Effect of Graded Sensorimotor Retraining on Pain Intensity in Patients With Chronic Low Back Pain: A Randomized Clinical Trial.

Importance: The effects of altered neural processing, defined as altering neural networks responsible for perceptions of pain and function, on chronic pain remains unclear. Objective: To estimate the effect of a graded sensorimotor retraining intervention (RESOLVE) on pain intensity in people with chronic low back pain. Design, Setting, and Participants: This parallel, 2-group, randomized clinical trial recruited participants with chronic (>3 months) nonspecific low back pain from primary care and community settings. A total of 276 adults were randomized (in a 1:1 ratio) to the intervention or sham procedure and attention control groups delivered by clinicians at a medical research institute in Sydney, Australia. The first participant was randomized on December 10, 2015, and the last was randomized on July 25, 2019. Follow-up was completed on February 3, 2020. Interventions: Participants randomized to the intervention group (n = 138) were asked to participate in 12 weekly clinical sessions and home training designed to educate them about and assist them with movement and physical activity while experiencing lower back pain. Participants randomized to the control group (n = 138) were asked to participate in 12 weekly clinical sessions and home training that required similar time as the intervention but did not focus on education, movement, and physical activity. The control group included sham laser and shortwave diathermy applied to the back and sham noninvasive brain stimulation. Main Outcomes and Measures: The primary outcome was pain intensity at 18 weeks, measured on an 11-point numerical rating scale (range, 0 [no pain] to 10 [worst pain imaginable]) for which the between-group minimum clinically important difference is 1.0 point. Results: Among 276 randomized patients (mean [SD] age, 46 [14.3] years; 138 [50%] women), 261 (95%) completed follow-up at 18 weeks. The mean pain intensity was 5.6 at baseline and 3.1 at 18 weeks in the intervention group and 5.8 at baseline and 4.0 at 18 weeks in the control group, with an estimated between-group mean difference at 18 weeks of -1.0 point ([95% CI, -1.5 to -0.4]; P = .001), favoring the intervention group. Conclusions and Relevance: In this randomized clinical trial conducted at a single center among patients with chronic low back pain, graded sensorimotor retraining, compared with a sham procedure and attention control, significantly improved pain intensity at 18 weeks. The improvements in pain intensity were small, and further research is needed to understand the generalizability of the findings. Trial Registration: ANZCTR Identifier: ACTRN12615000610538.

Combined education and patient-led goal setting intervention reduced chronic low back pain disability and intensity at 12 months: a randomised controlled trial.

BACKGROUND: One model of care that has not been tested for chronic low back pain (LBP) is patient-led goal setting. We aimed to compare the clinical effectiveness and healthcare use of a patient-led goal setting approach (intervention) with simple advice to exercise (control) over 12 months. METHODS: An assessor-blinded randomised controlled trial. Intervention was education combined with patient-led goal setting compared with a control group receiving a standardised exercise programme. The primary outcomes were back pain disability and pain intensity. Secondary outcomes were quality of life, kinesiophobia, self-efficacy, depression, anxiety and stress. Outcomes and healthcare use were assessed immediately post-treatment (2 months) and after 4 and 12 months. Analysis was by intention to treat. RESULTS: Seventy-five patients were randomly assigned to either the intervention (n=37) or the control (n=38) group. Using linear mixed model analyses, adjusted mean changes in primary outcomes of disability and pain intensity were greater in the intervention group than in the control group (disability post-treatment: p<0.05). These differences were clinically meaningful. Mean differences in all secondary measures were greater in the intervention group than in the control group (p<0.05). There was no difference in healthcare use between groups over 12 months. CONCLUSION: A patient-led goal setting intervention was significantly more effective than advice to exercise for improving outcomes in disability, pain intensity, quality of life, self-efficacy and kinesiophobia in chronic LBP. These improvements were maintained at 12 months. Smaller effects were seen in measures of depression, anxiety and stress. TRIAL REGISTRATION NUMBER: ACTRN12614000830695.

