017;14:333-41. 10.1177/1740774517703057
    1. Martin J. Advancing knowledge in stepped-wedge cluster randomised trials. University of Birmingham, UK. 2018.
    1. Hooper R, Bourke L. Cluster randomised trials with repeated cross sections: alternatives to parallel group designs. BMJ 2015;350:h2925. 10.1136/bmj.h2925
    1. Moher D, Schulz KF, Simera I, Altman DG. Guidance for developers of health research reporting guidelines. PLoS Med 2010;7:e1000217. 10.1371/journal.pmed.1000217
    1. Hemming K, Girling AJ, Haines T, Lilford R. Protocol: Consort extension to stepped wedge cluster randomised controlled trials. Equator network. .
    1. Barker D, McElduff P, D’Este C, Campbell MJ. Stepped wedge cluster randomised trials: a review of the statistical methodology used and available. BMC Med Res Methodol 2016;16:69. 10.1186/s12874-016-0176-5
    1. Hughes JP, Granston TS, Heagerty PJ. Current issues in the design and analysis of stepped wedge trials. Contemp Clin Trials 2015;45(Pt A):55-60. 10.1016/j.cct.2015.07.006
    1. Doussau A, Grady C. Deciphering assumptions about stepped wedge designs: the case of Ebola vaccine research. J Med Ethics 2016;42:797-804. 10.1136/medethics-2015-103292
    1. Eldridge SM, Chan CL, Campbell MJ, et al. PAFS consensus group CONSORT 2010 statement: extension to randomised pilot and feasibility trials. Pilot Feasibility Stud 2016;2:64. 10.1186/s40814-016-0105-8
    1. Solomon E, Rees T, Ukoumunne OC, Metcalf B, Hillsdon M. The Devon Active Villages Evaluation (DAVE) trial of a community-level physical activity intervention in rural south-west England: a stepped wedge cluster randomised controlled trial. Int J Behav Nutr Phys Act 2014;11:94. 10.1186/s12966-014-0094-z
    1. Ivers NM, Taljaard M, Dixon S, et al. Impact of CONSORT extension for cluster randomised trials on quality of reporting and study methodology: review of random sample of 300 trials, 2000-8. BMJ 2011;343:d5886. . 10.1136/bmj.d5886
    1. Hopewell S, Clarke M, Moher D, et al. CONSORT Group CONSORT for reporting randomised trials in journal and conference abstracts. Lancet 2008;371:281-3. 10.1016/S0140-6736(07)61835-2
    1. Wang M, Jin Y, Hu ZJ, et al. The reporting quality of abstracts of stepped wedge randomized trials is suboptimal: A systematic survey of the literature. Contemp Clin Trials Commun 2017;8:1-10. 10.1016/j.conctc.2017.08.009.
    1. Hospital San Juan de Dios Guatemala. Scaling Up an Integrated Approach to Improve Delivery Care in North Guatemala With Stepped Wedge Design (QVLM).
    1. Haugen AS, Søfteland E, Almeland SK, et al. Effect of the World Health Organization checklist on patient outcomes: a stepped wedge cluster randomized controlled trial. Ann Surg 2015;261:821-8. 10.1097/SLA.0000000000000716
    1. Fuller C, Michie S, Savage J, et al. The Feedback Intervention Trial (FIT)--improving hand-hygiene compliance in UK healthcare workers: a stepped wedge cluster randomised controlled trial. PLoS One 2012;7:e41617. 10.1371/journal.pone.0041617
    1. Haines TP, Hemming K. Stepped-wedge cluster-randomised trials: level of evidence, feasibility and reporting. J Physiother 2018;64:63-6. 10.1016/j.jphys.2017.11.008
    1. Kotz D, Spigt M, Arts IC, Crutzen R, Viechtbauer W. Researchers should convince policy makers to perform a classic cluster randomized controlled trial instead of a stepped wedge design when an intervention is rolled out. J Clin Epidemiol 2012;65:1255-6. 10.1016/j.jclinepi.2012.06.016
    1. Hemming K, Taljaard M. Sample size calculations for stepped wedge and cluster randomised trials: a unified approach. J Clin Epidemiol 2016;69:137-46. 10.1016/j.jclinepi.2015.08.015
    1. Lawrie J, Carlin JB, Forbes AB. Optimal stepped wedge designs. Stat Probab Lett 2015;99:210-4. 10.1016/j.spl.2015.01.024
    1. Zhan Z, de Bock GH, van den Heuvel ER. Statistical methods for unidirectional switch designs: Past, present, and future. Stat Methods Med Res 2017;962280216689280.
