Translation, cross-cultural adaptation, and measurement properties of the Arabic version of the fear avoidance components scale.

PURPOSE: This study aimed to translate, validate, and cross-culturally adapt the original FACS into the Arabic language. METHODS: The English version of the FACS was translated and culturally adapted into Arabic following international guidelines. The psychometric properties of the final version of the FACS-Arabic (FACS-A) were tested among 119 patients with different musculoskeletal (MSK) pain disorders. RESULTS: The Cronbach's α for the FACS-A was 0.86. The test-retest reliability, measured with intraclass correlation coefficient, was 0.80. The FACS-A showed positive significant correlations with other psychological patient-reported measures, including the pain catastrophizing scale (PCS) (r = 0.545); p ≤ 0.01), Brief Pain Inventory (BPI)-pain score (r = 0.546; p ≤ 0.01), BPI-pain interference score (r = 0.511; p ≤ 0.01), and Hospital Anxiety and Depression Scale (HADS) (r = 0.451, 0.336, respectively; p ≤ 0.01). Confirmatory factor analysis of the FACS-A confirmed the two-factor structure found in the original English version. CONCLUSION: This study determined the FACS-A to be a reliable and valid tool for the assessment of the fear-avoidance beliefs in Arabic-speaking individuals with MSK pain disorders.

The Arabic version of the fear avoidance component scale is a reliable and valid tool to assess pain fear-avoidance beliefs in individuals with musculoskeletal pain.This tool can be used to assess fear-avoidance beliefs in clinical practice for Arabic-speaking individuals.

Correction: Cross-cultural translation and psychometric validation of the French version of the Fear-Avoidance Components Scale (FACS).

[This corrects the article DOI: 10.1371/journal.pone.0288899.].

Is the Central Sensitization Inventory (CSI) associated with quantitative sensory testing (QST)? A systematic review and meta-analysis.

Central sensitization (CS) involves an amplification of neural processing within the central nervous system that can result in widespread pain patterns and hypersensitivity to stimuli. The Central Sensitization Inventory (CSI) and various quantitative sensory testing (QST) methods purport to assess clinical markers of CS. The purpose of this systematic review and meta-analysis was to summarize and quantify the associations between total CSI scores and QST measures from previous studies. A systematic search identified 39 unique studies that were deemed eligible for the systematic review and 33 studies for meta-analyses (with 3314 subjects and 154 effect sizes), including five QST modalities: conditioned pain modulation, temporal summation, pressure pain threshold, heat pain threshold, and cold pain threshold. The meta-analysis yielded statistically significant CSI-QST correlations in total subject samples for all five QST modalities. The strongest associations were identified between CSI scores and pain threshold testing, especially pressure pain threshold, in which 51% of effects sizes, from 29 studies and 3071 subjects, were determined to be in a medium to large range.

To what degree patient-reported symptoms of central sensitization, kinesiophobia, disability, sleep, and life quality associated with 24-h heart rate variability and actigraphy measurements?

OBJECTIVES: Chronic musculoskeletal pain is associated with decreased parasympathetic and increased sympathetic activity in the autonomic nervous system. The objective of this study was to determine the associations between objective measures of heart rate variability (a measure of autonomic nervous system function), actigraphy (a measure of activity and sleep quality), respiration rates, and subjective patient-reported outcome measures (PROMs) of central sensitization, kinesiophobia, disability, the effect of pain on sleep, and life quality. METHODS: Thirty-eight study subjects were divided into two subgroups, including low symptoms of central sensitization (n = 18) and high symptoms of central sensitization (n = 20), based on patient-reported scores on the Central Sensitization Inventory (CSI). Heart rate variability (HRV) and actigraphy measurements were carried out simultaneously in 24 h measurement during wakefulness and sleep. RESULTS: A decrease in HRV during the first 2 h of sleep was stronger in the low CSI subgroup compared to the high CSI subgroup. Otherwise, all other HRV and actigraphy parameters and subjective measures of central sensitization, disability, kinesiophobia, the effect of pain on sleep, and quality of life showed only little associations. DISCUSSION: The high CSI subgroup reported significantly more severe symptoms of disability, kinesiophobia, sleep, and quality of life compared to the low CSI subgroup. However, there were only small and nonsignificant trend in increased sympathetic nervous system activity and poorer sleep quality on the high central sensitization subgroup. Moreover, very little differences in respiratory rates were found between the groups.