The reliability of eyetracking to assess attentional bias to threatening words in healthy individuals.

Eyetracking is commonly used to investigate attentional bias. Although some studies have investigated the internal consistency of eyetracking, data are scarce on the test-retest reliability and agreement of eyetracking to investigate attentional bias. This study reports the test-retest reliability, measurement error, and internal consistency of 12 commonly used outcome measures thought to reflect the different components of attentional bias: overall attention, early attention, and late attention. Healthy participants completed a preferential-looking eyetracking task that involved the presentation of threatening (sensory words, general threat words, and affective words) and nonthreatening words. We used intraclass correlation coefficients (ICCs) to measure test-retest reliability (ICC > .70 indicates adequate reliability). The ICCs(2, 1) ranged from -.31 to .71. Reliability varied according to the outcome measure and threat word category. Sensory words had a lower mean ICC (.08) than either affective words (.32) or general threat words (.29). A longer exposure time was associated with higher test-retest reliability. All of the outcome measures, except second-run dwell time, demonstrated low measurement error (<6%). Most of the outcome measures reported high internal consistency (α > .93). Recommendations are discussed for improving the reliability of eyetracking tasks in future research.

An embedded randomised controlled trial of a Teaser Campaign to optimise recruitment in primary care.

BACKGROUND: Marketing communication and brand identity is a fundamental principle of advertising and end-user engagement. Health researchers have begun to apply this principle to trial recruitment in primary care. The aim of this study was to evaluate whether a Teaser Campaign using a series of postcards in advance of a conventional mail-out increases the number of primary care clinics that engage with a clinical trial. METHODS: Embedded randomised recruitment trial across primary care clinics (general practitioners and physiotherapists) in the Sydney metropolitan area. Clinics in the Teaser Campaign group received a series of branded promotional postcards in advance of a standard letter inviting them to participate in a clinical trial. Clinics in the Standard Mail group did not receive the postcards. RESULTS: From a total of 744 clinics that were sent an invitation letter, 46 clinics in the Teaser Campaign group and 40 clinics in the Standard Mail group responded (11.6% total response rate). There was no between-group difference in the odds of responding to the invitation letter (odds ratio = 1.18, 95% confidence interval = 0.75-1.85, p = 0.49). For physiotherapy clinics and general practice clinics, the odds ratios were 1.43 (confidence interval = 0.82-2.48, p = 0.21) and 0.77 (confidence interval = 0.34-1.75, p = 0.54), respectively. CONCLUSION: A Teaser Campaign using a series of branded promotional postcards did not improve clinic engagement for a randomised controlled trial in primary care.

Estimating the Risk of Chronic Pain: Development and Validation of a Prognostic Model (PICKUP) for Patients with Acute Low Back Pain.

BACKGROUND: Low back pain (LBP) is a major health problem. Globally it is responsible for the most years lived with disability. The most problematic type of LBP is chronic LBP (pain lasting longer than 3 mo); it has a poor prognosis and is costly, and interventions are only moderately effective. Targeting interventions according to risk profile is a promising approach to prevent the onset of chronic LBP. Developing accurate prognostic models is the first step. No validated prognostic models are available to accurately predict the onset of chronic LBP. The primary aim of this study was to develop and validate a prognostic model to estimate the risk of chronic LBP. METHODS AND FINDINGS: We used the PROGRESS framework to specify a priori methods, which we published in a study protocol. Data from 2,758 patients with acute LBP attending primary care in Australia between 5 November 2003 and 15 July 2005 (development sample, n = 1,230) and between 10 November 2009 and 5 February 2013 (external validation sample, n = 1,528) were used to develop and externally validate the model. The primary outcome was chronic LBP (ongoing pain at 3 mo). In all, 30% of the development sample and 19% of the external validation sample developed chronic LBP. In the external validation sample, the primary model (PICKUP) discriminated between those who did and did not develop chronic LBP with acceptable performance (area under the receiver operating characteristic curve 0.66 [95% CI 0.63 to 0.69]). Although model calibration was also acceptable in the external validation sample (intercept = -0.55, slope = 0.89), some miscalibration was observed for high-risk groups. The decision curve analysis estimated that, if decisions to recommend further intervention were based on risk scores, screening could lead to a net reduction of 40 unnecessary interventions for every 100 patients presenting to primary care compared to a "treat all" approach. Limitations of the method include the model being restricted to using prognostic factors measured in existing studies and using stepwise methods to specify the model. Limitations of the model include modest discrimination performance. The model also requires recalibration for local settings. CONCLUSIONS: Based on its performance in these cohorts, this five-item prognostic model for patients with acute LBP may be a useful tool for estimating risk of chronic LBP. Further validation is required to determine whether screening with this model leads to a net reduction in unnecessary interventions provided to low-risk patients.

