Development and Implementation of a Behavioral Digital Therapeutic Designed to Support, Educate, Screen and Remotely Monitor Patients With Chronic Pain
Phase: PHASE2
Conditions: Chronic Pain
Sponsor: University of Washington

Feasibility Study of 2MRx-CP Use by Patients with 
Chronic Pain 
Phase II: Protocol & Statistical Analysis Plan 
Prepared by Stephens Research Group: 
Yohali Burrola-Mendez, Maria Prado, Chialing Hsu, Kris (Pui Kwan) 
Ma, Ying Zhang, & Kari A. Stephens 
University of Washington  
Department of Family Medicine 
September 23, 2024 
NCT#: NCT06000007 

 
Table of Contents 
Feasibility Study of 2MRx-CP Use by Patients with Chronic Pain ............................................ 3 
Feasibility Study of 2MRx-CP Use by Patients with Chronic Pain: University of Washington 
Final Report ........................................................................................................................ 3 
Study’s Overview .................................................................................................................... 3 
Background ........................................................................................................................ 3 
Aims ................................................................................................................................... 3 
Methods ................................................................................................................................. 5 
References ......................................................................................................................... 8 
Appendixes ............................................................................................................................ 9 
Appendix 1. Outcome measures .......................................................................................... 9 
Eligibility Survey .................................................................................................................. 9 
Baseline Survey (T0) ........................................................................................................... 12 
1-Month, 3-Month and 6-Month Follow-up Survey ................................................................ 17 
Health Care Resource Utilization (HCRU) Survey ................................................................. 22 
mHealth App Usability Questionnaire .................................................................................. 23 
 
 
 

 
Feasibility Study of 2MRx-CP Use by Patients with 
Chronic Pain: University of Washington Final Report  
Study’s Overview 
Background 
Feasibility studies are preliminary studies designed to evaluate the methods and procedures 
for use in randomized control trials (1-3). These studies aim to identify necessary adjustments that 
could increase the likelihood of success of larger-scale research (i.e., a well powered efficacy trial)  
(4). Recently published guidelines emerged to assist researchers on the planning and evaluation of 
feasibility studies and prevent common misuses (3), which were not available when the original 
proposal was approved by NIH’s NCCIH.  
 
The feasibility randomized control trial (RCT) aimed to test the 2MRx-CP app (i.e., 2Morrow 
Inc.’s Salty app), a behavioral health app targeted at delivering Acceptance and Commitment 
Therapy and Cognitive Behavioral Therapy strategies and activities to improve patient function and 
quality of life. A two-arm feasibility RCT study was conducted with adult patients recruited from 
primary care settings in rural and urban areas and active self-reported experience of chronic pain. 
The study aims have been refined and enhanced to align with the latest published guidelines for 
feasibility trials, while still addressing the original objectives. 
 
Aims 
Aim 1. To assess acceptability, appropriateness and feasibility of 2MRx-CP digital therapeutic as 
an intervention for primary care patients with chronic pain. 
 
App Measure Selection: The preliminary usability and acceptance of the Salty app was 
measured to ensure alignment with the latest guidelines for feasibility trials while still 
addressing the core objective of evaluating the intervention for primary care patients with 
chronic pain. As part of this measurement selection, the mHealth App Usability Questionnaire 
(MAUQ) was used to measure preliminary usability, replacing the originally proposed 
Weiner and colleagues (2017, 
https://implementationscience.biomedcentral.com/articles/10.1186/s13012-017-0635-3) 
usability measure, due to its strong psychometric evidence and better alignment with 
construct definitions of evaluating a mobile app. Namely, the MAUQ provided a more 
robust evaluation of app usability, compared to the originally proposed measure. The 
MAUQ, the SaltyChP (i.e., a custom built measure developed by 2Morrow Inc. to help evaluate 
usability for product development and support marketability), and descriptives of app usage 
(i.e., total number of intervention arm patients that successfully engaged use of the app; days 
the app was used / proportion of days used that were possible; and, total number of badges 
earned out of the four that were possible) were used to evaluate preliminary usability and 
acceptance. 
 

 
Aim 2. To assess feasibility of recruitment, study uptake, and completion of study assessments. 
 
Feasibility Measure Selection: In alignment with standard measures used in feasibility 
randomized controlled trials, the following feasibility indicators were selected to assess 
recruitment procedures, retention, outcome measures’ adequacy, and feasibility of 
implementing the intervention (i.e., Salty app): 
 
1. Recruitment procedures: Ability to recruit a diverse sample of participants with various 
chronic pain diagnoses and exploring the reasons for ineligibility or study decline. 
2. Retention: Will participants stay engaged in the study? Survey completion rates by arm and 
timepoint. 
3. Outcomes measures adequacy: a) Are the measures acceptable, appropriate and relevant 
to the target population? b) Is there evidence of reliability and validity (including 
responsiveness to change) of measures in the target population? 
4. Intervention implementation: a) Was the intervention delivered as intended? b) Were 
participants engaged with the program components?  
 
