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Patient blinding is a critical feature of double-blind placebo-controlled randomized controlled trials (RCTs). Yet, very little is known about practices for assessing and reporting blinding in chronic pain trials. We examined the rates and predictors of assessing blinding and its success in pharmacological RCTs for chronic pain. Four-hundred eight trials (n = 103,983 participant) were identified via a systematic search between 2006 and 2016. Only 23 RCTs (5.6%) reported assessing patient blinding. Larger sample size, reference to a CONSORT statement, and pharmaceutical sponsorship were associated with lower rates of assessing blinding. A meta-analysis of the available data using Bang's Blinding Index indicated that blinding was not successful when combined across studies (g = 1.12, 95% confidence interval .92-2.01). Moderator analysis revealed that higher rates of adverse events and larger treatment effect sizes were associated with worse blinding outcomes, whereas including "don't know" responses seemed to improve blinding. Overall then, blinding is rarely reported and often fails in RCTs of pharmacological interventions for chronic pain. To address this finding, we recommend that all researchers conducting RCTs for chronic pain assess and report on the status of patient blinding when reporting the trial outcome. PERSPECTIVE: This meta-analysis examined patient blinding in pharmacological RCTs of chronic pain. The results indicated that blinding is rarely assessed and often fails. Some study characteristics were associated with lower rates of assessing blinding and its success, for example, pharmaceutical sponsorship and side effects. Implications and recommendations for chronic pain RCTs are discussed. [ABSTRACT FROM AUTHOR]

Persistent pain in young people in the community is common, but individuals vary in how much pain impacts daily life. Information-processing accounts of chronic pain partly attribute the fear and avoidance of pain, as well as associated interference, to a set of involuntary biases, including the preferential allocation of attention resources toward potential threats. Far less research has focused on the role of voluntary goal-directed attention control processes, the ability to flexibly direct attention toward and away from threats, in explaining pain-associated interference. Using a visual search task, we explored a poor attention control account of pain interference in young people with persistent pain from the community. One hundred and forty five young people aged 16 to 19 years were categorized into three groups: non-chronic pain (n = 68), low-interfering persistent pain (n = 40), and moderate- to high-interfering persistent pain (n = 22). We found that only adolescents with moderate-to high-interfering persistent pain but not the other two groups of adolescents were affected by a search task preceded by a pain face (compared to a neutral face), but this within-group difference emerged only under low perceptual load conditions. Because low perceptual load conditions are thought to require more strategic attention resources to suppress the interfering effects of pain face primes, our findings are consistent with a poor attention control account of pain interference in young people. Analyses further showed that these differences in task performance were not explained by confounding effects of anxiety. If replicated, these findings may have implications for understanding and managing the pain-associated disability in adolescents with chronic pain. PERSPECTIVE: Young people with moderately and highly interfering pain responded slower on an easy search task after seeing a pain face than after seeing a neutral face. If replicated, these findings could mean that boosting the ability to control attention toward and away from threatening cues is an effective strategy for managing interference from pain. [ABSTRACT FROM AUTHOR]

Despite widespread use as a chronic pain management strategy, pacing has been linked with higher levels of pain and disability. A recent meta-analysis found a positive correlation between existing measures of pacing and avoidance, which may partially account for these poorer outcomes. A measure was developed to differentiate pacing from avoidance by emphasizing non-pain-contingent pacing behaviors and nonavoidance of pain. A sample of 283 adults with chronic pain completed the Non-Avoidant Pacing Scale (NAPS) and existing measures of pacing, avoidance, pain, and physical and psychological functioning. Exploratory factor analysis of 10 items (subsample 1, n = 141) suggested two 4-item factors: planned pacing behaviors and pacing through flare ups. Confirmatory factor analysis of 8 items (subsample 2, n = 142) revealed satisfactory fit (goodness-of-fit index .947, comparative fit index .964). The pattern of correlations between each factor and avoidance and key outcomes suggests that the NAPS total scale (ɑ = .819) captures key pacing behaviors and differentiates pacing from avoidance. Unlike existing measures, the NAPS was not positively correlated with avoidance and was associated with better psychological functioning across affective and cognitive domains. The NAPS allows researchers and clinicians to assess the role of pacing in chronic pain management without artefactual overlap with avoidance. PERSPECTIVE: The NAPS assesses activity pacing in chronic pain without artefactual overlap with avoidance. Associations were found between more frequent pacing, as measured by the NAPS, and better psychological functioning. Clearly differentiating pacing from avoidance allows for accurate assessment of the role of pacing in chronic pain management. [ABSTRACT FROM AUTHOR]