Protective and Harmful Effects of Physical Activity for Low Back Pain: A Protocol for the AUstralian Twin BACK Pain (AUTBACK) Feasibility Study.

Low back pain (LBP) is a major health problem globally, but approaches to prevention are not yet clearly identified because modifiable risk factors are not well established. Although physical activity is one promising modifiable risk factor, it is still not known what types and doses of physical activity are protective or harmful for LBP. The aim of this study is to establish the feasibility of a definitive cohort study that will investigate the effects of different types and doses of physical activity on the risk of developing recurrent LBP while accounting for genetic factors. This will be a pilot longitudinal twin study and twins will be recruited from the Australian Twin Registry, and will be followed over 1 year. Thirty adult complete twin pairs with a history of LBP, but symptom free at recruitment, will be included. Data on physical activity (predictor) will be collected using four questionnaires and an objective measure (accelerometer) at baseline and at 6-month follow-up. Twins will also complete an additional physical activity questionnaire monthly. Data on LBP (outcome) will be collected at baseline and weekly. Data will be collected using short message service (SMS) and email. We will keep records of the recruitment rate, follow-up rate, and completeness of data. Barriers to completing the study will be investigated. The results of this study will inform the design and implementation of a future definitive study, which will help to clarify the effects of different types and doses of physical activity on the risk of developing recurrent LBP.

Does physical activity moderate the relationship between depression symptomatology and low back pain? Cohort and co-twin control analyses nested in the longitudinal study of aging Danish twins (LSADT).

PURPOSE: To investigate whether depression symptomatology is associated with low back pain (LBP) in twins aged 70+ and whether this effect depends on a person's physical activity (PA) status. METHODS: This prospective cohort and nested case-control study used a nationally representative sample of twins. Data on depression symptomatology (modified Cambridge Mental Disorders Examination) and self-reported PA were obtained from the Longitudinal Study of Aging Danish Twins using twins without LBP at baseline. Associations between depression symptomatology (highest quartile) at baseline and LBP two years later were investigated using logistic regression analyses adjusted for sex. To examine the moderating effect of PA, we tested its interaction with depression. Associations were analysed using the complete sample of 2446 twins and a matched case-control analysis of 97 twin pairs discordant for LBP at follow-up. Odds ratios (OR) with 95% confidence intervals (CI) were calculated. RESULTS: Using the whole sample, high depression scores were associated with an increased probability of LBP (OR 1.56, 95% CI 1.22-1.99, P ≤ 0.01). There was no statistically significant interaction of light PA and depression symptomatology (OR 0.78, 95% CI 0.46-1.35, P = 0.39) and strenuous PA and depression symptomatology (0.84, 95% CI 0.50-1.41, P = 0.51). The case-control analysis showed similar ORs, although statistically insignificant. CONCLUSIONS: High depression symptomatology predicted incident LBP. This effect is supposedly not attributable to genetic or shared environmental factors. Physical activity did not moderate the effect of depression symptomatology on LBP.

Emotional distress drives health services overuse in patients with acute low back pain: a longitudinal observational study.

