CHOIRBM: An R package for exploratory data analysis and interactive visualization of pain patient body map data.

Body maps are commonly used to capture the location of a patient's pain and thus reflect the extent of pain throughout the body. With increasing electronic capture body map information, there is an emerging need for clinic- and research-ready tools capable of visualizing this data on individual and mass scales. Here we propose CHOIRBM, an extensible and modular R package and companion web application built on the grammar of graphics system. CHOIRBM provides functions that simplify the process of analyzing and plotting patient body map data integrated from the CHOIR Body Map (CBM) at both individual patient and large-dataset levels. CHOIRBM is built on the popular R graphics package, ggplot2, which facilitates further development and addition of functionality by the open-source development community as future requirements arise. The CHOIRBM package is distributed under the terms of the MIT license and is available on CRAN. The development version of the package with the latest functions may be installed from GitHub. Example analysis using CHOIRBM demonstrates the functionality of the modular R package and highlights both the clinical and research utility of efficiently producing CBM visualizations.

Mindfulness-Based Stress Reduction, Cognitive Behavioral Therapy, and Acupuncture in Chronic Low Back Pain: Protocol for Two Linked Randomized Controlled Trials.

BACKGROUND: Nonpharmacologic mind-body therapies have demonstrated efficacy in low back pain. However, the mechanisms underlying these therapies remain to be fully elucidated. OBJECTIVE: In response to these knowledge gaps, the Stanford Center for Low Back Pain-a collaborative, National Institutes of Health P01-funded, multidisciplinary research center-was established to investigate the common and distinct biobehavioral mechanisms of three mind-body therapies for chronic low back pain: cognitive behavioral therapy (CBT) that is used to treat pain, mindfulness-based stress reduction (MBSR), and electroacupuncture. Here, we describe the design and implementation of the center structure and the associated randomized controlled trials for characterizing the mechanisms of chronic low back pain treatments. METHODS: The multidisciplinary center is running two randomized controlled trials that share common resources for recruitment, enrollment, study execution, and data acquisition. We expect to recruit over 300 chronic low back pain participants across two projects and across different treatment arms within each project. The first project will examine pain-CBT compared with MBSR and a wait-list control group. The second project will examine real versus sham electroacupuncture. We will use behavioral, psychophysical, physical measure, and neuroimaging techniques to characterize the central pain modulatory and emotion regulatory systems in chronic low back pain at baseline and longitudinally. We will characterize how these interventions impact these systems, characterize the longitudinal treatment effects, and identify predictors of treatment efficacy. RESULTS: Participant recruitment began on March 17, 2015, and will end in March 2023. Recruitment was halted in March 2020 due to COVID-19 and resumed in December 2021. CONCLUSIONS: This center uses a comprehensive approach to study chronic low back pain. Findings are expected to significantly advance our understanding in (1) the baseline and longitudinal mechanisms of chronic low back pain, (2) the common and distinctive mechanisms of three mind-body therapies, and (3) predictors of treatment response, thereby informing future delivery of nonpharmacologic chronic low back pain treatments. TRIAL REGISTRATION: ClinicalTrials.gov NCT02503475; https://clinicaltrials.gov/ct2/show/NCT02503475. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/37823.

Engagement in Prescription Opioid Tapering Research: the EMPOWER Study and a Coproduction Model of Success.

Patients with chronic pain experience stigma within the healthcare system. This stigma is compounded for those taking long-term prescription opioids. Often, public messaging and organizational policies have telegraphed that opioid treatment is a problem to be solved by focusing only on medication reduction efforts. Lack of data has contributed to misperceptions and poor opioid policies. In part, data collection remains poor because patients feel fractured from systems of care and are often not interested in engaging with opioid reduction mandates and research. Similarly, clinicians may fail to engage with opioid stewardship and research due to complexities that exceed their training or capacities. The EMPOWER study applies a coproduction model that engages researchers, patients, clinicians, managers, and other health system users. Key stakeholders shaped the design of the study to best ensure acceptability and engagement of the "end users"-patients who enroll in the study and the clinicians who implement the opioid tapers. Targeting the needs of any stakeholder group in isolation is suboptimal. Accordingly, we detail the EMPOWER patient-centered opioid tapering clinical research framework and specific strategies to address stakeholder concerns. We also discuss how this framework may be applied to enhance engagement in healthcare research broadly.

