Secondary Traumatic Stress Scale

Abstract

The Secondary Traumatic Stress Scale (STSS) is a widely utilized 17-item self-report psychometric instrument designed to assess the frequency of indirect traumatic stress symptoms among professionals exposed to traumatized populations. Developed by Brian E. Bride, Marmian R. Robinson, Bonnie Yegidis, and Charles R. Figley in 2004, the instrument operationalizes secondary traumatic stress (STS) using diagnostic criteria parallel to the DSM-IV framework for Post-Traumatic Stress Disorder (PTSD). The scale evaluates three core symptom clusters across distinct subscales: Intrusion (5 items), Avoidance (7 items), and Arousal (5 items). Respondents rate the frequency with which they have experienced each symptom over the previous eight days using a 5-point Likert-type response format ranging from 1 (Never) to 5 (Very Often).

Extensive psychometric investigations have demonstrated robust internal consistency for the STSS, with overall scale Cronbach’s alpha coefficients consistently reported at or above α = .93, and subscale coefficients ranging from .80 to .87 (Intrusion α = .80, Avoidance α = .87, Arousal α = .83 in the initial validation cohort). Construct, convergent, and discriminant validities have been substantiated through strong correlations with secondary trauma exposure, burnout, compassion fatigue, general psychological distress, and distinct divergence from unrelated psychological constructs. Confirmatory factor analyses (CFA) across diverse human service samples—including social workers, healthcare practitioners, mental health counselors, child welfare professionals, and emergency responders—consistently corroborate the theoretical three-factor correlated structure, alongside empirical support for a higher-order overarching general factor. The STSS remains one of the gold-standard measurement tools in occupational health psychology, traumatology, and social work research.

Keywords

Secondary Traumatic Stress Scale, STSS, secondary traumatic stress, vicarious traumatization, compassion fatigue, intrusion, avoidance, physiological arousal, psychometrics, occupational trauma

Authors

The Secondary Traumatic Stress Scale was conceptualized, designed, and psychometrically validated by an interdisciplinary team of leading traumatology and social work scholars:

• Brian E. Bride, Ph.D., MSW, MPH: Distinguished University Professor and Director of the School of Social Work at Georgia State University (formerly at the University of Georgia School of Social Work). Dr. Bride is an internationally recognized authority on secondary traumatic stress, behavioral healthcare workforce development, and substance use disorders.
• Marmian R. Robinson, Ph.D., MSW: Clinical social work researcher and educator with foundational contributions to clinical assessment, trauma exposure among human service providers, and social work interventions.
• Bonnie L. Yegidis, Ph.D., MSW: Professor and former Director of the School of Social Work at the University of Central Florida; widely recognized for scholarship in research methodology, social work administration, and family violence.
• Charles R. Figley, Ph.D.: Paul Henry Kurzweg, Ph.D. Chair in Disaster Mental Health and Associate Dean for Research at the Tulane University School of Social Work; founder of the Traumatology Institute and a pioneer in the conceptualization of secondary trauma, compassion fatigue, and systemic family traumatology.

Purpose

The primary purpose of the Secondary Traumatic Stress Scale is to assess and quantify the psychological impact of indirect, vicarious exposure to traumatic events among service professionals who work with traumatized client populations. Professionals including clinical social workers, psychotherapists, emergency department personnel, disaster response workers, child protective services caseworkers, and forensic investigators are regularly exposed to detailed narratives, visual evidence, and emotional suffering associated with catastrophic events, interpersonal violence, child abuse, and life-threatening crises. While these professionals may not experience primary trauma firsthand, chronic indirect exposure can yield a debilitating syndrome phenomenologically identical to primary post-traumatic stress disorder.

Historically, the traumatology literature lacked a targeted, standardized, and clinically rigorous psychometric instrument specifically designed to operationalize STS according to established diagnostic symptom criteria. Earlier measures often conflated secondary traumatic stress with broader constructs such as occupational burnout, general workplace dissatisfaction, depression, or overall compassion fatigue. The STSS was engineered to resolve this diagnostic ambiguity by deliberately anchoring its items to clinical work with clients, thereby isolating symptoms that arise explicitly from secondary exposure rather than general organizational stress or unrelated personal life events.

