Pain Anxiety Symptoms Scale

Abstract

The Pain Anxiety Symptoms Scale (PASS), developed by Lance M. McCracken and colleagues in 1992, is an established 40-item self-report psychometric instrument designed to measure pain-specific anxiety and fear across multiple response channels. Emerging from the necessity to distinguish general affective distress from maladaptive cognitive, behavioral, and physiological reactions directly elicited by pain sensations, the PASS operationalizes pain anxiety through four empirically derived 10-item subscales: Cognitive Anxiety, Escape/Avoidance, Fearful Thinking (also designated as Fear), and Physiological Symptoms. Respondents evaluate the frequency of their reactions on a 6-point rating scale ranging from 0 (never) to 5 (always), yielding subscale scores between 0 and 50 and a composite total score ranging from 0 to 200, with higher scores reflecting elevated levels of pain-related anxiety.

Extensive psychometric investigations have affirmed the high internal consistency of the PASS, with full-scale Cronbach’s alpha coefficients consistently falling between α = .94 and .96 across clinical chronic pain populations, and individual subscale coefficients ranging from α = .81 to .92. Confirmatory and exploratory factor analyses support both an oblique four-factor structure and a higher-order overarching general factor, corroborating its theoretical alignment with the Fear-Avoidance Model of Chronic Pain. The instrument exhibits robust convergent validity through moderate-to-strong correlations with the Pain Catastrophizing Scale (PCS), the Tampa Scale for Kinesiophobia (TSK), and general anxiety metrics such as the Beck Anxiety Inventory (BAI), while demonstrating critical discriminant validity in predicting pain-induced functional impairment, avoidance behavior, and somatic hypervigilance above and beyond objective physical pathology or generalized trait neuroticism.

Keywords

Pain Anxiety Symptoms Scale, PASS, pain-related anxiety, chronic pain assessment, fear-avoidance model, kinesiophobia, cognitive anxiety, behavioral avoidance, psychometrics, pain catastrophizing

Authors

The Pain Anxiety Symptoms Scale was developed by clinical psychologist and behavioral medicine researcher Lance M. McCracken, Ph.D., along with collaborators Charles P. Zayfert, Ph.D., and Roy T. Gross, Ph.D.

• Lance M. McCracken, Ph.D. — Professor of Clinical Psychology and Head of the Division of Clinical Psychology at Uppsala University (Sweden), formerly Professor of Behavioral Medicine at King’s College London and Consultant Clinical Psychologist at the Royal National Hospital for Rheumatic Diseases in Bath, United Kingdom. Dr. McCracken is an internationally recognized authority on chronic pain rehabilitation, psychological flexibility, contextual cognitive-behavioral science, and Acceptance and Commitment Therapy (ACT).
• Charles P. Zayfert, Ph.D. — Clinical Psychologist and former Associate Professor of Psychiatry at the Geisel School of Medicine at Dartmouth College, renowned for expertise in cognitive-behavioral therapy for anxiety disorders, trauma, and somatic interactions.
• Roy T. Gross, Ph.D. — Professor and clinical researcher affiliated with the Department of Behavioral Medicine and Psychiatry at West Virginia University School of Medicine, focusing on behavioral interventions in pain management, functional spinal disorders, and clinical assessment methodologies.

Purpose

The fundamental clinical and empirical purpose of the Pain Anxiety Symptoms Scale is to quantify the cognitive, behavioral, and somatic dimensions of anxiety evoked specifically by persistent or anticipated physical pain. Prior to the development of the PASS in the early 1990s, clinicians and researchers relied predominantly on generic psychological distress inventories, such as the State-Trait Anxiety Inventory (STAI), the Symptom Checklist-90-Revised (SCL-90-R), or the Beck Anxiety Inventory (BAI). While these instruments adequately capture generalized trait vulnerability or autonomic nervous system hyperactivity, they consistently fail to account for the unique stimulus properties of pain as an unconditioned or conditioned signal of biological threat. Consequently, clinicians were unable to differentiate whether a patient’s elevated anxiety represented premorbid constitutional distress or a localized, functional phobic reaction to somatic sensations.

