Validity of the pain anxiety symptoms scale (PASS): prediction of physical capacity variables

Pain-Related Anxiety in Spanish-Speaking Mexican Americans Who Report Chronic Pain: Psychometric Evaluation of a New Spanish Adaptation of the 20-Item Pain Anxiety Symptom Scale (PASS-20)

The 20-item Pain Anxiety Symptom Scale (PASS-20) was adapted for Spanish-speaking Mexican Americans who report chronic pain (SSMACP). The instrument measures pain-related anxiety with fear, physiological, avoidance/escape, and cognitive anxiety as subtypes. In SSMACP, the Spanish PASS-20's psychometric properties were evaluated while exploring relationships between pain-related anxiety with other variables. Using convenience sampling, 188 SSMACP (women = 108, men = 77; mean age = 37.20 years, standard deviation = 9.87) were recruited across the United States. Confirmatory factor analyses examined the structural validity of the hierarchical factor structure. Hierarchical multiple regression examined incremental validity. Correlational analyses examined convergent validity. Cronbach's coefficient alphas and McDonald's omegas examined internal consistency. Pearson's r, t-tests, and analysis of variance tests examined relationships between demographic variables and PASS-20 scores. Confirmatory factor analyses supported the hierarchical factor structure (root mean square error of approximation = .061, standardized root mean residual = .038, comparative fit index = .940). Total and subscale PASS-20 scores had acceptable convergent validity and internal consistency (range = .75-.93). Hierarchical multiple regression found that total and subscale PASS-20 scores have adequate incremental validity, considering that they contributed uniquely to the prediction of generalized anxiety scores above and beyond other pain-related scores. Demographic variables were significantly related to total and subscale PASS-20 scores. Evidence supports the use of Spanish total and subscale PASS-20 scores in SSMACP. Exploratory evidence also informed on the possible consequences and predictors of their pain-related anxiety. The results also encourage pain research in specific populations from Latin America (eg, Mexican Americans). PERSPECTIVE: The Spanish PASS-20 has adequate psychometric properties in SSMACP. This instrument can help catalyze pain research in SSMACP by informing on their pain-related anxiety and by helping evaluate other pain-related instruments. Evidence also informed on pain-related anxiety in SSMACP.

Efectividad de la Realidad Virtual (RV) en la disminución del distrés de niños y adolescentes con cáncer: Revisión sistemática

Introducción: Aunque se han publicado muchos estudios que han intentado demostrar la eficacia de diferentes tratamientos psicológicos en pacientes con cáncer; hasta la fecha no se ha revisado la evidencia disponible sobre la eficacia de la Realidad Virtual (RV) para disminuir el distrés en niños y adolescentes con cáncer. Objetivo: El objetivo principal es evaluar la efectividad de la intervención con Realidad virtual en la disminución del distrés que padecen los niños y adolescentes con cáncer ante los procedimientos médicos, la hospitalización, o la propia enfermedad. Resultados: De los 22 artículos encontrados, se han seleccionado para la revisión un total de 8, que seguían un diseño experimental o cuasiexperimental en pacientes niños y jóvenes diagnosticados de cáncer tratados con RV. Conclusiones: Los resultados, aunque heterogéneos, sugieren mejorías a medio–largo plazo en las variables de ansiedad, depresión, aceptación, calidad de vida, distrés y flexibilidad psicológica. Además, la RV ha resultado ser más eficaz que otras técnicas. De este modo, a pesar de las limitaciones encontradas en este estudio, se han obtenido resultados prometedores para futuras revisiones y/ o metaanálisis.

Effects of acute pain and pain-related fear on risky decision-making and effort during cognitive tests

Introduction: The experience of acute pain and pain-related fear negatively impact cognition and behavior; however, little research has examined their impacts on risky decision-making and effort. The present study investigated the effects of acute pain and pain-related fear on risky decision-making and effort during cognitive tests. Method: Levels of pain-related fear were assessed. Healthy participants (n = 146) experienced acute pain induced via cold pressor task, and then were randomly assigned to one of the four conditions to induce pain-related fear: Pain Threat (n = 36), Pain Threat with Control (n = 39), Cognitive Threat with Control (n = 34), and Control (n = 36). Participants then completed measures of effort (Word Memory Test [WMT], self-reported effort) and risky decision-making (Iowa Gambling Task [IGT], Balloon Analogue Risk Task [BART]). Results: Collapsed across condition, participants did not learn to decide advantageously on the IGT following an acute pain experience. During the early trials (1-40) on the IGT, participants in the Pain Threat condition made riskier decisions. Higher levels of pain during the cold pressor task predicted less risky decisions on the BART, and participants in the Cognitive Threat with Control condition made less risky decisions. Participants in the Pain Threat with Control condition self-reported lower effort on cognitive tests, yet no group-based differences were seen in WMT performance. Greater pain-related fear predicted greater self-reported effort and better WMT performance, but no effects were seen on decision-making task performance. Conclusions: The experience of pain and the threat of additional pain can lead to changes in risky decision-making and effort on cognitive tasks. This threat of additional pain could activate underlying pain-related fear, creating hypervigilance to and avoidance of pain that affects subsequent task performance. Implications for research and clinical evaluation of acute pain and pain-related fear are discussed.

Psychometric validation of the Serbian version of the Fear Avoidance Component Scale (FACS)

OBJECTIVE

The Fear Avoidance Components Scale (FACS) is a new patient-reported outcome (PRO) questionnaire designed to comprehensively evaluate fear avoidance (FA) beliefs and attitudes in persons with painful medical conditions. The original English version has demonstrated acceptable psychometric properties, including concurrent and predictive validity. Two factors have been identified: 1. general fear avoidance; and 2. types of activities that are avoided.

METHODS

The FACS was first translated into Serbian, and then psychometrically validated. A cohort of 322 chronic musculoskeletal pain subjects completed the FACS-Serb and additional FA-related patient-reported outcome (PRO) measures. Their FACS-Serb scores were then compared to a cohort of 68 acute pain subjects.

RESULTS

Test-retest reliability (ICC2,1 = 0.928) and internal consistency for both Factors (Cronbach α 0.904 and 0,880 respectively) were very good. An acceptable fit was found with a confirmatory factor analysis of the 2-factor model found with the original English version of the FACS. Strong associations were found among FACS-Serb scores and other PRO measures of pain catastrophizing, depressive/anxiety symptoms, perceived disability, and pain intensity (p<0.001 for all analyses). FACS-Serb total scores, separate Factor scores, and subjective pain ratings were significantly higher in the chronic vs. acute pain cohorts (p<0.001 for all analyses).

