An Ecological Momentary Assessment Approachto the Study of Post-traumatic Stress Symptoms
in U.S. Military Service Members
Quinn M. Biggs, PhD, MPH,1 Carol S. Fullerton, PhD,1 Deborah Probe, MA,1 CDR Russell B. Carr, MD, USN, MC,1,2
Nicole Dacuyan, BS,1 Mackenzie Franz, BA,1 Maegan Paxton, BS,1 Leming Wang, MS,1 Robert Ursano, MD1
1Center for the Study of Traumatic Stress, Department of Psychiatry, Uniformed Services University of the Health Sciences, Bethesda, MD
2Walter Reed National Military Medical Center, Bethesda, MD

Introduction

Results (Cont.)

Ecological Momentary Assessment (EMA) is a relatively new method to capture
current experiences while respondents are engaged in normal daily routines.1,2
EMA maximizes validity and allows examination of the influences of context andtime on behavior. Repeated assessment of current experiences decreases recall
bias and increases reliability of data. EMA is based on paper and pencil
research methodology using daily diaries/journals. However, paper assessments
have drawbacks including respondents failing to complete assessments at thespecified time and the potential for forward-filling and back-filling ofassessments,3,4 which bring the validity of the data into question.5 Electronic
assessments overcome many of the limitations of paper assessments and areincreasingly common in EMA studies. To examine differences in assessment
methods, we compared assessment completion rates, usability, and participantreported benefits of assessments completed using paper and pencil versus
electronic tablets.

A total of 123 (6%) of paper assessments were not usable because they had
been completed prior to the assessment time (n = 31), after the assessment
time (n = 41), the completion time was not recorded (n = 50), or the participant
did not meet minimum data inclusion requirements (n = 1). Conversely, all of theelectronic assessments were usable. The average number of usable
assessments per participant was higher for paper (47.0) than electronic (33.8).
A post-assessment was completed by 62 participants (41 paper, 21 electronic).
There were no significant differences in ease of use, focus on mental state,
attention to bodily changes, positive changes in behavior, or overall helpfulnessof daily assessments completed by paper versus electronic methods (Figure 1).
In these comparisons, participants who completed both paper and electronic
assessments were included in the electronic group.
Figure 1. Ease of Use and Helpfulness of Daily Diary Assessments

Methods

Daily Diary assessments:
7.4
7.4...were easy to complete

Participants: Data for this investigation were drawn from the Daily Diary Study,
an EMA study tracking variability in post-traumatic stress symptoms (PTSS) overtime. Current and former U.S. military service members (N = 80) were recruitedfrom the behavioral health clinic at a large military medical center. A minimallevel of PTSS was required to join the study. Of enrollees, 69 complete at least
one EMA and 68 met minimum data inclusion requirements. Participants wereage 19 – 67 (M = 36.6, SD = 10.3) and primarily male (55.9%), Caucasian(73.5%), and in the Navy (42.1%) or Army (36.3%).

6.3
7.1

6.3

…overall, were helpful for me

Participants using electronic
assessments were significantly
more likely than participants using
paper assessments to report thatthey would use Daily Diary
assessments on their own if madeavailable (p = .02) (Figure 2).

Phase 2: Participants 51 – 80 weregiven electronic assessments withthe option to complete paper
assessments as needed.

7.1

2

3

45
Mean

Measures:• Daily Assessments: Each PTSS assessment included 26-items measuring
symptoms of post traumatic stress, depression, and generalized anxiety.
Sleep, pain, substance use, medication use, mental health care, and social
support were included on one assessment per day.
• Post-assessment: Five items asked the participant to rate the daily
assessments on ease of use and personal helpfulness on a 1 = Not at All to
10 = Very Much scale. One item asked if the participant would use the daily
assessments on his or her own if made available, Yes or No.
Data Analysis: Assessments were reviewed for compliance with assessment
procedures (i.e., completion time) and marked as usable or not usable for data
analysis. Analyses of paper and electronic methods included frequency ofusable assessments and participants, and significance tests (chi-square or ttests) to determine differences on the six post-assessment items.