Effectiveness of an online multicomponent program (FATIGUEWALK) for chronic fatigue syndrome: A randomized controlled trial.

OBJECTIVE: This study aimed to evaluate the effectiveness of an online multicomponent intervention called FATIGUEWALK (FaW) compared to treatment as usual (TAU) in patients with chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). METHOD: FaW included pain neuroscience education, therapeutic exercise, cognitive restructuring, and mindfulness training. A total of 428 patients with CFS/ME were randomized into two study arms: online FaW plus TAU versus TAU alone. A single-blinded randomized controlled trial was conducted. Validated patient-reported outcome measures of fatigue, pain, anxiety, depression, and physical function were collected at baseline and posttreatment, following the FaW intervention, which lasted 12 weeks. RESULTS: Statistically significant improvements (with small-to-moderate effect sizes) were observed in online FaW versus TAU alone with respect to multidimensional aspects of fatigue (Cohen's d ranging from 0.25 to 0.73) and most secondary outcomes (pain and fatigue intensity, depressive and anxious symptomatology, functional impairment, kinesiophobia, physical functioning). The absolute risk reduction in FaW versus TAU was 19%, 95% confidence interval (CI) [12.19, 25.80] with number needed to treat = 6, 95% CI [3.9, 8.2]. Overall, similar clinical improvements were observed in sensitivity analyses including a subgroup of patients without comorbidity with fibromyalgia (n = 70). CONCLUSIONS: This is the first study to assess the short-term effectiveness of an online multicomponent intervention added to TAU, compared to TAU alone, for the management of CFS/ME. Further trials, including active control groups with an equivalent treatment dose, and assessing the long-term effectiveness of the online FaW, are warranted. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Cross-cultural translation and psychometric validation of the French version of the Fear-Avoidance Components Scale (FACS).

BACKGROUND: The Fear-Avoidance Components Scale (FACS) is a reliable and valid instrument widely used to assess fear-avoidance beliefs related to pain and disability. However, there is a scarcity of validated translations of the FACS in different cultural and linguistic contexts, including the French population. This study aimed to translate and validate the French version of the FACS (FACS-Fr/CF), examining its psychometric properties among French-speaking individuals. METHODS: A cross-cultural translation process-including forward translation, backward translation, expert committee review, and pre-testing-was conducted to develop the FACS-Fr/CF. The translated version was administered to a sample of French-speaking adults (n = 55) with chronic musculoskeletal pain. Internal consistency (including confirmatory analyses of the 2 factors identified in the Serbian version), test-retest reliability and convergent validity were then assessed. RESULTS: The FACS-Fr/CF demonstrated high global internal consistency (α = 0.94, 95% CI: 0.91-0.96) as well as high internal consistency of the 2 factors identified in the Serbian version (α = 0.90, 95% CI: 0.86-0.94 and α = 0.90, 95% CI: 0.85-0.94, respectively). Test-retest analysis revealed a moderate (close to high) reliability (ICC = 0.89; 95% CI: 0.82-0.94 and r = 0.89; p<0.005). Convergent validity was supported by significant correlations between the FACS-Fr/CF scores and the Tampa Scale for Kinesiophobia (r = 0.82; p < 0.005), the Pain Catastrophizing Scale (r = 0.72; p < 0.005) and the Hospital Anxiety and Depression Scale (r = 0.66; p < 0.005). CONCLUSION: The present study provides evidence for the cross-cultural translation and psychometric validation of the FACS-Fr/CF. The FACS-Fr/CF exhibits a high internal consistency, a moderate (close to high) test-retest reliability, and good construct validity, suggesting its utility in assessing fear-avoidance beliefs in the French-speaking population. This validated tool can enhance the assessment and understanding of fear-avoidance behaviors and facilitate cross-cultural research in pain-related studies.