CONCLUSIONS

The FACS-Serb demonstrated strong psychometric properties, including strong reliability and internal consistency, criterion validity (through associations with other FA-related PRO measures), and discriminant validity (through comparisons with a separate acute pain cohort). The FACS-Serb appears to be a potentially useful pain-related assessment tool.

Predictors of acute care utilization and acute pain treatment outcomes in adults with sickle cell disease: The role of non-hematologic characteristics and baseline chronic opioid dose

Despite its rarity in the United States, sickle cell disease accounts for a disproportionate amount of healthcare utilization and costs. The majority of this is due to acute care for painful crises. A small subpopulation of patients accounts for most these costs due to frequent visits to emergency departments and acute care facilities. Previous investigations have found that these high utilizing patients are distinguished by both a more severe disease course and certain non-hematologic characteristics, which may include higher socioeconomic status and some psychiatric and psychological characteristics. This prospective observational cohort study was undertaken to test the ability of these characteristics to prospectively predict acute pain care outcomes, including visit frequency, total opioid doses, and pain improvement at the Johns Hopkins Sickle Cell Infusion Center (SCIC). Seventy-three participants were followed for 12 months and SCIC utilization and treatment outcomes were tabulated for 378 visits. Participants who visited the SCIC most frequently had markedly worse pain improvement despite higher within-visit opioid doses. Higher utilization was associated with indicators of greater illness severity, more aggressive treatment for sickle cell disease, higher baseline opioid doses, higher socioeconomic status, greater pain-related anxiety, and a history of psychiatric treatment. Overall, poor acute pain treatment response was associated with higher utilization and higher baseline opioid doses. The pattern of association between high utilization, poor acute care outcomes, and higher baseline opioid doses is discussed in terms of prior research and future directions.

Goal conflict in chronic pain: day reconstruction method

Background

When suffering from chronic pain, attempts to control or avoid pain often compete with other daily activities. Engaging in one activity excludes engaging in another, equally valued activity, which is referred to as "goal conflict." As yet, the presence and effects of goal conflicts in patients with chronic pain remain poorly understood.

Methods

This study systematically mapped the presence and experience of goal conflicts in patients with fibromyalgia compared to healthy controls. A total of 40 patients and 37 controls completed a semi-structured interview in which they first reconstructed the previous day, identified conflicts experienced during that day, and classified each of the conflicting goals in one of nine goal categories. Additionally, they assessed how they experienced the previous day and the reported conflicts.

Results

Results showed that patients did not experience more goal conflicts than healthy controls, but that they did differ in the type of conflicts experienced. Compared to controls, patients reported more conflicts related to pain, and fewer conflicts involving work-related, social or pleasure-related goals. Moreover, patients experienced conflicts as more aversive and more difficult to resolve than control participants.

Discussion

This study provides more insight in the dynamics of goal conflict in daily life, and indicates that patients experience conflict as more aversive than controls, and that conflict between pain control (and avoidance) and other valued activities is part of the life of patients.

Validations and psychological properties of a simplified Chinese version of pain anxiety symptoms scale (SC-PASS)

The Pain Anxiety Symptoms Scale (PASS) has been developed to evaluate pain anxiety, which leads to avoidance of daily activities and normal movements. However, a simplified Chinese version of PASS is still not available. Physicians are not aware of which patients are prone to anxiety, and what the risk factors are.To cross-culturally adapt the PASS into a simplified Chinese version and test the reliability and validity. Factors affecting pain anxiety were also explored.The PASS was first translated into a simplified Chinese version according to a forward-backward method. Then, validations were tested including content validity, construct validity, and reliability. Content validity was analyzed by response trend. Construct validity was analyzed by confirmatory factor analysis (CFA), exploratory factor analysis, and priori hypotheses testing. Reliability was analyzed by internal consistency and test-retest reliability. Risk factors of catastrophizing were analyzed by performing multivariate liner regression.A total of 219 patients were included in the study. The scores of items were well distributed. Both CFA and exploratory factor analysis suggested a 2nd-order, 4-factor model, accounting for 65.42% of the total variance according to principle component analysis. SC-PASS obtained good reliability with a Cronbach α = 0.92 and ICC = 0.90. College education, long pain duration, and both married and divorced status were risk factors. Factors reduced pain-related anxiety were no medication assumption, female sex, widowed status, non-Han ethnicity, and having no religious belief.The SC-PASS was applicable in Chinese patients and it was suitable for the clinical uses in mainland China.

The German PASS-20 in patients with low back pain: new aspects of convergent, divergent, and criterion-related validity

BACKGROUND

The PASS-20 (McCracken and Dhingra, Pain Res Manag 7:45-50, 2002) is a shortened version of the Pain Anxiety Symptoms Scale (PASS), a self-report measure of pain anxiety. The PASS-20 demonstrates good psychometric characteristics but has not yet been validated in a German population.

PURPOSE

The aims of the present study were to (1) examine the factor structure and psychometric characteristics of the German PASS-20; (2) investigate its construct validity with respect to depression, fear-avoidance, and endurance; and (3) determine its criterion-related validity with a special emphasis on pain, disability, and quality of life.

METHOD

A principal component analysis was performed on a sample (N = 195) of patients with acute, subacute, and chronic low back pain. Reliability was examined with Cronbach's α. Validity was assessed by correlating the PASS-20 to measures of depression, anxiety, disability, quality of life, and avoidance-endurance-related behavioral pain responses.

RESULTS

The original four-factor structure proposed for the PASS-20 was replicated using the original subscale labels. The reliability of the total score and the subscales was satisfactory to excellent, and both convergent and divergent validity were moderate to high in the expected directions, showing positive correlations with anxiety, fear, depression, and fear-avoidance and negative correlations with endurance and quality of life. The PASS-20 showed unique predictive ability and advantages over the Tampa Scale of Kinesiophobia.

CONCLUSIONS

The results for the German PASS-20 support the original factor structure and provide evidence of satisfactory psychometric characteristics and usefulness in patients with low back pain.

