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Abstract
Introduction Opioid tapering after surgery is recommended among patients with chronic opioid use, but it is unclear how this process affects their quality of life. The objective of this study was to evaluate how opioid tapering following surgery was associated with patient-reported outcome measures related to pain control and behavioral changes that affect quality of life.
Methods We conducted an explanatory sequential mixed-methods study at a VA Medical Center among patients with chronic opioid use who underwent a spectrum of orthopedic, vascular, thoracic, urology, otolaryngology, and general surgery procedures between 2018 and 2020. Patients were stratified based on the extent that opioid tapering was successful (complete, partial, and no-taper) by 90 days after surgery, followed by qualitative interviews of 10 patients in each taper group. Longitudinal patient-reported outcome measures related to pain intensity, interference, and catastrophizing were compared using Kruskal Wallis tests over the 90-day period after surgery. Qualitative interviews were conducted among patients in each taper group to identify themes associated with the impact of opioid tapering after surgery on quality of life.
Results We identified 211 patients with chronic opioid use (92% male, median age 66 years) who underwent surgery during the time period, including 42 (20%) individuals with complete tapering, 48 (23%) patients with partial tapering, and 121 (57%) patients with no taper of opioids following surgery. Patients who did not taper were more likely to have a history of opioid use disorder (10%—partial, 2%—complete vs 17%—no taper, p<0.05) and be discharged on a higher median morphine equivalent daily dose (52—partial, 30—complete vs 60—no taper; p<0.05) than patients in the partial and complete taper groups. Pain interference (−7.2—partial taper and −9.8—complete taper vs −3.5—no taper) and pain catastrophizing (−21.4—partial taper and −16.5—complete taper vs −1.7—no taper) scores for partial and complete taper groups were significantly improved at 90 days relative to baseline when compared with patients in the no-taper group (p<0.05 for both comparisons), while pain intensity was similar between groups. Finally, patients achieving complete and partial opioid tapering were more likely to report improvements in activity, mood, thinking, and sleep following surgery as compared with patients who failed to taper.
Conclusions Partial and complete opioid tapering within 90 days after surgery among patients with chronic opioid use was associated with improved patient-reported measures of pain control as well as behaviors that impact a patient’s quality of life.
- Acute Pain
- Pain Management
- Opioid-Related Disorders
- Analgesics, Opioid
- Outcome Assessment, Health Care
Data availability statement
Data are available on reasonable request.
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WHAT IS ALREADY KNOWN ON THIS TOPIC
Prior studies suggest that partial or complete opioid tapering among chronic opioid users may have a negative impact on mental health and quality of life.
WHAT THIS STUDY ADDS
The results of this study show that the ability of Veterans with chronic opioid use (COU) to taper their opioid requirements after surgery is associated with significant improvements in patient-reported pain control and quality of life. Many negative health effects associated with COU are not found in Veterans within 90 days after surgery when their opioid use has been significantly reduced.
HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY
The findings from this study support patient-centered clinical strategies and policies designed to taper chronic opioid user patients off opioids within 90 days after surgery when feasible to achieve positive health benefits.
Introduction
Chronic opioid use (COU) is very common among patients who present for evaluation and management of surgical care throughout the USA. It has been estimated that up to 30% of patients undergoing a wide spectrum of major surgery have been taking opioids regularly for at least 90 days before their procedure.1–4 Among patients undergoing inpatient surgery in the Veterans Health Administration (VHA), a recent study shows that 20% are chronic opioid users while another 28% of Veterans report intermittent use of opioids before surgery.5 Preoperative opioid use among this population has been shown to be the strongest predictor of persistent long-term postoperative use and associated complications.4 6 This includes a spectrum of opioid-related adverse health effects that may include declines in activity, mood, energy, and sleep patterns.7
There are a number of different strategies that have been employed to help COU patients taper opioids after surgery and consequentially reduce the risk of developing opioid use disorder and associative negative health effects.8 This includes delivering directed perioperative education, cognitive behavioral therapy, and individualized tapering plans through both in-person and telemedicine-based approaches to help ensure that patients reduce their dependence on opioids during the postoperative period.9 10 Some work has suggested that non-consensual opioid tapering among COU patients not undergoing surgery may lead to increased rates of overdose, withdrawal, and mental health crisis.11 But another recent study from our group showed that complete opioid tapering after surgery is able to be accomplished without increased risk of adverse pain outcomes.12 As such, there is some debate whether consensual patient-centered opioid tapering strategies employed in the perioperative and postoperative period may have unintended consequence that could negatively impact quality of life (QOL).