The PASS addresses this diagnostic and functional limitation by evaluating pain-related anxiety as a multidimensional phenomenon situated within contemporary cognitive-behavioral paradigms. In tertiary pain clinics, orthopedic rehabilitation programs, and rheumatological settings, the instrument fulfills several critical operational roles:

• Baseline Diagnostic Screening: Identifying patients who demonstrate excessive affective reactivity and catastrophic cognitive appraisals, which elevate the risk of transition from acute tissue injury to disabling chronic pain syndromes.
• Treatment Customization and Stratification: Differentiating patients whose primary functional barrier is cognitive rumination and attentional disruption from those driven by pervasive behavioral escape, fear of physical movement (kinesiophobia), or acute panic-like autonomic hyperarousal.
• Outcome Monitoring in Interdisciplinary Rehabilitation: Evaluating therapeutic responsiveness to targeted interventions, including graded in vivo exposure, cognitive restructuring, interoceptive exposure, functional restoration, and Acceptance and Commitment Therapy (ACT).
• Empirical Research into Pain Neurophysiology: Providing an operationalized measure of psychological threat appraisal to examine pain modulation pathways, including descending pain facilitatory mechanisms, central sensitization, and attentional allocation during nociceptive stimulation.

Psychological Construct

Pain-related anxiety, as operationalized by the PASS, refers to the multifaceted constellation of cognitive, emotional, physiological, and behavioral responses triggered by the perception or anticipation of pain. Rather than treating pain distress as a homogeneous, unidimensional entity, the PASS divides the construct into four distinct yet interrelated response channels, each consisting of 10 items scored from 0 to 5:

1. Cognitive Anxiety (Items 1, 7, 9, 13, 15, 17, 24, 28, 30, 39)

The Cognitive Anxiety subscale evaluates the cognitive interference, executive dysfunction, and mental fragmentation experienced by individuals during pain episodes. When pain is appraised as an imminent threat, it demands immediate attentional allocation, depleting central executive working memory resources. This subscale measures subjective complaints regarding the inability to concentrate, memory retrieval failures, mental disorientation, and feelings of losing cognitive control. Prototypic items include “I can’t think straight when I am in pain” (Item 1), “My mind goes blank when pain begins” (Item 9), and “Pain makes it hard to make decisions” (Item 39). High scores on this dimension reflect severe disruption of executive cognitive processing caused by the intrusive nature of nociceptive stimuli.

2. Escape/Avoidance (Items 3, 5, 11, 14, 18, 20, 22, 26, 32, 34)

The Escape/Avoidance subscale captures overt behavioral responses aimed at terminating or circumventing pain sensations. Grounded in operant conditioning and behavioral avoidance paradigms, this dimension quantifies the extent to which an individual preemptively terminates daily physical tasks, retreats to sedentary resting postures, cancels planned activities, seeks immediate emergency medical intervention, or consumes pharmacological agents at the earliest detection of physical discomfort. Characteristic statements include “I will stop an activity when I feel the first sign of pain coming on” (Item 3), “I immediately lay down or rest when I feel pain coming on” (Item 11), and “I try to avoid situations that might cause pain” (Item 26). While these behaviors provide short-term negative reinforcement by reducing immediate distress, over time they foster physical deconditioning, secondary disuse syndrome, and psychological disability.

3. Fearful Thinking (Fear) (Items 2, 4, 12, 19, 21, 23, 27, 31, 35, 37)

The Fearful Thinking subscale assesses the cognitive appraisal of pain as catastrophic, dangerous, and indicative of progressive somatic injury or permanent disability. This subscale operationalizes the cognitive misinterpretation of benign nociception as an index of profound bodily pathology, unremitting deterioration, or impending physical paralysis. Representative items include “I think that every pain is a sign of new damage” (Item 4), “I worry that my pain will cause me to become disabled” (Item 21), “I think that my pain will never get better” (Item 27), and “I am afraid to move when I am in pain” (Item 31). This dimension overlaps conceptually with pain catastrophizing, particularly magnification and helplessness, reflecting a cognitive vulnerability that amplifies fear responses.

4. Physiological Symptoms (Items 6, 8, 10, 16, 25, 29, 33, 36, 38, 40)

The Physiological Symptoms subscale quantifies perceived autonomic reactivity and sympathetic nervous system activation provoked by pain onset or anticipation. This subscale addresses bodily reactions driven by the fight-or-flight response, including tachycardia, tachypnea, peripheral vasoconstriction, diaphoresis, dizziness, muscular bracing, and gastrointestinal distress. Items measuring this dimension include “Pain makes my heart race” (Item 8), “When I feel pain I become sweaty or hot” (Item 25), “Pain causes my muscles to tense up” (Item 29), and “When I feel pain I feel like I can’t catch my breath” (Item 40). Muscle bracing and hyperventilation can paradoxically exacerbate nociceptive input by increasing muscular ischemia, creating a self-perpetuating cycle of pain and physiological activation.

