@Article{信息:doi 10.2196 / / jmir。3734，作者=“Domnich, Alexander和Panatto, Donatella和Signori, Alessio和Bragazzi, Nicola Luigi和Cristina, Maria Luisa和Amicizia, Daniela和Gasparini, Roberto”，标题=“基于web的事实性健康知识调查的无控制管理:无时间与有时间测验的随机研究”，期刊=“J Med Internet Res”，年=“2015”，月=“Apr”，日=“13”，卷=“17”，数=“4”，页=“e94”，关键词=“知识问卷;在线调查;时间限制;不受控制的检验管理;作弊;e-cheating;背景:健康知识和素养是健康的主要决定因素之一。通过基于网络的调查对这些问题的评估正在持续增长。研究表明，大约五分之一的受访者在事实性知识项目上提交了抄袭的答案或作弊，这可能会导致测量误差。 However, little is known about methods of discouraging cheating in Web-based surveys on health knowledge. Objective: This study aimed at exploring the usefulness of imposing a survey time limit to prevent help-seeking and cheating. Methods: On the basis of sample size estimation, 94 undergraduate students were randomly assigned in a 1:1 ratio to complete a Web-based survey on nutrition knowledge, with or without a time limit of 15 minutes (30 seconds per item); the topic of nutrition was chosen because of its particular relevance to public health. The questionnaire consisted of two parts. The first was the validated consumer-oriented nutrition knowledge scale (CoNKS) consisting of 20 true/false items; the second was an ad hoc questionnaire (AHQ) containing 10 questions that would be very difficult for people without health care qualifications to answer correctly. It therefore aimed at measuring cribbing and not nutrition knowledge. AHQ items were somewhat encyclopedic and amenable to Web searching, while CoNKS items had more complex wording, so that simple copying/pasting of a question in a search string would not produce an immediate correct answer. Results: A total of 72 of the 94 subjects started the survey. Dropout rates were similar in both groups (11{\%}, 4/35 and 14{\%}, 5/37 in the untimed and timed groups, respectively). Most participants completed the survey from portable devices, such as mobile phones and tablets. To complete the survey, participants in the untimed group took a median 2.3 minutes longer than those in the timed group; the effect size was small (Cohen's r=.29). Subjects in the untimed group scored significantly higher on CoNKS (mean difference of 1.2 points, P=.008) and the effect size was medium (Cohen's d=0.67). By contrast, no significant between-group difference in AHQ scores was documented. Unexpectedly high AHQ scores were recorded in 23{\%} (7/31) and 19{\%} (6/32) untimed and timed respondents, respectively, very probably owing to ``e-cheating''. Conclusions: Cribbing answers to health knowledge items in researcher-uncontrolled conditions is likely to lead to overestimation of people's knowledge; this should be considered during the design and implementation of Web-based surveys. Setting a time limit alone may not completely prevent cheating, as some cheats may be very fast in Web searching. More complex and contextualized wording of items and checking for the ``findability'' properties of items before implementing a Web-based health knowledge survey may discourage help-seeking, thus reducing measurement error. Studies with larger sample sizes and diverse populations are needed to confirm our results. ", issn="1438-8871", doi="10.2196/jmir.3734", url="//www.mybigtv.com/2015/4/e94/", url="https://doi.org/10.2196/jmir.3734", url="http://www.ncbi.nlm.nih.gov/pubmed/25872617" }