The development and measurement properties of the Dutch version of the fear-avoidance component scale (FACS-D) in persons with chronic musculoskeletal pain

Abstract

Introduction: Habituation to pain is a generally known phenomenon that involves a decrease in response after repeated painful stimulation 1. A variety of methods is available to measure short-term habituation. Nevertheless, the neural correlates are not well understood. Therefore, we developed a protocol integrating psychophysical and neural measures. Methods: Participants received three blocks of 25 brief painful electric stimuli while fMRI data was collected. After each stimulus, participants rated their pain on a visual analogue scale (VAS). The protocol was designed in a way to include ratings, allow for habituation and limit the influence of motor responses on the pain response. Analysis of habituation includes multilevel models for pain ratings and brain activity over blocks and on a trial-by-trial basis. Results: Preliminary results (n = 5) indicated a decrease in pain ratings, with large individual differences. In addition , we found brain activity in areas involved in pain processing in general (i.e., insula, cingulate cortex), which showed decreased activity over blocks of painful stimulation. Furthermore, in more refined analyses (trial-by-trial), we expect to find a linear decrease in activity in the anterior/midcingulate cortex, reflecting the decrease in subjective pain perception. Discussion: Our developed protocol allows for the investigation of short-term habituation with fMRI using self-report, block and trial-by-trial analyses and increases our understanding of individual differences in habitua-tion to pain. Process evaluation: Habituation can be measured in multiple ways, which complicates standardisation of paradigms and analyses. A protocol which allows for the integration and comparison of these methods helps to define and understand habituation. References: 1. Rankin CH, Abrams T, Barry RJ, et al. Habituation revisited: an updated and revised description of the behavioral characteristics of habituation. Neurobiology of learning and memory 2009; 92(2): 135-138. Introduction: The relevance of spine MRI data to understanding low back pain (LBP) is questioned but it remains one of the few ways to assess pathoanatomical features of the condition. A need for more reliable quantitative interpretation of clinical MRI data has arisen in step with growing interest in the genetic architecture of LBP and associated systemic and immunometablolic factors. Methods: We aim to quantitatively classify disc degen-eration (DD) imaging phenotypes using deep learning (DL). We have identified from the Northern Finland Birth Cohort target phenotypes derived from qualitative DD schemas and Modic change size. We will use DL and radiomic analysis to train models classifying these target phenotypes, externally validated on TwinsUK. We will then use the results to refine phenotype definitions. These data-driven phenotypes will be investigated in genome wide association studies (GWAS) to locate associated single nucleotide polymorphisms and immuno-metabolic pathways. Results: We expect the resultant model to accurately classify DD phenotypes, allowing coding of large cohorts for GWAS and other data-driven approaches identifying biological aspects of LBP. Discussion: For MRI to benefit LBP sufferers, quantitative approaches to interpretation are needed. DL can contribute to effective sub-grouping based on MRI that can impact both research and clinical management.

Introduction: The Fear-Avoidance Components Scale (FACS) has been developed within the framework of the most current fear-avoidance model.1 This study aimed to translate the FACS into Dutch, and to investigate its measurement properties in patients with chronic muscu-loskeletal pain. Methods: The original English FACS was translated in Dutch through forward-backward translation. The FACS-D’s measurement properties were evaluated in 224 persons with chronic musculoskeletal pain. Internal consistency, test- retest reliability and measurement error were assessed with the Cronbach’s alpha coefficient (α), intraclass correlation coefficient (ICC), standard error of measurement (SEM) and smallest detectable change (SDC). Construct validity (including structural validity and hypothesis testing) was assessed through inter-item correlation analyses, exploratory factor analysis and by examining relationships between the FACS-D and other patient- reported instruments. Results: Internal consistency and test- retest reliability were high (α = 0.92; ICC = 0.92), and the SEM was 5.6 points. Regarding structural validity, low inter-item cor-relations were found for item 12. A two-factor model was found to best fit the data: one factor covered pain- related cognitions and emotions, the second factor covered items regarding avoidance behaviour. Five out of seven of the a priori-formulated hypotheses were confirmed. Discussion: The FACS-D has good reliability and va-lidity, and can be used to evaluate fear-avoidance in persons with chronic musculoskeletal pain. It’s a two- dimensional scale that assesses two clinically relevant constructs of fear-avoidance behaviour. One factor cov-ers pain- related cognitions and emotions, while the other factor covers avoidance behaviour. Process evaluation: Notwithstanding the sound method-ology, the paper's content is considered of low priority by editors. Reference: 1. Neblett R, Mayer TG, Hartzell MM, Williams MJ, Gatchel RJ. The Fear-avoidance Components Scale (FACS): Development and Psychometric Evaluation of a New Measure of Pain- related Fear Avoidance. Pain P ra ct ic e. 2016;16(4):435 – 450.