The fear-avoidance model of chronic pain: assessing the role of neuroticism and negative affect in pain catastrophizing using structural equation modeling

BACKGROUND

Previous research on the fear-avoidance model (FAM) of chronic pain suggests that the personality traits of neuroticism and negative affect (NA) influence pain catastrophizing. However, the mechanisms of their influence on pain catastrophizing remain unclear.

PURPOSE

This study examined four possible models of relationships between neuroticism, NA, and pain catastrophizing within the FAM framework using structural equation modeling.

METHOD

A total of 401 patients with chronic musculoskeletal pain completed measures of neuroticism, NA, three core FAM components (pain catastrophizing, pain-related fear, and pain anxiety), and adjustment outcomes (pain-related disability and depression).

RESULTS

Regression analyses refuted the possibility that neuroticism and NA moderated each other's effect on pain catastrophic thoughts (p > 0.05). Results of structural equation modeling (SEM) evidenced superior data-model fit for the collapsed models in which neuroticism and NA were two secondary traits underlying a latent construct, negative emotion (disability: comparative fit index (CFI) = 0.93; depression: CFI = 0.91).

CONCLUSION

The results offer preliminary evidence that patients presenting with more neurotic symptom and heightened NA probably elicit more catastrophic thoughts about pain.

A Pilot Study of the Correlation between the Numeric Rating Scale used to Evaluate "Geop" and Questionnaires on Pain Perception

Background

The word "geop" is a unique Korean term commonly used to describe fright, fear and anxiety, and similar concepts. The purpose of this pilot study is to examine the correlation between the Numeric Rating Scale (NRS) score of geop and three different questionnaires on pain perception.

Methods

Patients aged 20 to 70 years who visited our outpatient pain clinics were evaluated. They were requested to rate the NRS score (range: 0-100) if they felt geop. Next, they completed questionnaires on pain perception, in this case the Korean version of the Pain Sensitivity Questionnaire (PSQ), the Pain Catastrophizing Scale (PCS), and the Pain Anxiety Symptoms Scale (PASS). The correlations among each variable were evaluated by statistical analyses.

Results

There was no statistically significant correlation between the NRS score of geop and the PSQ score (r = 0.075, P = 0.5605). The NRS score of geop showed a significant correlation with the PCS total score (r = 0.346, P = 0.0063). Among the sub-scales, Rumination (r = 0.338, P = 0.0077) and Magnification (r = 0.343, P = 0.0069) were correlated with the NRS score of geop. In addition, the NRS score of geop showed a significant correlation with the PASS total score (r = 0.475, P = 0.0001). The cognitive (r = 0.473, P = 0.0002) and fear factors (r = 0.349, P = 0.0063) also showed significant correlations with the NRS score of geop.

Conclusions

This study marks the first attempt to introduce the concept of "geop." The NRS score of geop showed a moderate positive correlation with the total PCS and PASS score. However, further investigations are required before the "geop" concept can be used practically in clinical fields.

Fear of injury predicts self-reported and behavioral impairment in patients with chronic low back pain

Fear of injury has been posited as crucial in pain-related anxiety and in the development of chronic pain; however, research has only measured fear of injury indirectly through other constructs (eg, fear of illness and fear of movement). The current study tested fear of injury as an independent contributor to pain-related anxiety and impairment. Patients (n = 78; 37% women) in a work-hardening treatment program for chronic low back pain completed self-report measures of pain-related anxiety, anxiety sensitivity, fear of injury, current pain, and impairment. Behavioral measures of impairment included lifting capacity, treatment outcomes, and days absent from treatment. Structural equation modeling tested the role of fear of injury within contemporary theory. Fit for the theoretical model was excellent and superior to an alternative model. Variance accounted for in pain-related anxiety by fear of injury, anxiety sensitivity, and current pain was 64%, while pain-related anxiety and current pain predicted 49% of variance in latent impairment. Fear of injury directly predicted pain-related anxiety (β = .42) and indirectly predicted impairment through pain-related anxiety (β = .19). Fear of injury may warrant theoretical and clinical consideration as an important contributor to pain-related anxiety and impairment; however, research is needed to explore how it may be causally related with other constructs.

PERSPECTIVE

Fear of injury directly predicts pain-related anxiety and indirectly predicts self-reported and behavioral impairment. Fear of injury may warrant inclusion in contemporary theories of chronic pain. Clinicians may benefit from considering the construct in interventions for chronic pain.

Factor structure and psychometric properties of the Chinese version of the 20-item Pain Anxiety Symptoms Scale (ChPASS-20)

CONTEXT

The Pain Anxiety Symptoms Scale (PASS) was designed to assess pain-related anxiety and fear. Although the scale is a reliable measure with good psychometric properties, its validity among ethnic Chinese has yet to be evaluated.

OBJECTIVES

This study aimed to translate the English-language version of the 20-item PASS into Chinese (ChPASS-20) and evaluate its factor structure, reliability, and validity.

METHODS

A total of 223 Chinese patients with chronic musculoskeletal pain attending orthopedic specialist clinics completed the ChPASS-20, the Chronic Pain Grade questionnaire, the Chinese version of the 11-item Tampa Scale of Kinesiophobia, the Hospital Anxiety and Depression Scale, and questions assessing sociodemographic and pain characteristics.

RESULTS

Confirmatory factor analyses showed that all the five-factor solutions tested met the minimum acceptable fit criterion. The four ChPASS-20 subscales and the entire scale demonstrated good internal consistency (Cronbach's αs: 0.72-0.92). All ChPASS-20 scales showed significant positive correlations with depression, pain intensity, and disability. Hierarchical multiple regression analyses showed that the ChPASS-20 total score predicted concurrent depression [F(4,159)=11.97, P<0.001], pain intensity [F(4,161)=2.47, P<0.05], and pain disability [F(4,191)=5.47, P<0.001] scores, and the ChPASS-20 Avoidance subscale (standardized beta coefficient=0.21, P<0.05) emerged as a significant independent predictor of concurrent pain disability.

CONCLUSION

Our data support the factorial validity, reliability, and construct validity of the ChPASS-20 in a Chinese population.