Classifying chronic pain using multidimensional pain-agnostic symptom assessments and clustering analysis.

Chronic pain conditions present in various forms, yet all feature symptomatic impairments in physical, mental, and social domains. Rather than assessing symptoms as manifestations of illness, we used them to develop a chronic pain classification system. A cohort of real-world treatment-seeking patients completed a multidimensional patient-reported registry as part of a routine initial evaluation in a multidisciplinary academic pain clinic. We applied hierarchical clustering on a training subset of 11,448 patients using nine pain-agnostic symptoms. We then validated a three-cluster solution reflecting a graded scale of severity across all symptoms and eight independent pain-specific measures in additional subsets of 3817 and 1273 patients. Negative affect­related factors were key determinants of cluster assignment. The smallest subset included follow-up assessments that were predicted by baseline cluster assignment. Findings provide a cost-effective classification system that promises to improve clinical care and alleviate suffering by providing putative markers for personalized diagnosis and prognosis.

Comparison of a Single-Session Pain Management Skills Intervention With a Single-Session Health Education Intervention and 8 Sessions of Cognitive Behavioral Therapy in Adults With Chronic Low Back Pain: A Randomized Clinical Trial.

Importance: Chronic low back pain (CLBP), the most prevalent chronic pain condition, imparts substantial disability and discomfort. Cognitive behavioral therapy (CBT) reduces the effect of CLBP, but access is limited. Objective: To determine whether a single class in evidence-based pain management skills (empowered relief) is noninferior to 8-session CBT and superior to health education at 3 months after treatment for improving pain catastrophizing, pain intensity, pain interference, and other secondary outcomes. Design, Setting, and Participants: This 3-arm randomized clinical trial collected data from May 24, 2017, to March 3, 2020. Participants included individuals in the community with self-reported CLBP for 6 months or more and an average pain intensity of at least 4 (range, 0-10, with 10 indicating worst pain imaginable). Data were analyzed using intention-to-treat and per-protocol approaches. Interventions: Participants were randomized to (1) empowered relief, (2) health education (matched to empowered relief for duration and format), or (3) 8-session CBT. Self-reported data were collected at baseline, before treatment, and at posttreatment months 1, 2, and 3. Main Outcomes and Measures: Group differences in Pain Catastrophizing Scale scores and secondary outcomes at month 3 after treatment. Pain intensity and pain interference were priority secondary outcomes. Results: A total of 263 participants were included in the analysis (131 women [49.8%], 130 men [49.4%], and 2 other [0.8%]; mean [SD] age, 47.9 [13.8] years) and were randomized into 3 groups: empowered relief (n = 87), CBT (n = 88), and health education (n = 88). Empowered relief was noninferior to CBT for pain catastrophizing scores at 3 months (difference from CBT, 1.39 [97.5% CI, -∞ to 4.24]). Empowered relief and CBT were superior to health education for pain catastrophizing scores (empowered relief difference from health education, -5.90 [95% CI, -8.78 to -3.01; P < .001]; CBT difference from health education, -7.29 [95% CI, -10.20 to -4.38; P < .001]). Pain catastrophizing score reductions for empowered relief and CBT at 3 months after treatment were clinically meaningful (empowered relief, -9.12 [95% CI, -11.6 to -6.67; P < .001]; CBT, -10.94 [95% CI, -13.6 to -8.32; P < .001]; health education, -4.60 [95% CI, -7.18 to -2.01; P = .001]). Between-group comparisons for pain catastrophizing at months 1 to 3 were adjusted for baseline pain catastrophizing scores and used intention-to-treat analysis. Empowered relief was noninferior to CBT for pain intensity and pain interference (priority secondary outcomes), sleep disturbance, pain bothersomeness, pain behavior, depression, and anxiety. Empowered relief was inferior to CBT for physical function. Conclusions and Relevance: Among adults with CLBP, a single-session pain management class resulted in clinically significant improvements in pain catastrophizing, pain intensity, pain interference, and other secondary outcomes that were noninferior to 8-session CBT at 3 months. Trial Registration: ClinicalTrials.gov Identifier: NCT03167086.

A Brief Screening Tool for Opioid Use Disorder: EMPOWER Study Expert Consensus Protocol.

