Does a digitalized single-mode survey lead to similar participation as a mixed-mode survey?

摘要: Background Choice of survey administration mode in surveys mapping public health may influence the participation rates and hence the generalizability of the results. The aim of the study was, in a randomized design, to examine whether three digital invitation letters (i.e., single-mode administration) lead to a similar participation as two digital letters and three physical letters (mixed-mode administration) mailed with a shorter time interval between reminders. Methods The study utilizes data on 10,000 individuals (≥20 years) who participated in The Danish Capital Region Health Survey in 2017 and were re-invited in 2021. Citizens who were registered to receive digital mail from public authorities were randomized into two groups; the intervention group that received three digital letters (day 0, 21, 46; N = 4,745), and the control group that received two digital letters (day 0 and 7 …