Rage Against the Pain: An Alternative Yoga Program to Address Chronic Low Back Pain Among Veterans
Phase: NA
Conditions: Chronic Low Back Pain
Sponsor: VA Office of Research and Development

 
 
Rage Against the Pain: An Alternative Yoga Program to Address Chronic Low Back Pain Among 
Veterans (PPO 19-362; NCT05103475) 
 
PROTOCOL 
 
12/15/2022 
 
 
 

 
 
RESEARCH DESIGN/METHODS 
 
Design Overview. This mixed-methods pilot intervention study will employ pre-and- post-intervention data 
collection (see Figure 2 below).   
 
Design/Setting. All research activities will take place at the Hines VA Hospital located in the Chicagoland 
area. Yoga classes will be offered through the Recreation Therapy Service at Hines, in the dedicated space 
where currently offered yoga classes are held. Survey data collection activities will be completed via 
mail/phone or in person (per the Veterans’ preference), and semi-structured interviews will be completed via 
phone.  
 
Sample. Our sample will be comprised of Veterans who receive primary care services at Hines and 
experience chronic low back pain. We will identify Veterans who, in the prior 3 months, received a diagnosis 
associated with chronic low back pain (e.g., ICD10 codes associated with back pain and low back pain 
extracted from VA administrative records (the CDW)). As needed, we may also identify eligible individuals via 
provider referral and/or snowball sampling (i.e., peer referral), as described below.  
 
Recruitment. We will mail recruitment materials to individuals identified as eligible based on ICD10 codes 
inviting them to participate in a VA research study aimed at helping Veterans who experience chronic low 
back pain. We will require real SSN access to pull Veteran demographic, health and contact information for 
recruitment efforts. Patients will receive a recruitment letter and flier in the mail and will be asked to contact 
our study team if they are interested in participating. As needed, we may also place follow-up telephone calls 
to Veterans who do not contact us. If needed, we will also employ the following recruitment strategies: we will 
post fliers in primary care and pain clinic waiting areas; we will ask providers working in primary care and pain 
clinics to refer eligible Veterans to the study; we will have our project coordinator recruit in person in pain 
clinic waiting areas; we will ask Veterans who enrolled and participated in early classes to refer their peers to 
the study (i.e., snowball sampling). Veterans who are interested will contact our project manager, who will 
screen them for eligibility based on the inclusion criteria detailed below using a screening form. If we receive 
responses from primarily women Veterans early in our recruitment efforts, we will target later recruitment 
efforts to male Veterans to ensure that both male and female Veterans are represented in the study.  
 
Randomization. Eligible patients will be randomly assigned to RAP or treatment as usual (regular yoga 
routinely offered at the hospital, which at our facility is Hatha yoga) using a random number generator.  
 
Intervention Details. Both the RAP and Hatha yoga classes will be offered once a week for 12 weeks; this 
‘dose’ of yoga has been found to be effective in a previous randomized controlled trial (RCT) focused on yoga 
participation among individuals with back pain.1 Classes will be about 60 minutes long. To accommodate 
targeted class sizes, we will run two cohorts, either concurrently (on different days of the week) or in waves 
(one session held after the first is completed) if needed. Yoga mats, straps and sets of blocks will be 
available for participants to use.  
During the beginning months of the study we will hold a series of meetings with our yoga teachers, 
research team and advisory panel members, to finalize the curriculum, music play-lists and scheduling (day 
of the week and time of the day) of the classes; however, yoga poses that are known to benefit individuals 
who experience chronic low back pain will comprise the poses used in each program. These poses already 
comprise much of Hatha yoga classes, and we do not anticipate that finalizing the curriculum for either 
program will be significantly time-intensive.   
 