Predicting work status following interdisciplinary treatment for chronic pain

The effectiveness of interdisciplinary treatments for chronic pain is well established. In general, these treatments decrease psychosocial distress and increase physical abilities. Further, return to work rates following interdisciplinary treatment tend to be quite high. Previous studies have highlighted a number of factors that individually influence return to work rates; however, there is a need for more comprehensive and unified models that allow an evaluation of the inter-relations among these factors. The present investigation examined how demographic and treatment outcome variables interacted to influence post-treatment return to work rates in a sample of individuals with chronic pain following interdisciplinary treatment. Results indicated that patient age, lifting ability, pain duration, depression level, and reported disability were individually related to return to work; however, when these variables were evaluated relative to one another, level of depression and patient age had the best ability to predict post-treatment work status. These results add to the literature by specifically highlighting post-treatment factors that best discriminate patients who had returned to work from those that had not. Furthermore, they provide evidence that general emotional distress is perhaps the most important predictor of work status following treatment.

Measures of anxiety: is there a difference in their ability to predict functioning at three-month follow-up among pain patients?

Independent investigators have found that pain is related to health anxiety, trait anxiety, pain-related anxiety, and anxiety sensitivity. To date, the relationship among these anxiety-related constructs has not been studied directly and little is known about their relative ability to predict adjustment to pain over time. This paper presents longitudinal data from measures given to 227 musculoskeletal pain patients. Patients were asked at the time of their first visit (T1) to a physiotherapy clinic to complete a questionnaire package including measures of these different forms of anxiety as well as pain severity, disability, negative affect, and perceived control. Approximately 3 months later (T2), 50% of patients responded to these same questionnaires. Results showed that correlations among the anxiety measures at T1 ranged from 0.35 to 0.56. Using multiple regression analyses, measures of T1 anxiety were each examined for their ability to predict unique variance in disability, negative affect, and perceptions of control measured at T1 and T2. At T1, after controlling for pain severity and other measures of anxiety, pain-related anxiety uniquely predicted both disability and negative affect, trait anxiety uniquely predicted negative affect and perceptions of control, and anxiety sensitivity uniquely predicted negative affect. At T2, after controlling for pain severity, other measures of anxiety and each respective measure of functioning at T1, health anxiety uniquely predicted disability and negative affect, although anxiety sensitivity also uniquely contributed to the prediction of negative affect. It is concluded that the importance of various forms of anxiety is dependent on the timeframe and outcome examined. Clinical implications of the findings as well as directions for future research are discussed.

Pain-related fear: a critical review of the related measures

Objectives: In regards to pain-related fear, this study aimed to: (1) identify existing measures and review their measurement properties, and (2) identify the optimum measure for specific constructs of fear-avoidance, pain-related fear, fear of movement, and kinesiophobia. Design: Systematic literature search for instruments designed to measure fear of pain in patients with persistent musculoskeletal pain. Psychometric properties were evaluated by adjusted Wind criteria. Results: Five questionnaires (Fear-Avoidance Beliefs Questionnaire (FABQ), Fear-Avoidance of Pain Scale (FAPS), Fear of Pain Questionnaire (FPQ), Pain and Anxiety Symptoms Scale (PASS), and the Tampa Scale for Kinesiophobia (TSK)) were included in the review. The main findings were that for most questionnaires, there was no underlying conceptual model to support the questionnaire's construct. Psychometric properties were evaluated by diverse methods, which complicated comparisons of different versions of the same questionnaires. Construct validity and responsiveness was generally not supported and/or untested. Conclusion: The weak construct validity implies that no measure can currently identify who is fearful. The lack of evidence for responsiveness restricts the current use of the instruments to identify clinically relevant change from treatment. Finally, more theoretically driven research is needed to support the construct and thus the measurement of pain-related fear.

The Pain Anxiety Symptoms Scale fails to discriminate pain or anxiety in a chronic disabling occupational musculoskeletal disorder population

BACKGROUND

The Pain Anxiety Symptoms Scale (PASS) was developed to measure fear and anxiety responses to pain. Many studies have found associations between PASS scores and self-report measures of pain, anxiety, and disability as well as among inhibited movement patterns and activity avoidance behaviors (eg, kinesophobia). This study aimed to identify clinically meaningful cut-off points to identify high or low levels of pain anxiety and to determine if the PASS provides additional useful information in a functional restoration (FR) treatment program for chronic disabling occupational musculoskeletal disorder (CDOMD) patients.

METHODS

A consecutive cohort of 551 patients with CDOMD, who entered and completed a FR program, was administered a battery of psychosocial assessments, including the PASS, at admission and discharge. Socioeconomic outcomes were collected 1 year after discharge. After identifying clinical ranges for mild, moderate, and severe pain anxiety, the three groups were compared on self-report measures of psychosocial distress, clinical diagnoses of psychosocial disorders, and 1-year socioeconomic outcomes.

RESULTS

Correlations between the PASS and all measures of pain, anxiety, and disability were statistically significant. However, only the Pain Disability Questionnaire showed a large correlation coefficient (r > 0.5). Patients with the highest PASS scores were more likely to be diagnosed with a number of Axis I (depression, opioid dependence) or Axis II (Borderline Personality) psychiatric disorders. They were more likely to display treatment-seeking behavior at 1 year after discharge. However, the PASS failed to differentiate between any other 1-year outcomes.

CONCLUSIONS

The PASS is elevated when other measures of psychosocial distress are also elevated. However, the PASS fails to discriminate between different indices of depression and anxiety and it is not highly related to 1-year outcomes in a CDOMD cohort. If time and resources are limited, a different measure of psychosocial distress that does relate to socioeconomic outcomes might be a better option in a CDOMD evaluation process.

Psychometric properties of a Korean version of the Pain Anxiety Symptoms Scale-20 in chronic pain patients

BACKGROUND

The Pain Anxiety Symptoms Scale (PASS-20) consists of 20 items designed to assess four aspects of pain-related anxiety: cognitive anxiety, escape-avoidance behaviors, fear of pain, and physiological symptoms of anxiety. Although the PASS-20 is a well-established measure of pain-related anxiety in Western samples, different cultures may yield a different factor structure or different associations with pain-related outcome variables.

PURPOSE

The purposes of this study were (1) to examine the factor structure of a Korean language version of the PASS-20 (KPASS-20); (2) to examine reliability and construct validity of the KPASS-20; and (3) to compare the findings of this study with those of the original psychometric study using a Western sample.

METHOD

A total of 166 patients seeking treatment in a university pain management center located in Seoul, Korea participated.