Growing concerns about the safety of long-term opioid therapy and its uncertain efficacy for non-cancer pain have led to relatively rapid opioid deprescribing in chronic pain patients who have been taking opioid for years. To date, empirically supported processes for safe and effective opioid tapering are lacking. Opioid tapering programs have shown high rates of dropouts and increases in patient distress and suicidal ideation. Therefore, safe strategies for opioid deprescribing that are more likely to succeed are urgently needed. In response to this demand, the EMPOWER study has been launched to examine the effectiveness of behavioral medicine strategies within the context of patient-centered opioid tapering in outpatient settings (https://empower.stanford.edu/). The EMPOWER protocol requires an efficient process for ensuring that collaborative opioid tapering would be offered to the most appropriate patients while identifying patients who should be offered alternate treatment pathways. As a first step, clinicians need a screening tool to identify patients with Opioid Use Disorder (OUD) and to assess for OUD severity. Because such a tool is not available, the study team composed of eight chronic pain and/or addiction experts has extended a validated screening instrument to develop a brief and novel consensus screening tool to identify OUD and assess for OUD severity for treatment stratification. Our screening tool has the potential to assist busy outpatient clinicians to assess OUD among patients receiving long-term opioid therapy for chronic pain.

Development and validation of the Collaborative Health Outcomes Information Registry body map.

INTRODUCTION: Critical for the diagnosis and treatment of chronic pain is the anatomical distribution of pain. Several body maps allow patients to indicate pain areas on paper; however, each has its limitations. OBJECTIVES: To provide a comprehensive body map that can be universally applied across pain conditions, we developed the electronic Collaborative Health Outcomes Information Registry (CHOIR) self-report body map by performing an environmental scan and assessing existing body maps. METHODS: After initial validation using a Delphi technique, we compared (1) pain location questionnaire responses of 530 participants with chronic pain with (2) their pain endorsements on the CHOIR body map (CBM) graphic. A subset of participants (n = 278) repeated the survey 1 week later to assess test-retest reliability. Finally, we interviewed a patient cohort from a tertiary pain management clinic (n = 28) to identify reasons for endorsement discordances. RESULTS: The intraclass correlation coefficient between the total number of body areas endorsed on the survey and those from the body map was 0.86 and improved to 0.93 at follow-up. The intraclass correlation coefficient of the 2 body map graphics separated by 1 week was 0.93. Further examination demonstrated high consistency between the questionnaire and CBM graphic (<10% discordance) in most body areas except for the back and shoulders (≈15-19% discordance). Participants attributed inconsistencies to misinterpretation of body regions and laterality, the latter of which was addressed by modifying the instructions. CONCLUSIONS: Our data suggest that the CBM is a valid and reliable instrument for assessing the distribution of pain.

Self-reported traumatic etiology of pain and psychological function in tertiary care pain clinic patients: a collaborative health outcomes information registry (CHOIR) study.

Background and aims A sizable body of research has elucidated the significant role of psychological reactions to trauma on pain coping and outcomes. In order to best inform intervention development and clinical care for patients with both trauma and pain at the tertiary care level, greater clarity is needed regarding the magnitude of these effects and the specific pathways through which they may or may not function at the time of first presentation to such a treatment setting. To achieve this, the current study examined the cross-sectional relationships between traumatic etiology of pain, psychological distress (anger, depressive symptoms, and PTSD symptoms), and pain outcomes (pain catastrophizing, physical function, disability status). Methods Using a structural path modeling approach, analyses were conducted using a large sample of individuals with chronic pain (n = 637) seeking new medical evaluation at a tertiary pain management center, using the Collaborative Health Outcomes Information Registry (CHOIR). We hypothesized that the relationships between traumatic etiology of pain and poorer pain outcomes would be mediated by higher levels of psychological distress. Results Our analyses revealed modest relationships between self-reported traumatic etiology of pain and pain catastrophizing, physical function, and disability status. In comparison, there were stronger relationships between indices of psychological distress and pain catastrophizing, but a weaker pattern of associations between psychological distress and physical function and disability measures. Conclusions To the relatively small extent that self-reported traumatic etiology of pain correlates with pain-related outcomes, these relationships appear to be due primarily to the presence of psychiatric symptoms and manifest most notably in the context of psychological responses to pain (i.e. catastrophizing about pain). Implications Findings from this study highlight the need for early intervention for patients with traumatic onset of pain and for clinicians at tertiary pain centers to include more detailed assessments of psychological distress and trauma as a component of comprehensive chronic pain treatment.