Participating in the Rage Against the Pain and treatment as usual (Hatha yoga) interventions will 
entail following along with the yoga poses and corresponding breath work (e.g., suggestions for when to 
inhale and exhale commensurate with the movement) being cued by the instructor. Veterans will be clearly 
cued about options for modification for every pose, including options to modify poses using a chair or the 
wall; Veterans who are unable to engage in a modified version of any pose will be instructed to take child’s 
pose or rest in a chair, against the wall or on the floor during that pose. When the set of movements for each 
class has been run through, the class will engage in a culminating activity (meditation referred to savasana or 

 
 
or cool down, see below) wherein Veterans will be instructed to sit in chairs or lay on the floor with their eyes 
closed to relax. Veterans will be asked to complete practice logs in class. 
We will also share a training manual with our Veteran participants (along with a yoga mat, strap and 
set of blocks) and encourage them to engage in home practice (ideally, about half an hour three times per 
week in addition to the weekly group classes).2  
     Treatment as Usual. The ‘treatment as usual’ class will be conducted in the style of the yoga classes 
currently being offered to Veterans at the Hines VA Hospital, which is a program akin to Hatha yoga with 
chair modifications available to all Veterans who choose/need to use them (described above).  
     Rage Against the Pain. The RAP program curriculum will mirror that of the Hatha Yoga classes, but will 
differ from this traditional yoga practice in a number of ways: (1) the classes will be set to rock/heavy metal 
music; (2) meditation will not be incorporated; (3) yoga terms will not be used to describe the 
poses/movements (rather, poses will be cued in plain descriptive English terms); (4) the culminating activity 
for the class will be called a ‘cool down’ (rather than the typical relaxation/meditation exercise used in yoga, 
referred to as savasana).  
 
Possible Risks or Discomforts. Any procedure has possible risks and discomforts. The procedures in this 
study may cause all, some, or none of the following risks or side effects: participating in the Rage Against the 
Pain High Intensity Stretching or Hatha Yoga classes may cause muscle soreness, pain, fatigue, injury, 
and/or emotional discomfort; participating surveys/semi-structured interviews may lead to discomfort with 
answering certain questions (Veterans will be informed that they do not have to answer any question(s) that 
make them feel uncomfortable). The recreation therapists running the intervention classes are trained and will 
make sure the class activities can be modified to make sure everyone can participate safely. Participants will 
be encouraged to participate at their own ability and not push past their limits. Our instructors are seasoned 
VA recreation therapists and have experience with working with Veterans who experience pain. 
There is also a small risk of breach of confidentiality. We will take every possible step to protect the 
privacy of the study information, such as using a study ID rather than participant names for all data collection 
(surveys and interviews) and making sure research data are secure and computer files are password 
protected.   
Risks of the usual care are not risks of the research. Those risks are not detailed in this protocol. 
During the consenting process, participants will be asked to talk with their health care providers if they have 
any questions about the risks of usual care. Participation in research may involve a loss of privacy. All 
research records will be kept as confidential as possible. 
To mitigate any potential risks or discomforts, we have developed a comprehensive safety plan 
(please see below).  
 
Safety Considerations. We recognize that safety must be an utmost concern in developing and testing the 
RAP program. As such, we consulted with others in VA on how best to design the safety plan for this 
proposal, to ensure that no relevant facets were overlooked. We have incorporated safety considerations into 
every aspect of the program to ensure the well-being of those Veterans who choose to adopt/participate. This 
comprehensive strategy is based on established best practices from other recent studies examining the 
impact of yoga on pain in Veterans with low back pain.3 We will also work with our yoga teachers and 
advisory panel members (including a physical therapist (PT)) to ensure that program curriculum is well-
designed and focused on safety considerations. Our safety plan is described in detail below.  
     Inclusion Criteria. Veterans will be eligible to participate in the study if they: (1) currently receive primary 
care services at the Hines VA, and (2) received a diagnosis associated with chronic low back pain in the 
previous 3 months as identified through the CDW using relevant ICD-10 codes and a screening 
questionnaire, as appropriate 
     Exclusion Criteria. Veterans will be ineligible to participate in the study if any of the following are true for 
them: (1) they currently regularly participate in yoga; (2) they regularly participated in yoga in the previous 6 
months; (3) their back pain is a symptom of a specific treatable or underlying disease/condition(s) (e.g., 
ankylosing spondylitis, active or recent malignancy, fracture/spinal cord injury, spinal infection); (4) they are 
experiencing progressive neurological deficits; (5) they have any other condition which results in severe 
disability (e.g., non-ambulatory, hemiparesis, severe cognitive deficits); (6) they have a diagnosis associated 
with psychosis; (7) they are currently experiencing issues around substance abuse (not including prescription 
opioids), as identified through ICD-10 codes associated with ‘mental and behavioral disorders due to 

