From: A randomised trial and economic evaluation of the effect of response mode on response rate, response bias, and item non-response in a survey of doctors
Group allocation
Simultaneous mixed
Sequential mixed
Online
Total
Paper returned (%)
78.86
61.62
3.45
53.78
Online completed (%)
21.14
38.38
96.55
46.22
Total number of surveys
175
185
116
476