PURPOSE: To determine whether emotional distress reported at the initial consultation affects subsequent healthcare use either directly or indirectly via moderating the influence of symptoms. METHODS: Longitudinal observational study of 2891 participants consulting primary care for low back pain. Negative binomial regression models were constructed to estimate independent effects of emotional distress on healthcare use. Potential confounders were identified using directed acyclic graphs. RESULTS: After the initial consultation, participants had a mean (SD) of one (1.2) visit for back pain over 3 months, and nine (14) visits for back pain over 12 months. Higher reports of anxiety during the initial consultation led to increased short-term healthcare use (IRR 1.06, 95 % CI 1.01-1.11) and higher reports of depression led to increased long-term healthcare use (IRR 1.04, 95 % CI 1.02-1.07). The effect sizes suggest that a patient with a high anxiety score (8/10) would consult 50 % more frequently over 3 months, and a person with a high depression score (8/10) would consult 30 % more frequently over 12 months, compared to a patient with equivalent pain and disability and no reported anxiety or depression. CONCLUSIONS: Emotional distress in the acute stage of low back pain increased subsequent consultation rates. Interventions that target emotional distress during the initial consultation are likely to reduce costly and potentially inappropriate future healthcare use for patients with non-specific low back pain.

No Effect of Acupuncture in the Relief of Delayed-Onset Muscle Soreness: Results of a Randomized Controlled Trial.

BACKGROUND: Delayed-onset muscle soreness (DOMS) is a common symptom in people participating in exercise, sport, or recreational physical activities. Several remedies have been proposed to prevent and alleviate DOMS. DESIGN AND METHODS: A five-arm randomized controlled study was conducted to examine the effects of acupuncture on eccentric exercise-induced DOMS of the biceps brachii muscle. Participants were recruited through convenience sampling of students and general public. Participants were randomly allocated to needle, laser, sham needle, sham laser acupuncture, and no intervention. Outcome measures included pressure pain threshold (PPT), pain intensity (visual analog scale), and maximum isometric voluntary force. RESULTS: Delayed-onset muscle soreness was induced in 60 participants (22 females, age 23.6 ± 2.8 years, weight 66.1 ± 9.6 kg, and height 171.6 ± 7.9 cm). Neither verum nor sham interventions significantly improved outcomes within 72 hours when compared with no treatment control (P > 0.05). CONCLUSIONS: Acupuncture was not effective in the treatment of DOMS. From a mechanistic point of view, these results have implications for further studies: (1) considering the high-threshold mechanosensitive nociceptors of the muscle, the cutoff for PPT (5 kg/cm) chosen to avoid bruising might have led to ceiling effects; (2) the traditional acupuncture regimen, targeting muscle pain, might have been inappropriate as the DOMS mechanisms seem limited to the muscular unit and its innervation. Therefore, a regionally based regimen including an intensified intramuscular needling (dry needling) should be tested in future studies, using a higher cutoff for PPT to avoid ceiling effects.

Differences in Gait Performance, Quadriceps Strength, and Physical Activity Between Fallers and Nonfallers in Women with Osteoporosis.

The present study should reveal differences in gait performance, quadriceps strength, and physical activity (PA) between fallers and nonfallers in women with osteoporosis. Forty-one women with osteoporosis (17 fallers, 24 nonfallers) participated. Gait analysis shows that fallers were walking with a slower walking speed (-9%, p = .033) and had a shorter stride length (-7%, p = .039). Moreover, fallers showed a decreased ankle power generation (-18%, p = .045). The quadriceps strength was decreased by 24% for fallers (p = .005) while PA showed no significant differences. Although a decrease in ankle power generation could have an effect on floor clearance for limb advancement in the swing phase, the causal relationship between spatiotemporal parameters (walking speed, stride length) and walking ankle joint power generation remains unknown and warrants further investigation. In conclusion, walking speed, stride length, ankle power generation, and quadriceps strength can be used to differentiate between fallers and nonfallers in women with osteoporosis.

Elevated levels of GABA+ in migraine detected using (1) H-MRS.