In research environments, the STSS enables investigators to examine the prevalence, etiology, risk factors, and organizational correlates of secondary trauma across various disciplines. It allows for the empirical evaluation of workplace wellness initiatives, specialized clinical supervision models, peer support mechanisms, and psychoeducational training programs. In organizational and clinical contexts, the STSS functions as an indispensable self-monitoring and screening instrument. It alerts supervisors and clinicians to escalating levels of intrusion, cognitive and behavioral avoidance, and neurobiological arousal before these symptoms precipitate clinical impairment, functional absenteeism, professional turnover, or compromised client care.

Psychological Construct

The STSS operationalizes Secondary Traumatic Stress (STS), defined as a syndrome of symptoms mirroring Post-Traumatic Stress Disorder that results directly from knowledge of a traumatizing event experienced by a significant other or client and the emotional resonance generated through empathetic engagement. The construct is articulated through three distinct yet interrelated psychological dimensions aligned with diagnostic criteria:

1. Intrusion

The Intrusion dimension (measured by 5 items) represents involuntary, recurrent, and distressing cognitive, perceptual, and physiological re-experiencing of the client’s traumatic material. Helping professionals experiencing intrusive symptoms find their mental processes repeatedly invaded by aspects of the narratives, clinical histories, or catastrophic losses disclosed by their clients. This manifest phenomenology includes:

• Spontaneous, unbidden thoughts regarding client traumas occurring outside clinical work environments (e.g., during domestic activities, leisure, or rest).
• Disturbing, recurrent nightmares or dreams reflecting themes of victimization, threat, or helplessness directly tied to work contexts.
• Acute physiological reactivity (such as tachycardia, diaphoresis, or muscle tension) upon encountering reminders of client trauma.
• Dissociative re-experiencing states wherein the clinician subjectively feels as though they are re-living the traumatic events narrated by the client.

2. Avoidance

The Avoidance dimension (measured by 7 items) captures active cognitive, affective, and behavioral strategies employed by the individual to circumvent trauma-related stimuli, suppress emotional distress, or detach from ongoing professional demands. Because confronting traumatic content generates intense discomfort, clinicians unconsciously or consciously adopt defensive maneuvers to protect emotional equilibrium. Manifestations include:

• Deliberate behavioral avoidance of specific clients, clinical case files, case conferences, or physical settings associated with disturbing narratives.
• Psychological avoidance through emotional numbing, constricted affect, and an inability to experience positive emotional states.
• Psychological detachment, diminished interest in interpersonal relationships, and progressive withdrawal from colleagues, family, and social networks.
• Psychogenic or trauma-induced memory gaps regarding specific segments of client sessions, functioning as an involuntary dissociative defense against overwhelming secondary exposure.

3. Arousal

The Arousal dimension (measured by 5 items) denotes persistent, neurobiologically mediated states of sympathetic hyperarousal and physiological reactivity resulting from indirect trauma exposure. Persistent vicarious trauma primes the central nervous system for threat detection, leading to tonic disruption of the autonomic nervous system. Specific indicators assessed include:

• Sleep architecture disruption, including initial insomnia, frequent nocturnal awakenings, or unrefreshing sleep driven by heightened vigilance.
• Hypervigilance and exaggerated startle response (“jumpiness”) in response to benign environmental stimuli.
• Impaired executive functioning, specifically difficulty sustaining attention and concentrating on professional tasks.
• Affective dysregulation, generalized irritability, heightened annoyance, and pervasive cognitive expectations of impending catastrophe.

Theoretical Framework

The Secondary Traumatic Stress Scale is grounded in two primary theoretical foundations: Charles Figley’s Compassion Fatigue / Secondary Traumatic Stress Theory (1995) and the cognitive-phenomenological diagnostic formulation of Post-Traumatic Stress Disorder codified by the American Psychiatric Association in the DSM-IV.

Figley conceptualized secondary traumatic stress as “the natural consequent behaviors and emotions resulting from knowing about a traumatizing event experienced by a significant other—the stress resulting from helping or wanting to help a traumatized or suffering person.” Central to this theoretical architecture is the empathy paradox: empathy is the essential vehicle for establishing effective therapeutic rapport and facilitating healing; however, that same empathic attunement makes the clinician vulnerable to absorbing the client’s emotional pain, terror, and grief. According to Figley’s transmission model, the clinician internalizes the affective residue of the client’s traumatic narrative. Over prolonged periods without adequate cognitive integration, recovery periods, or structural boundaries, this vicarious absorption crystallizes into secondary traumatic stress.

