This document summarizes research on predicting who will cash prepaid incentive checks for physician surveys. Two surveys of primary care physicians were conducted, one in the US and one international, both offering a prepaid incentive check. Results showed about one third cashed the check overall, with fewer "cheating" by cashing without completing the survey. Solo practitioners and internal medicine doctors were more likely to cheat. Providing an email address and easier online completion were associated with lower cheating rates and costs. Future research should focus on ways to boost online response and lower costs, especially for internal medicine physicians.

1. Cheaters vs. Good Samaritans:
Predicting Who Will Cash Prepaid
Incentive Checks
AAPOR 2016
Presented by
Robyn Rapoport, SSRS
Vice President, Health Care, Public Policy & International Research
C O A U T H O R S :
Michelle Doty, The Commonwealth Fund
Elizabeth Hamel, The Kaiser Family Foundation

2. 2
Outline
• Pre-incentives and Surveys of Physicians – Previous Research
• Background: Two Surveys with Primary Care Physicians
• Results
• Conclusions and Future Research
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3. 3
Background
• Use of pre-incentives considered a “best practice” in physician research
− Associated with meaningfully higher response rates vs. promised incentives
− “Cheaters” are those who cash the pre-incentive but do not complete the
survey
− “Good Samaritans” are those who complete the survey but do not cash the
pre-incentive
• Understanding who is likely to cash check among those who complete and do
not complete survey is critical in determining the cost of conducting research
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4. 4
US PCP Survey & International Health Policy (IHP) Survey
US PCP Survey IHP PCP Survey
Survey Mode
Mail recruit to self-administered paper
(12 pages – 49 questions) or
online survey
Mail recruit to self-administered paper
(8 pages – 51 questions) or
online survey
Population
US Primary Care Physicians,
stratified to oversample PCPs
working in low-income areas, etc.
US Primary Care Physicians,
nationally representative
(10 other countries also surveyed in this
research).
Sample Source SK&A SK&A
Weeks in Field 12 weeks – 2 wave design 14 weeks – 2 wave design
Sample Size 1,624 842
Pre-incentive $50 $25
Response Rate 34% 31%
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5. 5
Procedures
US PCP Survey IHP PCP Survey
Initial Mailing
Invitation letter with web link,
paper survey, $50 incentive check
Invitation letter with web link,
list of past IHP publications
Second Mailing
Cover letter with web link;
paper survey, $25 incentive check
Reminder Letter (s) Reminder letter with paper survey
Two reminder letters with paper survey
(Wave 1)
One reminder letter with paper survey
(Wave 2)
Postcard Reminders Two post card reminders Two post card reminders
Email Reminders Two email reminders
Five email reminders (Wave 1)
Three email reminders (Wave 2)
Phone Reminders One phone reminder
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6. Results

7. 7© ssrs | all rights reserved
Pre-Incentive Cashing Among All Survey Contacts
For both studies, approximately one third of the sample cashed the pre-incentive check;
a somewhat larger portion of the US PCP sample cashed
Cashed
37%
Not Cashed
63%
US PCP Study
Cashed
33%
Not Cashed
67%
IHP PCP Study

8. 8© ssrs | all rights reserved
Pre-Incentive Cashing by Survey Mode Among All Survey Contacts
Fewer than one in ten cashed (‘cheated’) among those who didn’t complete;
the vast majority of those who completed also cashed their pre-incentive check
8%
85% 80% 86%
92%
15% 20% 14%
Not
Completed
Total
Completed
Web
Complete
Mail Complete
IHP PCP Study
Cashed Not Cashed
8%
91% 90%
83%
93%
92%
9% 10%
17%
7%
Not
Completed/
Terminated
Total
Completed
Total
Complete/
Terminated
Web
Complete/
Terminated
Mail
Complete/
Terminated
US PCP Study
Cashed Not Cashed

9. 9© ssrs | all rights reserved
Completed Survey/Terminated Among All Survey Contacts
– Practice Characteristics
Highest completion rates among solo practitioners, pediatricians and FPs/GPs
28%
39%
27%
35%
36%
27%
33%
26%
32%
33%
35%
Multi (D)
PED (C)
IM (B)
FP/GP (A)
PED (C)
IM (B)
FP/GP (A)
9 + (D)
4 to 8 (C)
2 to 3 (B)
Solo (A)
PracticeSpecialty
Physician
SpecialtyPracticeSize
IHP PCP Study
BCD
32%
40%
34%
38%
39%
31%
37%
30%
36%
35%
40%
Multi (D)
PED (C)
IM (B)
FP/GP (A)
PED (C)
IM (B)
FP/GP (A)
9 + (D)
4 to 8 (C)
2 to 3 (B)
Solo (A)
PracticeSpecialty
Physician
SpecialtyPracticeSize
US PCP Study
BCD
B
B
BD
BD
B
B
BD
BD
ABCD denotes significant differences at the 95% confidence interval

