{"id":7721,"date":"2026-09-01T10:03:26","date_gmt":"2026-09-01T08:03:26","guid":{"rendered":"https:\/\/mediconomics.com\/glossar\/win-ratio\/"},"modified":"2026-09-01T10:03:26","modified_gmt":"2026-09-01T08:03:26","slug":"win-ratio","status":"publish","type":"glossary","link":"https:\/\/mediconomics.com\/en\/glossar\/win-ratio\/","title":{"rendered":"Win Ratio"},"content":{"rendered":"<p>The win ratio is a comparison method for hierarchically ordered composite endpoints. Each patient in the treatment group is paired with patients in the control group; for each pair, the clinically most important event is compared first. If this comparison does not result in a win or loss, the next-ranked component decides. The ratio of all won comparisons to all lost comparisons yields the win ratio.   <\/p>\n<h2>Hierarchy and Pairwise Comparisons<\/h2>\n<p>The endpoint hierarchy is established before study initiation, for example death before hospitalization and hospitalization before symptom deterioration. For each group pair, it is assessed whether a difference is detectable in the highest evaluable component. If the treated patient wins, a win is counted; if the control patient wins, a loss occurs; without a decisive difference, the pair remains a tie or indeterminate.  <\/p>\n<p>The method thus uses not only the information of whether a component occurred at some point, but the clinical sequence of the components. For time-to-event components, the analysis plan must also specify how differing follow-up times and censoring within a pair are handled. An insufficiently observed pair must not be assessed as if a later event were certain not to have occurred.  <\/p>\n<h2>Composition of the Metric<\/h2>\n<p>The number of comparison pairs can be large because one patient is compared with many patients in the other group. This requires an evaluation method that accounts for the dependence of pairwise comparisons: the same patient contributes to multiple comparisons. Confidence intervals and tests must not treat this reuse as independent individual observations.  <\/p>\n<p>A win ratio greater than one indicates more wins than losses in favor of the treatment under the defined hierarchy. It does not indicate how large the benefit is in days, points, or events. Supplementary information on the individual components, tied pairs, and observation duration is necessary so that the metric does not obscure a dominant but clinically small difference.  <\/p>\n<h2>Distinction from the Classical Composite Endpoint<\/h2>\n<p>Unlike a classical composite endpoint, the win ratio does not count the components as equally ranked first events. In the classical approach, a frequent, less severe event can dominate the comparison even though a rarer severe event is clinically more important. The win ratio requires this priority to be explicitly defined and applied first in each pair.  <\/p>\n<p>A composite endpoint does not yet exist as a separate entry in the glossary. The win ratio cannot arbitrarily &#8220;weight&#8221; it retrospectively: the hierarchy, event definitions, and rules for tied pairs must be established before data review. The selection of components also follows a clinical question and not solely the desire for more observed events.  <\/p>\n<p>The method is particularly sensitive to imprecisely defined event windows. If, for example, a hospitalization is identified only after varying follow-up durations, a pair may be incorrectly classified as decided or tied. Data collection and calculation must therefore use the same temporal requirements.  <\/p>\n<h2>Relevance for clinical trials<\/h2>\n<p>Planning requires a clinically agreed ranking, uniform collection rules for all components, and data with which pairwise comparisons can be formed with temporal accuracy. In mortality- or progression-related studies, missing event times and unequal follow-up directly affect the comparability of pairs. The study report should make visible which component actually decided the wins and losses.  <\/p>\n<p>Full-service CROs such as Mediconomics support the translation of a clinical priority order into endpoint definitions, the specification of pairing and censoring rules in the analysis plan, and the creation of transparent result presentations. Biostatistics and data management can verify whether timestamps, event coding, and follow-up status permit hierarchical evaluation without hidden classification gaps. <\/p>\n<p>Result verification should be able to trace exemplary pair decisions back to the underlying event data. This allows verification of whether the prioritized component was applied correctly and whether censoring actually had to produce a tied pair rather than a win or loss. <\/p>\n<p>This traceability is essential for the evaluation, particularly with multiple temporally overlapping clinical event components.<\/p>\n<h2>Frequently Asked Questions (FAQ)<\/h2>\n<p><strong>Does a win ratio of one mean that all patients perform equally?<\/strong><\/p>\n<p>No. It means that wins and losses balance out across the defined pairwise comparisons. There can still be many different individual courses and numerous tied pairs.  <\/p>\n<p><strong>Can the order of components be changed after the results?<\/strong><\/p>\n<p>No. Retrospective prioritization would adapt the statement of the metric to the observed data. The medical ranking, including the rules for ties, belongs in the protocol or analysis plan before the start of the evaluation.  <\/p>\n<p><strong>Does the win ratio replace a presentation of the individual components?<\/strong><\/p>\n<p>No. The metric condenses the hierarchical decision. Individual event rates, time courses, and safety data remain necessary to assess the contribution of each component to the overall finding and possible conflicting objectives.  <\/p>\n<h2>Regulatory References<\/h2>\n<ul>\n<li>ICH E9(R1), Addendum on Estimands and Sensitivity Analyses \u2013 requires precise definition of variables and summary.<\/li>\n<li>EMA\/CHMP\/205\/95 Rev.6, Guideline on the Clinical Evaluation of Anticancer Medicinal Products \u2013 addresses clinically relevant efficacy endpoints in oncology.<\/li>\n<li>EMA\/CHMP\/27994\/2008\/Rev.1, Appendix 1 on PFS and DFS \u2013 specifies event definition and collection issues for time-to-event endpoints.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>The win ratio is a comparison method for hierarchically ordered composite endpoints. Each patient in the treatment group is paired with patients in the control group; for each pair, the clinically most important event is compared first. If this comparison does not result in a win or loss, the next-ranked component decides. The ratio of [&hellip;]<\/p>\n","protected":false},"author":10,"featured_media":0,"parent":0,"template":"","meta":{"_acf_changed":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"glossary-cat":[22],"class_list":["post-7721","glossary","type-glossary","status-publish","hentry","glossary-cat-biostatistik-methodik"],"acf":[],"related_terms":"","external_url":"","internal_reference_id":"","_links":{"self":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary\/7721","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary"}],"about":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/types\/glossary"}],"author":[{"embeddable":true,"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/users\/10"}],"version-history":[{"count":0,"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary\/7721\/revisions"}],"wp:attachment":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/media?parent=7721"}],"wp:term":[{"taxonomy":"glossary-cat","embeddable":true,"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary-cat?post=7721"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}