Comparative Effectiveness of Cognitive Behavioral Therapy for Chronic Pain and Chronic Pain Self-Management within the Context of Voluntary Patient-Centered Prescription Opioid Tapering: The EMPOWER Study Protocol.

OBJECTIVE: Evidence to date, while sparse, suggests that patients taking long-term opioids require special considerations and protections to prevent potential iatrogenic harms from opioid de-prescribing, such as increased pain or suffering. Following this study protocol, the EMPOWER study seeks to address multiple unmet needs of patients with chronic pain who desire to reduce long-term opioid therapy, and provide the clinical evidence on effective methodology. METHODS: EMPOWER applies patient-centered methods for voluntary prescription opioid reduction conducted within a comprehensive, multi-state, 3-arm randomized controlled comparative effectiveness study of three study arms (1) group cognitive behavioral therapy for chronic pain; (2) group chronic pain self-management; and (3) usual care (taper only). Specialized electronic data capture systems collect patient reported symptoms and satisfaction data weekly and monthly during the taper, with real-time clinical alerts and electronic feedback loops informing, documenting, and steering needed care actions. CONCLUSION: The EMPOWER study seeks to provide granular evidence on patient response to voluntary opioid tapering, and will provide evidence to inform clinical systems changes, clinical care, patient satisfaction, and patient outcomes for opioid reduction.

Smoking Is Associated with Pain in All Body Regions, with Greatest Influence on Spinal Pain.

OBJECTIVE: Examine the interrelationship between smoking and pain in the US population. DESIGN: A cross-sectional population-based study. SETTING: Nationwide survey. METHODS: Comprehensive pain reports categorically defined as head, spine, trunk, and limb pain; smoking history; demographics; medical history from a total of 2,307 subjects from the 2003-2004 National Health and Nutrition Examination Survey obtained from the Centers for Disease Control were analyzed. Unpaired t tests were used to analyze independent continuous variables, and chi-square tests were used to analyze categorical variables between smoker and nonsmoker groups. Weighted multivariate logistic regression analyses determined the association of current smoking with the presence of pain in various body regions. RESULTS: Smoking is most strongly associated with spine pain (odds ratio [OR] = 2.89, 95% confidence interval [CI] = 2.21-3.77), followed by headache (OR = 2.47, 95% CI = 1.73-3.53), trunk pain (OR = 2.17, 95% CI = 1.45-2.74), and limb pain (OR = 1.99, 95% CI = 1.45-2.73). CONCLUSIONS: Current smoking is associated with pain in every region of the body. This association is strongest for spine and head pain. Given that pain is a strong motivator and that current smoking was associated with pain in all body regions, we recommend that these results be used to further raise public awareness about the potential harms of smoking.

Central mechanisms of real and sham electroacupuncture in the treatment of chronic low back pain: study protocol for a randomized, placebo-controlled clinical trial.

BACKGROUND: Chronic low back pain (CLBP) is the most common chronic pain condition and is often resistant to conventional treatments. Acupuncture is a popular alternative for treating CLBP but its mechanisms of action remain poorly understood. Evidence suggests that pain regulatory mechanisms (particularly the ascending and secondarily the descending pain modulatory pathways) and psychological mechanisms (e.g., expectations, pain catastrophizing and self-efficacy) may be involved in the pathogenesis of CLBP and its response to treatments. We will examine these mechanisms in the treatment of CLBP by electroacupuncture (EA). METHODS: We present the aims and methods of a placebo-controlled, participant-blinded and assessor-blinded mechanistic study. Adult patients with CLBP will be randomized to receiving 16 sessions of real (active) or sham (placebo) EA over the course of 8 weeks. The primary pain regulatory measure for which the study was powered is temporal summation (TS), which approximates ascending pain facilitation. Conditioned pain modulation (CPM), representing a descending pain modulatory pathway, will be our secondary pain regulatory measure. The primary psychological measure is expectations of benefit, and the secondary psychological measures are pain catastrophizing and self-efficacy in managing pain. Main clinical outcomes are back pain bothersomeness on a 0-100 visual analog scale (primary), Roland Morris Disability Questionnaire (secondary), and relevant items from the National Institutes of Health (NIH) Patient-Reported Outcome Measures Information System (secondary). We hypothesize that compared to sham, real EA will lead to greater reduction in TS after 8 treatment sessions (4 weeks); and that reduction in TS (and secondarily, increase in CPM) after 8 treatment sessions will mediate reduction in back pain bothersomeness from baseline to week 10 (clinical response) to EA. We also hypothesize that the three psychological factors are moderators of clinical response. With 100 treatment completers, the study is designed to have 80% power to detect a medium-sized between-group effect (d = 0.5) on temporal summation. DISCUSSION: To the best of our knowledge, this is the first appropriately powered, placebo-controlled clinical trial evaluating mechanisms of EA in the treatment of CLBP. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02503475 . Registered on 15 July 15 2015. Retrospectively registered.

