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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">vedomostiregmed</journal-id><journal-title-group><journal-title xml:lang="ru">Регуляторные исследования и экспертиза лекарственных средств</journal-title><trans-title-group xml:lang="en"><trans-title>Regulatory Research and Medicine Evaluation</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">3034-3062</issn><issn pub-type="epub">3034-3453</issn><publisher><publisher-name>Federal State Budgetary Institution ‘Scientific Centre for Expert Evaluation of Medicinal Products’ of the Ministry of Health of the Russian Federation (FSBI ‘SCEEMP’)</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.30895/1991-2919-2025-15-1-92-104</article-id><article-id custom-type="elpub" pub-id-type="custom">vedomostiregmed-705</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>КЛИНИЧЕСКИЕ ИССЛЕДОВАНИЯ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>CLINICAL STUDIES</subject></subj-group></article-categories><title-group><article-title>Основные принципы расчета необходимой численности участников клинических исследований. Часть 2. Анализ выживаемости (обзор)</article-title><trans-title-group xml:lang="en"><trans-title>Basic Principles for Calculating the Required Number of Participants in Clinical Trials. Part 2. Survival Analysis (Review)</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-7926-6033</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Шредер</surname><given-names>О. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Shreder</surname><given-names>O. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Шредер Ольга Васильевна, канд. биол. наук</p><p>Петровский б-р, д. 8, стр. 2, Москва, 127051</p></bio><bio xml:lang="en"><p>Olga V. Shreder, Cand. Sci. (Biol.)</p><p>8/2 Petrovsky Blvd, Moscow 127051</p></bio><email xlink:type="simple">olga_shreder@list.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-8583-2372</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Горячев</surname><given-names>Д. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Goryachev</surname><given-names>D. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Горячев Дмитрий Владимирович, д-р мед. наук</p><p>Петровский б-р, д. 8, стр. 2, Москва, 127051</p></bio><bio xml:lang="en"><p>Dmitriy V. Goryachev, Dr. Sci. (Med.)</p><p>8/2 Petrovsky Blvd, Moscow 127051</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-4891-973X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Меркулов</surname><given-names>В. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Merkulov</surname><given-names>V. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Меркулов Вадим Анатольевич, д-р мед. наук, проф.</p><p>Петровский б-р, д. 8, стр. 2, Москва, 127051</p></bio><bio xml:lang="en"><p>Vadim A. Merkulov, Dr. Sci. (Med.), Professor</p><p>8/2 Petrovsky Blvd, Moscow 127051</p></bio><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Федеральное государственное бюджетное учреждение &#13;
«Научный центр экспертизы средств медицинского применения» &#13;
Министерства здравоохранения Российской Федерации</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Scientific Centre for Expert Evaluation of Medicinal Products</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2025</year></pub-date><pub-date pub-type="epub"><day>21</day><month>01</month><year>2025</year></pub-date><volume>15</volume><issue>1</issue><fpage>92</fpage><lpage>104</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Шредер О.В., Горячев Д.В., Меркулов В.А., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Шредер О.В., Горячев Д.В., Меркулов В.А.</copyright-holder><copyright-holder xml:lang="en">Shreder O.V., Goryachev D.V., Merkulov V.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.vedomostincesmp.ru/jour/article/view/705">https://www.vedomostincesmp.ru/jour/article/view/705</self-uri><abstract><sec><title>ВВЕДЕНИЕ</title><p>ВВЕДЕНИЕ. Анализ выживаемости — метод биостатистики, используемый в клинических исследованиях для подтверждения эффективности и безопасности применения лекарственных средств в долгосрочной перспективе. Актуальность метода определяется оценкой возможности экстраполяции заключения о полезности медицинского вмешательства, установленного в краткосрочном клиническом исследовании, на долгосрочный период наблюдения, а также возможности коррекции режимов дозирования и схем лечения. В настоящее время отсутствуют подробные методические рекомендации по проведению исследований по анализу выживаемости.