RESULTS

Results indicated that the KPASS-20 consists of three factors, "fearful thinking," "physiological response," and "avoidance," and has adequate reliability and construct validity estimates. On the mean total score of the KPASS-20, the Korean sample had a significantly higher score than the original Western sample. In addition, in correlation analyses between the total score of the KPASS-20, physical functioning, and pain severity, the Korean sample had significantly higher coefficients, whereas similar differences were not found in the analyses of psychological functioning and depression.

CONCLUSION

The findings provide preliminary support for the reliability and validity of the KPASS-20.

Fear in arthroplasty surgery: the role of race

Understanding the difference in perceived functional outcomes between whites and blacks and the influence of anxiety and pain on functional outcomes after joint arthroplasty may help surgeons develop ways to eliminate the racial and ethnic disparities in outcome. We determined the difference in functional outcomes between whites and blacks and assessed the influence of fear and anxiety in total joint arthroplasty outcomes in 331 patients undergoing primary hip and knee arthroplasty. WOMAC, Quality of Well Being, SF-36, and Pain and Anxiety Symptoms Scale (PASS) were administered pre- and postoperatively (average 5-year followup). For the SF-36 General Health Score, blacks reported having worse perceived general health than whites before surgery. Regardless of time, blacks scored worse than whites for all measures except for the SF-36 physical function and general health scores. Blacks had a greater fear score (ie, that associated with the procedure) and total PASS score. For both races, there was a low association between the fear dimensions and dependent measures before and after surgery. Black patients undergoing hip and knee arthroplasty had lower scores than whites in most outcome measures regardless of time of assessment. We found higher fear levels before joint arthroplasty in blacks compared with whites. After surgery, blacks had much higher associations of the fear subscale, cognitive subscale, and total PASS score with the WOMAC physical function, pain, and total scores.

LEVEL OF EVIDENCE

Level II, prospective controlled cohort study. See Guidelines for Authors for a complete description of levels of evidence.

Effects of fear of movement on spine velocity and acceleration after recovery from low back pain

STUDY DESIGN

A cross-sectional assessment of the association between pain-related fear and joint motions and their higher order derivatives in 88 participants recently recovered from an episode of low back pain.

OBJECTIVE

To determine how the psychological construct of pain-related fear maps to motor behavior in standardized reaching tasks.

SUMMARY OF BACKGROUND DATA

Pain-related fear is a significant predictor of avoidance behavior and occupational disability in individuals with low back pain. However, it is not currently known how pain-related fear maps to motor behavior.

METHODS

Participants were tested at 4 weeks (+/-2 weeks) after resolution of a recent episode of back pain. Participants performed reaching tasks at comfortable and fast-paced movement speeds to 3 targets (high, middle, low) located in a midsagittal plane. Three-dimensional joint motions of the thoracic spine, lumbar spine, and hip were recorded using an electromagnetic tracking device. Group differences in joint excursions, peak velocities, and accelerations were assessed using 2-group (high pain-related fear, low pain-related fear) x 2-hand (left, right) x 2-movement speed (comfortable-pace, fast-pace) x 3-target height (high, middle, low) multivariate analyses of variances.

RESULTS

Individuals with high pain-related fear had smaller peak velocities and accelerations of the lumbar spine and hip joints for the fast-pace reaching trials.

CONCLUSION

The present study provides important evidence that pain-related fear is a robust construct that clearly maps on to differences in peak velocity and acceleration of the lumbar spine even after resolution of back pain.

An Exploration of the Psychometric Properties of the PASS-20 With a Nonclinical Sample

The Pain Anxiety Symptoms Scale-20 (PASS-20) assesses 4 factorially distinct components of pain-related anxiety (ie, cognitive, fear, escape/avoidance, physiological). The PASS-20 has good factor stability, reliability, and internal consistency in clinical samples. Psychometric data for nonclinical populations are not yet established. This study had 4 purposes: (1) To assess the factor structure of the PASS-20 with a nonclinical sample; (2) to assess concurrent validity of PASS-20 subscales with related self-report instruments; (3) to compare our results with findings of a similar study using a clinical pain sample; and (4) to suggest a preliminary cut-off score to identify individuals with significantly elevated pain-related anxiety. A sample of 155 undergraduates completed the PASS-20 as part of a larger study. Confirmatory factor analysis supported the existing 4-factor model, and internal consistencies for total and subscale scores were comparable with previous research. PASS-20 total and subscale scores were moderately correlated with other related measures, providing evidence of concurrent validity. On all PASS-20 subscales the nonclinical sample had significantly lower (P < .01) scores than those for a clinical pain sample. The majority of individuals classified as having high pain-related anxiety had PASS-20 total scores greater than 30. Implications and future research directions are discussed.

PERSPECTIVE

A nonclinical sample is used to explore the psychometric properties of the PASS-20. Confirmatory factor analysis, comparisons with a clinical pain sample, and preliminary cut-off scores indicative of high levels of pain-related anxiety are discussed. Pain-related anxiety is identified as a continuous construct, robust across both clinical and nonclinical samples.

The relationship between pain-related fear and lumbar flexion during natural recovery from low back pain

Pain-related fear has been associated with avoidance behavior and increased risk for chronic low back pain; however, few studies have examined how pain-related fear relates specifically to motion of the spine following an acute episode of back pain. Thirty-six participants with a recent episode of low back pain were recruited from the general population using a combination of fliers and radio advertisements. To explore the natural recovery from low back pain we recruited individuals who were not seeking medical care. Participants performed a forward bending task at 3, 6, and 12 weeks following onset of low back pain. Three-dimensional joint motions of the spine and hip were recorded using an electromagnetic tracking device. Initial assessments of low back pain and pain-related fear were then correlated with joint excursions observed during each forward bending. Lumbar motion was inversely related to pain-related fear, but not low back pain, at all three testing sessions. In contrast, hip motion was inversely related to pain at all three testing sessions but was not related to fear. These findings suggest that pain-related fear results in avoidance behavior that specifically limits or restricts motion of the lumbar spine.

Pain-related fear is associated with avoidance of spinal motion during recovery from low back pain

STUDY DESIGN

A longitudinal assessment of the association between pain-related fear and joint motions in 36 participants with subacute low back pain.

OBJECTIVES

To determine how the psychologic construct of pain-related fear maps to motor behavior in standardized reaching tasks.

SUMMARY OF BACKGROUND DATA

Pain-related fear is a significant predictor of avoidance behavior and occupational disability in individuals with low back pain. However, it is not currently known how pain-related fear maps to motor behavior.

