ArticleTrials2017
Understanding the cluster randomised crossover design: a graphical illustraton of the components of variation and a sample size tutorial.
Article in Trials, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT05221866 (Efficiency And Quality In Post-Surgical Pain Therapy After Discharge), which is not on this map. Cited by 47 papers, 2 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Efficiency And Quality In Post-Surgical Pain Therapy After Discharge
Who cites it
47 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Extending the I-squared statistic to describe treatment effect heterogeneity in cluster, multi-centre randomized trials and individual patient data meta-analysis.Statistical methods in medical research · 2021Pooled it
- Design, implementation, and analysis considerations for cluster-randomized trials in infection control and hospital epidemiology: A systematic review.Infection control and hospital epidemiology · 2019Pooled it
- Cluster-Randomised Controlled Trial of At-Home Virtual Reality for People With Chronic Musculoskeletal Pain on the Waiting List.European journal of pain (London, England) · 2025Trial
- Ticagrelor Compared to Clopidogrel in Acute Coronary Syndromes trial (TC4): a Bayesian pragmatic cluster randomized controlled trial.CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne · 2025Trial
- Effectiveness, Safety, and Acceptability of Primaquine Mass Drug Administration in Low-Endemicity Areas in Southern Thailand: Proof-of-Concept Study.JMIR public health and surveillance · 2024Trial
- Effects of Cognitive Orientation to Daily Occupational Performance and Conductive Education Treatment Approaches on Fine Motor Skills, Activity and Participation Limitations in Children with Down Syndrome: A Randomised Controlled Trial.Journal of autism and developmental disorders · 2024Trial
- Using a Video Game Intervention to Increase Hospitalists' Advance Care Planning Conversations with Older Adults: a Stepped Wedge Randomized Clinical Trial.Journal of general internal medicine · 2023Trial
- Rethinking children's physical activity interventions at school: A new context-specific approach.Frontiers in public health · 2023Trial
- Promoting patient and nurse safety: testing a behavioural health intervention in a learning healthcare system: results of the DEMEANOR pragmatic, cluster, cross-over trial.BMJ open quality · 2022Trial
- Provision of the progestogen-only pill by community pharmacies as bridging contraception for women receiving emergency contraception: the Bridge-it RCT.Health technology assessment (Winchester, England) · 2021Trial
- Trial
- Use of effective contraception following provision of the progestogen-only pill for women presenting to community pharmacies for emergency contraception (Bridge-It): a pragmatic cluster-randomised crossover trial.Lancet (London, England) · 2020Trial
- What is estimated in cluster randomized crossover trials with informative sizes? A survey of estimands and common estimators.Statistical methods in medical research · 2026Article
- Additional crossovers in cluster randomised crossover trials do not always increase statistical power.Clinical trials (London, England) · 2026Article
- Optimal Designs in Open-Cohort Longitudinal Cluster Randomized Trials With a Continuous Outcome.Biometrical journal. Biometrische Zeitschrift · 2026Article
- Sample Size Determination for Comparing Slopes in Cluster Randomized Trials With Longitudinal Measurements.Statistics in medicine · 2026Article
- Fracture table vs. lateral positioning for intramedullary fixation of femur fractures (The FLiP Trial): the feasibility of a cluster randomized crossover trial.Pilot and feasibility studies · 2026Article
- Advancing movement and physical literacy earlier (AMPLE) program for promoting physical literacy and executive function among young children: study protocol of a cluster randomized crossover trial.BMC public health · 2025Article
- Article
- Design of a cluster-randomized, hybrid type 1 effectiveness-implementation trial of a care navigation intervention to increase substance use disorder treatment engagement: study protocol.Addiction science & clinical practice · 2025Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundIn a cluster randomised crossover (CRXO) design, a sequence of interventions is assigned to a group, or 'cluster' of individuals. Each cluster receives each intervention in a separate period of time, forming 'cluster-periods'. Sample size calculations for CRXO trials need to account for both the cluster randomisation and crossover aspects of the design. Formulae are available for the two-period, two-intervention, cross-sectional CRXO design, however implementation of these formulae is known to be suboptimal. The aims of this tutorial are to illustrate the intuition behind the design; and provide guidance on performing sample size calculations.
methodsGraphical illustrations are used to describe the effect of the cluster randomisation and crossover aspects of the design on the correlation between individual responses in a CRXO trial. Sample size calculations for binary and continuous outcomes are illustrated using parameters estimated from the Australia and New Zealand Intensive Care Society - Adult Patient Database (ANZICS-APD) for patient mortality and length(s) of stay (LOS).
resultsThe similarity between individual responses in a CRXO trial can be understood in terms of three components of variation: variation in cluster mean response; variation in the cluster-period mean response; and variation between individual responses within a cluster-period; or equivalently in terms of the correlation between individual responses in the same cluster-period (within-cluster within-period correlation, WPC), and between individual responses in the same cluster, but in different periods (within-cluster between-period correlation, BPC). The BPC lies between zero and the WPC. When the WPC and BPC are equal the precision gained by crossover aspect of the CRXO design equals the precision lost by cluster randomisation. When the BPC is zero there is no advantage in a CRXO over a parallel-group cluster randomised trial. Sample size calculations illustrate that small changes in the specification of the WPC or BPC can increase the required number of clusters.
conclusionsBy illustrating how the parameters required for sample size calculations arise from the CRXO design and by providing guidance on both how to choose values for the parameters and perform the sample size calculations, the implementation of the sample size formulae for CRXO trials may improve.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.