It is important to examine the effects of decreasing opioid use by different degrees after surgery among COU patients and determine whether tapering strategies have any negative associations with patient’s pain control or QOL. The purpose of this sequential mixed-methods study was to compare changes in patient-reported outcome measures (PROMs) among patients based on the degree that opioid tapering was successfully after surgery, and then interview patients to explore whether the ability to taper had any significant effect on behaviors known to impact a patient’s QOL.
Methods
Study design and patient population
An explanatory sequential mixed-methods study was designed to examine the effects of opioid tapering among patients with a history of COU prior to undergoing a major surgery. First, patients identified with a history of COU that presented to the Salt Lake City Veterans Administration Health Center (SLC-VAHC) for elective orthopedic, vascular, thoracic, urology, otolaryngology, and general surgery between January 2018 and December 2020 were enrolled into a perioperative medical home known as the transitional pain service (TPS). Patients were excluded from analysis if they did not have a history of COU prior to surgery, died within 90 days of surgery, or had an additional surgery within 90 days of the index surgery (figure 1). As previously defined, patients were designated as COU if they had a prescription for opioids of any dose for 60 continuous days prior to surgery or if they had filled three or more prescriptions of at least 28 days duration within 180 days prior to surgery.13 14 Second, patients were recruited for qualitative interviews based on their degree of opioid tapering at 90 days after surgery (figure 1). A quota sampling method was used to select patients and caregivers for interviews, and enrolment was continued until the sample size was sufficient to achieve thematic saturation. We used a constructionist grounded theory framework to qualitative analysis to determine the impact of tapering on patient’s health behavior and QOL. Finally, this manuscript was prepared in adherence with the Strengthening the Reporting of Observational Studies in Epidemiology and Standards for Reporting Qualitative Research reporting guidelines.
Flow diagram of cohort selection for sequential mixed-methods analysis of patients with partial, completer and no-tapering after surgery. COU, chronic opioid use; VAMC, veterans administration medical center.
TPS program
The SLC-VAHC TPS is a program that promotes multimodal pain treatment strategies for surgical pain and opioid tapering during the postoperative period that incorporates enhanced recovery after surgery protocols.10 14 Briefly, patients on chronic opioid therapy were enrolled into TPS prior to surgery during which time they interacted with TPS nurses, psychologists, and clinicians to receive education about surgical recovery and expectations for pain management and an individualized pain plan developed for them. The TPS team followed them during their in-hospital surgical stay and then at scheduled follow-up intervals (2, 7, 14, 21, 30, 60, and 90 days after hospital discharge) for at least 6 months after surgery to help provide recommendations for pain management as well as education and support for opioid tapering. All opioid tapering was done with patient oral consent and participation. For patients who agreed to taper their opioid dose, the TPS clinician developed an individualized taper plan with the patient that included weekly follow-up and non-pharmacological pain management approaches. TPS facilitated coordination of care with other providers involved with the patient’s care (eg, primary care, surgical team) for as long as they were willing to continue opioid tapering. Once a patient tapered off opioids or reached a tapering plateau, their care was returned to a chronic pain provider and/or a patient care provider. For patients who declined an opioid taper, they continued to receive TPS services for management of acute surgical pain for at least 90 days or until they were returned to baseline opioid dosing.
Degree of opioid tapering after surgery
Patients with baseline COU prior to surgery were stratified based on whether they had complete, partial, or no opioid tapering from their baseline opioid dose at 90 days following their procedure. Opioid use at baseline and all follow-up time points (2, 7, 14, 21, 30, 60, and 90 days after hospital discharge) was converted into oral morphine equivalent daily dose (MEDD) based on established Centers for Disease Control and Prevention conversion factors.15 Opioid use at baseline and throughout the study was assessed and validated by a combination of direct patient interview, review of medical records and state-controlled substance databases. As previously defined, patients were designated as COU if they had a prescription for opioids for 60 continuous days prior to surgery or if they had filled three or more prescriptions for opioids within 180 days prior to surgery.13 14 Patients only prescribed opioids in the immediate preoperative period were not included in the COU cohort. Complete opioid tapering was defined as MEDD=0 at 90 days and cessation was confirmed by patient report and review of the medical record and state controlled substance database. Partial tapering was defined as 90-day MEDD<baseline MEDD, and no tapering was defined as 90-day MEDD≥baseline MEDD.