Theoretical Framework

The Pain Anxiety Symptoms Scale is anchored within cognitive-behavioral models of chronic illness, most notably the Fear-Avoidance Model of Chronic Pain articulated by Johan W. S. Vlaeyen, Steven J. Linton, Geert Crombez, and Gordon J. G. Asmundson. This framework explains why a significant subset of individuals suffering from acute musculoskeletal episodes fail to recover, instead transitioning into chronic, disabling pain conditions characterized by severe psychological distress and functional impairment.

According to this model, when an individual experiences acute nociception, the trajectory of functional recovery diverges based on cognitive appraisal. If the pain is appraised as non-threatening and manageable, the individual maintains engagement in normal activities, promoting tissue healing, functional restoration, and rapid recovery. However, if the pain is interpreted through catastrophic cognitive appraisals (evaluated by the Fearful Thinking subscale of the PASS), the individual develops pain-related fear and anxiety. This affective reaction is manifested through subjective cognitive disruption (Cognitive Anxiety), heightened sympathetic arousal and muscular bracing (Physiological Symptoms), and persistent behavioral withdrawal (Escape/Avoidance).

The theoretical architecture of the PASS also draws upon David Barlow’s Triple Vulnerability Model of emotional disorders, which posited that specialized anxiety disorders arise from the convergence of general biological vulnerabilities, generalized psychological vulnerabilities, and specific learned psychological vulnerabilities. In chronic pain populations, the PASS isolates this specific psychological vulnerability: the learned perception that somatic sensations represent uncontrollable, catastrophic threats demanding avoidance. Furthermore, the scale integrates functional operant principles established by Wilbert Fordyce, wherein avoidance behaviors are maintained through short-term negative reinforcement (the temporary reduction of pain or fearful anticipation), which ultimately leads to physical deconditioning, depressive isolation, loss of positive reinforcement, and heightened sensitivity to pain.

Validity

Psychometric evaluations have demonstrated the construct, convergent, discriminant, and predictive validity of the Pain Anxiety Symptoms Scale across diverse clinical cohorts, including patients with chronic low back pain, fibromyalgia, neuropathic pain, and general musculoskeletal disorders.

Construct and Structural Validity

Construct validity was established by McCracken et al. (1992, 1993) through exploratory factor analyses, confirming that the 40 items load onto four distinct, clinically interpretable factors. Subsequent confirmatory factor analyses (CFA) across diverse international cohorts have validated both a four-factor correlated model and a hierarchical model in which four first-order factors load onto a general pain-related anxiety construct. Goodness-of-fit indices across published structural evaluations consistently show robust comparative fit indices (CFI > .90, TLI > .90) and acceptable root mean square errors of approximation (RMSEA ≤ .06 to .08).

Convergent Validity

The PASS demonstrates strong convergent validity with established measures of pain-related cognitive appraisals and affective distress:

• Pain Catastrophizing Scale (PCS): Demonstrates strong positive correlations with the PASS total score (typically ranging between r = .65 and r = .78), with the strongest associations observed for the Fearful Thinking subscale.
• Tampa Scale for Kinesiophobia (TSK): Demonstrates moderate-to-high correlations with PASS scores (r = .50 to .68), particularly with the Escape/Avoidance subscale, confirming its sensitivity to fear of movement and reinjury.
• General Anxiety Measures: Correlates moderately with the Beck Anxiety Inventory (r = .48 to .60) and the State-Trait Anxiety Inventory Trait Scale (r = .42 to .55), supporting the hypothesis that pain anxiety shares common variance with generalized neurotic distress while maintaining distinct diagnostic boundaries.

Discriminant Validity

Crucially, the PASS demonstrates discriminant validity by predicting clinical outcomes independently of general negative affectivity. In hierarchical regression analyses, the PASS accounts for significant incremental variance in pain intensity, physical disability, range of motion limitations, and medication consumption after statistically controlling for general trait anxiety (STAI), depression (Beck Depression Inventory), and demographic variables. This confirms that the PASS measures a specific clinical construct distinct from generalized emotional distress or negative affectivity.

Predictive and Criterion Validity

Prospective and cross-sectional investigations show that baseline PASS total and subscale scores predict functional disability (as measured by the Roland-Morris Disability Questionnaire and the Oswestry Disability Index), daily downtime, vocational absenteeism, and avoidance during physical capacity evaluations. In experimental cold pressor and physical loading paradigms, elevated PASS scores predict decreased pain tolerance, heightened subjective pain ratings, and prolonged recovery latencies.

