Article Text
Statistics from Altmetric.com
Postal questionnaires are frequently used in research. One way of improving response rates is to use lotteries, although the evidence for their effectiveness is equivocal.1-4 An alternative, or complementary, approach to using lotteries is to make direct payments to survey responders. Few trials have evaluated direct payment compared with lotteries.3
Methods
Questionnaires about menopause services in the North West of England were sent to a random sample of 1000 women aged 40 to 65 during September to November 1997. The questionnaires included questions about use of hormone replacement therapy (HRT) and women's demographic characteristics.
The sample of women were randomised in a 2 × 2 factorial trial to estimate the effectiveness of the two forms of incentive and their potential interaction within a single study. Unequal randomisation of 3 to 1 favouring no direct payment was used to minimise research costs, which led …
Footnotes
-
Funding: NHS NorthWest Region Research Practices Initiative.
-
Conflicts of interest: none.