Outcomes: PROM for pain control
The primary outcomes of the longitudinal analysis were changes in PROM scores designed for pain catastrophizing, pain intensity, and pain interference that were measured longitudinally on each COU patient at baseline before surgery and at 90 days after surgery. The Pain Catastrophizing Scale (PCS) is a validated instrument that contains 13 items related to a patient’s thoughts and feelings about pain.16 We used PROMs from the Patient-Reported Outcomes Measurement Information System (PROMIS) that have been validated for pain intensity (PROMIS 3a), and pain interference (PROMIS 6b). The PROMIS 3a instrument assesses how much a person hurts, whereas the PROMIS 6b scale measures the degree to which pain hinders a patient’s daily life physically, socially, emotionally, and cognitively. PROMIS 3a scores were obtained prior to surgery and at postdischarge days 2, 7, 14, 21, 30, 60, and 90. PROMIS 6b scores were obtained prior to surgery and at postdischarge days 14, 21, 60 and 90. Both PROMIS 3a and 6b measures are calibrated to follow a normal distribution at the population level with scores ranging from 1 to 100 points, a mean T-score of 50, and an SD of 10. For either of these PROMIS measures, a lower score is associated with improved pain intensity or pain interference.
As previously validated, a minimally clinically important difference in PROMIS scores was defined as a change in score of ≥5.0 points over time.17 18 A secondary outcome measure was MEDD daily dose, which was obtained at baseline and all follow-up time points.
Analysis of 90-day change in PROM scores
Patient demographics and clinical measures before and after surgery were summarized descriptively based on the degree of tapering of MEDD at 90 days after surgery (complete, partial, or no opioid tapering). Continuous variables were summarized as mean with SD or median and IQR and compared between groups using analysis of variance or Kruskal-Wallis tests, depending on whether data were normally distributed or skewed. Categorical variables were summarized as frequency and percent and compared using χ2 tests or Fisher’s exact tests if the expected count in any of the groups is fewer than 5. The change from baseline in PROM pain scores (PROMIS 3a and 6b) at 90 days after surgery were compared using Kruskal Wallis tests.
Qualitative analysis
Using the quota sampling technique, we recruited 31 patient participants from the SLC-VAHC who completed a 90-day assessment following hospital discharge from each of the following groups based on degree of tapering: complete taper, partial taper, and no taper. An additional 10 caregiver participants were recruited from the complete taper and partial taper groups to determine if responses were consistent with the themes established from patient interviews. All semistructured interviews were conducted by research analysts from the VA Qualitative Research Core (VA QRC), and occurred between February 2019 and March 2020. Research analysts in the VA QRC were extensively trained in conducting qualitative interviews and independent from the study team. The interview guide was designed to query patient and caregiver perceptions of opioid tapering and its impact on different behavioral aspects of daily life (online supplemental appendix A). We prescreened and iteratively revised our interview scripts with several test patients to ensure uniform understanding of each question. All interviews were audiorecorded and professionally transcribed verbatim for later analysis.
Supplemental material
The transcribed data set was coded and analyzed in the qualitative research software ATLAS.ti following the qualitative coding philosophy developed by Crabtree and Miller.19 The codebook was created through ‘open-coding’, consistent with Crabtree and Miller’s Editing Approach: a process of developing codes for salient concepts as they emerge during the analysis process. To ensure intercoder reliability, two VA QRC team members independently coded and discussed the results for transcripts with a neutral team member to reconcile differences. The codebook was finalized using the constant comparative approach.
Results
Quantitative analysis
We identified 211 patients with preoperative COU who underwent a major surgical procedure at the SLC-VAHC between January 2018 and December 2020 and were enrolled in the TPS program. Complete data were collected on all patients in this cohort during the 90-day follow-up period. This cohort included patients undergoing cardiothoracic (3%), otolaryngology (1%), general surgery (16%), orthopedic surgery (69%), urological surgery (4%), and vascular surgery (7%) procedures (table 1).
