{"doi":"10.1080/10543406.2014.901341","title":"Flexible Stopping Boundaries When Changing Primary Endpoints After Unblinded Interim Analyses","abstract":null,"journal":"Journal of Biopharmaceutical Statistics","year":2014,"id":644870,"datarank":0.40620753016533157,"base_score":2.70805020110221,"endowment":2.70805020110221,"self_citation_contribution":0.40620753016533157,"citation_network_contribution":0.0,"self_endowment_contribution":0.40620753016533157,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":14,"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":390426,"name":"Joseph G. Ibrahim","orcid":"0000-0003-2428-6552","position":1,"is_corresponding":false},{"id":49892,"name":"Haitao Chu","orcid":"0000-0003-0932-598X","position":2,"is_corresponding":false},{"id":1678753,"name":"Liddy M. Chen","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Flexible Stopping Boundaries When Changing Primary Endpoints After Unblinded Interim Analyses","abstract":"It has been widely recognized that interim analyses of accumulating data in a clinical trial can inflate type I error. Different methods, from group sequential boundaries to flexible alpha spending functions, have been developed to control the overall type I error at prespecified level. These methods mainly apply to testing the same endpoint in multiple interim analyses. In this article, we consider a group sequential design with preplanned endpoint switching after unblinded interim analyses. We extend the alpha spending function method to group sequential stopping boundaries when the parameters can be different between interim, or between interim and final analyses.","is_dataset_classified":null,"base_score":0.0,"endowment":0.0,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"24697500","pmcid":"PMC4024106","openalex_id":"https://openalex.org/W24697500","authors":[],"funders":[{"funder_name":"NCI NIH HHS","grant_id":"2P30CA077598","title":null},{"funder_name":"NIEHS NIH HHS","grant_id":"P01 ES014635","title":null},{"funder_name":"NCI NIH HHS","grant_id":"1P01CA142538","title":null},{"funder_name":"NCI NIH HHS","grant_id":"P01 CA142538","title":null},{"funder_name":"NIMHD NIH HHS","grant_id":"U54-MD008620","title":null}],"total_grants":5,"fwci":0.0,"citation_percentile":0.00165766,"influential_citations":0,"citation_trend":[],"oa_status":"closed","license":null,"oa_locations":[{"url":"http://ci.nii.ac.jp/naid/40019674666","host_type":"journal"},{"url":"https://www.tandfonline.com/doi/pdf/10.1080/10543406.2014.901341","host_type":"publisher"}],"fields_of_study":["Statistical Methods in Clinical Trials","Advanced Causal Inference Techniques","Statistical Methods and Bayesian Inference"],"mesh_terms":["Humans","Endpoint Determination","Research Design","Clinical Trials as Topic"],"keywords":["Computer science","Business","Interim Analyses","Alpha Spending Function","Group Sequential Trials","Stopping Boundaries","Switching Endpoints"],"sdg_mappings":[],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-09T02:18:34.214722Z","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":[]}