 
 
psychoactive substance use’ recorded in the patient’s medical record in the previous 3 months (which will be 
extracted from the CDW); (8) they do not plan to be living in the Chicagoland area for the duration of the 
study. These exclusion criteria are based on the criteria used by Saper et al.4 in their RCT of yoga for 
Veterans with chronic low back pain. In addition, women Veterans who are pregnant at the time of screening 
will not be enrolled in the study. 
     Pre-Enrollment Screening. Currently, the yoga programs offered at the Hines VA do not require that 
Veterans are cleared by their health care providers before they participate. Rather, the yoga instructor 
reviews the medical record of each Veteran before they can enroll in the yoga class to make sure that 
individual is not contraindicated from participating. However, other programs that might be considered more 
‘risky’ (e.g., therapeutic horseback riding) do require that the patient receives medical clearance before they 
are able to enroll/participate. Because this is a research study, out of an abundance of caution, we will 
require that all Veterans are cleared by their Hines primary care provider before we allow them to enroll in the 
study. That is, when a Veteran contacts our research project manager and expresses interest in participating, 
our project manager will contact their primary care provider at Hines, explain what participation would entail 
and what are our inclusion and exclusion criteria are, and ask the provider to endorse that patient’s 
participation or let us know that they do not believe the Veteran to be a candidate for participation. In addition, 
as she is available, the PT on our advisory panel will complete in-person PT balance screens (as needed) 
with Veterans who are interested. The instructors will conduct chart reviews for any concerns or 
contraindications to participating in weekly classes.  
     Class Size. We will run two 12-week sessions of each respective yoga program. We will enroll 8-10 
Veterans in each to ensure the yoga instructor can pay adequate attention to each participant and assist with 
modifications/pose adjustments as needed and appropriate.  
     Multiple Clinicians in the Room. As scheduling allows, the PT on our team will attend yoga classes. This 
will allow for extra clinical coverage to help Veteran participants modify poses as needed and monitor 
participants to ensure they are participating safely.  
     Pose Modifications. Yoga instructors will cue options for modification of each pose. Veterans will be 
encouraged to participate at their own ability and not push past their limits. Our yoga instructors are 
seasoned VA recreation therapists, and have experience working with Veterans who experience pain. 
     Monitoring Adverse Events. We will meticulously monitor adverse events. Adverse events will be tracked 
in a number of ways: (1) all participants will be encouraged to discuss any impacts they believe program 
participation may be having on their health with the yoga instructors either before or after class each week – 
we will ask both the participants and yoga instructors to report this information to the study project manager, 
(2) we will include a question on the post-program follow-up survey to assess any perceived impacts of 
participation on Veterans’ health, and (3) among Veterans who do not complete the follow-up survey or leave 
this question blank, the study project manager and/or PI will conduct a thorough chart review to rule out 
notation of possible study-related adverse events in the patient’s medical record.  
     Right of the Investigator to Terminate Participation. We have the right to terminate a Veteran’s 
participation, without regard to their wishes, in the research study if any of the following occur: (1) they 
become uncooperative or unwilling to complete study-related tasks; (2) they are experiencing undue stress 
from the study procedures; (3) they are experiencing undue physical strain from the study procedures (e.g., 
the exertion required is too great for them, participation is causing them excessive pain, etc.); (4) they have a 
substance abuse, mental health, and/or medical problem that interferes with completion of the study-related 
tasks; (5) they behave inappropriately in a session or while completing a study-related task; (6) the study is 
stopped by the sponsor, which is the VA Office of Research Development. 
     Follow-Up Care. If a Veteran experience injuries from their participation in this research project, we will 
either (1) get their permission to contact your Hines primary care provider and suggest that they follow up 
with the Veteran, or (2) escort the Veteran to the Hines Emergency Department, contact the Hines rapid 
response team (if you are within the area of their purview), or call 911. We will not be doing follow-up care 
with individuals who choose to withdraw from the study. 
 