Comparative Efficacy and Mechanisms of a Single-Session Pain Psychology Class in Chronic Low Back Pain: Study Protocol for a Randomized Controlled Trial.

BACKGROUND: The Institute of Medicine (IOM) reported that chronic pain affects about 100 million U.S. adults, with chronic low back pain (CLBP) cited as the most prevalent type. Pain catastrophizing is a psychological construct shown to predict the development and trajectory of chronic pain and patient response to pain treatments. While effective treatment for pain catastrophizing typically includes eight-session groups of cognitive behavioral therapy (CBT), a single-session targeted treatment class yielded promising results which, if replicated and extended, could prove to efficiently and cost-effectively reduce pain catastrophizing. In this trial, we seek to determine the comparative efficacy of this novel single-session pain catastrophizing class to an eight-session course of pain CBT and a single-session back pain health education class. We will also explore the psychosocial mechanisms and outcomes of pain catastrophizing treatment. METHODS: In this trial we will randomize 231 individuals with CLBP to one of three treatment arms: (1) pain-CBT (eight weekly 2-h group sessions with home exercises and readings); (2) a single 2-h pain catastrophizing class; or (3) a single 2-h back pain health education class (active control). For the primary outcome of pain catastrophizing, the trial is designed as a non-inferiority test between pain-CBT and the single-session pain catastrophizing class, and as a superiority test between the single-session pain catastrophizing class and the health education class. Team researchers masked to treatment assignment will assess outcomes up to six months post treatment. DISCUSSION: If the single-session targeted pain catastrophizing class is found to be an effective treatment for patients with CLBP, this low cost and low burden treatment could dismantle many of the current barriers and burdens of effective pain care. Further, elucidation of the mechanisms of pain catastrophizing treatments will facilitate future research on the topic as well as further development and refinement of treatments. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03167086 . Registered on 22 May 2017.

Guidelines for Composing and Assessing a Paper on the Treatment of Pain: A Practical Application of Evidence-Based Medicine Principles to the Mint Randomized Clinical Trials.

Objective: To perform a thorough assessment of the recently published Mint Trials in order to illustrate how to read and analyze a study critically, according to principles of evidence-based medicine. Design: Narrative review. Method: We have applied the recently published guidelines for composing and assessing studies on the treatment of pain to a recently published article describing a large study that claimed its "findings do not support the use of radiofrequency denervation to treat chronic low back pain." These guidelines describe the critical components of a high-quality manuscript that allows communication of all relevant information from authors to readers. Results: Application of evidence-based medicine principles to the publication describing the Mint Trials reveals significant issues with the methodology and conclusions drawn by the authors. A thorough assessment demonstrates issues with inclusion/exclusion criteria, diagnostic block protocols, radiofrequency neurotomy technique, co-interventions, outcome measurement, power analysis, study sample characteristics, data analysis, and loss to follow-up. A failure to definitively establish a diagnosis, combined with use of an inadequate technique for radiofrequency neurotomy and numerous other methodological flaws, leaves the reader unable to draw meaningful conclusions from the study data. Conclusions: Critical analysis, rooted in principles of evidence-based medicine, must be employed by writers and readers alike in order to encourage transparency and ensure that appropriate conclusions are drawn from study data.

The Impact of Perceived Injustice on Pain-related Outcomes: A Combined Model Examining the Mediating Roles of Pain Acceptance and Anger in a Chronic Pain Sample.

