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ランダム化試験におけるサンプルサイズの滑り込み:排除と失われたもの
Kenneth F Schulz1, David A Grimes
1Family Health International, PO Box 13950, Research Triangle Park, NC 27709, USA. KSchulz@fhi.org
Lancet (London, England)
|March 13, 2002
まとめ
適切な臨床試験分析には,すべてのランダム化参加者を含む必要があります. 善意をもってしても,誤った排除は,研究の妥当性と一般化性を損なう可能性があります.
科学分野:
- クリニック・トライアル 臨床試験
- バイオ統計学 バイオ統計学
- 研究方法論 研究方法論
背景:
- ランダム化は,臨床試験における公平な治療比較に不可欠である.
- 参加者の遵守と保持は,試験の完全性に影響を与える重要な課題です.
- ランダム化後の排除は,結果の妥当性を損なう可能性があります.
研究 の 目的:
- 主要分析にランダムに選ばれたすべての参加者を含めることの重要性を強調する.
- ランダム化後に参加者を除外することによってもたらされる潜在的なバイアスを強調する.
- 参加者の保持とデータ分析のベストプラクティスに関する研究者を指導する.
主な方法:
- 主要なアウトカムに対する治療意図 (ITT) 分析の原則について議論します.
- 適格性基準とランダム化後の排除の影響について説明します.
- 参加者の留保と透明な報告を最大化するための戦略を推奨します.
主要な成果:
- ランダム化後に参加者を排除することは,理由に関係なく,バイアスを導入することができます.
- 治療意図分析は,ランダム化による利点を維持するために,プライマリ分析の黄金基準です.
- 2次分析 (プロトコルごとに,as-treated) は,ランダム化されていない比較として明確に識別されるべきである.
結論:
- すべてのランダム化参加者をプライマリ分析に含めることを厳格に遵守することは,有効な臨床試験結果のために不可欠です.
- 参加者の留保と透明な報告を最大限に高めるための積極的な措置が不可欠です.
- 誤った取り扱いによる排除は,試験の有効性を損なう重大な方法論的課題をもたらします.
関連する概念動画
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Knowledge of the sample size is the first requirement to conduct random sampling or an experiment. The sample size is the total number of units, observations, or groups (in some cases) used to get the data to estimate a population parameter. As the name suggests, the sample size is that of the sample drawn from the population and differs from the population size.
The sample size for the given experiment or sampling effort is fundamental to any study design. Sample size decides the number of...
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Random Error
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Effective sample preparation is crucial for accurate and reliable laboratory analysis. During this process, two significant sources of error can arise: concentration bias from improper sample splitting and contamination caused by methods used to reduce particle size, such as grinding or homogenization. Identifying and minimizing these potential errors is crucial to ensuring the validity of the analysis.
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