    1. Hemming K, Lilford R, Girling AJ. Stepped-wedge cluster randomised controlled trials: a generic framework including parallel and multiple-level designs. Stat Med 2015;34:181-96. 10.1002/sim.6325
    1. Piaggio G, Elbourne DR, Pocock SJ, Evans SJ, Altman DG, CONSORT Group Reporting of noninferiority and equivalence randomized trials: extension of the CONSORT 2010 statement. JAMA 2012;308:2594-604. 10.1001/jama.2012.87802
    1. Solomon E, Rees T, Ukoumunne OC, Hillsdon M. The Devon Active Villages Evaluation (DAVE) trial: study protocol of a stepped wedge cluster randomised trial of a community-level physical activity intervention in rural southwest England. BMC Public Health 2012;12:581. 10.1186/1471-2458-12-581
    1. McGuinness SL, O’Toole JE, Boving TB, et al. Protocol for a cluster randomised stepped wedge trial assessing the impact of a community-level hygiene intervention and a water intervention using riverbank filtration technology on diarrhoeal prevalence in India. BMJ Open 2017;7:e015036. 10.1136/bmjopen-2016-015036
    1. Reuther S, Holle D, Buscher I, et al. Effect evaluation of two types of dementia-specific case conferences in German nursing homes (FallDem) using a stepped-wedge design: study protocol for a randomized controlled trial. Trials 2014;15:319. 10.1186/1745-6215-15-319
    1. Zwarenstein M, Treweek S, Gagnier JJ, et al. CONSORT group. Pragmatic Trials in Healthcare (Practihc) group Improving the reporting of pragmatic trials: an extension of the CONSORT statement. BMJ 2008;337:a2390. 10.1136/bmj.a2390
    1. Li AH, Garg AX, Prakash V, et al. Promoting deceased organ and tissue donation registration in family physician waiting rooms (RegisterNow-1 trial): study protocol for a pragmatic, stepped-wedge, cluster randomized controlled registry. Trials 2017;18:610. 10.1186/s13063-017-2333-5
    1. Foot H, Freeman C, Hemming K, et al. Reducing Medical Admissions into Hospital through Optimising Medicines (REMAIN HOME) Study: protocol for a stepped-wedge, cluster-randomised trial. BMJ Open 2017;7:e015301. 10.1136/bmjopen-2016-015301
    1. NDiaye JL, Cissé B, Ba EH, et al. Safety of Seasonal Malaria Chemoprevention (SMC) with Sulfadoxine-Pyrimethamine plus Amodiaquine when Delivered to Children under 10 Years of Age by District Health Services in Senegal: Results from a Stepped-Wedge Cluster Randomized Trial. PLoS One 2016;11:e0162563. 10.1371/journal.pone.0162563
    1. Hoffmann TC, Glasziou PP, Boutron I, et al. Better reporting of interventions: template for intervention description and replication (TIDieR) checklist and guide. BMJ 2014;348:g1687. 10.1136/bmj.g1687
    1. Shimakawa Y, Lemoine M, Mendy M, et al. Population-based interventions to reduce the public health burden related with hepatitis B virus infection in the gambia, west Africa. Trop Med Health 2014;42(Suppl):59-64. 10.2149/tmh.2014-S08
    1. Shadish WR, Cook TD, Campbell DT. Experimental and Quasi-Experimental Designs for Generalized Causal Inference. Wadsworth Cangage Learning, 2002.
