Roger Chou

Oregon Health and Science University, Portland, Oregon, United States

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Publications (143)1341.15 Total impact

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    ABSTRACT: Use of epidural corticosteroid injections is increasing. To review evidence on the benefits and harms of epidural corticosteroid injections in adults with radicular low back pain or spinal stenosis of any duration. Ovid MEDLINE (through May 2015), Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, prior systematic reviews, and reference lists. Randomized trials of epidural corticosteroid injections versus placebo interventions, or that compared epidural injection techniques, corticosteroids, or doses. Dual extraction and quality assessment of individual studies, which were used to determine the overall strength of evidence (SOE). 30 placebo-controlled trials evaluated epidural corticosteroid injections for radiculopathy, and 8 trials were done for spinal stenosis. For radiculopathy, epidural corticosteroids were associated with greater immediate-term reduction in pain (weighted mean difference on a scale of 0 to 100, -7.55 [95% CI, -11.4 to -3.74]; SOE, moderate), function (standardized mean difference after exclusion of an outlier trial, -0.33 [CI, -0.56 to -0.09]; SOE, low), and short-term surgery risk (relative risk, 0.62 [CI, 0.41 to 0.92]; SOE, low). Effects were below predefined minimum clinically important difference thresholds, and there were no longer-term benefits. Limited evidence showed no clear effects of technical factors, patient characteristics, or comparator interventions on estimates. There were no clear effects of epidural corticosteroid injections for spinal stenosis (SOE, low to moderate). Serious harms were rare, but harms reporting was suboptimal (SOE, low). The review was restricted to English-language studies. Some meta-analyses were based on small numbers of trials (particularly for spinal stenosis), and most trials had methodological shortcomings. Epidural corticosteroid injections for radiculopathy were associated with immediate reductions in pain and function. However, benefits were small and not sustained, and there was no effect on long-term surgery risk. Limited evidence suggested no effectiveness for spinal stenosis.
    Annals of internal medicine 08/2015; 163(5). DOI:10.7326/M15-0934 · 17.81 Impact Factor
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    ABSTRACT: As time and cost constraints in the conduct of systematic reviews increase, the need to consider the use of existing systematic reviews also increases. We developed guidance on the integration of systematic reviews into new reviews. A workgroup of methodologists from Evidence-based Practice Centers (EPCs) developed consensus-based recommendations. Discussions were informed by a literature scan and by interviews with organizations that conduct systematic reviews. Twelve recommendations were developed addressing selecting reviews, assessing risk of bias, qualitative and quantitative synthesis, and summarizing and assessing body of evidence. We provide preliminary guidance for an efficient and unbiased approach to integrating existing systematic reviews with primary studies in a new review. Copyright © 2015 Elsevier Inc. All rights reserved.
    Journal of clinical epidemiology 08/2015; DOI:10.1016/j.jclinepi.2015.05.035 · 3.42 Impact Factor
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    ABSTRACT: Method guideline for systematic reviews of trials of interventions for neck and back pain, and related spinal disordersObjective. To help authors design, conduct and report systematic reviews of trials in this field. In 1997, the Cochrane Back Review Group editorial board published the Method Guideline for Systematic Reviews, which was updated in 2003 and in 2009. Since then, new methodologic evidence has emerged and standards have changed, therefore it was clear that revisions were needed to the 2009 guideline. In May 2015 the group changed its name to Cochrane Back and Neck (CBN). The editorial board met in September 2014 to review the relevant new methodological evidence and determine how it should be incorporated. Members of the advisory board were consulted. Based on the feedback received an updated method guideline was prepared and approved by the editorial board. We have updated recommendations in 7 categories: objectives, literature search, selection criteria, risk of bias assessment, data extraction, data analysis, and reporting of results and conclusions. Each category is classified into minimum criteria (mandatory) and further guidance (optional). This update also includes some new guidance for preparation of summary of finding tables and for conducting non-intervention reviews. Citations of previous versions of the method guideline in published scientific articles (1193 in total) suggest that others may find this guideline useful to plan, conduct, or evaluate systematic reviews in the field of back and neck pain, and spinal disorders.