OBJECTIVE: Perceived injustice (PI) has been identified as an important risk factor for pain-related outcomes. To date, research has shown that pain acceptance and anger are mediators of the association between PI and pain-related outcomes. However, a combined conceptual model that addresses the interrelationships between these variables is currently lacking. Therefore, the current study aimed to examine the potential mediating roles of pain acceptance and anger on the association between PI and adverse pain-related outcomes (physical function, pain intensity, opioid use status). MATERIALS AND METHOD: This cross-sectional study used a sample of 354 patients with chronic pain being treated at a tertiary pain treatment center. Participants completed measures of PI, pain acceptance, anger, physical function, pain intensity, and opioid use status. Mediation analyses were used to examine the impact of pain acceptance and anger on the association between PI and pain-related outcomes. RESULTS: Examination of the specific indirect effects revealed that pain acceptance fully mediated the relationship between PI and physical function, as well as the relationship between PI and opioid use status. Pain acceptance emerged as a partial mediator of the relationship between PI and pain intensity. DISCUSSION: This is the first study to provide a combined conceptual model investigating the mediating roles of pain acceptance and anger on the relationship between PI and pain outcomes. On the basis of our findings, low levels of pain acceptance associated with PI may help explain the association between PI and adverse pain outcomes. Clinical and theoretical implications are discussed.

Pain Catastrophizing Moderates Relationships between Pain Intensity and Opioid Prescription: Nonlinear Sex Differences Revealed Using a Learning Health System.

BACKGROUND: Pain catastrophizing is a maladaptive response to pain that amplifies chronic pain intensity and distress. Few studies have examined how pain catastrophizing relates to opioid prescription in outpatients with chronic pain. METHODS: The authors conducted a retrospective observational study of the relationships between opioid prescription, pain intensity, and pain catastrophizing in 1,794 adults (1,129 women; 63%) presenting for new evaluation at a large tertiary care pain treatment center. Data were sourced primarily from an open-source, learning health system and pain registry and secondarily from manual review of electronic medical records. A binary opioid prescription variable (yes/no) constituted the dependent variable; independent variables were age, sex, pain intensity, pain catastrophizing, depression, and anxiety. RESULTS: Most patients were prescribed at least one opioid medication (57%; n = 1,020). A significant interaction and main effects of pain intensity and pain catastrophizing on opioid prescription were noted (P < 0.04). Additive modeling revealed sex differences in the relationship between pain catastrophizing, pain intensity, and opioid prescription, such that opioid prescription became more common at lower levels of pain catastrophizing for women than for men. CONCLUSIONS: Results supported the conclusion that pain catastrophizing and sex moderate the relationship between pain intensity and opioid prescription. Although men and women patients had similar Pain Catastrophizing Scale scores, historically "subthreshold" levels of pain catastrophizing were significantly associated with opioid prescription only for women patients. These findings suggest that pain intensity and catastrophizing contribute to different patterns of opioid prescription for men and women patients, highlighting a potential need for examination and intervention in future studies.

Stagnant Physical Therapy Referral Rates Alongside Rising Opioid Prescription Rates in Patients With Low Back Pain in the United States 1997-2010.

STUDY DESIGN: A cross-sectional observational study utilizing the National Ambulatory and National Hospital Ambulatory Medical Care Surveys between 1997 and 2010. OBJECTIVE: The aim of this study was to characterize national physical therapy (PT) referral trends during primary care provider (PCP) visits in the United States. SUMMARY OF BACKGROUND DATA: Despite guidelines recommending PT for the initial management of low back pain (LBP), national PT referral rates remain low. METHODS: Race, ethnicity, age, payer type, and PT referral rates were collected for patients aged 16 to 90 years who were visiting their PCPs. Associations among demographic variables and PT referral were determined using logistic regression. RESULTS: Between 1997 and 2010, we estimated 170 million visits for LBP leading to 17.1 million PT referrals. Average proportion of PCP visits associated with PT referrals remained stable at about 10.1% [odds ratio (OR) 1.00, 95% confidence interval (95% CI) 0.96-1.04)], despite our prior finding of increasing number of visits associated with opioid prescriptions in the same timeframe.Lower PT referral rates were observed among visits by patients who were insured by Medicaid (OR 0.48, 95% CI 0.33-0.69) and Medicare (OR 0.50, 95% CI 0.35-0.72). Furthermore, visits not associated with PT referrals were more likely to be associated with opioid prescriptions (OR 1.69, 95% CI 1.22-2.35). CONCLUSION: Although therapies delivered by PTs are promoted as a first-line treatment for LBP, PT referral rates remain low. There also exist disparately lower referral rates in populations with more restrictive health plans and simultaneous opioid prescription. Our findings provide a broad overview to PT prescription trend and isolate concerning associations requiring further explorations. LEVEL OF EVIDENCE: 3.