    1. Hemming K, Ryan R, Gill P, Westerby P, Jolly K, Marshall T. Targeted case finding in the prevention of cardiovascular disease: a stepped wedge cluster randomised controlled trial. Br J Gen Pract 2016;66:e758-67. 10.3399/bjgp16X686629
    1. Rutterford C, Taljaard M, Dixon S, Copas A, Eldridge S. Reporting and methodological quality of sample size calculations in cluster randomized trials could be improved: a review. J Clin Epidemiol 2015;68:716-23. 10.1016/j.jclinepi.2014.10.006
    1. Hussey MA, Hughes JP. Design and analysis of stepped wedge cluster randomized trials. Contemp Clin Trials 2007;28:182-91. 10.1016/j.cct.2006.05.007
    1. Baio G, Copas A, Ambler G, Hargreaves J, Beard E, Omar RZ. Sample size calculation for a stepped wedge trial. Trials 2015;16:354. 10.1186/s13063-015-0840-9
    1. Hemming K, Girling A. A menu driven facility for sample size for power and detectable difference calculations in stepped wedge randomised trials. Stata J 2014;14:363-80.
    1. Hayes RJ, Bennett S. Simple sample size calculation for cluster-randomized trials. Int J Epidemiol 1999;28:319-26. 10.1093/ije/28.2.319
    1. Martin J, Girling A, Nirantharakumar K, Ryan R, Marshall T, Hemming K. Intra-cluster and inter-period correlation coefficients for cross-sectional cluster randomised controlled trials for type-2 diabetes in UK primary care. Trials 2016;17:402. 10.1186/s13063-016-1532-9
    1. Cook JA, Julious SA, Sones W, et al. Choosing the target difference (‘effect size’) for a randomised controlled trial - DELTA2guidance protocol. Trials 2017;18:271. 10.1186/s13063-017-1969-5
    1. Hoenig JM, Heisey DM. The abuse of power. Am Stat 2001;55:19-24. 10.1198/000313001300339897
    1. Kristunas CA, Hemming K, Eborall HC, Gray LJ. The use of feasibility studies for stepped-wedge cluster randomised trials: protocol for a review of impact and scope. BMJ Open 2017;7:e017290. 10.1136/bmjopen-2017-017290
    1. Zou GY, Donner A, Klar N. Group sequential methods for cluster randomization trials with binary outcomes. Clin Trials 2005;2:479-87. 10.1191/1740774505cn126oa
    1. Mhurchu CN, Gorton D, Turley M, et al. Effects of a free school breakfast programme on children’s attendance, academic achievement and short-term hunger: results from a stepped-wedge, cluster randomised controlled trial. J Epidemiol Community Health 2013;67:257-64. 10.1136/jech-2012-201540
    1. Leontjevas R, Gerritsen DL, Smalbrugge M, Teerenstra S, Vernooij-Dassen MJ, Koopmans RT. A structural multidisciplinary approach to depression management in nursing-home residents: a multicentre, stepped-wedge cluster-randomised trial. Lancet 2013;381:2255-64. 10.1016/S0140-6736(13)60590-5
    1. Ni Mhurchu C, Turley M, Gorton D, et al. Effects of a free school breakfast programme on school attendance, achievement, psychosocial function, and nutrition: a stepped wedge cluster randomised trial. BMC Public Health 2010;10:738. 10.1186/1471-2458-10-738
    1. Moulton LH, Golub JE, Durovni B, et al. Statistical design of THRio: a phased implementation clinic-randomized study of a tuberculosis preventive therapy intervention. Clin Trials 2007;4:190-9. 10.1177/1740774507076937
    1. Ivers NM, Halperin IJ, Barnsley J, et al. Allocation techniques for balance at baseline in cluster randomized trials: a methodological review. Trials 2012;13:120. 10.1186/1745-6215-13-120
    1. Higgins JPT, Sterne JAC, Savović J, et al. A revised tool for assessing risk of bias in randomized trials In: Chandler J, McKenzie J, Boutron I, Welch V, ed. Cochrane Methods. Cochrane Database of Systematic Reviews; 2016:10.