Little is known about the long-term outcomes of emerging Internet-delivered pain management programs. The current study reports the 12- and 24-month follow-up data from a randomized controlled trial (n = 490) of an Internet-delivered pain management program, the Pain Course. The initial results of the trial to the 3-month follow-up have been reported elsewhere. There were significant improvements in disability, depression, anxiety, and pain levels across 3 treatment groups receiving different levels of clinician support compared with a treatment as the usual control. No marked or significant differences were found between the treatment groups either after treatment or at the 3-month follow-up. The current study obtained long-term follow-up data from 78% and 79% of participants (n = 397) at the 12-month and 24-month follow-up marks, respectively. Clinically significant decreases (average percent reduction; Cohen's d effect sizes) were maintained at the 12- and 24-month follow-ups for disability (average reduction ≥27%; d ≥ .67), depression (average reduction ≥36%; d ≥ .80), anxiety (average reduction ≥38%; d ≥ .66), and average pain levels (average reduction ≥21%; d ≥ .67). No marked or consistent differences were found among the 3 treatment groups. These findings suggest that the outcomes of Internet-delivered programs may be maintained over the long term. PERSPECTIVE: This article presents the long-term outcome data of an established Internet-delivered pain management program for adults with chronic pain. The clinical improvements observed during the program were found to be maintained at the 12- and 24-month follow-up marks. This finding indicates that these programs can have lasting clinical effects. [ABSTRACT FROM AUTHOR]

This review investigated whether youth exhibit attention or interpretation biases toward pain-related information and whether such biases are more pronounced in youth with chronic pain. Three databases were searched to identify studies that assessed attention or interpretation biases using an accepted experimental paradigm. Ten studies were identified, 8 examining attentional biases and 2 examining interpretation biases. As in the adult literature, there was no evidence of attentional biases toward pain in youth without chronic pain. Three studies investigating youth without chronic pain found evidence for relationships between catastrophizing or anxiety and indicators of vigilance or avoidance (in 2 cases, for youth with low self-reported attentional control). For attentional biases, 5 studies compared youth with and without chronic pain. Two of these studies measured cortical correlates and found evidence of neurologic activity indicating a bias in orienting to pain-related stimuli. Three studies examined biases toward pain-related words or pictures. Of those, 2 found evidence of biases at subliminal presentation times, indicating vigilance (although 1 only after a stressful task). For supraliminal presentations, 1 study found evidence of avoidance, one of difficulty disengaging, and one of general slowing of responses. Only 1 study compared youth with and without pain for interpretation bias in adolescents, and interpretation biases were greater for youth with chronic pain. As with attention, no evidence for interpretation biases were found in youth without chronic pain. Overall, there is weak evidence to support vigilance in youth with chronic pain compared with those without. However, whether pain affects the subsequent deployment of attention is unclear. There is no evidence for biases toward pain in youth without chronic pain, but evidence suggests that anxiety or catastrophizing and attentional control may moderate pain-related attentional biases. There is also weak evidence of interpretation bias in youth with chronic pain compared with those without.Perspective: Children without chronic pain do not show interpretation or attention biases toward pain-related stimuli. However, there is weak evidence for the presence of attention biases, characterized by vigilance toward pain-related stimuli and pain-related interpretation bias in children with chronic pain compared with those without. [ABSTRACT FROM AUTHOR]