    Spine 07/2015; DOI:10.1097/BRS.0000000000001061 · 2.30 Impact Factor
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    ABSTRACT: Study Design: This is a systematic review. Objective: This study aims to compare effects of sequestrectomy versus conventional microdiscectomy for lumbar disc herniation. Summary of Background data: Open surgery for LDH can be performed by sequestrectomy or conventional discectomy. Generally, it has been assumed that the former is associated with higher risk of recurrence and less radicular pain and low back pain after surgery. Methods: We searched MEDLINE and EMBASE from 1980 to November 2014. We selected randomized controlled trials (RCTs) and prospective studies that compared conventional discectomy versus sequestrectomy for adult patients with LDH and evaluated the following primary outcomes: radicular pain or LBP as measured by a visual analogue scale, neurological deficit of lower extremity. We also evaluated the following secondary outcomes: complications of surgery, reherniation rate, duration of hospital stay, postoperative analgesic use, and health-related quality of life measures. Two authors independently reviewed citations and articles for inclusion. We assessed the risk of bias as well as the level of evidence for each study, and we used standard methodological procedures recommended by the Cochrane Collaboration. Results: We identified five studies (746 participants) that met our inclusion criteria comparing sequestrectomy versus microdiscectomy. Comparison revealed that with low-quality evidence, there is no significant difference for radicular pain, LBP, functional outcome, complications, and hospital stay for 2 years. In addition, with moderate-quality evidence, there is no significant difference for recurrence rate. Meanwhile, there is very low-quality evidence that analgesic consumption is lower in sequestrectomy than micro/discectomy. Conclusion: Both interventions had similar effect on pain after surgery, recurrence rate, functional outcome, and complications; however, sequestrectomy may be superior in terms of postoperative analgesic consumption.
    Global Spine Journal, Sheraton Buenos Aires Hotel & Convention Center, Buenos Aires, Argentina, 20–23 May 2015; 05/2015
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    ABSTRACT: Several imaging modalities are available for diagnosis of hepatocellular carcinoma (HCC). To evaluate the test performance of imaging modalities for HCC. MEDLINE (1998 to December 2014), the Cochrane Library Database, Scopus, and reference lists. Studies on test performance of ultrasonography, computed tomography (CT), or magnetic resonance imaging (MRI). One investigator abstracted data, and a second investigator confirmed them; 2 investigators independently assessed study quality and strength of evidence. Few studies have evaluated imaging for HCC in surveillance settings. In nonsurveillance settings, sensitivity for detection of HCC lesions was lower for ultrasonography without contrast than for CT or MRI (pooled difference based on direct comparisons, 0.11 to 0.22), and MRI was associated with higher sensitivity than CT (pooled difference, 0.09 [95% CI, 0.07 to 12]). For evaluation of focal liver lesions, there were no clear differences in sensitivity among ultrasonography with contrast, CT, and MRI. Specificity was generally 0.85 or higher across imaging modalities, but this item was not reported in many studies. Factors associated with lower sensitivity included use of an explanted liver reference standard, and smaller or more well-differentiated HCC lesions. For MRI, sensitivity was slightly higher for hepatic-specific than nonspecific contrast agents. Only English-language articles were included, there was statistical heterogeneity in pooled analyses, and costs were not assessed. Most studies were conducted in Asia and had methodological limitations. CT and MRI are associated with higher sensitivity than ultrasonography without contrast for detection of HCC; sensitivity was higher for MRI than CT. For evaluation of focal liver lesions, the sensitivities of ultrasonography with contrast, CT, and MRI for HCC are similar. Agency for Healthcare Research and Quality. (PROSPERO: CRD42014007016).