Aim 3. To estimate the likely treatment efficacy effect size for a large RCT. 
 
Measures for Preliminary Response to Intervention: Recently published guidelines 
discourage estimating effect sizes in feasibility studies due to small sample sizes and 
unrepresentative samples (3). This can lead to inaccurate estimates of parameters and their 
standard errors, resulting in misleading power calculations (3, 5). Instead, these guidelines 
recommend focusing on confidence intervals rather than point estimates of effect size (3). Aim 
3 has been expanded to include exploring preliminary responses to the intervention and 
generating initial parameter estimates for sample size calculations. This refinement builds 
upon Aim 3 by incorporating additional aspects aligned with current best practices for 
feasibility studies. Initial parameter estimates for a sample size calculation were calculated to 
detect clinically meaningful differences with adequate power. Outcome measures included a 
pain interference measure (PROMIS Pain Interference Short Form 6b), depression symptoms 
(PHQ-9), anxiety symptoms (GAD-7), and a pain intensity rating. 
 
 
 
 
 
 
 

 
Methods 
Study Design 
This study used a 2-arm, open, feasibility RCT with parallel design. We assessed participants at 
four timepoints, at baseline (T0), 1 month (T1), 3 months (T2) and 6 months (T3) post intervention. 
Inclusion and Exclusion Criteria 
Eligibility criteria included: 1) adult patients (i.e., aged >=18 years) with chronic non-cancer 
related pain (i.e., pain experience was current and present for >=3 months), 2) documentation of at 
least one International Classification of Diseases (ICD) code of a common pain related conditions 
(e.g., low back pain, musculoskeletal pain, fibromyalgia) based on published identified chronic 
pain conditions (6), 3) had at least two primary care visits within the last 12 months at the time of 
recruitment, 4) significant levels of self-reported pain interference (i.e., PROMIS Pain Interference 
Short Form 6b T-score of 55 or above), 5) daily smartphone access, 5) ability to download an app, 6) 
willingness to engage in a 3-month chronic pain self-management program administered via an 
app, 7) speak English, and 8) consent to randomization in the study. 
 
Participants were excluded if: 1) their pain was related to cancer, 2) they had plans for surgery 
within the next 3 months, 3) they were pregnant, or 4) they were receiving hospice services. 
Recruitment and Screening  
Potential participants were identified using electronic health record (EHR) data extracted from 
three health systems, which included information from 60 primary care clinics in Washington and 
Idaho. These data were accessed through the Data QUEST Coordinating Center’s EHR data 
repositories. From the generated potential participant lists, random cohorts were created for 
recruitment email blasts.  
 
  
Patients were invited to participate via direct email. Each email contained a link to an interest 
survey with three options: 1) proceed to the study eligibility survey, 2) request a call back from a 
study coordinator for further discussion, or 3) opt out of the study. Patients who proceeded to the 
eligibility survey were informed at the end of the survey of their study eligibility. Those who were 
eligible were directed to an e-consent form. The e-consent form required patients to either 1) 
confirm that they wanted to participate in the study, 2) request a call to discuss the study with a 
study coordinator first, or 3) confirm that they were not interested in participating in the study. 
Patients who confirmed their interest in participating in the study were asked to sign the e-consent 
form. A study coordinator would then counter-sign the e-consent form. A study coordinator would 
follow up with any call requests and if needed assist with the consent over the phone. 
Group Allocation 
Participants were randomized using a stratified method based on healthcare system and 
age, aiming to distribute them equally across health systems while matching the national age 
distribution of individuals living with chronic pain. This stratified allocation was implemented in the 
REDCap randomization module. The intervention group received access to the 2Morrow Inc. digital 
behavioral health Salty app (2MRx-CP), while the control group received treatment as usual. 
 

 
Upon randomization, the REDCap project was programmed to send automatic emails to 
participants with links to their baseline survey. Participants in both arms needed to complete the 
baseline survey within two weeks to be considered fully enrolled in the study. Participants in the 
intervention arm were emailed separate instructions about how to download and access the app 
and create a user profile. These participants were reminded up to three times (including two 
automatic email reminders and one phone call from a study coordinator) in the two-week 
enrollment window. Those that completed the baseline survey, but did not access the app, are 
included in the study. Participants in the intervention arm that encountered technical difficulties 
with the app were connected with the tech team at 2Morrow, Inc. 
 