Patients with neuropathic pain from lumbosacral radiculopathy demonstrate similar pressure pain thresholds and conditioned pain modulation to those with fibromyalgia.

OBJECTIVE: The purpose of the study was to evaluate pain thresholds, impairment of the endogenous pain modulatory system, and self-reported cognitive-emotional and central sensitization-related symptoms among three subject groups: a rarely studied patient cohort with neuropathic pain from lumbosacral radiculopathy (NPLSR), patients with fibromyalgia (FM) and healthy controls (HC). METHODS: Patient-reported pain-related symptomology was evaluated with psychometricallyvalidated questionnaires. Pressure pain threshold (PPT), heat pain threshold (HPT), and cold pain threshold (CPT) were assessed in the low back and contralateral forearm. Conditioned pain modulation (CPM) was evaluated with a recently introduced methodology that accounts for a standard error of measurement. RESULTS: Compared to the HC subjects, the FM and NPLSR subjects had significantly lower pain thresholds and more CPM impairment. No significant differences in PPT and CPM were observed between the FM and NPLSR groups. Significant group differences were found in self-reported symptoms of depression, anxiety, stress, and central sensitization. Self-reported symptom severity increased in a stair-step fashion, with the HC group scoring lowest and FM group scoring highest. CONCLUSION: The NPLSR group manifested CPM dysfunction and pressure hyperalgesia at similar levels to the FM group, indicating that these two chronic pain syndromes, likely based on different pathophysiological mechanisms, in fact share some common pain processing features. However, though both patient groups demonstrated similarities in pain processing, self-reported cognitive-emotional and central sensitization-related symptom severity was significantly higher in the FM cohort, which distinguished them from the chronic NPLSR cohort.

Central Sensitisation Inventory-Thai version: translation, cross-cultural adaptation, and psychometric evaluation in chronic non-specific neck pain.

PURPOSE: To translate and cross-culturally adapt the English version of the Central Sensitisation Inventory (CSI) into Thai (CSI-Thai) and to evaluate its psychometric properties in individuals with chronic non-specific neck pain. MATERIALS AND METHODS: Cross-cultural translation and adaptation of the CSI were performed according to standard guidelines. A total of 340 participants were invited to complete the CSI-Thai, Visual Analogue Scale (pain intensity), Neck Disability Index, Fear-Avoidance Beliefs Questionnaire, Pain Catastrophising Scale (PCS), and Short Form-36. Psychometric evaluation included confirmatory factor analysis, internal consistency, test-retest reliability, agreement, and construct validity. RESULTS: Dimensionality analyses indicated that a bifactor model, comprising one general factor plus four orthogonal factors, fit the CSI structure better than unidimensional and the four-factor models. The general factor showed substantial reliability (Cronbach α = 0.91, Omega ω = 0.94, and omega hierarchical ω-h = 0.91). The intraclass correlation coefficient was 0.90, representing excellent stability over a 48 h interval. Moderate-to-strong correlations and acceptable-to-excellent discriminations were found between the CSI-Thai and all questionnaires. The exception was the PCS (no correlation and discrimination). The standard error of measurement and minimal detectable change of the CSI-Thai were 2.33 and 6.47, respectively. CONCLUSIONS: The translation and cross-cultural adaptation of the CSI-Thai were successful, with satisfactory reliability and construct validity.Implications for rehabilitationCentral Sensitisation Inventory-Thai version (CSI-Thai) is successfully adapted and demonstrated satisfactory reliability and construct validity.The CSI-Thai can be applicable to assess central sensitisation-related signs and symptoms in Thai-speaking patients with chronic non-specific neck pain (CNSNP) both clinical and research purposes.The CSI-Thai correlated to pain, disability and quality of life among patients with CNSNP.