    Annals of internal medicine 05/2015; 162(10):697-711. DOI:10.7326/M14-2509 · 17.81 Impact Factor
  • Erin S LeBlanc · Roger Chou · Miranda Pappas
    Annals of internal medicine 05/2015; 162(10):738. DOI:10.7326/L15-5094-4 · 17.81 Impact Factor
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    ABSTRACT: Screening for type 2 diabetes mellitus could lead to earlier identification and treatment of asymptomatic diabetes, impaired fasting glucose (IFG), or impaired glucose tolerance (IGT), potentially resulting in improved outcomes. To update the 2008 U.S. Preventive Services Task Force review on diabetes screening in adults. Cochrane databases and MEDLINE (2007 through October 2014) and relevant studies from previous Task Force reviews. Randomized, controlled trials; controlled, observational studies; and systematic reviews. Data were abstracted by 1 investigator and checked by a second; 2 investigators independently assessed study quality. In 2 trials, screening for diabetes was associated with no 10-year mortality benefit versus no screening (hazard ratio, 1.06 [95% CI, 0.90 to 1.25]). Sixteen trials consistently found that treatment of IFG or IGT was associated with delayed progression to diabetes. Most trials of treatment of IFG or IGT found no effects on all-cause or cardiovascular mortality, although lifestyle modification was associated with decreased risk for both outcomes after 23 years in 1 trial. For screen-detected diabetes, 1 trial found no effect of an intensive multifactorial intervention on risk for all-cause or cardiovascular mortality versus standard control. In diabetes that was not specifically screen-detected, 9 systematic reviews found that intensive glucose control did not reduce risk for all-cause or cardiovascular mortality and results for intensive blood pressure control were inconsistent. The review was restricted to English-language articles, and few studies were conducted in screen-detected populations. Screening for diabetes did not improve mortality rates after 10 years of follow-up. More evidence is needed to determine the effectiveness of treatments for screen-detected diabetes. Treatment of IFG or IGT was associated with delayed progression to diabetes. Agency for Healthcare Research and Quality.
    Annals of internal medicine 04/2015; 162(11). DOI:10.7326/M14-2221 · 17.81 Impact Factor
  • Roger Chou
    JAMA Internal Medicine 03/2015; 175(5). DOI:10.1001/jamainternmed.2015.0252 · 13.12 Impact Factor
  • Erin S LeBlanc · Roger Chou
    JAMA Internal Medicine 03/2015; 175(5). DOI:10.1001/jamainternmed.2015.0248 · 13.12 Impact Factor
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    ABSTRACT: Increases in prescriptions of opioid medications for chronic pain have been accompanied by increases in opioid overdoses, abuse, and other harms and uncertainty about long-term effectiveness. To evaluate evidence on the effectiveness and harms of long-term (>3 months) opioid therapy for chronic pain in adults. MEDLINE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, PsycINFO, and CINAHL (January 2008 through August 2014); relevant studies from a prior review; reference lists; and Randomized trials and observational studies that involved adults with chronic pain who were prescribed long-term opioid therapy and that evaluated opioid therapy versus placebo, no opioid, or nonopioid therapy; different opioid dosing strategies; or risk mitigation strategies. Dual extraction and quality assessment. No study of opioid therapy versus no opioid therapy evaluated long-term (>1 year) outcomes related to pain, function, quality of life, opioid abuse, or addiction. Good- and fair-quality observational studies suggest that opioid therapy for chronic pain is associated with increased risk for overdose, opioid abuse, fractures, myocardial infarction, and markers of sexual dysfunction, although there are few studies for each of these outcomes; for some harms, higher doses are associated with increased risk. Evidence on the effectiveness and harms of different opioid dosing and risk mitigation strategies is limited. Non-English-language articles were excluded, meta-analysis could not be done, and publication bias could not be assessed. No placebo-controlled trials met inclusion criteria, evidence was lacking for many comparisons and outcomes, and observational studies were limited in their ability to address potential confounding. Evidence is insufficient to determine the effectiveness of long-term opioid therapy for improving chronic pain and function. Evidence supports a dose-dependent risk for serious harms. Agency for Healthcare Research and Quality.
    Annals of internal medicine 01/2015; 162(4). DOI:10.7326/M14-2559 · 17.81 Impact Factor
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    ABSTRACT: We performed a systematic review to address the comparative effectiveness of different imaging modalities in evaluating treatment response among metastatic breast cancer patients. We searched seven multidisciplinary electronic databases for relevant publications (January 2003-December 2013) and performed dual abstraction of details and results for all clinical studies that involved stage IV breast cancer patients and evaluated imaging for detecting treatment response. Among 159 citations reviewed, 17 single-institution, non-randomized, observational studies met our inclusion criteria. Several studies demonstrate that changes in PET/CT standard uptake values are associated with changes in tumor volume as determined by bone scan, MRI, and/or CT. However, no studies evaluated comparative test performance between modalities or determined relationships between imaging findings and subsequent clinical decisions. Evidence for imaging's effectiveness in determining treatment response among metastatic breast cancer patients is limited. More rigorous research is needed to address imaging's value in this patient population. Copyright © 2014. Published by Elsevier Ltd.
