{"doi":"10.1177/09622802231202364","title":"The staircase cluster randomised trial design: A pragmatic alternative to the stepped wedge","abstract":"<jats:p> This article introduces the ‘staircase’ design, derived from the zigzag pattern of steps along the diagonal of a stepped wedge design schematic where clusters switch from control to intervention conditions. Unlike a complete stepped wedge design where all participating clusters must collect and provide data for the entire trial duration, clusters in a staircase design are only required to be involved and collect data for a limited number of pre- and post-switch periods. This could alleviate some of the burden on participating clusters, encouraging involvement in the trial and reducing the likelihood of attrition. Staircase designs are already being implemented, although in the absence of a dedicated methodology, approaches to sample size and power calculations have been inconsistent. We provide expressions for the variance of the treatment effect estimator when a linear mixed model for an outcome is assumed for the analysis of staircase designs in order to enable appropriate sample size and power calculations. These include explicit variance expressions for basic staircase designs with one pre- and one post-switch measurement period. We show how the variance of the treatment effect estimator is related to key design parameters and demonstrate power calculations for examples based on a real trial. </jats:p>","journal":"Statistical Methods in Medical Research","year":2024,"id":643687,"datarank":0.49983067652628066,"base_score":3.332204510175204,"endowment":3.332204510175204,"self_citation_contribution":0.49983067652628066,"citation_network_contribution":0.0,"self_endowment_contribution":0.49983067652628066,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":27,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1674916,"name":"Andrew B Forbes","orcid":null,"position":1,"is_corresponding":false},{"id":471118,"name":"Richard Hooper","orcid":"0000-0002-1063-0917","position":2,"is_corresponding":false},{"id":675022,"name":"Jessica Kasza","orcid":"0000-0002-8940-0136","position":3,"is_corresponding":false},{"id":675016,"name":"Kelsey L. 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Staircase designs are already being implemented, although in the absence of a dedicated methodology, approaches to sample size and power calculations have been inconsistent. We provide expressions for the variance of the treatment effect estimator when a linear mixed model for an outcome is assumed for the analysis of staircase designs in order to enable appropriate sample size and power calculations. These include explicit variance expressions for basic staircase designs with one pre- and one post-switch measurement period. We show how the variance of the treatment effect estimator is related to key design parameters and demonstrate power calculations for examples based on a real trial. </jats:p>","is_dataset_classified":null,"base_score":3.332204510175204,"endowment":3.332204510175204,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"38031417","pmcid":"PMC10863363","openalex_id":"https://openalex.org/W4389180805","authors":[],"funders":[{"funder_name":"Australian Research Council","grant_id":"Discovery Project DP210101398","title":null},{"funder_name":"THIS Institute","grant_id":"SF-2018-01-005","title":null},{"funder_name":"Australian Research Council (ARC)","grant_id":"DP210101398","title":"Discovery Projects - Grant ID: DP210101398"}],"total_grants":3,"fwci":10.4738,"citation_percentile":0.98609656,"influential_citations":0,"citation_trend":[{"year":2024,"count":4},{"year":2025,"count":15},{"year":2026,"count":8}],"oa_status":"hybrid","license":"cc-by","oa_locations":[{"url":"https://doi.org/10.1177/09622802231202364","host_type":"journal"},{"url":"https://doi.org/10.1177/09622802231202364","host_type":"publisher"},{"url":"https://journals.sagepub.com/doi/pdf/10.1177/09622802231202364","host_type":"publisher"},{"url":"https://journals.sagepub.com/doi/full-xml/10.1177/09622802231202364","host_type":"publisher"},{"url":"https://pubmed.ncbi.nlm.nih.gov/38031417","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/10863363","host_type":"repository"},{"url":"https://qmro.qmul.ac.uk/xmlui/handle/123456789/92675","host_type":"repository"},{"url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC10863363/pdf/10.1177_09622802231202364.pdf","host_type":"repository"},{"url":"https://europepmc.org/articles/PMC10863363","host_type":"Europe_PMC"},{"url":"https://europepmc.org/articles/PMC10863363?pdf=render","host_type":"Europe_PMC"},{"url":"http://dx.doi.org/10.1177/09622802231202364","host_type":""},{"url":"https://doi.org/https://doi.org/10.1177/09622802231202364","host_type":""}],"fields_of_study":["Health Policy Implementation Science","Meta-analysis and systematic reviews","Primary Care and Health Outcomes","01 natural sciences","0101 mathematics"],"mesh_terms":["Probability","Research Design","Cluster Analysis","Linear Models","Randomized Controlled Trials as Topic","Sample Size"],"keywords":["Cluster randomised controlled trial","Wedge (geometry)","Cluster (spacecraft)","Medicine","Computer science","Mathematics","Randomized controlled trial","Internal medicine","Geometry","Sample size","Clinical Trial Design","Intracluster Correlation","Cluster Randomised Trial","Incomplete Design","Research Design","Original Research Articles","Linear Models","Cluster Analysis","Probability","Randomized Controlled Trials as Topic"],"sdg_mappings":[],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-08T18:22:48.896524Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}