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

OBJECTIVES: The Fear-Avoidance Components Scale (FACS) is a recently developed patient-reported instrument assessing different constructs related to the fear-avoidance model of pain. The aim was to translate the original English FACS into Dutch (FACS-D) and assess its measurement properties in persons with chronic musculoskeletal pain. METHODS: The original English FACS (20 item-scale, range: 0-100) was translated in Dutch through standard forward-backward translation methodology. 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), and standard error of measurement (SEM). Construct validity was assessed through inter-item correlation analyses, exploratory factor analysis, association with other fear-avoidance-related constructs, and hypothesis testing. RESULTS: Internal consistency, test-retest reliability and hypotheses testing were good (α=0.92; ICC=0.92, CI 0.80-0.96; 7/8 hypotheses confirmed). Similar to the original FACS and other translated versions, a two-factor model best fit the data. However, the item distribution differed from other versions. One factor represented "pain-related cognitions and emotions" and a second factor represented "avoidance behaviour." In contrast to the original FACS, low inter-item correlations for item 12 were found. The FACS-D was more strongly associated with fear-avoidance-related constructs of pain severity, perceived disability, feelings of injustice, and depressive/anxiety symptoms than the other fear-avoidance-related scales studied here. CONCLUSIONS: The FACS-D demonstrated good reliability and construct validity, suggesting that it may be a useful measure for Dutch-speaking healthcare providers. Two clinically relevant factors, with a different item distribution than the original FACS, were identified: one covering items on pain-related cognitions and emotions, and one covering items on avoidance behaviour. The stronger association between FACS-D and fear-avoidance related constructs suggests that the FACS-D may be more effective in evaluating the cognitive, emotional and behavioural constructs of pain-related fear-avoidance than other similar measures.

Effectiveness, cost-utility and physiological underpinnings of the FIBROWALK multicomponent therapy in online and outdoor format in individuals with fibromyalgia: Study protocol of a randomized, controlled trial (On&Out study).

Introduction: The On&Out study is aimed at assessing the effectiveness, cost-utility and physiological underpinnings of the FIBROWALK multicomponent intervention conducted in two different settings: online (FIBRO-On) or outdoors (FIBRO-Out). Both interventions have proved to be efficacious in the short-term but there is no study assessing their comparative effectiveness nor their long-term effects. For the first time, this study will also evaluate the cost-utility (6-month time-horizon) and the effects on immune-inflammatory biomarkers and Brain-Derived Neurotrophic Factor (BDNF) levels of both interventions. The objectives of this 6-month, randomized, controlled trial (RCT) are 1) to examine the effectiveness and cost-utility of adding FIBRO-On or FIBRO-Out to Treatment-As-Usual (TAU) for individuals with fibromyalgia (FM); 2) to identify pre-post differences in blood biomarker levels in the three study arms and 3) to analyze the role of process variables as mediators of 6-month follow-up clinical outcomes. Methods and analysis: Participants will be 225 individuals with FM recruited at Vall d'Hebron University Hospital (Barcelona, Spain), randomly allocated to one of the three study arms: TAU vs. TAU + FIBRO-On vs. TAU + FIBRO-Out. A comprehensive assessment to collect functional impairment, pain, fatigue, depressive and anxiety symptoms, perceived stress, central sensitization, physical function, sleep quality, perceived cognitive dysfunction, kinesiophobia, pain catastrophizing, psychological inflexibility in pain and pain knowledge will be conducted pre-intervention, at 6 weeks, post-intervention (12 weeks), and at 6-month follow-up. Changes in immune-inflammatory biomarkers [i.e., IL-6, CXCL8, IL-17A, IL-4, IL-10, and high-sensitivity C-reactive protein (hs-CRP)] and Brain-Derived Neurotrophic Factor will be evaluated in 40 participants in each treatment arm (total n = 120) at pre- and post-treatment. Quality of life and direct and indirect costs will be evaluated at baseline and at 6-month follow-up. Linear mixed-effects regression models using restricted maximum likelihood, mediational models and a full economic evaluation applying bootstrapping techniques, acceptability curves and sensitivity analyses will be computed. Ethics and dissemination: This study has been approved by the Ethics Committee of the Vall d'Hebron Institute of Research. The results will be actively disseminated through peer-reviewed journals, conference presentations, social media and various community engagement activities. Trial registration number NCT05377567 (clinicaltrials.gov).