10. 10
US PCP Survey IHP PCP Survey
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Completed Survey/Terminated Among All Survey Contacts
– Email Availability
Somewhat more likely to complete if have email address in sample
34%
36%
Completed/Terminated
30%
32%
Completed

11. 11
9%
5% 4% 3%4% 5% 6% 5%
Solo 2 to 3 4 to 8 9 or More
IHP PCP Study
Cheater Good Samaritan
7%
5% 4% 4%3% 3% 4% 3%
Solo 2 to 3 4 to 8 9 or More
US PCP Study
Cheater Good Samaritan
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Cheater & Good Samaritan Profiles by Practice Size
Most cheaters among solo practitioners; similar proportions of Good Samaritans across
practice size groupings
A B C D E F G H
A B C D E F G H
CEG
CEG
ABCDEFGH denotes significant differences at the 95% confidence interval

12. 12
6% 5% 4%4%
2% 3%
FP/GP Internal Medicine Pediatrics
US PCP Study
Cheater Good Samaritan
6% 6%
4%
6%
3%
5%
FP/GP Internal Medicine Pediatrics
IHP PCP Study
Cheater Good Samaritan
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Cheater & Good Samaritan Profiles by Physician Specialty
Somewhat fewer Cheaters among Pediatricians vs. other specialties; ratio of Cheaters to
Good Samaritans is highest among Internists
ABCDEF denotes significant differences at the 95% confidence interval
A B C D E F
A B C D E F
D
D
D
E

13. 13
6% 5% 4% 5%4%
2% 3% 4%
FP/GP Internal Medicine Pediatrics Multi-Specialty
US PCP Study
Cheater Good Samaritan
6%
7%
5% 5%
7%
2%
5% 5%
FP/GP Internal Medicine Pediatrics Multi-Specialty
IHP PCP Study
Cheater Good Samaritan
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Cheater & Good Samaritan Profiles by Practice Specialty
Similar pattern – Ratio of Cheaters to Good Samaritans is highest in IM Practices
ABCDEFGH denotes significant differences at the 95% confidence interval
A B C D E F G H
A B C D E F G H
D
D
D
D
D

14. 14
4%
6%
4%
2%
Email Available No Email
US PCP Study
Cheater Good Samaritan
D
4%
7%
5% 5%
Email Available No Email
IHP PCP Study
Cheater Good Samaritan
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Cheater & Good Samaritan Profiles by Email Availability
More cheaters among PCPs without an email address in both studies; more Good Samaritans
among PCPs with email addresses in US PCP study
ABCD denotes significant differences at the 95% confidence interval
A
A
A B C D
A B C D

15. 15
70%
30%
Good Samaritans
77%
23%
Completed & Cashed
73%
27%
Completed/Terminated & Cashed
49%
51%
Good Samaritans
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Survey Mode Among PCPs Who Complete the Survey
– Cashed Check vs. Good Samaritans
Good Samaritans are more likely to complete the survey online; those who
cash pre-incentive check are more likely to complete the mail survey
Mail Complete or
Terminate
Web Complete
or Terminate
Mail Complete
Web Complete
Mail Complete or
Terminate
Web Complete
or Terminate
Mail Complete
Web Complete
US PCP Study
US PCP Study

16. 16
Conclusions & Future Research
• PCPs who are sole practitioners are more likely to complete and also more likely
to cheat vs. PCPs in larger practices
• Cost/interview for Internists is higher than other PCPs - least likely to complete,
less likely to be a good Samaritan, more likely to cheat
 Similar pattern for PCPs in Internal Medicine practices
• Best options for ‘saving’ money – make it easier to complete survey online
• Longer mail survey (more pages) may induce more to complete web survey
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17. contact us
with any questions
@RobynRapoport | 484-840-4354 | rrapoport@ssrs.com
Robyn Rapoport
Vice President, Health Care, Public Policy & International Research