Table 3

Total costs comparing $2 and $5 conditions and one versus two mailings

$2 condition

$5 condition


First Mailing-total cost per participant*

$5.25

$8.25

First mailing response rate

47.67%

57.77%

Total cost/returned survey ($)

$11.01

$14.28

Second Mailing-total cost per participant**

$2.40

$2.40

Second mailing response rate

33.91%

22.50%

Total cost/returned survey ($)

$7.08

$10.67

Final Response

Cumulative response rate

65.41%

67.27%

Total cost/returned survey ($)

$9.95

$13.77


*total cost per survey included survey packet, incentive and reminder postcard

**total cost per survey included survey packet only

Griffin et al. BMC Medical Research Methodology 2011 11:81   doi:10.1186/1471-2288-11-81

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