Shahar E, Bisgard K M, Folsom A R
Division of Epidemiology, School of Public Health, University of Minnesota, Minneapolis 55454-1015.
Epidemiology. 1993 Sep;4(5):480-2.
As part of a mailed health survey, we investigated the effect on the response rate of a request to explain refusal to participate. Subjects (N = 1,240) were randomized either to receive or not to receive, with the first mailing, a letter requesting an explanation of their decision not to fill out the questionnaire, if they chose that option. There was a slightly higher cumulative response during most of the study from subjects who had been sent the request, but little difference between the two study groups in the ultimate response rate [80% from the intervention group vs 83% from the control group; response rate difference = -3%; 95% confidence limits (CL) = -7%, 1%]. Of 209 individuals who were sent the request and did not return the questionnaire, only 15 (7%) sent back an explanation. A request to explain a refusal to participate in a mail survey neither jeopardized the response rate nor enhanced it.
作为一项邮寄式健康调查的一部分，我们研究了要求解释拒绝参与调查这一行为对回复率的影响。受试者（N = 1240）被随机分为两组，第一组在收到邮件时会收到一封信，信中要求他们如果选择不填写问卷需解释其决定，而第二组则不会收到该信件。在研究的大部分时间里，收到该要求的受试者的累积回复率略高，但两组最终的回复率差异不大[干预组为80%，对照组为83%；回复率差异 = -3%；95%置信区间（CL）= -7%，1%]。在收到要求但未返回问卷的209人中，只有15人（7%）寄回了解释。要求解释拒绝参与邮寄调查既不会降低回复率，也不会提高回复率。