Reliability

The PASS demonstrates robust internal consistency and temporal stability across diverse clinical and empirical investigations.

Internal Consistency

In the original validation study by McCracken, Zayfert, and Gross (1992) involving chronic pain patients admitted to an interdisciplinary rehabilitation program, the scale exhibited high internal reliability coefficients:

• Total PASS Score: Cronbach’s α = .94
• Cognitive Anxiety Subscale: Cronbach’s α = .87
• Escape/Avoidance Subscale: Cronbach’s α = .86
• Fearful Thinking Subscale: Cronbach’s α = .88
• Physiological Symptoms Subscale: Cronbach’s α = .81

Subsequent psychometric evaluations across varied chronic pain populations have replicated these high internal consistency metrics, with total scale Cronbach’s alphas consistently ranging from .94 to .96, and subscale alphas spanning .81 to .92. Mean inter-item correlations within subscales typically range between .35 and .55, indicating balanced construct coverage without excessive item redundancy.

Test-Retest Stability

Investigations examining the temporal stability of the PASS in stable chronic pain cohorts over test-retest intervals ranging from one to three weeks demonstrate intraclass correlation coefficients (ICCs) between .80 and .88 for the total score, and between .74 and .84 for the four individual subscales. In longitudinal intervention studies, the PASS exhibits sensitivity to clinical change, showing statistically significant and clinically meaningful score reductions following successful cognitive-behavioral and interdisciplinary functional restoration programs.

Factor Analysis

The internal structural validity of the PASS has been investigated through both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA).

Exploratory Factor Structure

In the initial development study, McCracken et al. (1992) conducted a principal components analysis with oblique rotation on an initial pool of candidate items administered to chronic pain patients. The empirical extraction yielded a four-factor solution that accounted for 43.8% of the total variance. Factor loadings for each of the 10 assigned items per subscale were uniformly robust, exceeding the .40 threshold with minimal cross-loadings. The identified factors corresponded directly to the theoretical dimensions: Cognitive Anxiety, Escape/Avoidance, Fearful Thinking, and Physiological Symptoms.

Confirmatory Factor Models

Subsequent CFA studies (e.g., Osman et al., 2002; Roelofs et al., 2004) compared competing structural configurations across both clinical and non-clinical populations:

• Unidimensional Model: Posits that all 40 items reflect a single homogeneous pain anxiety factor. Across all investigations, this model demonstrated poor fit (e.g., CFI < .80, RMSEA > .10), confirming the necessity of a multidimensional framework.
• Four-Factor Orthogonal Model: Assumed four completely independent dimensions. This model was rejected due to significant empirical intercorrelations among the subscales (r = .45 to .75).
• Four-Factor Correlated Model: Hypothesizes four distinct but interrelated first-order latent constructs. This model demonstrated adequate-to-good fit across diverse demographic and clinical samples (CFI > .90, TLI > .90, RMSEA ≈ .055–.072).
• Hierarchical / Higher-Order Model: Specifies a overarching second-order “Pain-Related Anxiety” factor that accounts for the covariance among the four first-order factors. This model yielded fit indices comparable to the correlated four-factor model, validating the clinical practice of reporting both individual subscale profiles and a single composite score.

These structural findings subsequently informed the development of the widely used 20-item short form, the PASS-20 (McCracken & Dhingra, 2002), which retained the 5 highest-loading items from each of the original four subscales, preserving the original factor structure while reducing respondent burden.