Nocebo effects in pain (nocebo hyperalgesia) have received significant attention recently, with negative expectancies and anxiety proposed to be explanatory factors. While both expectancy and anxiety can bias attention, attention has been rarely explored as a potential mechanism involved in nocebo hyperalgesia. The present study aimed to explore whether attention bias modification (ABM) using an immersive, ecologically valid VR paradigm successfully induced attention biases (AB) and subsequently influenced nocebo hyperalgesia. One-hundred and two healthy participants were randomised in a 2 (AB training: towards vs. away from pain) x 2 (nocebo condition: nocebo vs. control) design. Pain-related AB was successfully changed by the VR paradigm as measured by reaction time and gaze, with moderate to large effects. Participants then completed either a nocebo instruction and conditioning procedure (nocebo paradigm) or a matched control procedure. The primary outcome was self-reported pain intensity. Secondary outcomes were attention bias and self-reports of expectancy, anticipatory anxiety, and state anxiety. The nocebo paradigm induced significantly greater pain expectancy, anticipatory anxiety and pain intensity during the test phase for the nocebo group compared to control. Pain expectancy also fully mediated the effect of the nocebo group on nocebo hyperalgesia and anticipatory anxiety in separate models. ABM did not, however, affect nocebo hyperalgesia or pain expectancy, casting doubt on the potential for ABM to inoculate against nocebo hyperalgesia. Unexpected effects of ABM were observed for state anxiety and anticipatory anxiety, whereby training away from pain exacerbated each, which necessitates further exploration. PERSPECTIVE: This article tests the efficacy of a novel attention bias modification paradigm, designed in virtual reality, for inducing pain-related biases, and whether these biases exacerbate or inoculate against nocebo hyperalgesia. While pain-related biases were successfully induced, there was no relationship with the strength of induced nocebo hyperalgesia., (Copyright © 2024 United States Association for the Study of Pain, Inc. Published by Elsevier Inc. All rights reserved.)

Nocebo effects in pain (nocebo hyperalgesia) have been thoroughly researched, and negative expectancies have been proposed as a key factor in causing nocebo hyperalgesia. However, little is known about the psychological mechanisms by which expectations exacerbate the perception of pain. A potential mechanism that has been proposed within wider pain research is pain-related attention. The aim of the present study was thus to explore whether attention bias (AB) to pain influenced nocebo hyperalgesia. One-hundred and thirty-four healthy participants were randomized in a 2 (AB training: towards vs away from pain) × 2 (nocebo condition: nocebo vs control) design. Pain-related AB was manipulated through a novel, partially gaze-contingent dot-probe task. Participants then completed either a nocebo instruction and conditioning paradigm or a matched control condition. Primary outcomes were measures of expectancy, anticipatory anxiety, and pain intensity completed during a nocebo test phase. Results showed that the AB manipulation was unsuccessful in inducing ABs either toward or away from pain. The nocebo paradigm induced significantly greater expectancy, anticipatory anxiety, and pain intensity for the nocebo groups compared to the control groups. In a posthoc analysis of participants with correctly induced ABs, AB towards pain amplified nocebo hyperalgesia, expectancy, and anticipatory anxiety relative to AB away from pain. The results are consistent with the expectancy model of nocebo effects and additionally identify anticipatory anxiety as an additional factor. Regarding AB, research is needed to develop reliable means to change attention sample-wide to corroborate the present findings. PERSPECTIVE: This article explores the role of AB, expectancy, and anticipatory anxiety in nocebo hyperalgesia. The study shows that expectancy can trigger anticipatory anxiety that exacerbates nocebo hyperalgesia. Further, successful AB training towards pain heightens nocebo hyperalgesia. These findings identify candidate psychological factors to target in minimizing nocebo hyperalgesia., (Copyright © 2024 United States Association for the Study of Pain, Inc. Published by Elsevier Inc. All rights reserved.)