Data-Driven Path Analytic Modeling to Understand Underlying Mechanisms in COVID-19 Survivors Suffering from Long-Term Post-COVID Pain: A Spanish Cohort Study.

Pain can be present in up to 50% of people with post-COVID-19 condition. Understanding the complexity of post-COVID pain can help with better phenotyping of this post-COVID symptom. The aim of this study is to describe the complex associations between sensory-related, psychological, and cognitive variables in previously hospitalized COVID-19 survivors with post-COVID pain, recruited from three hospitals in Madrid (Spain) by using data-driven path analytic modeling. Demographic (i.e., age, height, and weight), sensory-related (intensity or duration of pain, central sensitization-associated symptoms, and neuropathic pain features), psychological (anxiety and depressive levels, and sleep quality), and cognitive (catastrophizing and kinesiophobia) variables were collected in a sample of 149 subjects with post-COVID pain. A Bayesian network was used for structural learning, and the structural model was fitted using structural equation modeling (SEM). The SEM model fit was excellent: RMSEA < 0.001, CFI = 1.000, SRMR = 0.063, and NNFI = 1.008. The only significant predictor of post-COVID pain was the level of depressive symptoms (ß=0.241, p = 0.001). Higher levels of anxiety were associated with greater central sensitization-associated symptoms by a magnitude of ß=0.406 (p = 0.008). Males reported less severe neuropathic pain symptoms (−1.50 SD S-LANSS score, p < 0.001) than females. A higher level of depressive symptoms was associated with worse sleep quality (ß=0.406, p < 0.001), and greater levels of catastrophizing (ß=0.345, p < 0.001). This study presents a model for post-COVID pain where psychological factors were related to central sensitization-associated symptoms and sleep quality. Further, maladaptive cognitions, such as catastrophizing, were also associated with depression. Finally, females reported more neuropathic pain features than males. Our data-driven model could be leveraged in clinical trials investigating treatment approaches in COVID-19 survivors with post-COVID pain and can represent a first step for the development of a theoretical/conceptual framework for post-COVID pain.

Phenotyping Post-COVID Pain as a Nociceptive, Neuropathic, or Nociplastic Pain Condition.

Pain after an acute Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19) condition (post-COVID pain) is becoming a new healthcare emergency. Precision medicine refers to an evidence-based method of grouping patients based on their diagnostic/symptom presentation and then tailoring specific treatments accordingly. Evidence suggests that post-COVID pain can be categorized as nociceptive (i.e., pain attributable to the activation of the peripheral receptive terminals of primary afferent neurons in response to noxious chemical, mechanical, or thermal stimuli), neuropathic (i.e., pain associated with a lesion or disease of the somatosensory nervous system and limited to a "neuroanatomically plausible" distribution of the system), nociplastic (i.e., pain arising from altered nociception despite no clear evidence of actual or threatened tissue damage causing the activation of peripheral nociceptors or evidence for disease or lesion of the somatosensory system causing the pain), or mixed type (when two pain phenotypes co-exist). Each of these pain phenotypes may require a different treatment approach to maximize treatment effectiveness. Accordingly, the ability to classify post-COVID pain patients into one of these phenotypes would likely be critical for producing successful treatment outcomes. The 2021 International Association for the Study of Pain (IASP) clinical criteria and grading system provide a framework for classifying pain within a precision pain medicine approach. Here we present data supporting the possibility of grouping patients with post-COVID pain into pain phenotypes, using the 2021 IASP classification criteria, with a specific focus on nociplastic pain, which is probably the primary mechanism involved in post-COVID pain. Nociplastic pain, which is usually associated with comorbid symptomology (e.g., poor sleep quality, fatigue, cognitive-emotional disturbances, etc.) and is considered to be more difficult to treat than other pain types, may require a more nuanced multimodal treatment approach to achieve better treatment outcomes.

Effectiveness of two video-based multicomponent treatments for fibromyalgia: The added value of cognitive restructuring and mindfulness in a three-arm randomised controlled trial.