Instrument / Measurement Tool

• Full Instrument Name: Pain Anxiety Symptoms Scale (PASS; also referenced as PASS-40)
• Original Language: English
• Instrument Type: Multidimensional self-report rating scale
• Administration Format: Paper-and-pencil questionnaire, digital/electronic survey, or clinician-facilitated interview
• Target Population: Adult and elderly individuals suffering from acute, subacute, or persistent chronic pain conditions
• Completion Time: Approximately 8 to 12 minutes
• Total Item Count: 40 items
• Response Scale: 6-point rating scale from 0 (never) to 5 (always):
  • 0 = Never
  • 1 = Once in a while
  • 2 = Sometimes
  • 3 = Fairly often
  • 4 = Very often
  • 5 = Always
• Subscale Structural Breakdown (10 items per subscale):
  • Cognitive Anxiety: Items 1, 7, 9, 13, 15, 17, 24, 28, 30, 39
  • Escape/Avoidance: Items 3, 5, 11, 14, 18, 20, 22, 26, 32, 34
  • Fearful Thinking (Fear): Items 2, 4, 12, 19, 21, 23, 27, 31, 35, 37
  • Physiological Symptoms: Items 6, 8, 10, 16, 25, 29, 33, 36, 38, 40
• Scoring and Computational Rules:
  • Reverse Scored Items: None. All items are positively keyed toward pain-related anxiety.
  • Subscale Score Calculation: Direct summation of the 10 respective items for each domain. Subscale score range: 0 to 50.
  • Total Score Calculation: Summation of all 40 items (or summation of the 4 subscale totals). Total score range: 0 to 200.
  • Interpretation: Higher scores denote greater pain-related anxiety, catastrophic apprehension, avoidance behavior, and physiological hyperreactivity. Total scores exceeding 100 typically indicate clinically elevated pain-related anxiety warranting targeted psychological intervention.

Permissions & Fee and Test Year

The Pain Anxiety Symptoms Scale was initially published in 1992 in the academic journal Behavior Therapy. The scale was developed with academic and non-commercial clinical dissemination in mind. It is widely accessible within the public domain for research, academic investigations, and routine non-commercial clinical practice without payment of royalty fees, provided appropriate scholarly attribution is maintained. Commercial applications, inclusion in proprietary digital health technologies, or large-scale institutional software integration typically require formal permission from the primary author (Lance M. McCracken) or the copyright-holding publisher (Association for Behavioral and Cognitive Therapies / Elsevier). Researchers and clinicians are advised to cite the seminal 1992 validation paper in all resulting scientific reports.

References

• Asmundson, G. J. G., Norton, P. J., & Vlaeyen, J. W. S. (2004). Fear-avoidance models of chronic pain: An overview. In G. J. G. Asmundson, J. W. S. Vlaeyen, & G. Crombez (Eds.), Understanding and treating fear of pain (pp. 3–24). Oxford University Press. https://doi.org/10.1093/med:psych/9780198525349.003.0001
• Crombez, G., Vlaeyen, J. W. S., Heuts, P. H. T. G., & Lysens, R. (1999). Pain-related fear is more disabling than pain itself: Evidence on the role of pain-related fear in chronic back pain disability. Pain, 80(1–2), 329–339. https://doi.org/10.1016/S0304-3959(98)00229-2
• McCracken, L. M., & Dhingra, L. (2002). A short version of the Pain Anxiety Symptoms Scale (PASS-20): Preliminary development and validity. Pain Research and Management, 7(1), 45–50. https://doi.org/10.1155/2002/517163
• McCracken, L. M., Gross, R. T., Sorg, P. J., & Edmands, T. A. (1993). Prediction of pain in patients with chronic low back pain: Effects of inaccurate prediction and anxiety. Behaviour Research and Therapy, 31(7), 647–652. https://doi.org/10.1016/0005-7967(93)90117-6
• McCracken, L. M., Zayfert, C., & Gross, R. T. (1992). The Pain Anxiety Symptoms Scale: Development and validation of a scale to measure fear of pain. Behavior Therapy, 23(4), 585–598. https://doi.org/10.1016/S0005-7894(05)80222-6
• Osman, A., Barrios, F. X., Gutierrez, P. M., Kopper, B. A., Merrifield, T., & Grittmann, L. (2002). The Pain Anxiety Symptoms Scale-20: Psychometric properties in nonclinical and pain patient samples. Journal of Behavioral Medicine, 25(3), 235–250. https://doi.org/10.1023/A:1015308801980
• Roelofs, J., McCracken, L. M., Peters, M. L., Crombez, G., van Breukelen, G., & Vlaeyen, J. W. S. (2004). Psychometric evaluation of the Pain Anxiety Symptoms Scale (PASS) in chronic pain patients. Journal of Behavioral Medicine, 27(2), 167–183. https://doi.org/10.1023/B:JOBM.0000019850.57500.52
• Vlaeyen, J. W. S., & Linton, S. J. (2000). Fear-avoidance and its consequences in chronic musculoskeletal pain: A state of the art. Pain, 85(3), 317–332. https://doi.org/10.1016/S0304-3959(99)00242-0
• Vlaeyen, J. W. S., & Linton, S. J. (2012). Fear-avoidance model of chronic musculoskeletal pain: 12 years on. Pain, 153(6), 1144–1147. https://doi.org/10.1016/j.pain.2011.12.009

13. Items of the Scale (Questionnaire)