Results
A total of 3026 assessments were collected from 69 participants (Table 1).
Three participants completed primarily electronic assessments (n = 153) andsome paper assessments (n = 15) when their electronic tablet was not available.
Table 1. Number of Assessments and Participants
Total

Paper

Electronic

Paper &Electronic

Assessments

3026

2048

810

168

Participants

6942243

43.9

48.8

33.8

56.0

Assessments

123

123

00

Participants

1100

Assessments

2903

1925

810

168

Participants

68

4124

3

Average # Assessments

42.7

47.0

33.8

56.0

Not Usable

Usable6789

Figure 2. Use of Daily Assessments
100%

76.2%

75%
50%

44.4%

25%
0%

Paper

Assessments were fixed interval,
four hours apart, and were to becompleted within six hours. The
date and time for completion waswritten on each paper assessment
and participants recorded when theassessment was completed.
Electronic assessments were only accessible at assessment times. Options forassessment reminders were offered to all participants. After the 15-day period ofdaily assessments, participants completed the post-assessment.

Paper
Electronic

4.3
4.6

...resulted in positive changes in my behavior

1Phase 1: Participants 1 – 50 were
given paper assessments.

Average # Assessments

8.2...helped me pay more attention to bodilychanges

Procedures: Participants wereasked to complete four Daily Diary
assessments per day for 15 days.

Assessments & Participants

7.2...helped me focus more on my mental stateElectronic

Considerations in Electronic Assessment:
PROS• Greater Control
oAssessment time windowoAlarm reminders
oCan vary item order• Interactive program incentives/feedback encourage participation• Wireless transfer ensures data are received and backed-upCONS• Cost for purchase, software development, updates, tech problems• Risk of damage, theft, or loss, but devices can be tracked• Electronic devices not permitted in some security sensitive locations

Discussion
In the Daily Diary Study, both paper and electronic EMAs were reported to beeasy to complete and, on average, participants completed more than half of theassessments. Many paper assessments were not usable because participants
did not complete them on time or did not record the time they were completed. Incontrast, all electronic assessments were on time and usable because electronicassessments were only accessible at the programmed times. However, theaverage number of assessments per participant was lower for electronic thanpaper. Regardless of assessment method, repeated assessments helped
participants monitor their mental and physical state and make positive changes
in behavior. Participants using electronic assessments were more likely tocontinue using daily assessments if available.
The potential applications of EMAs, paper or electronic, in behavioral health careinclude: (1) increased symptom monitoring to inform clinical decisions andprovide early intervention, (2) improved patient-provider communication
regarding symptoms, (3) development of behavioral and pharmacologicaltreatments tailored to the patient’s specific needs, and (4) the feedback fromself-monitoring can improve health through changes in personal lifestyle.

References
1Stone, A. A., & Shiffman, S. S. (1994). Ecological Momentary Assessment (EMA) In Behavioral Medicine.

Annals of Behavioral Medicine, 16, 199-202.
2Wenze, S. J., & Miller, I. W. (2010). Use of ecological momentary assessment in mood disorders research.

Clinical Psychology Review, 30(6), 794-804. doi: S0272-7358(10)00101-7 [pii] 10.1016/j.cpr.2010.06.007[doi]
3Stone, A. A., Shiffman, S. S., Schwartz, J. E., Broderick, J. E., & Hufford, M. R. (2002). Subject
noncompliance with paper diaries. British Medical Journal, 324, 1193-1194.
4Stone, A. A., Broderick, J. E., Schwartz, J. E., Shiffman, S. S., Litcher-Kelly, L., & Calvanese, P. (2003).
Intensive momentary reporting of pain with an electronic diary: Reactivity, compliance, and patientsatisfaction. Pain, 104, 343-351.
5Bolger, N., Davis, A., & Rafaeli, E. (2003). Diary methods: capturing life as it is lived. Annual Review ofPsychology, 54, 579-616. doi: 10.1146/annurev.psych.54.101601.145030 [doi] 101601.145030 [pii]The views expressed in this presentation are those of the author(s) and do not reflect the official policyof the Department of Army/Navy/Air Force, Department of Defense, or U.S. Government.

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