Byrne Christopher M, Harrison James D, Young Jane M, Selby Warwick S, Solomon Michael J
Surgical Outcomes Research Centre, Sydney South West Area Health Service & University of Sydney, Australia.
J Clin Epidemiol. 2007 Dec;60(12):1312-4. doi: 10.1016/j.jclinepi.2007.04.005. Epub 2007 Aug 24.
To determine whether including the study questionnaire with a letter of invitation improves the response rate in a telephone-based survey.
This randomized controlled trial was part of a larger study to assess patient preferences for novel and controversial treatments for inflammatory bowel disease at Royal Prince Alfred Hospital, a tertiary referral teaching hospital in Sydney, Australia.
Of 270 eligible patients, 124 (46%) were randomized to receive the questionnaire plus invitation whereas 146 (54%) were in the control group receiving a letter of invitation only. The consent rate was 26% for those receiving the questionnaire and 36% for the control group. The odds ratio for consent to participate among those sent the questionnaire to those not sent the questionnaire was 0.63 (95% CI=0.37-1.07).
This study found that the advance mailing of a questionnaire to potential participants in a telephone survey reduced the likelihood of their participation.
确定在邀请函中附上研究问卷是否能提高电话调查的回复率。
这项随机对照试验是一项更大规模研究的一部分，该研究旨在评估澳大利亚悉尼一家三级转诊教学医院——皇家阿尔弗雷德王子医院中患者对炎症性肠病新型及有争议治疗方法的偏好。
在270名符合条件的患者中，124名（46%）被随机分配接受问卷加邀请函，而146名（54%）在对照组，仅收到邀请函。收到问卷者的同意率为26%，对照组为36%。收到问卷者与未收到问卷者同意参与的比值比为0.63（95%置信区间=0.37 - 1.07）。
本研究发现，在电话调查中提前向潜在参与者邮寄问卷会降低他们参与的可能性。