Characteristics of chronic opioid use patients, stratified by the degree of opioid tapering achieved at 90 days after surgery
A total of 42 (20%) COU patients in this cohort were able to completely taper off opioids, 48 (23%) were able to partially taper, and 121 (57%) did not taper from baseline opioid requirements within 90 days after their hospital discharge. Preoperative median (IQR) MEDD was significantly lower among patients able to completely taper (19 (10–30)) as compared with patients in the partial (52 (22–90)) and no-taper groups (40 (20–90))(p<0.001). The majority of reduction in MEDD after hospital discharge occurred in the first 30 days among patients with complete and partial opioid tapering (figure 2). As shown in table 1, the demographics, mental health risk factors, and substance abuse risk factors were not significantly different among patients who had complete or partial opioid taper after surgery compared with those who did not have any opioid tapering. However, patients unable to taper off opioids were more likely to have a history of OUD, spent fewer days in the hospital after surgery, and were discharged home on a higher MEDD than patients in the partial and complete opioid taper groups (figure 2; p=0.020).
Change in morphine milligram equivalent daily dose (MEDD) within 90 days after hospital discharge among surgical patients with COU who achieved complete, partial or no opioid tapering. COU, chronic opioid use.
Baseline median (IQR) pain intensity (PROMIS 3a) scores were not significantly different between COU patients in partial (58 (52–60)), complete (54 (50–58)) and no-taper groups (54 (52–60)) (p=0.60). By day 30 after surgery, however, pain intensity PROM scores were significantly lower for patients with complete opioid tapering relative to baseline (p=0.006) when compared with those no opioid tapering (figure 3). This trend continued for COU patients with complete opioid tapering until 90 days after surgery, but no difference was found in PROMIS 3a score changes relative to baseline across all tapering groups over the same time period (table 2).
Change in patient-reported outcome measures associated with pain control, stratified by the degree of opioid tapering achieved at 90 days after surgery among chronic opioid users
Change in patient-reported pain intensity (PROMIS 3a) within 90 days after hospital discharge relative to baseline PROMIS scores among surgical patients with COU who achieved complete, partial or no opioid tapering. COU, chronic opioid use; PROMIS, Patient-Reported Outcomes Measurement Information System.
Similarly, there was no difference in median (IQR) pain interference (PROMIS 6b) scores at baseline among COU patients in partial (66 (61–68)), complete (66 (61–68) and no-taper groups (66 (60–70)) (p=0.89). By 30 days after surgery, patients who achieved complete or partial opioid tapering were found to have a significant improvement in PROMIS 3b scores as compared with patients with no-opioid tapering (p=0.006). This significant difference in PROMIS 3b scores relative to baseline for patients in each opioid tapering group continued through 90 days (figure 4 and table 2). Overall, the 90-day change in pain interference was significantly improved for patients who achieved complete or partial opioid tapering as compared with no opioid taper (figure 3). Finally, there was also significant differences in the amount of decrease in PCS over the 90-day period after surgery across tapering groups, with patients achieving complete or partial opioid tapering demonstrating the greatest improvements (table 2).
Change in patient-reported pain interference (PROMIS 3b) within 90 days after hospital discharge relative to baseline PROMIS scores among surgical patients with COU who achieved complete, partial or no opioid tapering. COU, chronic opioid use; PROMIS, Patient-Reported Outcomes Measurement Information System.
Qualitative analysis
We conducted 41 semistructured interviews, which included 31 patients who had undergone an operative procedure, and 10 life partners/caregivers for Veterans who had undergone surgery. Interviews lasted an average of ~24.5 min, with the shortest 9 min and the longest 59 min. Participants were stratified into three groups based on degree of tapering: complete taper (n=11), partial taper (n=10), and no taper (n=10). For caregiver participants, we interviewed complete taper (n=5) and partial taper (n=5) groups to determine if responses were consistent with the themes established from patient interviews. We achieved thematic saturation from the combination of these groups, indicating that it was unlikely that additional interviews would provide additional information. We identified four themes concerning the impact of opioid tapering on changes in patient’s daily behaviors and QOL (table 3). The primary themes identified included daily activity level, cognition/thinking, mood, and sleep patterns.
Qualitative findings from interviews among chronic opioid user patients about behavioral change themes related to different degrees of opioid tapering achieved at 90 days after surgery
Activity
Patients reflected that their energy levels and the ability to participate in social activities improved with opioid tapering after surgery. A reduction or cessation of daily opioid use corresponded to increased activity and energy levels. This sentiment was echoed by caregivers who stated that patients with partial and complete opioid tapering appeared more alert and typically had more stamina to engage in physical activities throughout the week. In contrast, patients who were not able to taper their opioid requirement after surgery stated that daily activity levels were often limited by how severe their pain was.