Enrollment and Sample Size. As mentioned above, we will aim to enroll 16-20 Veterans in RAP and another 
16-20 Veterans in the Hatha yoga program, for a total recruitment target of 32-40 Veterans. Looking back 3 
months, we estimate that there are approximately 1,500 Veterans at Hines who meet our study eligibility 
criteria. Accordingly, we do not anticipate having any difficulties identifying and enrolling enough patients to 
meet this target. However, if needed we will expand our time-frame to include Veterans who received the 

 
 
relevant diagnoses in the previous 6, 9 or 12 months. Of note, goals for aims 2 and 3 include determining 
feasibility numbers for recruitment and estimates of effect sizes to inform power considerations for the next 
step, the larger trial.  
 
Data Collection. Our data collection instruments reflect the factors that influence behavior as outlined in our 
conceptual framework; the relevant factors are noted in italics next to relevant questions in the appendices. 
Outcomes and strategies for measuring each are described below and summarized in Table 1.  
     Pre- and Post- Program Participation Surveys. All Veterans who are enrolled into the study will receive a 
pre-participation survey (Appendix D) approximately 1 week before the RAP/Hatha yoga classes begin, and a 
post-participation survey approximately 1 week after the 12-week programs are finished (Appendix E). 
Surveys will be mailed to Veterans so that persons who do not attend the first class of the program they are 
randomized to or do not complete 
the program still have the 
opportunity to fill out a survey. This 
will allow us to also compare 
outcomes between individuals who 
did and did not complete the 
programs. Veterans will also be 
given the option to complete the 
surveys over the phone with the 
study project manager, and we will 
follow up with Veterans who do not 
return a mailed survey by phone to 
optimize response rates. We will also provide Veteran to complete the baseline survey in-person at the time 
of study enrollment. Veterans who attend the first and last yoga class of each session will also be provided an 
opportunity to complete the survey in person at their preference. Veterans will receive $25.00 in appreciation 
of their time for each returned survey (up to two total surveys). Of note, we will not provide any token 
incentives for completing the yoga programs because we do not want to contaminate adoption rate data such 
that we cannot tease out whether Veterans are participating because they like the program or because they 
want to complete the program so that they can earn the incentive.  
     The surveys will include measures of pain intensity; pain behavior; function; quality of life (QOL); sleep; 
depression; stress; medication (and other pain reduction strategy) use, and; patient perceptions of and 
experiences with the program.  
     Pain intensity will be measured using the Defense and Veterans Pain Rating Scale,5 a valid and reliable 
numeric rating scale that asks individuals to report the average intensity of their low back pain on a scale of 0 
(no pain) to 10 (worst pain imaginable)6 for the previous 7 days.  
     Pain interference (how much the individual’s pain has interfered with all aspects of their life in the prior 7 
days) will be measured using the validated, reliable Patient-Reported Outcomes Measurement Information 
System (PROMIS) 8-item pain interference short form.7 PROMIS scores are standardized to reflect the 
general adult US population, such that a mean score of 50 reflects average pain experience; higher scored 
indicate greater levels of pain interference. 
     Back pain-related function will be measured using the Roland-Morris Disability Questionnaire (RMDQ), a 
valid and reliable scale of physical disability resulting from chronic low back pain.8 The RMDQ asks 
individuals to read 24 items noting back pain-related functional impairments and mark those that describe 
them. All marked items are summed for a total score ranging from 0 (no impairment) to 24 (maximum 
impairment). A 30% reduction in score from baseline coupled with an improved self-reported pain intensity 
rating is considered a clinically significant impact.9  
     Health-related QOL will be measured using the Medical Outcomes Study 12-Item Short Form Health 
Survey (SF-12),10 a valid and reliable measure that produces physical and mental health sub-scale scores.  
     Sleep will be measured using the Insomnia Severity Index, which is a valid and reliable 7-item scale that 
produces a composite score of an individual’s level of sleep disturbance during the past 14 days.11 Item 
responses are added to obtain a total scale score; greater scores indicate more disturbed sleep and cut-
points are provided by the scale developers that map to levels of clinical severity of sleep disturbance.  
     Depression severity will be measured using the 8-item Patient Health Questionnaire (PHQ-8), a valid and 
reliable measure that assesses individual’s depression severity by asking them to evaluate 8 items that 

