Dallosso H M, Matthews R J, McGrother C W, Clarke M, Perry S I, Shaw C, Jagger C
Department of Epidemiology and Public Health, University of Leicester, UK.
BJU Int. 2003 May;91(7):631-6. doi: 10.1046/j.1464-410x.2003.04172.x.
To investigate nonresponse bias in a postal survey on urinary symptoms in people aged >or= 40 years.
Nonresponders to a postal survey on incontinence and other urinary symptoms were studied. A random sample of 1050 nonresponders (stratified for age and sex) was traced by a team of interviewers. Eligible nonresponders were asked several questions from the postal questionnaire, and their reason for not participating in the postal survey.
Only 1% of those not responding were not traced in person or accounted for, and 12% were identified as not eligible to be in the survey sample (moved from address, deceased, residential home). Half of the eligible nonresponders (51%) did not answer the interviewer's questions, the main reason being general unwillingness or disinterest. The number in whom poor health was the reason increased with age. Comparing nonresponders who answered the interviewer's questions with a random sample of responders from the postal survey showed little difference in the reporting of urinary symptoms, although there were differences in general health and long-term health problems. Separate analyses by age showed greater reporting of some urinary symptoms and of poorer general health in the older nonresponders (>or= 70 years).
Overall, for people aged >or= 40 years there was no evidence of a nonresponse bias in the reporting of urinary symptoms, providing confidence in such prevalence rates. However, poorer general health and greater reporting of some urinary symptoms by the older nonresponders (>or= 70 years) suggests prevalence rates in this age group may be underestimated.
调查针对40岁及以上人群进行的关于泌尿系统症状的邮寄调查中的无应答偏倚。
对一项关于尿失禁及其他泌尿系统症状的邮寄调查的无应答者进行研究。一组访员追踪了1050名无应答者的随机样本（按年龄和性别分层）。符合条件的无应答者被问及邮寄问卷中的几个问题以及他们不参与邮寄调查的原因。
未应答者中只有1%未被亲自追踪到或未得到说明，12%被确定不符合调查样本资格（已搬离原地址、已去世、住在养老院）。一半符合条件的无应答者（51%）未回答访员的问题，主要原因是普遍不愿意或不感兴趣。因健康状况不佳而未应答的人数随年龄增长而增加。将回答访员问题的无应答者与邮寄调查的随机应答者样本进行比较，泌尿系统症状的报告差异不大，尽管在总体健康状况和长期健康问题方面存在差异。按年龄进行的单独分析显示，年龄较大的无应答者（70岁及以上）对某些泌尿系统症状的报告更多，总体健康状况也较差。
总体而言，对于40岁及以上人群，在泌尿系统症状报告方面没有无应答偏倚的证据，这为此类患病率提供了可信度。然而，年龄较大的无应答者（70岁及以上）总体健康状况较差且对某些泌尿系统症状的报告更多，这表明该年龄组的患病率可能被低估了。
