Despite its importance, underreporting of the active content of experimental and comparator interventions in published literature has not been previously examined for behavioural trials. We assessed completeness and variability in reporting in 142 randomised controlled trials of behavioural interventions for smoking cessation published between 1/1996 and 11/2015. Two coders reliably identified the potential active components of experimental and comparator interventions (activities targeting behaviours key to smoking cessation and qualifying as behaviour change techniques, BCTs) in published, and in unpublished materials obtained from study authors directly. Unpublished materials were obtained for 129/204 (63%) experimental and 93/142 (65%) comparator groups. For those, only 35% (1200/3403) of experimental and 26% (491/1891) of comparator BCTs could be identified in published materials. Reporting quality (#published BCTs/#total BCTs) varied considerably between trials and between groups within trials. Experimental (vs. comparator) interventions were better reported (B(SE) = 0.34 (0.11), p < .001). Unpublished materials were more often obtained for recent studies (B(SE) = 0.093 (0.03), p = .003) published in behavioural (vs. medical) journals (B(SE) = 1.03 (0.41), p = .012). This high variability in underreporting of active content compromises reader's ability to interpret the effects of individual trials, compare and explain intervention effects in evidence syntheses, and estimate the additional benefit of an experimental intervention in other settings.

中文翻译：

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行为干预积极内容的少报：戒烟干预随机试验的系统回顾和荟萃分析。


尽管其重要性，但在已发表的文献中对实验干预措施和比较干预措施的活性内容的少报尚未在行为试验中得到检验。我们评估了 1996 年 1 月至 2015 年 11 月发表的 142 项戒烟行为干预随机对照试验报告的完整性和变异性。两名编码员在直接从研究作者处获得的已发表和未发表的材料中可靠地识别了实验和比较干预措施（针对戒烟关键行为的活动，并符合行为改变技术，BCT）的潜在活性成分。 129/204 (63%) 实验组和 93/142 (65%) 比较组获得未发表的材料。对于这些，在已发表的材料中只能识别出 35% (1200/3403) 的实验 BCT 和 26% (491/1891) 的比较 BCT。报告质量（#已发布的 BCT/#总 BCT）在试验之间以及试验中的组之间差异很大。实验（与比较）干预措施的报告更好（B(SE) = 0.34 (0.11)，p < .001）。行为（与医学）期刊上发表的近期研究（B(SE) = 0.093 (0.03)，p = .003）更常获得未发表的材料（B(SE) = 1.03 (0.41)，p = .012） 。活动内容漏报的这种高度可变性损害了读者解释个别试验的效果、比较和解释证据综合中的干预效果以及估计其他环境中实验干预的额外益处的能力。