Cognition and thinking
Most patients described some degree of improvement in attention, memory, and/or executive functions when partial or complete opioid tapering was achieved after surgery. They reported feeling more ‘clear-headed’ as opioid use decreased, which was supported by similar comments from caregivers. In contrast, patients who did not achieve any reduction in opioid use after surgery did not report any changes in cognition or improvements in their thinking abilities.
Mood
Patients who achieved partial and complete opioid tapering within 90 days after surgery described feeling more positive and having an improvement in their overall mood. They were less likely to report having anxiety, apathy or depression when their opioid use declined. In comparison, patients who continued to be on high doses of chronic opioids often described mood swings and having a negative temperament.
Sleep patterns
The majority of patients who achieved partial or complete opioid tapering within 90 days after surgery perceived that they were able to sleep better. This included an ability to get to sleep more quickly as well as experiencing a greater duration of sleep and having less need for sleep medications. Caregivers also reported that patients were less restless at night as opioid use declined. In comparison, patients who were on their baseline opioid requirements often reported having insomnia or no change to their sleep habits when compared with before surgery.
Discussion
Patients commonly present for major surgery with a history of COU, and widespread strategies have been designed to taper patients off opioids as a means to reduce the harmful long-term health effects of these medications. However, it has been unclear whether strategies designed to reduce opioid use can be applied to surgical patients in the immediate postoperative period without having an adverse effect on their pain control or their QOL. In this study, we show that the ability of chronic opioid users to achieve either partial of complete opioid tapering within the 90-day period after surgery was associated with significant improvements in PROMs for pain interference and pain catastrophizing. Further, our qualitative findings indicate that reducing opioid use after surgery has a positive association with changes in behaviors that can impact a patient’s QOL. Veterans that achieved partial or complete cessation of opioid use reported significant improvements in their mood, energy, memory, and sleep patterns, whereas patients who did not taper opioid use continued to suffer negative health effects of opioid use. These findings support the application of strategies aimed to taper patients off opioids within the 90-day period after surgery in order to achieve positive health benefits without fear of adverse side effects among long-standing users.
Over the past decade, numerous multidisciplinary initiatives have been implemented throughout US healthcare system to combat the epidemic of opioid abuse and reduce the harms associated with long-term opioid use. The opioid safety initiative (OSI), in particular, was implemented in 2013 throughout the VHA as a strategy to decrease opioid prescribing and prevent opioid abuse disorder among patients taking opioids for chronic pain.20 Implementation of the VHA OSI program was found to reduce postoperative opioid use and COU among Veterans undergoing orthopedic surgery.5 But there has also been concern that pain is being undertreated as opioid prescriptions have declined from the efforts of this program and others.21 A recent population study showed that while the VA OSI program helped decrease opioid use among patients undergoing orthopedic procedures, there was a corresponding increase in average pain scores reported among these same types of patients after surgery.22 Similarly, non-consensual opioid tapering among non-surgical COU patients has been associated with worsening mental health and increased risk for withdrawal or overdose.11 These findings have raised concerns that opioid tapering among chronic users after surgery might have unanticipated consequence on other aspects of a patient’s QOL.
In contrast, the results of this study show that individualized pain management strategies such as TPS can achieve significant reductions in MEDD among COU patients during the postoperative period, which was associated with improving patient-reported measures of pain control and improving QOL. These findings are supported by our prior study that demonstrated a significant increase in the proportion of patients who achieved partial or complete opioid tapering after implementation of the TPS intervention.14 TPS is a comprehensive approach to perioperative pain management whereby education, non-opioid options for pain control, pain psychology, and individualized tapering plans are constantly reinforced to patients in the preoperative, in-hospital, and postdischarge period.10 14 Opioid tapering started only with consent and participation of the patient and PROMs are collected specific for pain intensity, interference, and catastrophizing during the taper period. By linking opioid reduction to patient feedback from these PROMs, TPS providers can customize the opioid taper schedule and overall pain management strategy. Further, it is notable that opioid tapering was less successful in our study among patients with shorter length of hospital stays. These findings suggest that patient’s willingness to pursue opioid tapering was impacted by the number of interactions and extent of the relationship able to be established with TPS providers.