 
 
reflect symptoms of depression and indicate how often they have experienced each in the prior two weeks on 
a scale of 0 to 3 (not at all - nearly every day).12 Scores range from 0 (no depression symptomology) to 24 
(most severe symptomology); scores can also be classified into mild, moderate, moderately severe and 
severe categories using cut-scores defined by the scale developers. 
     Stress will be measured using the Perceived Stress Scale (PSS) – 4 Item, a valid and reliable measure of 
individual’s perceptions of how stressful their life experiences are.13 The PSS is comprised of 4 questions and 
produces a composite score of perceived stress (higher scores indicate higher perceptions of stress). 
     We will ask participants to self-report any pain medication use (e.g., opiates, muscle relaxants, NSAIDs) in 
the pre- and post-participation surveys. Medication use will be corroborated through brief, targeted chart 
reviews, which reflects the process used by Groessl et al.3 to collect information about pain medication use 
for their RCT of yoga for low back pain among Veterans. We will also ask participants to report any use of 
other programs for pain management (e.g., acupuncture, massage, mindfulness/meditation, cognitive-
behavioral therapy) on both the pre- and post-participation surveys. This information will also be corroborated 
through brief, targeted chart reviews. The surveys will also include some basic questions (that map to our 
conceptual model) about patient’s perceptions of and experiences with the program (extent to which they 
liked it, would participate again, would recommend to a peer, felt it impacted their health and how); these 
topics will be assessed in-depth via the post-participation semi-structured interview. 
     Program Initiation and Participation. The primary focus of this study is the reach and sustained 
engagement of the RAP program, which we hypothesize will be greater compared to traditional (Hatha) yoga. 
Program initiation (e.g., reach) will be defined as the number of individuals who start the RAP or Hatha yoga 
programs after being screened, deemed eligible for participation, and randomized to one or the other. 
Program participation (e.g., sustained engagement) will be defined as the average number of classes 
Veterans attended for each respective program, and the number of Veterans who attended the majority 
(9/12) of classes. These outcomes will be tracked via self-report (on the post-participation survey) and in real-
time by asking Veterans to sign in before each class they participate in. In addition, we will ask any Veteran 
who contacts us indicating interest but ultimately chooses to not enroll in the study before they are 
enrolled/randomized why they are choosing not to participate.  
     Post-Participation Interviews with Veterans (Appendix F). To gather in-depth data about Veterans’ 
perceptions of and experiences with the RAP and Hatha yoga programs, we will invite Veterans who 
completed the majority (e.g., 9 of 12) of program sessions to participate in a semi-structured interview. We 
will also conduct interviews with a sample of Veterans who did not complete a majority of sessions of either 
program, to ascertain why they stopped participating. We will conduct interviews with all Veterans who wish 
to complete an interview, for a total of up to 40 interviews. Interview participants will receive $30 in 
appreciation of their time. Our interview questions will reflect the factors detailed in our theoretical framework. 
Examples of questions include: did you like participating in the [RAP/Hatha yoga] program; did you talk about 
participating in the [RAP/Hatha yoga] program with your peers? what about your family members or 
significant other?; was there anything that made it difficult for you to participate?; was there anything that 
could have increased your interest/commitment to completing the program?; do you feel that participating in 
the [RAP/Hatha yoga] program impacted your back pain?; what about other things that could be related to 
your back pain, like your mood or sleep? A hallmark of qualitative research is its flexibility;14 thus, further 
questions may arise depending on participants’ responses, enabling us to probe into related domains. 
Interviews will last approximately 30 minutes and will be audio-recorded and transcribed verbatim for 
analysis. We will obtain verbal consent using a consent script before conducting the interview. 
 
Costs to Participants and Payment.  
 
Costs to Participants. A Veteran subject will not be required to pay for medical care and services 
received as a subject in an approved VA research study. Some Veterans are required to pay a co-payment 
for the care they receive. These requirements will continue to apply to medical care and services provided by 
the VA that are not part of this research study.  
Summary of Payment Offered for Participation. Payments will be provided through a voucher that can 
be redeemed for cash at the Agent Cashier or by direct deposit. As noted above, Veterans will receive: (1) 
$25 for each survey that they complete and return for this study (up to $50 total if they return both surveys); 
(2) if they are asked participate in an interview, they will receive $30 upon completion of that interview. 
Therefore, if a Veteran returns both surveys and completes an interview, they may receive up to $80 total 

 
 
throughout their participation in this study. These payments will not be pro-rated if a Veteran withdraws from 
the study or if their participation is terminated before the study is over. 
 