    Breast (Edinburgh, Scotland) 12/2014; 24(1). DOI:10.1016/j.breast.2014.11.009 · 2.38 Impact Factor
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    ABSTRACT: Vitamin D deficiency has been associated with adverse health outcomes. To systematically review benefits and harms of vitamin D screening in asymptomatic adults. Ovid MEDLINE (through the third week of August 2014), Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews. Randomized trials of screening for and treatment of vitamin D deficiency and case-control studies nested within the Women's Health Initiative. One investigator abstracted data, a second reviewed data for accuracy, and 2 investigators independently assessed study quality using predefined criteria. No study examined the effects of vitamin D screening versus no screening on clinical outcomes. Vitamin D treatment was associated with decreased mortality versus placebo or no treatment (11 studies; risk ratio [RR], 0.83 [95% CI, 0.70 to 0.99]), although benefits were no longer seen after trials of institutionalized persons were excluded (8 studies; RR, 0.93 [CI, 0.73 to 1.18]). Vitamin D treatment was associated with possible decreased risk for having at least 1 fall (5 studies; RR, 0.84 [CI, 0.69 to 1.02]) and falls per person (5 studies; incidence rate ratio, 0.66 [CI, 0.50 to 0.88]) but not fractures (5 studies; RR, 0.98 [CI, 0.82 to 1.16]). Vitamin D treatment was not associated with a statistically significant increased risk for serious adverse events (RR, 1.17 [CI, 0.74 to 1.84]). Variability across studies in 25-hydroxyvitamin D assays and baseline levels, treatment doses, use of calcium, and duration of follow-up. Treatment of vitamin D deficiency in asymptomatic persons might reduce mortality risk in institutionalized elderly persons and risk for falls but not fractures. Agency for Healthcare Research and Quality.
    Annals of internal medicine 11/2014; 162(2). DOI:10.7326/M14-1659 · 17.81 Impact Factor
  • Richard A Deyo · Jeffrey G Jarvik · Roger Chou
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    ABSTRACT: In 2004, the U.S. Preventive Services Task Force found insufficient evidence to recommend thyroid screening.
    Annals of internal medicine 10/2014; 162(1). DOI:10.7326/M14-1456 · 17.81 Impact Factor
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    ABSTRACT: Objective The purpose of this article is 1) to present the historical context and rationale for competency-based pain management education; and 2) to suggest learning tools that faculty might apply into their teachings and their institutions' pre-licensure curricula for promoting conceptual learning based on competency-based pain management education.DesignBased on the well-documented need to improve the competency of health care professionals in pain assessment and management, an interprofessional group of health care providers collaborated and then convened in August 2012 to develop core competencies for pain management for the pre-licensure programs of study across health care disciplines. This interprofessional group of pain educators achieved consensus on a common set of pain-related competencies intended to be implemented across a variety of pre-licensure professional programs.SettingA group of the interprofessional faculty, who participated in the development of the core competencies for pain management, provides a follow-up of how to implement learning tools within teaching and curricula, based on competency education in pre-licensure health care.ResultsBroad questions about how to incorporate competencies into pre-licensure curricula, for all health provider pre-licensure programs, including how to assess competency across individuals and how to teach in ways that emphasize the demonstration of conceptual learning, remain unanswered. This article reviews how the use of competencies creates historical context for a shift from teaching to learning and concludes with suggestions and exemplars in applying core competencies for pain management in pre-licensure programs.