γ-Aminobutyric acid (GABA) has been implicated in several pain conditions, yet no study has systematically evaluated GABA levels in migraine using (1) H-MRS. The accurate detection, separation and quantification of GABA in individuals with migraine could elucidate the role of this neurotransmitter in migraine pathophysiology. Such information may eventually be useful in the diagnosis and development of more effective treatments for migraine. The aims of this study were therefore to compare the concentration of GABA+ in individuals with migraine with that in asymptomatic individuals, and to determine the diagnostic potential of GABA+ in the classification of those with or without migraine. In this case-control study, GABA+ levels in the brain were determined in 19 participants with migraine and 19 matched controls by (1) H-MRS using Mescher-Garwood point-resolved spectroscopy (MEGA-PRESS) sequence. The diagnostic accuracy of GABA+ for the detection of migraine and the optimal cut-off value were determined by receiver operating characteristic analysis. GABA+ levels were significantly higher (p = 0.002) in those with migraine [median, 1.41 institutional units (IU); interquartile range, 1.31-1.50 IU] than in controls (median, 1.18 IU; interquartile range, 1.12-1.35 IU). The GABA+ concentration appears to have good accuracy for the classification of individuals with or without migraine [area under the curve (95% confidence interval), 0.837 (0.71-0.96); p < 0.001]. The optimal GABA+ cut-off value for migraine was 1.30 IU, with a sensitivity of 84.2%, specificity of 68.4% and positive likelihood ratio of +2.67. The outcomes of this study suggest altered GABA metabolism in migraine. These results add to the scarce evidence on the putative role of GABA in migraine and provide a basis to further explore the causal relationship between GABA+ and the pathophysiology of migraine. This study also demonstrates that GABA+ concentration has good diagnostic accuracy for migraine. These findings offer new research and practice directions for migraine diagnosis.

Movement restriction does not modulate sensory and perceptual effects of exercise-induced arm pain.

BACKGROUND: Movement restriction has been proposed as an important modulator of changes in sensory and perceptual function and motor imagery performance that are observed in musculoskeletal pain syndromes. There are no empirical data to support this view. PURPOSE: The primary objective of this experiment was to determine the effects of movement restriction on local and widespread sensory, perceptual and motor imagery changes after exercise-induced muscular pain. Further objectives were to investigate whether changes in sensory perception are correlated with pain intensity and tactile acuity or motor imagery performance. METHODS: In forty healthy volunteers, delayed onset muscle soreness (DOMS) of the non-dominant elbow flexors was induced using eccentric contractions until exhaustion. Participants were then randomised into two groups: a movement restriction group (wearing a sling) or a control group (not wearing a sling). Sensory and perceptual functions were measured using a range of sensory tests and a motor imagery performance task (left/right limb judgements). RESULTS: Movement restriction did not modulate any of the measures. We found concurrent mechanical hypoesthesia (p < 0.01), reduced tactile acuity (p = 0.02) and pressure hyperalgesia (p < 0.01) at the painful side. We found evidence of widespread pressure hyperalgesia. Impaired tactile acuity was associated with a decrease in pain threshold to pressure (r = -0.34, p = 0.03). Motor imagery performance was unchanged (p > 0.35) by pain or movement restriction. CONCLUSION: Short-term movement restriction did not influence local and widespread sensory changes induced by experimentally induced muscular pain.

Heavy domestic, but not recreational, physical activity is associated with low back pain: Australian Twin low BACK pain (AUTBACK) study.