Bride and colleagues (2004) synthesized Figley’s conceptual framework with the formal psychiatric symptomatology of PTSD. While McCann and Pearlman’s (1990) construct of Vicarious Traumatization emphasizes chronic cognitive shifts—alterations in basic cognitive schemas regarding safety, trust, esteem, intimacy, and control—Bride et al. asserted that secondary traumatization also manifests as an acute to chronic symptom complex identical to primary PTSD. Consequently, they adopted the DSM-IV tripartite symptom architecture—Criterion B (Intrusive Re-experiencing), Criterion C (Persistent Avoidance and Numbing), and Criterion D (Persistent Symptoms of Hyperarousal)—and operationalized each criterion within the professional context by framing the traumatic stressor as “work with traumatized clients.” This theoretical integration provides both clinical diagnostic coherence and empirical measurability.

Validity

Extensive psychometric investigations across international research cohorts have established the multi-dimensional validity of the Secondary Traumatic Stress Scale.

Construct and Structural Validity

The structural validity of the STSS was initially evaluated by Bride et al. (2004) using a nationwide sample of 287 licensed clinical social workers. Both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) affirmed that the 17 items load onto three correlated latent factors corresponding precisely to the Intrusion, Avoidance, and Arousal dimensions. Goodness-of-fit indices demonstrated acceptable alignment with the hypothesized three-factor model (χ²/df ratios < 2.0; Comparative Fit Index [CFI] ≥ .90; Root Mean Square Error of Approximation [RMSEA] ≤ .06). Subsequent independent replications (e.g., Ting et al., 2005; Jacobs et al., 2010; Setti & Argentero, 2014) confirmed the structural integrity of this three-factor model across diverse professional cultures.

Convergent and Concurrent Validity

Convergent validity has been repeatedly demonstrated through significant, positive correlations with conceptually related psychometric measures. The STSS displays robust correlations with the Compassion Fatigue subscale of the Professional Quality of Life Scale (ProQOL; r values typically ranging between .65 and .78). Furthermore, STSS total and subscale scores correlate significantly with measures of psychological strain, generalized anxiety, and depressive symptoms, such as the General Health Questionnaire (GHQ-12; r = .52 to .64) and the Beck Depression Inventory (BDI-II; r = .48 to .59).

Discriminant Validity

Discriminant validity is supported by lower correlations between the STSS and general workplace burnout dimensions that do not involve trauma. Specifically, correlations between the STSS Intrusion subscale and the Depersonalization or Emotional Exhaustion subscales of the Maslach Burnout Inventory (MBI) remain moderate (typically r = .35 to .46), verifying that STS represents a distinct psychological construct separate from generic occupational exhaustion.

Predictive and Known-Groups Validity

Known-groups comparisons demonstrate that the STSS distinguishes between professionals with varying levels of direct trauma exposure. Caseworkers carrying high caseload percentages of sexually or physically abused clients score significantly higher across all three subscales compared to practitioners with low or negligible trauma exposure. Longitudinal and cross-sectional studies also demonstrate that elevated STSS scores predict occupational outcomes, including intent to leave the profession, elevated sick leave, and job-related functional impairment.

Reliability

The Secondary Traumatic Stress Scale demonstrates high internal consistency and measurement precision across multiple populations and languages:

• Internal Consistency (Cronbach’s Alpha): In the seminal instrument validation study by Bride et al. (2004; N = 287), the total scale achieved an overall Cronbach’s alpha of α = .93. The subscale reliability estimates were:
  • Intrusion Subscale: α = .80
  • Avoidance Subscale: α = .87
  • Arousal Subscale: α = .83
• Subsequent Independent Samples: Ting, Frey, Sanders, and Harrington (2005) examined hospital-based social workers, finding a total scale α of .94 (Intrusion α = .79, Avoidance α = .86, Arousal α = .85). In a psychometric validation of child welfare workers, Bride (2007) reported a total scale α of .94. International cross-cultural validations, such as Kazemi (2011) in an Iranian context, Setti and Argentero (2014) in Italy, and Molnar et al. (2017) in community legal aid attorneys, report total scale alpha coefficients ranging from .89 to .95.
• Item-Total Correlations: Corrected item-total correlations across validation studies range from .42 to .76, confirming that all 17 items contribute meaningfully to the overarching construct without redundancy.
• Test-Retest Stability: In studies evaluating temporal stability across 2- to 4-week intervals in stable work environments, test-retest reliability coefficients have ranged from r = .78 to r = .86, indicating high temporal stability while retaining sensitivity to longitudinal shifts in caseload intensity and intervention outcomes.