BACKGROUND/OBJECTIVES: The aim of this study was to examine the effectiveness of two video-based multicomponent programs (FIBROWALK) and the Multicomponent Physiotherapy Program (MPP) for patients with fibromyalgia (FM) compared to treatment-as-usual (TAU) only. We posit that FIBROWALK, due to inclusion of specific psychological ingredients (cognitive restructuring and mindfulness), can produce additional clinical benefits when compared to TAU or MPP alone. METHODS: A total of 330 patients with FM were recruited and randomly allocated (1:1:1) to TAU only, TAU + FIBROWALK, or TAU + MPP. FIBROWALK and MPP consisted of weekly videos on pain neuroscience education, therapeutic exercise and self-management patient education, but only the FIBROWALK intervention provided cognitive restructuring and mindfulness. Both programs were structurally equivalent. Between-group differences in functional impairment, pain, kinesiophobia, anxious-depressive symptoms and physical functioning were evaluated at post-treatment following Intention-To-Treat and complete-case approaches. RESULTS: Compared to TAU only, individuals in the FIBROWALK arm showed larger improvements in all clinical outcomes; similarly, participants in the MPP program also showed greater improvements in functional impairment, perceived pain, kinesiophobia, depressive symptoms compared to TAU only. The FIBROWALK intervention showed superior effects in improving pain, anxiety and depressive symptoms and physical functioning compared to MPP. CONCLUSIONS: This RCT supports the short-term effectiveness of the video-based multicomponent programs FIBROWALK and MPP for FM and provides evidence that cognitive-behavioural and mindfulness-based techniques can be clinically useful in the context of physiotherapeutic multicomponent treatment programs. TRIAL REGISTRATION NUMBER: NCT04571528.

Psychometric validation of the Polish version of the Central Sensitization Inventory in subjects with chronic spinal pain.

BACKGROUND: Central sensitization is an amplification of neuronal signaling within the central nervous system. The Central Sensitization Inventory was introduced in 2012. A Polish version of the CSI (CSI-Pol) was developed in 2019, but it was not psychometrically validated. The aim of this study was to validate the CSI-Pol in a sample of Polish-speaking patients with chronic spinal pain and compare them with a group of healthy control subjects. METHODS: The CSI-Pol was administered to 151 patients with chronic spinal pain recruited from two centers. It was re-administered 7 days later. The psychometric properties were then evaluated, including test-retest reliability, construct validity, factor structure and internal consistency. We correlated the CSI-Pol with functional scales, depression and social support scales and compared CSI-Pol scores in the clinical subjects with 30 healthy control subjects recruited from medical staff and their families. RESULTS: The CSI-Pol demonstrated excellent internal consistency (Cronbach's α =0,933) and test-retest reliability (Intraclass Correlation Coefficients - ICC =0.96), as well as significant positive associations with other patient-reported scales, including the Neck Disability Index (r = 0.593), Revised Oswestry Low Back Pain Disability Questionnaire (r = 0.422), and other measures of functional and depressive states. An exploratory factor analysis resulted in a 4-factor model. CSI-Pol scores in the clinical sample (35.27 ± 17.25) were significantly higher than the control sample (23.3 ± 8.9). CONCLUSION: The results of this study suggest that the CSI-Pol may be a useful clinical tool for assessing central sensitization related symptoms and guiding appropriate treatment in Polish-speaking patients with spinal pain.

Cross-cultural adaptation and validation of the German Central Sensitization Inventory (CSI-GE).