    Pain Medicine 10/2014; 16(2). DOI:10.1111/pme.12563 · 2.30 Impact Factor
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    ABSTRACT: Background Seventeen of 172 included studies in a recent systematic review of blood tests for hepatic fibrosis or cirrhosis reported diagnostic accuracy results discordant from 2 × 2 tables, and 60 studies reported inadequate data to construct 2 × 2 tables. This study explores the yield of contacting authors of diagnostic accuracy studies and impact on the systematic review findings. Methods Sixty-six corresponding authors were sent letters requesting additional information or clarification of data from 77 studies. Data received from the authors were synthesized with data included in the previous review, and diagnostic accuracy sensitivities, specificities, and positive and likelihood ratios were recalculated. Results Of the 66 authors, 68% were successfully contacted and 42% provided additional data for 29 out of 77 studies (38%). All authors who provided data at all did so by the third emailed request (ten authors provided data after one request). Authors of more recent studies were more likely to be located and provide data compared to authors of older studies. The effects of requests for additional data on the conclusions regarding the utility of blood tests to identify patients with clinically significant fibrosis or cirrhosis were generally small for ten out of 12 tests. Additional data resulted in reclassification (using median likelihood ratio estimates) from less useful to moderately useful or vice versa for the remaining two blood tests and enabled the calculation of an estimate for a third blood test for which previously the data had been insufficient to do so. We did not identify a clear pattern for the directional impact of additional data on estimates of diagnostic accuracy. Conclusions We successfully contacted and received results from 42% of authors who provided data for 38% of included studies. Contacting authors of studies evaluating the diagnostic accuracy of serum biomarkers for hepatic fibrosis and cirrhosis in hepatitis C patients impacted conclusions regarding diagnostic utility for two blood tests and enabled the calculation of an estimate for a third blood test. Despite relatively extensive efforts, we were unable to obtain data to resolve discrepancies or complete 2 × 2 tables for 62% of studies.
    Systematic Reviews 09/2014; 3(1):107. DOI:10.1186/2046-4053-3-107
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    ABSTRACT: BACKGROUND: Microdiscectomy or open discectomy (MD/OD) are the standard procedures for symptomatic lumbar disc herniation and they involve removal of the portion of the intervertebral disc compressing the nerve root or spinal cord (or both) with or without the aid of a headlight loupe or microscope magnification. Potential advantages of newer minimally invasive discectomy (MID) procedures over standard MD/OD include less blood loss, less postoperative pain, shorter hospitalisation and earlier return to work. OBJECTIVES: To compare the benefits and harms of MID versus MD/OD for management of lumbar intervertebral discopathy. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (November 2013), MEDLINE (1946 to November 2013) and EMBASE (1974 to November 2013) and applied no language restrictions. We also contacted experts in the field for additional studies and reviewed reference lists of relevant studies. SELECTION CRITERIA: We selected randomised controlled trials (RCTs) and quasi-randomised controlled trials (QRCTs) that compared MD/OD with a MID (percutaneous endoscopic interlaminar or transforaminal lumbar discectomy, transmuscular tubular microdiscectomy and automated percutaneous lumbar discectomy) for treatment of adults with lumbar radiculopathy secondary to discopathy. We evaluated the following primary outcomes: pain related to sciatica or low back pain (LBP) as measured by a visual analogue scale, sciatic specific outcomes such as neurological deficit of lower extremity or bowel/urinary incontinence and functional outcomes (including daily activity or return to work). We also evaluated the following secondary outcomes: complications of surgery, duration of hospital stay, postoperative opioid use, quality of life and overall participant satisfaction. Two authors checked data abstractions and articles for inclusion. We resolved discrepancies by consensus. