Uhlig Constantin E, Seitz Berthold, Eter Nicole, Promesberger Julia, Busse Holger
Department of Ophthalmology, University of Muenster Medical Center, Muenster, Germany.
Department of Ophthalmology, Saarland University Medical Center, Homburg/Sarr, Germany.
PLoS One. 2014 Oct 14;9(10):e108441. doi: 10.1371/journal.pone.0108441. eCollection 2014.
To evaluate the relative efficiencies of five Internet-based digital and three paper-based scientific surveys and to estimate the costs for different-sized cohorts.
Invitations to participate in a survey were distributed via e-mail to employees of two university hospitals (E1 and E2) and to members of a medical association (E3), as a link placed in a special text on the municipal homepage regularly read by the administrative employees of two cities (H1 and H2), and paper-based to workers at an automobile enterprise (P1) and college (P2) and senior (P3) students. The main parameters analyzed included the numbers of invited and actual participants, and the time and cost to complete the survey. Statistical analysis was descriptive, except for the Kruskal-Wallis-H-test, which was used to compare the three recruitment methods. Cost efficiencies were compared and extrapolated to different-sized cohorts.
The ratios of completely answered questionnaires to distributed questionnaires were between 81.5% (E1) and 97.4% (P2). Between 6.4% (P1) and 57.0% (P2) of the invited participants completely answered the questionnaires. The costs per completely answered questionnaire were $0.57-$1.41 (E1-3), $1.70 and $0.80 for H1 and H2, respectively, and $3.36-$4.21 (P1-3). Based on our results, electronic surveys with 10, 20, 30, or 42 questions would be estimated to be most cost (and time) efficient if more than 101.6-225.9 (128.2-391.7), 139.8-229.2 (93.8-193.6), 165.8-230.6 (68.7-115.7), or 188.2-231.5 (44.4-72.7) participants were required, respectively.
The study efficiency depended on the technical modalities of the survey methods and engagement of the participants. Depending on our study design, our results suggest that in similar projects that will certainly have more than two to three hundred required participants, the most efficient way of conducting a questionnaire-based survey is likely via the Internet with a digital questionnaire, specifically via a centralized e-mail.
评估五种基于互联网的数字科学调查和三种纸质科学调查的相对效率，并估算不同规模队列的成本。
通过电子邮件向两家大学医院（E1和E2）的员工以及一个医学协会（E3）的成员发送参与调查的邀请，在两个城市（H1和H2）行政员工经常阅读的市政主页的一篇特殊文本中放置链接，向一家汽车企业（P1）的工人、一所学院（P2）的人员和高年级（P3）学生进行纸质调查。分析的主要参数包括受邀者和实际参与者的数量，以及完成调查的时间和成本。除了用于比较三种招募方法的Kruskal-Wallis-H检验外，统计分析均为描述性分析。比较成本效率并推算至不同规模的队列。
完整回答问卷数与发放问卷数的比率在81.5%（E1）至97.4%（P2）之间。受邀参与者中6.4%（P1）至57.0%（P2）完整回答了问卷。每份完整回答问卷的成本为0.57美元至1.41美元（E1 - 3），H1和H2分别为1.70美元和0.80美元，P1 - 3为3.36美元至4.21美元。根据我们的结果，如果分别需要超过101.6 - 225.9（128.2 - 391.7）、139.8 - 229.2（93.8 - 193.6）、165.8 - 230.6（68.7 - 115.7）或188.2 - 231.5（44.4 - 72.7）名参与者，那么包含10、20、30或42个问题的电子调查估计在成本（和时间）方面最具效率。
研究效率取决于调查方法的技术模式和参与者的参与度。根据我们的研究设计，我们的结果表明，在肯定需要超过两三百名参与者的类似项目中，进行问卷调查最有效的方式可能是通过互联网使用数字问卷，特别是通过集中式电子邮件。