Data Analyses. 
     Quantitative Analysis of Surveys. We will use descriptive statistics (proportions, means) to assess 
adoption, sustained engagement, and pain and related outcomes. All outcomes will be scored based on the 
guidelines of each respective measure. Rates of adoption (e.g., program initiation, defined as the number of 
Veterans who start the RAP or Hatha yoga programs after being screened, deemed eligible for participation, 
and randomized to one or the other) and sustained engagement (e.g., participation, defined as the average 
number of classes Veterans attended for each respective program, and the number of Veterans who 
attended the majority (9/12) of classes), will be compared for the RAP and traditional yoga groups using 
bivariate analyses (t-tests, chi-square tests) , to determine if initiation and participation rates are statistically 
significantly higher for the RAP vs. Hatha yoga groups (Hypothesis 1) . We will use bivariate analyses (t-
tests) and ANOVA to compare outcomes (pain intensity; pain behavior; function; QOL; sleep; depression; 
stress; medication (and other pain reduction strategy) use) (1) for each Veteran before and after program 
participation, and (2) between Veterans in the RAP vs. traditional yoga programs. We will also compare all 
outcomes by gender. We will calculate effect sized for all bivariate comparisons. As mentioned above, our 
goals for aims 2 and 3 include determining feasibility numbers for recruitment and estimates of effect sizes to 
inform power considerations for the next step, the larger trial. We will use our adoption and participation rates 
to base recruitment and enrollment targets for that trial, and will base power calculations off of the effect sizes 
on key outcomes (e.g., pain intensity, interference, back-pain related function) observed in this pilot. Survey 
data on patient experiences with and perceptions of the programs, assessed in part via open-ended 
questions on the post-program participation survey, will be content coded by Dr. Etingen and the qualitative 
research specialist and triangulated with interview data under the guidance of Dr. Hogan (please see below).  
     Qualitative Analysis of Semi-Structured Interviews. Audio-recordings of the post-participation semi-
structured interviews will be transcribed verbatim. Qualitative analysis software will be used to support 
analyses. Our qualitative analysis approach will be both deductive and inductive.15 We will develop an initial 
code list a priori that reflects categories of interest, based on elements of our conceptual model (e.g., 
Veterans’ attitudes toward participating in yoga, their perceived subjective norms and behavioral control, and 
their behavioral intention). Within each category, we will inductively develop additional codes and analyze the 
text for themes and patterns. This will be an iterative process where our code list may be revised to account 
for novel instances in the data. We will continue until saturation14 is reached across categories. Established 
qualitative analytic techniques will be used throughout this process, including the constant comparative 
method, which involves identifying key themes and concepts emergent from the data to generate meaningful 
categorization.14 
     We will leverage a team-based approach to qualitative analysis drawing on the breadth of expertise of our 
team. Dr. Etingen and the qualitative research specialist will first independently review and open-code 3-5 
transcripts to identify prominent themes. They will then convene a series of meetings to compare their codes, 
develop a set of analytic categories agreed upon through discussion, and develop the initial code list. They 
will continue with the next set of transcripts to develop new codes and revise codes applied to all prior 
transcripts, until they reach saturation with codes and themes, and finalize a codebook. Dr. Etingen and the 
qualitative research specialist will then code un-coded transcripts until they reach inter-coder reliability 
greater than >0.90%.16 The iterative, collaborative nature of this process will maximize the validity and overall 
soundness of our analysis. 
 
Limitations. We recognize that because we are proposing to carry out the study activities at one VA facility, 
cultural idiosyncrasies may impact the generalizability of our results to other VA facilities. In addition, while 
we know that yoga is under-utilized, particularly by male Veterans, we do not know what proportion of 
Veterans that could benefit from yoga participation choose not to participate because they have a negative 
perception of it. Because of this, we cannot say for certain how many Veterans might benefit from the 
alternative program we are proposing, though we anticipate it will be a significant number based on 
postulations in recent literature17 and feedback from Veterans (described above).   
 