METHODS

Participants with an episode of subacute LBP were tested at 3, 6, and 12 weeks following pain onset. Participants performed reaching tasks at comfortable and fast-paced movement speeds to 3 targets (high, middle, low) located in a midsagittal plane. Three-dimensional joint motions of the thoracic spine, lumbar spine, and hip were recorded using an electromagnetic tracking device. Group differences in joint excursions were assessed using 2 groups (high pain-related fear, low pain-related fear) x 3 times (3, 6, 12 weeks) x 2 movement speeds (comfortable, fast paced) x 3 target heights (high, middle, low) MANOVAs.

RESULTS

Individuals with high pain-related fear had smaller excursions of the lumbar spine for reaches to all targets at 3 and 6 weeks, but not at 12 weeks following pain onset.

CONCLUSION

Individuals with high pain-related fear adopt alternative movement strategies and avoid motion of the lumbar spine when performing a common reaching movement. Identifying how pain-related fear maps to actual motor behavior (i.e., alternative movement strategies) is a crucial first step in determining how pain-related fear and motor behavior interact to promote or delay recovery from acute low back pain.

Pain scores in the management of postoperative pain in shoulder surgery

PURPOSE

Recent public opinion has focused on the lay perception that postoperative pain control is inadequate. The Joint Commission on Accreditation of Healthcare Organizations has attempted to address this issue by mandating patient-reported numeric pain scores as part of postoperative pain assessment. No studies exist to validate these scores in orthopaedics. The purpose of this study was 3-fold: (1) to determine which preoperative variables were associated with elevated postoperative pain scores, (2) to identify whether pain scores correlated with more traditional signs and symptoms of pain, and (3) to identify whether patients with a high pain score (HPS) affect perioperative and postoperative complication rates.

METHODS

We retrospectively evaluated 105 patients who underwent routine arthroscopic rotator cuff repair over a 12-month period. Correlations and linear regression analysis were used to assess factors associated with postoperative pain scores. Logistic regression analysis was used to construct a model of preoperative, demographic, surgical, and postoperative variables associated with HPSs.

RESULTS

Wide variability existed in pain scores despite the similarity of the surgical stimulus. What subtle differences that were present in the surgical procedures had no bearing on pain scores. No correlation existed between pain scores and any physiologic correlate of pain. Pain scores were correlated with Workers' Compensation insurance, preoperative antianxiety medications, antidepressant medications, preoperative narcotics, and alcohol use. HPS patients had a longer recovery room stay (P < .05) and a higher incidence of postoperative nausea than those with a normal pain tolerance. HPS patients also had a significantly delayed return to work, as well as significantly lower Simple Shoulder Test scores at 6 weeks, although the final shoulder scores were similar to those in patients with a normal pain tolerance.

CONCLUSIONS

Patient-reported pain scores have been mandated, but they vary widely among patients undergoing virtually the same procedure and correlate poorly with physiologic manifestations of pain. Pain scores tend to correlate with other types of variables, most of which would be expected by the experienced surgeon. The exclusive use of pain scores in postoperative pain management should be limited to prevent complications.

LEVEL OF EVIDENCE

Level IV, prognostic case series.

Are functional capacity evaluations affected by the patient's pain?

Functional capacity evaluations (FCE) are comprehensive batteries of performance-based tests used commonly to inform return-to-work decisions for injured workers. As many people undergoing FCE have painful musculoskeletal conditions limiting their work ability, pain becomes a critical factor in the assessment of function. This paper considers the available literature related to the influence of pain on FCE, which clearly indicates FCEs are behavioral assessments influenced by pain intensity and other pain-related constructs. Increasing pain levels are consistently associated with reduced FCE performance levels. As such, for purposes of claims adjudication, FCE should not be considered a purely "objective" indicator of functional impairment independent of subject or evaluator perceptions. FCE may have some value for facilitating return-to-work or re-integrating chronically disabled workers into the workforce, although pain factors must be taken into consideration when making predictions about future work status. Shorter FCEs could potentially be as effective as more lengthy protocols.

Acute low back pain: pain-related fear and pain catastrophizing influence physical performance and perceived disability

Pain-related fear and pain catastrophizing are associated with disability and actual performance in chronic pain patients. In acute low back pain (LBP), little is known about the prediction of actual performance or perceived disability by pain-related fear and pain catastrophizing. This experimental, cross-sectional study aimed at examining whether pain-related fear and pain catastrophizing were associated with actual performance and perceived disability. Ninety six individuals with an episode of acute LBP performed a dynamic lifting task to measure actual performance. Total lifting time was used as outcome measure. The results show that pain-related fear, as measured with the Tampa Scale for Kinesiophobia, was the strongest predictor of this physical task. Using the Roland Disability Questionnaire as a measure of perceived disability, both pain-related fear and pain catastrophizing, as measured with the Pain Catastrophizing Scale, were significantly predictive of perceived disability and more strongly than pain intensity was. The results of the current study suggest that pain-related fear is an important factor influencing daily activities in individuals suffering an episode of acute LBP. The study results have important clinical implications, especially in the development of preventive strategies for chronic LBP.

Psychiatric comorbidity in fibromyalgia

This review examines the current literature regarding psychiatric comorbidities associated with fibromyalgia. The aim of this review is to enhance understanding of psychiatric disorders that, alone or in combination with other physiologic (eg, neuroendocrine dysfunction) and psychosocial factors (eg, poor coping skills), may contribute to abnormal pain sensitivity and other illness behaviors of individuals with fibromyalgia. The review first identifies the psychiatric comorbidities that are associated most often with fibromyalgia and tend to aggregate within families of individuals with this disorder. It then examines the literature regarding the extent to which psychiatric illness, environmental stressors, or other psychosocial factors may contribute to the development of fibromyalgia. The review also presents recent findings concerning the extent to which psychosocial factors may contribute to treatment-related outcomes in pain and other health status variables among patients with fibromyalgia.

Fear of movement/(re)injury in chronic low back pain: education or exposure in vivo as mediator to fear reduction?

