Jezek Andrea Huber, Ekholm Ola, Thygesen Lau Caspar, Christensen Anne Illemann
National Institute of Public Health, University of Southern Denmark, Copenhagen K, Denmark.
Eur J Public Health. 2025 Apr 1;35(2):256-262. doi: 10.1093/eurpub/ckae176.
Declining response proportions in health surveys may lead to increased non-response bias. Multiple reminders are often used to increase response proportions, and, thus, we aimed to determine if the use of reminders decreased the magnitude of non-response bias among web-mode invited in the Danish National Health Survey 2023. In the Danish National Health Survey 2023, a national random sample of 23 467 individuals (aged ≥16 years) with residence in Denmark were invited by a secure electronic mail service. Invited individuals received up to five inquiries: (i) web invitation, (ii) web reminder, (iii) paper invitation including a questionnaire and a prepaid return envelope, (iv) paper reminder, and (v) paper reminder including a questionnaire and a prepaid return envelope. The cumulative response proportions after first-, second-, third-, fourth-, and fifth inquiries were 19.1%, 28.9%, 37.2%, 39.3%, and 42.0%, respectively. In general, third, fourth, and fifth mailing respondents were more often men, at younger ages, with non-Western backgrounds, and unmarried compared to first mailing respondents. Furthermore, third, fourth, and fifth mailing respondents were in general found to have less favorable health behavior than first mailing respondents, but also a lower prevalence of fair or poor self-rated health and long-standing health problems. In conlusion, reminders are an effective way to increase the response proportion. Furthermore, the use of reminders was found to decrease the magnitude of non-response bias; however, the decrease was small due to the low number of individuals responding after fourth and fifth inquiries.
健康调查中回应比例的下降可能会导致无回应偏差增加。通常会使用多次提醒来提高回应比例，因此，我们旨在确定在2023年丹麦国家健康调查中，对网络模式邀请对象使用提醒是否会降低无回应偏差的程度。在2023年丹麦国家健康调查中，通过安全电子邮件服务邀请了23467名居住在丹麦的16岁及以上的全国随机样本个体。受邀个体最多收到五次询问：（i）网络邀请，（ii）网络提醒，（iii）包含问卷和预付回邮信封的纸质邀请，（iv）纸质提醒，以及（v）包含问卷和预付回邮信封的纸质提醒。第一次、第二次、第三次、第四次和第五次询问后的累积回应比例分别为19.1%、28.9%、37.2%、39.3%和42.0%。一般来说，与第一次邮寄的受访者相比，第三次、第四次和第五次邮寄的受访者男性更多、年龄更小、具有非西方背景且未婚。此外，总体而言，第三次、第四次和第五次邮寄的受访者被发现健康行为不如第一次邮寄的受访者，但自评健康状况一般或较差以及长期健康问题的患病率也较低。总之，提醒是提高回应比例的有效方法。此外，发现使用提醒可降低无回应偏差的程度；然而，由于第四次和第五次询问后回应的个体数量较少，降低幅度较小。
