ランダム化試験におけるアウトカムの選択的な報告のための経験的証拠:プロトコルと出版された論文の比較
An-Wen Chan1, Asbjørn Hróbjartsson, Mette T Haahr
1Centre for Statistics in Medicine, Institute of Health Sciences, Headington, Oxford, England. anwen.chan@utoronto.ca
JAMA
|May 27, 2004
まとめ
ランダム化試験における選択的結果報告は一般的であり,有意な結果は完全に報告される可能性が高い. このバイアスは,公表された研究を信頼できないものにして,試験の登録と透明性のための公共プロトコルが必要になります.
科学分野:
- 臨床研究の方法論 臨床研究の方法論
- バイオ統計学 バイオ統計学
- 根拠に基づいた医学は,エビデンスに基づいた医療です.
背景:
- 選択的結果報告のバイアスが疑われるが,ケースレポートを超えた強力な経験的証拠がない.
- ランダム化試験におけるこのバイアスの程度と性質に関するデータは限られている.
研究 の 目的:
- ランダム化試験のコホートにおける結果報告バイアスの有病率と特徴を実証的に調査する.
- 報告された結果と報告されていない結果の差異と,統計的有意性との関係性を評価する.
主な方法:
- コホート研究では,102件のランダム化試験 (1994年~1995年) を分析し,プロトコルと公表された報告書を比較し,試験参加者を調査した.
- 出版物でメタアナリシスに必要なデータが不十分である場合には,アウトカムが不完全と分類された.
- 確率比は,統計的有意性およびプライマリアウトカム報告の一貫性に関連するバイアスを定量化するために計算されました.
主要な成果:
- 50%の有効性と65%の有害性の結果は,試験全体で不完全に報告されました.
- 統計的に有意なアウトカムが非有意なアウトカムよりも完全に報告される可能性が著しく高かった (ORsは有効性に対して2.4,有害性に対して4.7).
- 62%の試験では,プロトコルと出版物間の主要なアウトカムにおける不一致が示され,多くの試験参加者は報告されていないアウトカムを否定しました.
結論:
- ランダム化試験における結果報告は,しばしば不完全であり,偏っており,初期プロトコルと矛盾しています.
- 公開された研究は,この報告バイアスのために,介入の利点を過大評価することがあります.
- 治験の登録とプロトコルの公開は,透明性と信頼性を高めるために不可欠です.
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