But there are other factors that might influence whether a COU patient will be able to taper opioids after surgery. A recent qualitative study of COU patients suggested that motivational factors for opioid tapering were driven by their fear of dependency and the prospect of better health, which was balanced by barriers to tapering that included patient fear of increased pain and withdrawal symptoms.23 While all patient groups were able to taper during their hospital stay, our study also suggests that preoperative MEDD predicts whether patient will be able to taper after discharge. There was a dose-dependent effect whereby patients who were unable to taper had an average MEDD before surgery that was 40, whereas those complete tapering had a significantly lower preoperative MEDD below 20. These findings can be used to help identify patients before surgery that will be good candidates for postsurgical opioid tapering, as well as set realistic expectations.
Our study has several important limitations. First, as with any observational study, there may have been unmeasured factors that impacted the success of opioid tapering and pain control among subjects in our study cohort. While we found no difference in prevalence of established risk factors for OUD between tapering groups, there may have been other sociodemographic factors impacting a patient’s willingness to taper. Second, there was a lot of heterogeneity in the degree of baseline opioid use between tapering groups as well as heterogeneity in how much opioid use was diminished by 90 days after surgery among patients who were defined in the partial tapering group. Third, data were obtained from COU patients undergoing surgery at a single veterans administration medical center (VAMC) who were enrolled in a program designed to maximize non-opioid pain management strategies and to encourage and facilitate opioid tapering. This was primarily male patients and the majority underwent orthopedic joint procedures. It is unclear whether results among these patients can be generalized to COU patients at non-VA institutions or those undergoing non-orthopedic procedures. Fourth, our study was able to show an association between opioid tapering and improvements in patient behavior or mood, but is unable to establish a causal relationship. A prospective randomized controlled study is needed to demonstrate the causal effect of the TPS intervention on improvements in PROMs. Fifth, we used a quota sampling technique to choose subjects within each opioid taper groups for interviews. This selection process may have introduced bias by the research team leading to a sample that was not representative of other patients in each taper group. Finally, interview data by participants in each tapering group was subject to recall bias. To limit this bias, we performed interviews with subjects as close to the time after they have completed a 90-day follow-up after surgery to query about the impact of tapering on QOL.
Conclusions
The results of this study show that the ability for patients with COU to taper their opioid requirements after surgery is associated with significant improvements in pain control and QOL. In fact, many negative health effects associated with chronic opioid are not found in Veterans within 90 days after surgery when their opioid use has been significantly reduced. This includes perceived improvements in mood, energy, memory, and sleep patterns among patients with partial and complete opioid tapering, whereas individuals unable to taper opioid use continued to suffer negative health effects of opioid use. Further work is needed to implement strategies that permit successful opioid tapering after surgery and help improve patient’s QOL.
Data availability statement
Data are available on reasonable request.
Ethics statements
Patient consent for publication
Ethics approval
The University of Utah Institutional Review Board (IRB) and the Salt Lake City VA Health Care System Office of Research and Development approved the protocol for this prospective qualitative study, and written informed consent was obtained from all interviewed subjects prior to study enrollment (IRB Protocol #00117605). A separate protocol was approved by the IRB with waived consent for the retrospective review of electronic patient data based on degree of opioid tapering (IRB Protocol #001060878).
Acknowledgments
We would like to acknowledge the clinical providers on the TPS team: David Merrill RN, Alysia Erickson RN, Jennifer Blue, MSN, Justin Carrell RN, Christian DeGrey APRN, and Cassie Dance PsyD, who have ensured the success and sustainability of this program at the VA SLC. In addition, we acknowledge the work by research analysts from the VA Qualitative Research Core who conducted the qualitative interviews and thematic analysis. Funding for the implementation and evaluation of the TPS was received from the VA Whole Health Initiative, the VA Center of Innovation, the VA Office of Rural Health, and National Institutes of Health Grant UL1TR002538. Funders had no role in the collection, interpretation, and/or reporting of data in this manuscript. None of the authors have any financial interests to declare, which could potentially benefit from the outcomes of this research.
References
Supplementary materials
Supplementary Data
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Footnotes
X @BenjaminSBrooke, @DrKimBaylessNP
Contributors All authors (BSB, KB, ZA, TAH, CZ, JH and MJB) made substantial contributions to the study design, data analysis, and data interpretation, actively participated in drafting and critically revising the manuscript, provided final approval of the submitted version, and agree to be held accountable for the accuracy and integrity of the finished publication. BSB is the guarantor who accepts full responsibility for the finished work and the conduct of the study as well as having access to the data and controlled the decision to publish.
Funding This study was funded by Office of Rural Health (14434).
Competing interests None declared.
Provenance and peer review Not commissioned; externally peer reviewed.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.