    1. Caille A, Kerry S, Tavernier E, Leyrat C, Eldridge S, Giraudeau B. Timeline cluster: a graphical tool to identify risk of bias in cluster randomised trials. BMJ 2016;354:i4291. 10.1136/bmj.i4291
    1. Priestley G, Watson W, Rashidian A, et al. Introducing Critical Care Outreach: a ward-randomised trial of phased introduction in a general hospital. Intensive Care Med 2004;30:1398-404. 10.1007/s00134-004-2268-7
    1. United Nations. International Covenant on Civil and Political Rights. 1966.
    1. Council of Europe. Treaty No.164, Convention for the Protection of Human Rights and Dignity of the Human Being with regard to the Application of Biology and Medicine: Convention on Human Rights and Biomedicine (1997): Chapter V—Scientific research.
    1. Taljaard M, Weijer C, Grimshaw JM, Eccles MP, Ottawa Ethics of Cluster Randomised Trials Consensus Group The Ottawa Statement on the ethical design and conduct of cluster randomised trials: precis for researchers and research ethics committees. BMJ 2013;346:f2838. 10.1136/bmj.f2838
    1. Edwards SJ, Braunholtz DA, Lilford RJ, Stevens AJ. Ethical issues in the design and conduct of cluster randomised controlled trials. BMJ 1999;318:1407-9. 10.1136/bmj.318.7195.1407
    1. Eldridge SM, Ashby D, Feder GS. Informed patient consent to participation in cluster randomized trials: an empirical exploration of trials in primary care. Clin Trials 2005;2:91-8. 10.1191/1740774505cn070oa
    1. McCarney R, Warner J, Iliffe S, van Haselen R, Griffin M, Fisher P. The Hawthorne Effect: a randomised, controlled trial. BMC Med Res Methodol 2007;7:30. 10.1186/1471-2288-7-30
    1. Senn S. Testing for baseline balance in clinical trials. Stat Med 1994;13:1715-26. 10.1002/sim.4780131703
    1. Thompson JA, Fielding KL, Davey C, Aiken AM, Hargreaves JR, Hayes RJ. Bias and inference from misspecified mixed-effect models in stepped wedge trial analysis. Stat Med 2017;36:3670-82. 10.1002/sim.7348
    1. Taljaard M, Teerenstra S, Ivers NM, Fergusson DA. Substantial risks associated with few clusters in cluster randomized and stepped wedge designs. Clin Trials 2016;13:459-63. 10.1177/1740774516634316
    1. Eldridge SM, Ukoumunne OC, Carlin JB. The Intra‐Cluster Correlation Coefficient in Cluster Randomized Trials: A Review of Definitions. Int Stat Rev 2009;77:378-94. 10.1111/j.1751-5823.2009.00092.x
    1. Ukoumunne OC, Forbes AB, Carlin JB, Gulliford MC. Comparison of the risk difference, risk ratio and odds ratio scales for quantifying the unadjusted intervention effect in cluster randomized trials. Stat Med 2008;27:5143-55. 10.1002/sim.3359
    1. Pedroza C, Thanh Truong VT. Performance of models for estimating absolute risk difference in multicenter trials with binary outcome. BMC Med Res Methodol 2016;16:113. 10.1186/s12874-016-0217-0
    1. ICMJE International Committee of Medical Journal Editors. Recommendations for the Conduct, Reporting, Editing and Publication of Scholarly Work in Medical Journals.
    1. Azar M, Riehm KE, McKay D, Thombs BD. Transparency of Outcome Reporting and Trial Registration of Randomized Controlled Trials Published in the Journal of Consulting and Clinical Psychology. PLoS One 2015;10:e0142894. 10.1371/journal.pone.0142894
    1. Killeen S, Sourallous P, Hunter IAPF, Hartley JEMDBF, Grady HLOMDF. Registration rates, adequacy of registration, and a comparison of registered and published primary outcomes in randomized controlled trials published in surgery journals. Ann Surg 2014;259:193-6. 10.1097/SLA.0b013e318299d00b
    1. van de Wetering FT, Scholten RJPM, Haring T, Clarke M, Hooft L. Trial registration numbers are underreported in biomedical publications. PLoS One 2012;7:e49599. 10.1371/journal.pone.0049599

Source: PubMed

3
Abonner