Department of Dermatology, Northwestern University Feinberg School of Medicine, Suite 1600, 676 N. St Clair St, Chicago, IL, 60611, U.S.A.
Department of Preventive Medicine and Medical Social Sciences, Northwestern University Feinberg School of Medicine, Suite 1600, 676 N. St Clair St, Chicago, IL, 60611, U.S.A.
Br J Dermatol. 2015 Jul;173(1):172-83. doi: 10.1111/bjd.13907. Epub 2015 Jun 21.
The validity of randomized controlled trials (RCTs) is determined by several statistical factors.
To determine the level of recent statistical reporting in RCTs from the dermatology literature.
We searched MEDLINE for all RCTs published between 1 May 2013 and 1 May 2014 in 44 dermatology journals.
Two hundred and ten articles were screened, of which 181 RCTs from 27 journals were reviewed. Primary study outcomes were met in 122 (67.4%) studies. Sample size calculations and beta values were reported in 52 (28.7%) and 48 (26.5%) studies, respectively, and nonsignificant findings were supported in only 31 (17.1%). Alpha values were reported in 131 (72.4%) of studies with 45 (24.9%) having two-sided P-values, although adjustment for multiple statistical tests was performed in only 16 (9.9% of studies with ≥ two statistical tests performed). Sample size calculations were performed based on a single outcome in 44 (86.3%) and multiple outcomes in six (11.8%) studies. However, among studies that were powered for a single primary outcome, 20 (45.5%) made conclusions based on multiple primary outcomes. Twenty-one (41.2%) studies relied on secondary/unspecified outcomes. There were no differences for primary outcome being met (Chi-square, P = 0.29), sample size calculations (P ≥ 0.55), beta values (P = 0.89), alpha values (P = 0.65), correction for multiple statistical testing (P = 0.59), two-sided alpha (P = 0.64), support of nonsignificant findings (Fisher's exact, P = 0.23) based on the journal's impact factor.
Levels of statistical reporting are low in RCTs from the dermatology literature. Future work is needed to improve these levels of reporting.
随机对照试验（RCT）的有效性取决于几个统计因素。
确定皮肤科文献中最近 RCT 统计报告的水平。
我们在 MEDLINE 上搜索了 2013 年 5 月 1 日至 2014 年 5 月 1 日期间在 44 种皮肤科期刊上发表的所有 RCT。
筛选出 210 篇文章，其中 27 种期刊的 181 项 RCT 进行了回顾。122 项（67.4%）研究达到了主要研究终点。52 项（28.7%）和 48 项（26.5%）研究分别报告了样本量计算和β值，仅 31 项（17.1%）支持无显著发现。131 项（72.4%）研究报告了α值，其中 45 项（24.9%）有双侧 P 值，尽管只有 16 项（进行了≥2 项统计学检验的研究中的 9.9%）进行了多次统计学检验的校正。44 项（86.3%）研究基于单个结局进行了样本量计算，6 项（11.8%）研究基于多个结局进行了样本量计算。然而，在针对单一主要结局进行计算的研究中，有 20 项（45.5%）根据多个主要结局得出结论。21 项（41.2%）研究依赖于次要/未指定结局。主要结局是否达到（卡方，P=0.29）、样本量计算（P≥0.55）、β值（P=0.89）、α值（P=0.65）、多次统计学检验校正（P=0.59）、双侧α值（P=0.64）、无显著发现的支持（Fisher 精确检验，P=0.23）均与期刊影响因子无关。
皮肤科文献中 RCT 的统计报告水平较低。需要进一步努力提高这些报告水平。