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by The Cochrane Collaboration. We used pre-developed forms to extract data and two authors independently assessed risk of bias. For statistical analysis, we used risk ratio (RR) for dichotomous outcomes and mean difference (MD) for continuous outcomes with 95% confidence intervals (CI) for each outcome. MAIN RESULTS: We identified 11 studies (1172 participants). We assessed seven out of 11 studies as having high overall risk of bias. There was low-quality evidence that MID was associated with worse leg pain than MD/OD at follow-up ranging from six months to two years (e.g. at one year: MD 0.13, 95% CI 0.09 to 0.16), but differences were small (less than 0.5 points on a 0 to 10 scale) and did not meet standard thresholds for clinically meaningful differences. There was low-quality evidence that MID was associated with worse LBP than MD/OD at six-month follow-up (MD 0.35, 95% CI 0.19 to 0.51) and at two years (MD 0.54, 95% CI 0.29 to 0.79). There was no significant difference at one year (0 to 10 scale: MD 0.19, 95% CI -0.22 to 0.59). Statistical heterogeneity was small to high (I2 statistic = 35% at six months, 90% at one year and 65% at two years). There were no clear differences between MID techniques and MD/OD on other primary outcomes related to functional disability (Oswestry Disability Index greater than six months postoperatively) and persistence of motor and sensory neurological deficits, though evidence on neurological deficits was limited by the small numbers of participants in the trials with neurological deficits at baseline. There was just one study for each of the sciatica-specific outcomes including the Sciatica Bothersomeness Index and the Sciatica Frequency Index, which did not need further analysis. For secondary outcomes, MID was associated with lower risk of surgical site and other infections, but higher risk of re-hospitalisation due to recurrent disc herniation. In addition, MID was associated with slightly lower quality of life (less than 5 points on a 100-point scale) on some measures of quality of life, such as some physical subclasses of the 36-item Short Form. Some trials found MID to be associated with shorter duration of hospitalisation than MD/OD, but results were inconsistent. AUTHORS' CONCLUSIONS: MID may be inferior in terms of relief of leg pain, LBP and re-hospitalisation; however, differences in pain relief appeared to be small and may not be clinically important. Potential advantages of MID are lower risk of surgical site and other infections. MID may be associated with shorter hospital stay but the evidence was inconsistent. Given these potential advantages, more research is needed to define appropriate indications for MID as an alternative to standard MD/OD.
    Cochrane database of systematic reviews (Online) 09/2014; 9(9):CD010328. DOI:10.1002/14651858.CD010328.pub2 · 6.03 Impact Factor
  • Roger Chou
    Journal of Pain 09/2014; 15(9):977. DOI:10.1016/j.jpain.2014.06.006 · 4.01 Impact Factor
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    ABSTRACT: Objectives: Despite rapidly increasing intervention, functional disability due to chronic low back pain (cLBP) has increased in recent decades. We often cannot identify mechanisms to explain the major negative impact cLBP has on patients' lives. Such cLBP is often termed nonspecific and may be due to multiple biologic and behavioral etiologies. Researchers use varied inclusion criteria, definitions, baseline assessments, and outcome measures, which impede comparisons and consensus. The purpose of this article is to disseminate the report of the National Institutes of Health (NIH) task force on research standards for cLBP. Methods: The NIH Pain Consortium charged a research task force (RTF) to draft standards for research on cLBP. The resulting multidisciplinary panel developed a 3-stage process, each with a 2-day meeting. Results: The panel recommended using 2 questions to define cLBP; classifying cLBP by its impact (defined by pain intensity, pain interference, and physical function); use of a minimal data set to describe research subjects (drawing heavily on the Patient Reported Outcomes Measurement Information System methodology); reporting "responder analyses" in addition to mean outcome scores; and suggestions for future research and dissemination. The Pain Consortium has approved these recommendations, which investigators should incorporate into NIH grant proposals. Conclusions: The RTF believes that these recommendations will advance the field, help to resolve controversies, and facilitate future research addressing the genomic, neurologic, and other mechanistic substrates of cLBP. Greater consistency in reporting should facilitate comparisons among studies and the development of phenotypes. We expect the RTF recommendations will become a dynamic document and undergo continual improvement.
    Journal of Manipulative and Physiological Therapeutics 08/2014; 37(7). DOI:10.1016/j.jmpt.2014.07.006 · 1.48 Impact Factor

Publication Stats

6k Citations
1,341.15 Total Impact Points


  • 2001–2015
    • Oregon Health and Science University
      • • Department of Medical Informatics & Clinical Epidemiology
      • • Department of Medicine
      • • Oregon Evidence-based Practice Center
      Portland, Oregon, United States
  • 2013
    • American college of Physicians
      Filadelfia, Pennsylvania, United States
  • 2010
    • Harvard Medical School
      Boston, Massachusetts, United States
  • 2009
    • Adventist University of Health Sciences
      Orlando, Florida, United States
  • 2003
    • University of Portland
      Portland, Oregon, United States