没有考虑的集群假设仍然在牙科研究中的集群随机试验中的推理受到损害
Samer Mheissen1, Haris Khan2, Mays Aldandan3
1Private Practice, Damascus, Syria.
Korean journal of orthodontics
|November 25, 2024
概括
在正义牙科集群随机试验 (CRT) 中,样本大小计算往往是不充分的. 大多数研究没有适当考虑集群设计,需要平均50%的样本大小增加才能获得足够的统计能力.
科学领域:
- 牙科研究 牙科研究
- 临床试验方法论 临床试验方法论
- 生物统计学 生物统计学
背景情况:
- ортодонтика研究经常使用集群随机试验 (CRT) 来解释小组级干预.
- 准确的样本大小计算对于临床试验的有效性和功率至关重要.
- 之前对CRT样本大小方法的评估已经突出了潜在的缺陷.
研究的目的:
- 评估正义牙科集群随机试验 (CRT) 中样本大小计算的适当性.
- 为了确定在这个特定的研究领域是否使用了最佳的统计方法来确定样本大小.
- 为了识别正义牙科CRT中样本大小报告和计算中常见的遗漏.
主要方法:
- 用一种超流行病学方法来分析已发表的正统牙科CRT.
- 这些研究是从2017年至2023年间的顶尖牙科期刊中挑选出来的.
- 提取了关键特征和样本大小变量;计算了设计效应,并根据指定的集群内相关系数 (0.1) 重计算了样本大小.
主要成果:
- 纳入了105个正义牙科CRT,其中100个报告了样本大小计算.
- 9%的试验遗漏了对样本大小计算的基本效果测量.
- 仅报告了一项试验并进行了设计效应调整;重新计算表明需要平均增加50%的样本大小.
结论:
- 在正牙科CRT中样本大小的计算往往是低于最佳的.
- 需要提高对集群设计原则的认识和正确应用,以确定样本大小.
- 改进样本大小计算将有助于缓解正学研究不足的问题.
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