Felix Lambert, Keating Patrick, McCambridge Jim
Department of Social & Environmental Health Research, Faculty of Public Health & Policy, London School of Hygiene & Tropical Medicine, London, UK.
Department of Health Sciences, University of York, York, UK.
BMC Med Res Methodol. 2015 Apr 24;15:41. doi: 10.1186/s12874-015-0032-z.
Informed consent is the foundation of the ethical conduct of health research. Obtaining informed consent may unwittingly interfere with the data collected in research studies, particularly if they concern sensitive behaviours that participants are requested to report on. To address gaps in evidence on such research participation effects, we conducted a methodological experiment evaluating the impact of the informed consent procedure on participants' reporting behaviour, specifically on their self-report of drinking behaviour as measured by Alcohol Use Disorder Identification Test (AUDIT).
A two arm double blinded randomised controlled trial was used. University students present in London student unions at the time of recruitment were contacted in two phases (an initial run-in phase followed by the main phase). Those providing positive responses to verbal questions: 1) "are you a student?"; 2) "do you drink alcohol?"; 3) "would you like to take part in a brief health survey, which will take around 5 minutes?" were recruited. Participants received one of the two envelopes by chance, with the sequence generated by an online random sequence generator. One contained the participant information sheet, informed consent form and the AUDIT questionnaire (the intervention group), while the other contained only the AUDIT questionnaire (the comparator group). The primary outcome was the mean AUDIT score, which ranges from 0 to 40. The secondary outcome was the proportion of participants in each group scoring 8 or more on the AUDIT, the threshold score for hazardous and harmful drinking warranting intervention.
A total of 380 participants were successfully recruited, resulting in 190 participants in each group, of which 378 were included in the final analysis. There is no evidence of any statistically significant difference between groups in the primary outcome. A statistically significant difference in the secondary outcome was found in the run-in phase only, and not in the main phase, or overall. Moreover, between-group outcome differences between the two phases suggest an important influence of setting on reporting behaviour.
There is no strong evidence that completion of informed consent itself alters self-reporting behaviour with regards to alcohol, though the effect of settings needs to be further studied.
知情同意是健康研究伦理行为的基础。获取知情同意可能会在不经意间干扰研究中收集的数据，特别是当研究涉及参与者被要求报告的敏感行为时。为了填补关于此类研究参与效应的证据空白，我们进行了一项方法学实验，评估知情同意程序对参与者报告行为的影响，具体是对他们通过酒精使用障碍识别测试（AUDIT）测量的饮酒行为自我报告的影响。
采用双臂双盲随机对照试验。在招募时身处伦敦学生会的大学生分两个阶段被联系（初始的导入阶段随后是主要阶段）。对以下口头问题给出肯定回答的人被招募：1）“你是学生吗？”；2）“你饮酒吗？”；3）“你愿意参加一项简短的健康调查吗，大约需要5分钟？”。参与者随机收到两个信封中的一个，序列由在线随机序列生成器生成。一个包含参与者信息表、知情同意书和AUDIT问卷（干预组），另一个只包含AUDIT问卷（对照组）。主要结局是AUDIT平均得分（范围为0至40）。次要结局是每组中AUDIT得分8分或更高的参与者比例，这是需要进行干预的危险和有害饮酒的阈值分数。
总共成功招募了380名参与者，每组190名，其中378名纳入最终分析。在主要结局方面，没有证据表明两组之间存在任何统计学上的显著差异。仅在导入阶段发现次要结局存在统计学上的显著差异，在主要阶段或总体上未发现。此外，两个阶段之间的组间结局差异表明环境对报告行为有重要影响。
没有有力证据表明完成知情同意本身会改变关于酒精的自我报告行为，不过环境的影响需要进一步研究。