Intervention: The Salty Program, 2Morrow, Inc. 
Data collection 
Data was collected at baseline (T0), 1-month (T1), 3-month follow (T2), and at 6-month follow 
up (T3) via REDCap which is a secure, HIPAA-compliant web-based application used for data 
capture and management.  Automatic survey invitation emails were programmed in REDCap to be 
emailed to participants at each study time point. In these automatic emails, participants were 
asked to complete surveys via a personalized REDCap survey link.  They had two weeks to 
complete each survey. During the two-week data collection window, follow-up for participants who 
had not yet completed their surveys could include automatic REDCap email reminders (up to two) 
and a reminder call and/or email from the study team. Participants could return to their surveys 
using their personalized survey link at any time during the data collection window. Time spent 
completing surveys was not recorded. The surveys utilized REDCap enhanced radios and 
checkboxes for a better user experience across different devices (laptops, tablets, and mobile 
phones).  Participants received a $50 e-gift card for each survey they completed, up to $200 total 
for the entire study. REDCap survey settings allowed participants to skip some questions. In 
accordance with IRB requirements, participants were not obligated to answer any questions they 
felt uncomfortable with; as a result, the REDCap survey was configured to allow optional 
responses. For the purposes of statistical analysis, only complete data sets were included for each 
outcome measure. Specifically, if a participant omitted any subscale items necessary to calculate 
a total score, their data were excluded from the summary statistics and analyses for that measure. 
 
The data were extracted from REDCap at the completion of the study for data analyses. No 
identifiers were maintained, and data were stored using a password protected delimited file and 
stored in an access-controlled location on a secure HIPAA-compliant server at UW. 2Morrow gave 
UW usability data logged by their platform. UW linked the 2Morrow usability data to de-identified 
study identifiers, links to identifiers were then destroyed, and stored similarly to the REDCap 
derived data. 
Outcome measures 
(Appendix 1 includes a copy of all outcome measures)  
 
Intervention and Control Group 
 
1. Baseline survey, administered at T0, consisted of demographic questions (education, 
employment, marital status, income and insurance), social determinants of health 
questions (living situation, electricity, food, transportation), and the following tools: 

 
• 
Patient-Reported Outcomes Measurement Information System (PROMIS) Pain 
Interference Scale – Short Form 6b is a six-item self-report questionnaire that 
assesses the impact of pain on various aspects of a person’s life (e.g., social, cognitive, 
emotional, physical and recreational activities) over the last 7 days (7). Responses are 
scored using a 5-point ordinal rating scale from 1 to 5 (1=Not at all, 2=A little bit, 
3=Somewhat, 4=Quite a bit, 5=Very much). Raw score totals are converted to T-score 
using the scoring manual (8). T-score of 50 is the mean for the U.S. general population 
with a standard deviation of 10; the higher the T-score, the worse the pain interference.  
• 
Patient Health Questionnaire – 9 (PHQ-9) is a 10-item self-report questionnaire used 
to assess depression symptoms consistent with criteria for Major Depressive Disorder 
over the last two weeks (9) . The tool uses a 4-point rating scale (0=not at all, 1=several 
days, 2=more than half the days, 3=nearly every day) and has demonstrated strong 
psychometric properties including high levels of specificity and sensitivity of major 
depressive disorders (9, 10).  
• 
Generalized Anxiety Disorder 7-item scale (GAD-7) is a widely used self-reported 
questionnaire to measure the severity of generalized anxiety disorder symptoms over 
the past two weeks (11). Responses are scored from 0 to 3 (0= Not at all, 1= Several 
days, 2= More than half days, 4= Nearly every day). The tool has shown strong 
psychometric properties, including high evidence of internal consistency and reliability 
(12).   
• 
An additional set of 4 questions explored participants’ recent primary care visits, 
engagement with the Salty app, and receipt of treatment for their pain in the last month. 
2. Follow-up survey, administered at T1, T2, and T3, consisted of the following tools: PROMIS 
pain interference, PHQ-9, and GAD-7, and pain intensity. 
3. The Health Care Utilization (HCRU) (Administered at T2 and T3). 
 
Intervention Group 
1. mHealth App Usability Questionnaire (MAUQ), administered at T2, is a 21-item survey 
that assesses mobile health (mHealth) app usability across three domains: ease of use and 
satisfaction (8 items), system information arrangement (6 items), and usefulness (7 items). 
It uses a 7-point Likert-type scale (1=strongly disagree to 7=strongly agree) and has 
established reliability and validity evidence (13).   
2. Salty Program for Chronic Pain Questionnaire (SaltyChP) is a 6-item survey developed by 
2Morrow, Inc., that explores specific aspects of the app (e.g., patients’ satisfaction with 
various specific app features, patient ratings of helpfulness of the app for pain, likelihood to 
recommend the app to others) using Likert-type response scales. The survey includes two 
open-ended questions addressing what was helpful and what could be improved in the 
app. This survey was administered at both T2 and T3.  
 
 

 
References  
 
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Teresi JA, Yu X, Stewart AL, Hays RD. Guidelines for Designing and Evaluating Feasibility 
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Appendixes 
Appendix 1. Outcome measures 
Eligibility Survey 
 
 
 

 
 
 

 
 

 
Baseline Survey (T0) 
 
 

 
 
 
 
 

 
 
 
 

 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
1-Month, 3-Month and 6-Month Follow-up Survey 
Includes the Salty for Chronic Pain Questionnaire for Intervention Arm 
 
 
 

 
 
 

 
 
 

 
 
 

 
 
 

 
Health Care Resource Utilization (HCRU) Survey 
 
 

 
mHealth App Usability Questionnaire