</p></sec><sec><title>ЦЕЛЬ</title><p>ЦЕЛЬ. Систематизация технических требований к планированию дизайна событийного исследования в части определения размера выборки.</p></sec><sec><title>ОБСУЖДЕНИЕ</title><p>ОБСУЖДЕНИЕ. Обсуждены методы расчета необходимой численности субъектов для анализа выживаемости в рамках событийных исследований, в которых сбор и оценка исходов проводится в условиях цензурирования наблюдений. Описаны вероятностные модели, построенные на основе байесовской теории вероятностей, для оценки параметров выживаемости, характеризующих время и риск наступления события, а также кумулятивную долю выживших, как основных переменных для определения размера выборки участников исследования. Рассмотрены теоретические основы анализа событийного риска в дизайнах исследования выживаемости. Представлено описание гипотез, статистических моделей расчета размера выборки субъектов, определения пороговых значений параметров выживаемости в групповых последовательных дизайнах исследования событийного риска.</p></sec><sec><title>ВЫВОДЫ</title><p>ВЫВОДЫ. Представленные статистические модели могут использоваться при разработке дизайнов исследований, направленных на оценку продолжительности времени до момента наступления ожидаемого события и кумулятивного риска во время лечения и после применения лекарственных средств.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>INTRODUCTION</title><p>INTRODUCTION. Survival analysis is an important biostatistics method used in clinical trials to confirm the long-term efficacy and safety of medicinal products. The significance of this method lies in the possibility to extrapolate the conclusion regarding the benefits of a medical intervention drawn from a short-term clinical trial to a longer period and adjust dosages and treatment regimens accordingly. However, comprehensive methodological recommendations for planning survival analyses are currently lacking.</p></sec><sec><title>AIM</title><p>AIM. This study aimed to systematise the requirements for sample size calculation in event-based study designs.</p></sec><sec><title>DISCUSSION</title><p>DISCUSSION. This article presents methods for calculating the number of subjects required for survival analysis in event-driven studies with outcome collection and estimation under censoring conditions. The authors discuss Bayesian probabilistic models for estimating survival parameters, such as the time to an event, the risk of an event, and the cumulative survival rate, as key variables for determining the sample size for a study. The article presents a theoretical framework for event risk analysis in survival study designs. The authors describe hypotheses and sta­tistical models for calculating sample sizes and determining survival parameter thresholds in group sequential designs for event risk studies.</p></sec><sec><title>CONCLUSIONS</title><p>CONCLUSIONS. The statistical models presented can be used to design studies aimed at estimating the time to an expected event and the cumulative risk during treatment and following medicinal product administration.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>выборка</kwd><kwd>клинические исследования</kwd><kwd>байесовская теория вероятностей</kwd><kwd>размер выборки</kwd><kwd>вероятностные модели</kwd><kwd>выживаемость</kwd><kwd>оценка</kwd><kwd>событийные исследования</kwd><kwd>долгосрочные исследования</kwd><kwd>краткосрочные исследования</kwd></kwd-group><kwd-group xml:lang="en"><kwd>sample</kwd><kwd>clinical trials</kwd><kwd>Bayesian probability theory</kwd><kwd>sample size</kwd><kwd>probability models</kwd><kwd>survival</kwd><kwd>estimation</kwd><kwd>event-based studies</kwd><kwd>long-term studies</kwd><kwd>short-term studies</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Работа выполнена в рамках государственного задания ФГБУ «НЦЭСМП» Минздрава России № 056-00001-25-00 на проведение прикладных научных исследований (номер государственного учета НИР 124022300127-0).</funding-statement><funding-statement xml:lang="en">This study was conducted by the Scientific Centre for Expert Evaluation of Medicinal Products as part of the applied research funded under State Assignment No. 056-00001-25-00 (R&amp;D Registry No. 124022300127-0).</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Шредер ОВ, Горячев ДВ, Меркулов ВА. 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