1. Does a Wireless Incentive Structure Improve Retention, Subject
Satisfaction and Safety in Intimate Partner Violence Research?
Melissa A. Rodgers, BA1, Alexandra L. Hanlon, Ph.D2, Elizabeth M. Datner, MD1, Karin V. Rhodes, MD, MS1
1School of Medicine, University of Pennsylvania, 2School of Nursing, University of Pennsylvania
 Effective evidence-based interventions are
needed for patients with intimate partner
violence (IPV) and other psychosocial risks.
 Innovative technologies may address
methodological weaknesses of previous
research with this at-risk population including:
 high rates of attrition
 safety concerns contacting participants
 inadequate outcome measures.
 Generic bank cards allow for wireless, flexible,
and immediate payment for data collection that
can be conducted remotely.
Background
Demographics for Card vs. Cash paid individuals
To assess the impact of a wireless incentive
payment on subject retention, satisfaction, and
safety compared to those paid with cash.
Objectives
Card
(n=103)
Cash
(n=112)
Difference in
Proportions
95% CI P
Age ( Med / IQR) 32 (25-41) 31 (23-35) -1.64* -4.46 – 1.19 0.7115
African American (N / %) 76 74.5% 75 68.2% 6% -0.18 – 0.06 0.3630
Marital Status: Single 75 72.8% 84 75.7% 3% -0.09 – 0.15 0.6424
Education: Less than High School Grad 20 19.4% 23 20.7% 1% -0.09 – 1.20 0.8654
Unemployed (outside the home) 55 53.4% 59 52.7% 1% -0.14 – 0.13 0.9159
Income: Less than $10,000 year 26 28.6% 30 29.4% 1% -0.12 – 0.14 0.8978
Children: No Children (<18) in Home 44 46.8% 44 43.6% 1% -0.13 – 0.14 0.9510
IPV Severity: CTS2S Score ( Med / IQR) 7.5 (3-9) 12.1 (4.5-16) 4.73* 2.24 – 7.22 0.0054
Alcohol Severity: AUDIT Score 7.9 (4- 9) 9.3 (5 - 11) 1.40* -0.18 – 2.99 0.9669
*Difference in Means for Continuous Variables
 Prospective cohort study using longitudinal
data collected during a large randomized
control trial of an IPV intervention.
 Female patients age 18-64 are recruited from
an urban ED setting for a 3-12 month study
funded by NIAAA.
 All enrollees meet study eligibility criteria of
risky drinking and experience with IPV in the
past 3 months, and are compensated $10 for
completing each of the 12 weekly automated
phone surveys.
 A natural experiment occurred; the first 112
participants enrolled were paid cash, in
person, and the next 103 participants
received wireless payments via a bank card.
 Adjusting for significant demographics, a
backward elimination GEE Model examines
the association between payment type, and
the number of calls completed over the 12
weeks.
 Participants were asked about their safety
and satisfaction with the incentive structure
during 3-month interviews.
Methods
 The mean number of calls for the wireless
incentive group is 8.3 (SD=3.54), which is
significantly greater than the cash incentive
group (M=6.0; SD=3.79).
 Overall, 45% of those paid with cash
completed 10-12 calls vs. 22% who were
paid cash. On average, card participants
completed 70% of their calls while those
paid cash completed 50%.
 Payment type groups are demographically
similar with regard to age, marital status,
education, employment, and alcohol severity,
but vary in terms of IPV severity.
 Card participants were more likely to
complete a phone survey each week
(OR=1.52; CI 1.00-2.29).
 While completion decreased over time
(OR=1.06; CI=1.03-1.10), the number of calls
completed declined more rapidly for those
with the cash incentive (p=0.0016).
 Over 90% of participants who received a gift
card expressed satisfaction with the payment
method and phone survey; 60% indicated
that they preferred the gift card incentive.
 At 3-months, there was no difference in self-
reported safety between the two groups.
Results
 A wireless incentive structure may help to
improve retention in clinical research,
particularly with repetitive outcome measures
that can be collected remotely.
 Patient satisfaction with the gift card reinforces
their use with this vulnerable study population.
 Future analyses should include a more direct
measurement of whether the cards alleviate
potential safety risks for involved participants.
Conclusions
 Participants included in this analysis are
female, were recruited from two urban ED
departments, and met study eligibility criteria of
risking drinking (AUDIT>3) and experience of
IPV in the past 3 months(CTS2S ≥ 1).
 Data was not collected during a concurrent time
period for the two payment type groups.
Limitations
% of Participants by Number of Completed Calls
Cash
(n=112)
Card
(n=103)
22%
27%
18%
33%
45%
29%
11% 16%
10-127-94-61-3
Number of Calls