BACKGROUND: The Central Sensitization Inventory (CSI) is a screening tool designed to detect symptoms related to Central Sensitization (CS) and Central Sensitivity Syndromes (CSS) by measuring the degree of related phenomena. The objective of this study was to create a German, culturally-adapted version of the CSI and to test its psychometric properties. METHODS: A German version of the CSI (CSI-GE) was developed, culturally-adapted, and pretested for comprehensibility. The psychometric properties of the resulting version were validated in a clinical study with chronic pain and pain-free control subjects. To assess retest reliability, the CSI-GE was administered twice to a subgroup of patients. Structural validity was tested using factor analyses. To investigate construct validity a hypotheses testing approach was used, including (1) correlations between the CSI-GE and several other well-established questionnaires as well as (2) an investigation of the CSI-GE discriminative power between different subgroups of participants believed to have different degrees of CS. RESULTS: The CSI-GE showed excellent reliability, including high test-retest characteristics. Factor analyses confirmed a bi-factor dimensionality as has been determined previously. Analysing construct validity 6 out of 11 hypotheses (55%) were met. CSI-GE scores differentiated between subgroups according to expectations. Correlations between CSI-GE scores and other questionnaires suggested that none of the correlated constructs was identical, but there was overlap with other questionnaires based on symptom load. Several correlations did not fit with our current understanding of CS. CONCLUSION: The CSI-GE appears to be a reliable tool for measuring CS/CSS-related symptomatology. Whether this implies that the CSI-GE measures the degree of CS within an individual subject remains unknown. The resulting score should be interpreted cautiously until further clarification of the construct.

Assessing the Functional Status of Patients with Chronic Pain-Cross Cultural Adaptation and Psychometric Properties of the Serbian Version of the Pain Disability Questionnaire.

The Pain Disability Questionnaire (PDQ) has established itself as a leading patient-reported outcome measure for assessing both mental and physical components of pain-related disability. The current study aimed to translate the PDQ into Serbian and validate its psychometric properties. Following a standard translation process, a total of 554 chronic pain patients (average age 55.37 ± 12.72 years; 375 (67.5%) females) completed the PDQ-Serb, Oswestry Disability Index (ODI), Short Form-36 (SF-36), pain intensity rating and a six-minute walk test (6MWT). Responsiveness was examined in a subsample of 141 patients who completed an inpatient rehabilitation program. The internal consistency of the PDQ-Serb was excellent (Cronbach α = 0.92) and test-retest reliability was favorable (ICC = 0.87). Factor analyses found a bifactor model to be the best fit (CFI = 0.97: TLI = 0.96: RMSEA = 0.05; SRMR = 0.03). Statistically significant Pearson's coefficient correlations (p < 0.001) were found between the PDQ-Serb and ODI (r = 0.786), SF-36 Physical Components summary (r = -0.659), SF-36 Mental Components summary (r = -0.493), pain intensity rating (r = 0.572), and 6MWT (r = -0.571). Significant post-treatment improvements following inpatient rehabilitation were found with the PDQ-Serb (p < 0.001; effect size 0.431) and other clinical variables (p < 0.001; effect sizes from 0.367 to 0.536). The PDQ-Serb was shown to be a reliable and valid self-report instrument for the evaluation of pain-related disability.

Test-retest reliability of pressure pain threshold and heat pain threshold as test stimuli for evaluation of conditioned pain modulation.

OBJECTIVES: There is growing interest in conditioned pain modulation (CPM) protocols for evaluating the function of the descending pain-modulatory system in clinical settings. The aim of this study was to evaluate test-retest reliability of a CPM protocol with contact heat as a conditioning stimulus (CS) and two test stimuli (pressure pain threshold (PPT) and heat pain threshold (HPT)), all applied within one session. In addition, gender and age differences were evaluated. METHODS: The study included 87 healthy subjects (average age 37.95 ± 12.02 years, 57.5% females). The magnitude of the results of the CPM test was calculated as the difference between subject-reported pain thresholds before and after application of the CS. To assess the reliability of the protocol, a subgroup of 66 subjects underwent re-test after 14±1 days. In order to investigate the influence of age on the CPM magnitude, subjects were divided into subgroups (20-29, 30-39, 40-49, 50-59 years). RESULTS: The pain thresholds for both test stimuli (TS) were significantly higher following the application of the CS (p < 0.001). Values of the interclass correlation coefficient (ICC) for the CPM with PPT as the TS indicated good reliability (ICC=0.631, 95% CI:0.365-0.782), while those for the HPT indicated poor reliability (ICC=0.328, 95% CI:-0.067-0.582). Significant differences in CPM between genders were found for both TS. Significant CPM differences were not detected among the four age subgroups for either TS. CONCLUSIONS: CPM effects can be successfully induced with both PPT and HPT as a TS, but PPT showed significantly higher reliability.

