Data_Sheet_1_Application of the Composite Quality Score (CQS-2B) versus Cochrane’s Risk of Bias tool (Version 2) in systematic reviews of clinical trials – an exploratory study.PDF

ObjectivesTo explore whether systematic review conclusions generated from Cochrane’s second version of its Risk of Bias tool (RoB 2) for trial appraisal differ when the Composite Quality Score, Version 2.B (CQS-2B) is used instead and to develop a testable hypothesis based on these findings.
MethodsPubMed was searched for one single systematic review. From the review’s accepted trials, data concerning effect estimates and overall bias risk according to the RoB 2 tool were extracted. All trial reports were appraised again using the CQS-2B. Datasets were stratified according to overall bias risk (RoB 2) or corroboration (C-) level (CQS-2B). The effect estimates from trials with ‘low bias risk’ (RoB 2) and with highest C-level (CQS-2B) were pooled separately. These pooled effect estimates were statistically and all clinical conclusions qualitatively compared.
ResultsThe pooled effect estimates for trials with ‘low bias risk’ (RoB 2) were −0.07, 95% CI: −0.10 to −0.04 (I2 = 0.0%) and for the highest C-levels (CQS-2B) 0.08, 95% CI: −0.12 to −0.04 (I2 = 57.0%). The difference was statistically not significant (p = 0.70). Contrary to the RoB 2 tool, no clinical conclusions in line with the CQS-2B were made, because the effect estimates were judged to be erroneously overestimated, due to high risk of bias.
ConclusionA testable hypothesis was generated suggesting that trial appraisal using the CQS-2B may provide more conservative conclusions based on similar data than with the RoB 2 tool.

研究目的：探讨当使用综合质量评分2.B版（Composite Quality Score, Version 2.B, CQS-2B）替代考克兰（Cochrane）偏倚风险评估工具第二版（Risk of Bias 2, RoB 2）进行试验评价时，系统评价结论是否存在差异，并基于研究结果生成可检验的假说。
研究方法：以PubMed数据库检索单篇系统评价。从该评价纳入的试验中，提取基于偏倚风险评估工具第二版（RoB 2）所得的效应量估计值及总体偏倚风险相关数据。采用综合质量评分2.B版（CQS-2B）对所有试验报告重新进行评价。根据偏倚风险评估工具第二版的总体偏倚风险等级，或综合质量评分2.B版的佐证（corroboration）等级（C-）对数据集进行分层。分别合并低偏倚风险（RoB 2）试验与最高佐证等级（CQS-2B）试验的效应量估计值，对合并后的效应量估计值进行统计学比较，并对所有临床结论进行定性比较。
研究结果：低偏倚风险（RoB 2）试验的合并效应量估计值为-0.07，95%置信区间（Confidence Interval, CI）为-0.10至-0.04（I²=0.0%）；最高佐证等级（CQS-2B）试验的合并效应量估计值为0.08，95%置信区间为-0.12至-0.04（I²=57.0%）。两组差异无统计学意义（p=0.70）。与偏倚风险评估工具第二版（RoB 2）所得结论不同，基于综合质量评分2.B版（CQS-2B）未得出相符的临床结论，原因是效应量估计值因较高的偏倚风险被错误高估。
研究结论：本研究生成了可检验的假说，即基于相似数据，使用综合质量评分2.B版（CQS-2B）进行试验评价所得结论，较偏倚风险评估工具第二版（RoB 2）更为保守。