PURPOSE: To evaluate the association between domestic and recreational physical activity (PA) and low back pain (LBP) after adjusting for genetic and environmental influences. METHODS: Twins were recruited through the Australian twin registry. LBP prevalence and domestic (vigorous gardening/heavy yard work) and recreational (light walking, moderate/vigorous) PA were assessed by a validated questionnaire. Associations were analysed using a cross-sectional analysis of the complete sample of 486 twins, including a matched case-control analysis of 69 twin pairs discordant for LBP. Logistic regression and the lincom post-estimation method were used for the analysis. Odds ratios (OR) with 95 % confidence intervals (CIs) were calculated. RESULTS: The case-control analysis showed that LBP was significantly associated with heavy domestic PA (OR 2.88, 95 % CI 1.29-6.43), whereas no significant association was found with any form of recreational PA. The results of the lincom command indicated that being engaged in both heavy domestic and recreational PA (light walking or moderate/vigorous) was associated with a significantly increased probability of LBP compared with being engaged only in recreational PA (light walking or moderate/vigorous, ORs 3.48-4.22). Using the whole sample, we found weaker associations but in the same direction. CONCLUSIONS: We found evidence that heavy domestic PA is associated with an increased probability of LBP, and the combination of heavy domestic and recreational PA might increase the probability of LBP more so than heavy domestic or recreational PA alone. Associations being greater when using the co-twin case-control analysis indicate that genetic and environmental factors influence the relationship between PA and LBP, and demonstrate the value of a twin design.

Does poor sleep quality lead to increased low back pain the following day?

OBJECTIVES: This study explored the relationship between sleep quality and next-day pain intensity for people with low back pain and investigated whether there was any evidence that this relationship was causal. METHODS: We conducted a secondary analysis of an observational study that investigated sleep quality in people with low back pain. People with low back pain were recruited from primary care and the community. Sleep quality was measured with subjective (self-report) and objective (polysomnography (PSG)) measures. PSG analysis classifies sleep into stages, of which slow-wave sleep (SWS) is thought to have a key role in maintaining or increasing pain intensity. We drew directed acyclic graphs to identify possible confounders of the relationship between both measures of sleep quality, and pain intensity. We constructed two linear regression models to explore the effect of subjective and objective sleep quality on next-day pain intensity before and after confounder adjustment. RESULTS: Thirty-nine participants were included in the study. For participants with low back pain, self-reported better quality sleep ß=-0.38 (95% CI -0.63 to -0.13), or spending a greater proportion of time in SWS ß=-0.12 (95% CI -0.22 to -0.02) was associated with lower next day pain intensity. After confounder adjustment, the effect reduced and was no longer significant for either self-reported ß=-0.18 (95% CI -0.46 to 0.10), or SWS ß=-0.08 (95% CI -0.18 to 0.03). CONCLUSIONS: Sleep quality, whether measured by self-report or proportion of time in SWS, was associated with next day pain intensity for people with low back pain. However, this relationship is likely to be confounded and therefore not likely to be causal.

Making exercise count: Considerations for the role of exercise in back pain treatment.

INTRODUCTION: Chronic low back pain (CLBP) is pain that has persisted for greater than three months. It is common and burdensome and represents a significant proportion of primary health presentations. For the majority of people with CLBP, a specific nociceptive contributor cannot be reliably identified, and the pain is categorised as 'non-specific'. Exercise therapy is recommended by international clinical guidelines as a first-line treatment for non-specific CLBP. AIM: This comprehensive review aims to synthesise and appraise the current research to provide practical, evidence-based guidance concerning exercise prescription for non-specific CLBP. We discuss detailed initial assessment and being informed by patient preferences, values, expectations, competencies and goals. METHODS: We searched the Cochrane Database of Systematic Reviews, PubMed and the Physiotherapy Evidence Database (PEDro) using broad search terms from January 2000 to March 2021, to identify the most recent clinical practice guidelines, systematic reviews and randomised controlled trials on exercise for CLBP. RESULTS/DISCUSSION: Systematic reviews show exercise is effective for small, short-term reductions in pain and disability, when compared with placebo, usual care, or waiting list control, and serious adverse events are rare. A range of individualised or group-based exercise modalities have been demonstrated as effective in reducing pain and disability. Despite this consensus, controversies and significant challenges remain. CONCLUSION: To promote recovery, sustainable outcomes and self-management, exercise can be coupled with education strategies, as well as interventions that enhance adherence, motivation and patient self-efficacy. Clinicians might benefit from intentionally considering their own knowledge and competencies, potential harms of exercise and costs to the patient. This comprehensive review provides evidence-based practical guidance to health professionals who prescribe exercise for people with non-specific CLBP.