Clinical research of graded exposure in vivo with behavioral experiments in patients with chronic low back pain who reported fear of movement/(re)injury shows abrupt changes in self-reported pain-related fears and cognitions. The abrupt changes are more characteristics of insight learning rather than the usual gradual progression of trial and error learning. The educational session at the start of the exposure might have contributed to this insight. The current study examines the contribution of education and graded exposure versus graded activity in the reduction of pain-related fear and associated disability and physical activity. Six consecutive patients with chronic low back pain who reported substantial fear of movement/(re)injury were included in the study. After a no-treatment baseline measurement period, all the patients received a single educational session, followed again by a no-treatment period. Patients were then randomly assigned to either a graded exposure with behavioral experiments or an operant graded activity program. A diary was used to assess daily changes in pain intensity, pain-related fear, pain catastrophizing, and activity goal achievement. Standardized questionnaires of pain-related fear, pain vigilance, pain intensity, and pain disability were administered before and after each intervention and at the 6-month follow-up. An activity monitor was carried at baseline, during the interventions, and 1 week at 6-month follow-up. Randomization tests of the daily measures showed that improvements in pain-related fear and catastrophizing occurred after the education was introduced. The results also showed a further improvement when exposure in vivo followed the no-treatment period after the education and not during the operant graded activity program. Performance of relevant daily activities, however, were not affected by the educational session and improved significantly only in the exposure in vivo condition. All improvements remained at half-year follow-up only in patients receiving the exposure in vivo. These patients also reported a significant decrease in pain intensity at follow-up.

The Fear of Pain questionnaire: factor structure in samples of young, middle-aged and elderly European people

The present study examined the factor structure of the Fear of Pain questionnaire in three independent samples composed of European young adults, middle-aged, and elderly people. Seven hundred and thirty one adults (426 females and 305 males) were presented with the French adaptation of the questionnaire (30 items) and with an Exposure to Painful Situations questionnaire that contained the same items as the Fear of Pain questionnaire and where participants were instructed to indicate all the painful situations they have experienced in the past. When tested on the whole set of 30 items, the correlated three-factor model evidenced in previous studies - Severe pain, Minor pain and Medical pain - poorly fit the data. When tested on a set of 15 two-item parcels, the fit of this model was much better but the correlations between factors were very high. When tested on a reduced set of 15 items, the model fit the data as well as when it was tested on the set of 15 parcels, and the correlations between the three factors were lower. The study also examined the link between previous exposure to pain and fear of pain. The hypothesis that previous "natural" exposure to pain should generally result in a decrease in fear of pain was supported by the data. For 14 items, the exposure effect was moderate to strong.

Cognitive factors influence outcome following multidisciplinary chronic pain treatment: a replication and extension of a cross-lagged panel analysis

Reducing maladaptive cognitions is hypothesized to constitute an active therapeutic process in multidisciplinary pain programs featuring cognitive-behavioral interventions. A cross-lagged panel design was used to determine whether: a) early-treatment cognitive changes predicted late-treatment pain, interference, activity and mood changes, but not vice versa; b) three cognitive factors made unique contributions to outcome; c) substantial cognitive changes preceded substantial improvements in outcome. Sixty-five chronic pain patients, participating in a 4-week multidisciplinary program, completed measures of pain helplessness, catastrophizing, pain-related anxiety (process factors), pain severity, interference, activity level and depression (outcomes) at pre-, mid- and posttreatment. Results showed that early-treatment reductions in pain helplessness predicted late-treatment decreases in pain and interference, but not vice versa, and that early-treatment reductions in catastrophizing and pain-related anxiety predicted late-treatment improvements in pain severity, but not vice versa. Findings suggested that the three process factors predicted improvements mostly in common. However, little evidence was found that large early-treatment reductions in process variables preceded extensive improvements in pain. Findings replicate those of a recent report regarding cross-lagged effects, and offer support that cognitive changes may indeed influence late-treatment changes in outcomes.

Pain anxiety among chronic pain patients: specific phobia or manifestation of anxiety sensitivity?

Rather than viewing anxiety among chronic pain patients as simply a component of negative affectivity, investigators have developed a model of "pain anxiety" in which patients develop fear and avoidance of activity linked to pain. We examined whether pain anxiety can be conceptualized as a specific phobia, or whether evidence supported the notion that pain anxiety is better understood as a manifestation of anxiety sensitivity in the context of chronic pain. Chronic musculoskeletal pain patients (N=70) underwent cold pressor and mental arithmetic tasks while cardiovascular, self-report, and behavior indexes were recorded. They completed measures of pain anxiety, anxiety sensitivity, fear of negative evaluation, depression and trait anxiety. Correlation analyses showed pain anxiety was related to pain-relevant responses during cold pressor, but it was also related to evaluation-relevant responses during cold pressor, and to pain- and evaluation-relevant responses (including subtraction accuracy) during mental arithmetic. Regression analyses showed that almost all effects of pain anxiety on task responses were accounted for by anxiety sensitivity. Fear of negative evaluation, in contrast, correlated only with evaluation-relevant responses, and mostly during mental arithmetic. These effects remained significant when depression, trait anxiety, or anxiety sensitivity were statistically controlled. Pain anxiety may be an expression of anxiety sensitivity rather than a circumscribed phobia; a distinction that could profitably guide treatment strategies.

The pain vigilance and awareness questionnaire (PVAQ): further psychometric evaluation in fibromyalgia and other chronic pain syndromes

In chronic pain patients, preoccupation with or attention to pain is associated with pain-related fear and perceived pain severity. The current study investigated psychometric properties of the pain vigilance and awareness questionnaire (PVAQ). An exploratory factor analysis on Dutch fibromyalgia patients indicated that a two-factor solution was most suitable. The first factor could be referred to as attention to pain and the second factor was interpreted as attention to changes in pain. A confirmatory factor analysis, testing three different factor structures in two independent samples (Dutch fibromyalgia patients and American pain patients with various diagnoses) showed that the goodness-of-fit indicators for all models were satisfactory. The existence of the previously reported intrusion subscale of the PVAQ as a unique construct within the PVAQ was discussed. This subscale should be further extended by non-reverse-keyed items. With regard to the convergent validity, the PVAQ was highly correlated with related constructs such as the pain catastrophizing scale (PCS), pain anxiety symptoms scale (PASS), and Tampa scale of kinesiophobia (TSK). The attention to pain subscale was significantly stronger associated with these pain-related measures than the attention to changes in pain subscale, indicating that attention to changes in pain is a distinctive construct. The uniqueness of the attention to changes in pain subscale was also supported by an exploratory factor analysis on all items of the PVAQ, PCS, PASS, and TSK which showed that all items from that scale loaded on one separate factor. Overall, the PVAQ showed good internal consistency. Implications for future research and treatment interventions are discussed.