 
 
 

 
 
REFERENCES  
 
1. Saper RB, Boah AR, Keosaian J, Cerrada C, Weinberg J, Sherman KJ. Comparing once- versus twice-
weekly yoga classes for chronic low back pain in predominantly low income minorities: a randomized dosing 
trial. Evid Based Complement Alternat Med. 2013;2013:658030. doi: 10.1155/2013/658030. 
 
2. Saper RB, Lemaster C, Delitto A, et al. Yoga, physical therapy, or education for chronic low back pain: a 
randomized noninferiority trial. Ann Intern Med. 2017;167(2):85-94. doi: 10.7326/M16-2579. 
 
3. Groessl EJ, Liu L, Chang DG, et al. Yoga for military Veterans with chronic low back pain: a randomized 
clinical trial. Am J Prev Med. 2017;53(5):599-608. doi: 10.1016/j.amepre.2017.05.019. 
 
4. Saper RB, Lemaster CM, Elwy AR, et al. Yoga versus education for Veterans with chronic low back pain: 
study protocol for a randomized controlled trial. Trials. 2016;17(1):224. doi: 10.1186/s13063-016-1321-5. 
 
5. Nassif TH, Hull A, Holliday SB, Sullivan P, Sandbrink F. Concurrent validity of the Defense and Veterans 
Pain Rating Scale in VA outpatients. Pain Med. 2015;16(11):2152-61. doi: 10.1111/pme.12866. 
 
6. Buckenmaier CC 3rd, Galloway KT, Polomano RC, McDuffie M, Kwon N, Gallagher RM. Preliminary 
validation of the Defense and Veterans Pain Rating Scale (DVPRS) in a military population. Pain Med. 
2013;14(1):110-23. doi: 10.1111/j.1526-4637.2012.01516.x. 
 
7. Cella D, Riley W, Stone A, et al. The Patient-Reported Outcomes Measurement Information System 
(PROMIS) developed and tested its first wave of adult self-reported health outcome item banks: 2005-2008. J 
Clin Epidemiol. 2010;63(11):1179-94. doi: 10.1016/j.jclinepi.2010.04.011.  
 
8. Roland M, Fairbank J. The Roland-Morris Disability Questionnaire and the Oswestry Disability 
Questionnaire. Spine (Phila Pa 1976). 2000;25(24):3115-24. PMID: 11124727. 
 
9. Jordan K, Dunn KM, Lewis M, Croft P. A minimal clinically important difference was derived for the Roland-
Morris Disability Questionnaire for low back pain. J Clin Epidemiol. 2006;59(1):45-52. doi: 
10.1016/j.jclinepi.2005.03.018 
 
10. Ware J Jr, Kosinski M, Keller SD. A 12-Item Short-Form Health Survey: construction of scales and 
preliminary tests of reliability and validity. Med Care. 1996;34(3):220-33. PMID: 8628042 
 
11. Morin CM, Belleville G, Bélanger L, Ivers H. The Insomnia Severity Index: psychometric indicators to 
detect insomnia cases and evaluate treatment response. Sleep. 2011;34(5):601-8. doi: 
10.1093/sleep/34.5.601.  
 
12. Kroenke K, Strine TW, Spitzer RL, Williams JB, Berry JT, Mokdad AH. The PHQ-8 as a measure of 
current depression in the general population. J Affect Disord. 2009;114(1-3):163-73. doi: 
10.1016/j.jad.2008.06.026.  
 
13. Cohen S, Kamarck T, Mermelstein R. A global measure of perceived stress. J Health Soc Behav. 
1983;24(4):385-96. PMID: 6668417 
 
14. Strauss A, Corbin J. Basics of Qualitative Research: Techniques and Procedures for Developing 
Grounded Theory. Thousand Oaks, CA: Sage; 1998. 
 
15. Bradley EH, Curry LA, Devers KJ. Qualitative data analysis for health services research: developing 
taxonomy, themes, and theory. Health Serv Res. 2007;42(4):1758-72. doi: 10.1111/j.1475-
6773.2006.00684.x 
 

 
 
16. Tinsley HEA, Weiss DJ. Interrater reliability and agreement of subjective judgements. J Couns Psychol. 
1975;22(4):358-76. doi: 10.1037/h0076640.