Cross-cultural adaptation and validation of the Finnish version of the central sensitization inventory and its relationship with dizziness and postural control.

BACKGROUND: Central Sensitization (CS) involves dysfunction in neurophysiological mechanisms that increase neuronal responses to both noxious and non-noxious stimuli in the central nervous system. The Central Sensitization Inventory (CSI) is considered the leading patient-reported outcome measure for assessing CS-related symptoms. The aim of this study was to translate and cross-culturally adapt the CSI into Finnish (CSI-FI) and to evaluate its psychometric properties. METHODS: Translation and cross-cultural validation of the CSI was conducted according to established guidelines. The validation sample was 229 subjects, including 42 pain free controls and 187 subjects with chronic musculoskeletal pain. The CSI-FI was evaluated for internal consistency, test-retest reliability, exploratory factor analysis with maximum likelihood extraction, relationship with subject-reported outcome measures [Tampa scale of kinesiophobia (TSK), the Depression scale (DEPS), 5-level EQ-5D version (EQ-5 L-5D), Roland-Morris Disability Questionnaire (RMDQ), and Pain and Sleep Questionnaire Three-Item Index (PSQ-3)], pain history, subjective symptoms of dizziness, and CS-related diagnoses on CSI part B. Furthermore, we studied the ability of the CSI-FI to distinguish pain free controls, subjects with chronic pain in a single body area, and subjects with multisite chronic pain. In addition, we studied the relationship of CSI-FI scores with postural control on a force plate. RESULTS: The CSI-FI demonstrated good internal consistency (0.884) and excellent test-retest reliability (0.933) with a 7 ± 1 day gap between test administrations. Exploratory factor analysis with maximum likelihood extraction yielded a one factor solution. Fair to good correlations were found between the CSI-FI and the TSK, DEPS, EQ-5 L-5D, RMDQ, and PSQ-3. Subjective symptoms of dizziness correlated better with CSI-FI scores than any of the CS-related diagnoses on CSI part B. Total CSI-FI scores successfully distinguished between pain free controls, subjects with chronic pain in a single body area, and subjects with multisite chronic pain. The multisite pain group reported significantly more dizziness symptoms than the other two groups. Force plate measurements showed no relationship between postural control and CSI-FI scores. CONCLUSION: The CSI-FI translation was successfully cross-culturally adapted and validated into Finnish. CSI-FI psychometric properties and scores were all in acceptable levels and in line with previous CSI validations. The CSI-FI appears to be a valid and reliable instrument for assessing CS-related symptomology in Finnish-speaking populations.

Cross-cultural adaptation and psychometric validation of the Persian version of the central sensitization inventory.

BACKGROUND: The Central Sensitization Inventory (CSI) is a patient-reported tool to assess symptoms associated with central sensitization (CS). It consists of two parts: Part A assesses 25 somatic and emotional CS-related health symptoms, and part B asks if one has previously been diagnosed with a list of 10 Central Sensitivity Syndromes and related conditions. OBJECTIVES: The aim of this study was to translate and cross-culturally adapt the CSI into Persian and to evaluate its psychometric properties. DESIGN: Cross-sectional study. METHOD: After completing the Persian translation, the psychometric properties of the Persian CSI (CSI-Per) were evaluated in 256 patients with chronic pain and 46 healthy subjects. RESULTS: A confirmatory factor analysis confirmed a 1-factor model suggested in a large recent comprehensive multicountry study. Test-retest reliability (ICC = 0.934; P < 0.001) and the internal consistency (Cronbach's α = 0.87) were both good. After dividing the patient subjects into severity level subgroups, based on CSI-Per total scores, significant associations were found with the Persian version of the pain catastrophizing scale, pain duration, current pain intensity, maximum, minimum and average pain intensity in the past week and average pain intensity in the past month. In addition, total CSI-Per scores differentiated between patients and healthy subjects. CONCLUSION: The CSI-Per demonstrated good validity and reliability to assess symptoms associated with CS in Persian-speaking patients with chronic pain.