Work-related beliefs about injury and physical capability for work in individuals with chronic pain

According to a fear-avoidance model of chronic pain, disability is largely determined by the erroneous belief that an increase in activity level is potentially harmful. Further, recent literature suggests that excessive fears regarding physical activities contribute to significant disability. However, the relation of changes in these fears to functional work capabilities has gone largely uninvestigated. The present study examined how changes in physical capability for work were related to changes in pain severity and fear-avoidance beliefs for general physical and work-specific activities, as well as investigating whether an interdisciplinary treatment program for chronic pain was associated with changes in these specific fears in 65 individuals with chronic pain. Results revealed that significant decreases in fear and pain levels occurred from pre- to post-treatment, in addition to increases in physical capability for work. Further, changes in work-specific fears were more important than changes in pain severity and fear of physical activity in predicting improved physical capability for work. These results expand previous research, which has found a relation between self-reported disability and fear-avoidance beliefs, by demonstrating the relation with fear of work to actual work-related behaviors.

Affective analgesia following the administration of morphine into the amygdala of rats

The amygdala processes stimuli that threaten the individual and organizes the execution of affective behaviors that permit the individual to cope with the threat. The prototypical threat to an individual is exposure to a noxious stimulus. The present study evaluated the contribution of the amygdala in modulating the affective response of rats to noxious stimulation. Vocalization afterdischarges (VADs) are a validated model of the affective response of rats to noxious tailshock. The antinociceptive action of morphine microinjected into the amygdala on VAD thresholds was compared to its effect on the thresholds of other tailshock-elicited responses (vocalizations during shock, VDS and spinal motor reflexes, SMRs). Whereas VADs are organized within the forebrain, VDSs and SMRs are organized at medullary and spinal levels of the neuraxis, respectively. The bilateral administration of morphine into the basolateral complex of the amygdala (BLC) produced dose-dependent increases in VAD and VDS thresholds, although increases in VAD thresholds were significantly greater than increases in VDS thresholds. Administration of morphine into BLC was ineffective in elevating SMR thresholds. Morphine-induced increases in vocalization thresholds were reversed in a dose-dependent manner by microinjection of the opiate receptor antagonist methylnaloxonium into BLC. Microinjection of morphine in the vicinity to the BLC did not alter vocalization thresholds. The present results provide further evidence for the preferential involvement of the amygdala in modulation of the affective component of the pain experience.

The treatment of fear of movement/(re)injury in chronic low back pain: further evidence on the effectiveness of exposure in vivo

BACKGROUND AND OBJECTIVE

Several cognitive-behavioral factors contribute to the persistence of pain disability in patients with chronic back pain. Fear-avoidance beliefs and fear of movement/(re)injury in particular have been shown to be strong predictors of physical performance and pain disability. Patients reporting substantial pain-related fear might benefit from exposure in vivo to a set of individually tailored, fear-eliciting, and hierarchically ordered physical movements rather than more general graded activity.

PATIENTS AND INTERVENTIONS

Six consecutive patients with chronic low back pain who reported substantial fear of movement/(re)injury were included in the study. After a no-treatment baseline measurement period, the patients were randomly assigned to one of two interventions. In the first intervention, patients received exposure in vivo first, followed by graded activity. In the second intervention, the sequence of treatment modules was reversed. Before each treatment module, treatment credibility was assessed. Daily measures of pain-related fear, pain catastrophizing, and pain intensity were completed using visual analog scales. In addition, standardized measures of pain disability, pain-related fear, and pain vigilance were taken before and after each treatment module and at the 1-year follow-up. To obtain more objective data on actual activity levels, an ambulatory activity monitor was carried by the patients during 1 week before and after each treatment module.

RESULTS

Time series analysis of the daily measures showed that improvements in pain-related fear and pain catastrophizing occurred only during the exposure in vivo and not during the graded activity, irrespective of the treatment order. Analysis of the pretreatment to post-treatment differences also revealed that decreases in pain-related fear also concurred with decreases in pain disability and pain vigilance and an increase in physical activity levels. All improvements remained at the 1-year follow-up.

Multimethod assessment of treatment process in chronic low back pain: comparison of reported pain-related anxiety with directly measured physical capacity

Although cognitive behavioural treatments (CBT) have proven efficacy in improving symptom management, pain-related distress, physical performance and return to work. few studies have examined the relationship between changes in behavioural process variables during treatment and improvement in outcome variables following treatment. We designed a multimethod assessment strategy to test the relative contribution of changes in physical capacity and pain-related anxiety to treatment outcome variables. Low back pain patients (n = 59) were treated with an intensive programme of physical exercise and CBT. Comparisons from pre- to post-treatment showed significant improvement in pain severity, interference, affective distress, activity level, and depression. Improvements in pain-related anxiety were associated with improvements in all outcome variables except interference. Of three physical capacity composite scores, improvement in only one (lumbar extension and flexion capacity) was associated with improvements in all outcome variables except interference. Further analyses demonstrated that the relationship between changes in pain-related anxiety and treatment outcome were independent of changes in physical capacity performance. Changes during treatment in pain-related anxiety may be more important than changes during treatment in physical capacity when predicting the effect of treatment on behavioural outcome measures. These results are discussed in the context of how to improve assessment of the chronic pain patient and improve the effectiveness of multidisciplinary CBT.

Psychological assessment and treatment of patients with neuropathic pain

Studies on the psychological assessment and treatment of neuropathic pain conditions, including postherpetic neuralgia (PHN), diabetic neuropathy, complex regional pain syndrome, post spinal cord injury, post amputation, and AIDS-related neuropathy, are reviewed. Although limited information is currently available, the findings are consistent with the larger literature on chronic pain and indicate that the assessment of neuropathic pain needs to include measurement of multiple dimensions of quality of life. Mood, physical and social functioning, and pain-coping strategies such as catastrophizing and social support are all important domains. Clinical trials of psychological interventions have not been reported in the scientific literature. Case series of successful treatment of neuropathic pain are reported, primarily in the area of biofeedback. As with other chronically painful conditions, it is likely that cognitive-behavioral interventions will improve the quality of life in neuropathic pain conditions.