Producing Clinically Meaningful Reductions in Disability: A Causal Mediation Analysis of a Patient Education Intervention.

Patient education is recommended as first-line care for low back pain (LBP), although its efficacy for providing clinically meaningful reductions in disability has been questioned. One way to improve treatment effects is to identify and improve targeting of treatment mechanisms. We conducted a pre-planned causal mediation analysis of a randomized, placebo-controlled trial investigating the effectiveness of patient education for patients with acute LBP. 202 patients who had fewer than six-weeks' duration of LBP and were at high-risk of developing chronic LBP completed two, one-hour treatment sessions of either intensive patient education, or placebo patient education. 189 participants provided data for the outcome self-reported disability at three-months and the mediators, pain self-efficacy, pain catastrophizing, and back beliefs at one-week post treatment. This causal mediation analysis found that pain catastrophizing (mediated effect, -0.64; 95% Confidence Interval [CI], -1.31 to -0.15) and back beliefs (mediated effect, -0.51; 95% CI, -1.15 to -0.02) partly explained the effect of patient education on disability but pain self-efficacy did not (mediated effect, -0.40; 95% CI -1.13 to 0.28). Considering the mediator-outcome relationship, patient education would need to induce an 8 point difference on the pain self-efficacy questionnaire (0-60); an 11 point difference on the back beliefs questionnaire (9-45); and a 21 point difference on the pain catastrophizing scale (0-52) to achieve a minimally clinically important difference of 2 points on the Roland Morris Disability Questionnaire (0-24). PERSPECTIVE: Understanding the mechanisms of patient education can inform how this treatment can be adapted to provide clinically meaningful reductions in disability. Our findings suggest that adapting patient education to better target back beliefs and pain self-efficacy could result in clinically meaningful reductions in disability whereas the role of pain catastrophizing in acute LBP is less clear.

[GRADE Guidelines: 19. Assessing the certainty of evidence in the importance of outcomes or values and preferences: Risk of bias and indirectness]. / GRADE-Leitlinien: 19. Bewertung der Vertrauenswürdigkeit der Evidenz für die Bedeutung von Endpunkten oder Werten und Präferenzen ­ Risiko für Bias und Indirektheit.

OBJECTIVES: The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) working group defines patient values and preferences as the relative importance patients place on the main health outcomes. We provide GRADE guidance for assessing the risk of bias and indirectness domains for certainty of evidence about the relative importance of outcomes. STUDY DESIGN AND SETTING: We applied the GRADE domains to rate the certainty of evidence in the importance of outcomes to several systematic reviews, iteratively reviewed draft guidance and consulted GRADE members and other stakeholders for feedback. RESULTS: This is the first of two articles. A body of evidence addressing the importance of outcomes starts at "high certainty"; concerns with risk of bias, indirectness, inconsistency, imprecision, and publication bias lead to downgrading to moderate, low, or very low certainty. We propose the following subdomains of risk of bias: selection of the study population, missing data, the type of measurement instrument, and confounding; we have developed items for each subdomain. The population, intervention, comparison, and outcome elements associated with the evidence determine the degree of indirectness. CONCLUSION: This article provides guidance and examples for rating the risk of bias and indirectness for a body of evidence summarizing the importance of outcomes.

Feeling reassured after a consultation does not reduce disability or healthcare use in people with acute low back pain: a mediation analysis of a randomised trial.

QUESTION: Does feeling reassured after a consultation reduce future disability or healthcare use in people with acute low back pain (LBP)? DESIGN: Mediation analysis of a randomised, sham-controlled trial. PARTICIPANTS: Two hundred and two people with acute LBP at above average risk (high risk) of developing chronic LBP. INTERVENTION: All participants received guideline-based care from their usual clinician. Participants received two additional 1-hour sessions of patient education focused on emphasising the benign nature of LBP or sham patient education that included active listening only. OUTCOME MEASURES: The two primary outcomes for this study were self-reported disability and healthcare use. The mediator was feeling reassured that LBP was not caused by serious illness. RESULTS: Data from 194 (96%) participants and 178 (88%) participants were included in the analysis for disability and healthcare use outcome models, respectively. Feeling reassured did not mediate the effect of the intervention on disability (indirect effect -0.23, 95% CI -0.71 to 0.18) or healthcare use (indirect effect 0.00, 95% CI -0.04 to 0.04). Patient education intervention increased feeling reassured (1.14 points, 95% CI 0.43 to 1.85) compared with sham patient education. However, the mediator (ie, feeling reassured) did not reduce disability (-0.20 points, 95% CI -0.58 to 0.19) or healthcare use (OR 1.09, 95% CI 0.98 to 1.21). CONCLUSION: Feeling reassured after a consultation did not lead to improvements in disability and healthcare use for people with acute LBP. Clinicians should reflect on the time that they allocate to reassuring their patients and consider reallocating time to other aspects of the consultation that could reduce disability and future healthcare use. TRIAL REGISTRATION: ACTRN12612001180808, study protocol https://osf.io/4tfaz/.

Do people with acute low back pain have an attentional bias to threat-related words?

OBJECTIVES: It has been hypothesised that attentional bias to environmental threats can contribute to persistent pain. It is unclear whether people with acute low back pain (LBP) have an attentional bias to environmental threats. We investigated if attentional bias of threat related words is different in people with acute LBP and pain-free controls. METHODS: People with acute LBP and pain-free people completed a free viewing eye tracking task. Participants were simultaneously presented with two words, a threat related word and a neutral control word. Threat related words were general threat, affective pain and sensory pain. We conducted linear mixed models to detect differences between acute LBP and pain-free participants on five eye tracking outcome measures (dwell time, first fixation, latency to first fixation, first run dwell time and number of fixations). We calculated absolute reliability, (standard error of measure), and relative reliability (intraclass correlation coefficients [ICC 2,1]) for each eye tracking outcome measures. RESULTS: We recruited 65 people with acute LBP and 65 pain-free controls. Participants with acute LBP had a higher proportion of fixations towards the affective pain words (M=0.5009, 95% CI=0.4941, 0.5076) than the pain-free controls had (M=0.4908, 95% CI=0.4836, 0.4979), mean between group difference = -0.0101, 95% CI [-0.0198, -0.0004], p=0.0422. There was no difference between acute LBP and pain-free controls for the remaining eye tracking outcome measures (all p>0.05). The only outcome measure that had an ICC of more than 0.7 was the latency to first fixation (affective pain words ICC=0.73, general threat words ICC=0.72). CONCLUSIONS: When compared with pain-free controls, people with acute LBP looked more often at affective pain words relative to neutral control words. This may indicate a form of engagement bias for people with acute LBP. Attentional bias was not consistent across outcome measures or word groups. Further research is needed to investigate the potential role of attentional bias in the development of persistent pain.

The RESOLVE Trial for people with chronic low back pain: statistical analysis plan.

BACKGROUND: Statistical analysis plans describe the planned data management and analysis for clinical trials. This supports transparent reporting and interpretation of clinical trial results. This paper reports the statistical analysis plan for the RESOLVE clinical trial. The RESOLVE trial assigned participants with chronic low back pain to graded sensory-motor precision training or sham-control. RESULTS: We report the planned data management and analysis for the primary and secondary outcomes. The primary outcome is pain intensity at 18-weeks post randomization. We will use mixed-effects models to analyze the primary and secondary outcomes by intention-to-treat. We will report adverse effects in full. We also describe analyses if there is non-adherence to the interventions, data management procedures, and our planned reporting of results. CONCLUSION: This statistical analysis plan will minimize the potential for bias in the analysis and reporting of results from the RESOLVE trial. TRIAL REGISTRATION: ACTRN12615000610538 (https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=368619).