Factor Analysis

The underlying latent dimensions of the STSS have been rigorously examined using both exploratory (EFA) and confirmatory factor analytic (CFA) methods:

Original EFA and CFA (Bride et al., 2004)

During initial scale development, an exploratory factor analysis with oblique rotation on an initial pool of candidate items extracted three factors with eigenvalues exceeding 1.0, accounting for 60.1% of the total variance. Subsequent CFA evaluating the 17-item three-factor correlated model demonstrated acceptable data-to-model fit:

• χ² / df: 1.95 (below the traditional 2.0 threshold for good fit)
• CFI (Comparative Fit Index): .91
• NNFI / TLI (Non-Normed Fit Index): .89
• RMSEA (Root Mean Square Error of Approximation): .058 (90% CI [.047, .068])
• Standardized Factor Loadings: All 17 items loaded significantly (p < .001) onto their designated latent constructs, with loadings ranging from .54 to .82 for Intrusion, .58 to .80 for Avoidance, and .52 to .79 for Arousal.

Alternative Factor Models

Subsequent psychometric debates have investigated whether the STSS is best represented by a three-factor correlated model, a single-factor unidimensional model, or a second-order hierarchical model. Studies by Ting et al. (2005) and modern structural equation modeling by various international research teams (e.g., Jacobs et al., 2010) evaluated competing models:

• One-Factor Model: Positing that all items load on an undifferentiated STS factor; consistently demonstrates poor fit (χ²/df > 4.0; CFI < .80; RMSEA > .10).
• Three-Factor Correlated Model: Intrusion, Avoidance, and Arousal as separate, moderately-to-highly correlated latent traits (inter-factor correlations r = .68 to .84); demonstrates satisfactory to good fit across datasets.
• Second-Order Hierarchical Model: Positing that a single global higher-order Secondary Traumatic Stress factor accounts for the shared variance among the three first-order factors; demonstrates fit indices virtually identical to the three-factor correlated model. This provides empirical justification for calculating both subscale scores and an omnibus STSS composite score.

Instrument / Measurement Tool

• Test Name: Secondary Traumatic Stress Scale (STSS)
• Author(s): Brian E. Bride, Marmian R. Robinson, Bonnie L. Yegidis, and Charles R. Figley (2004)
• Construct Assessed: Secondary Traumatic Stress (Intrusion, Avoidance, Hyperarousal)
• Target Population: Human service professionals, clinicians, social workers, nurses, emergency first responders, forensic staff, and individuals indirectly exposed to trauma narratives through their professional duties
• Test Format: Standardized self-report questionnaire
• Item Count: 17 items
• Subscale Composition:
  • Intrusion Subscale: 5 items (Items 2, 3, 6, 10, 13)
  • Avoidance Subscale: 7 items (Items 1, 5, 7, 9, 12, 14, 17)
  • Arousal Subscale: 5 items (Items 4, 8, 11, 15, 16)
• Response Format: 5-point Likert-type scale:
  • 1 = Never
  • 2 = Rarely
  • 3 = Occasionally
  • 4 = Often
  • 5 = Very Often
• Timeframe / Recall Window: The preceding eight (8) days
• Scoring Algorithm:
  • Subscale scores are obtained by calculating the sum of the respective items: Intrusion (range: 5–25), Avoidance (range: 7–35), and Arousal (range: 5–25).
  • The Global STSS Total Score is computed by summing all 17 items (theoretical range: 17 to 85). No items are reverse-scored.
• Clinical Cutoff Guidelines (Bride, 2007):
  • Total Score < 28: Little to no secondary traumatic stress
  • Total Score 28–37: Mild secondary traumatic stress
  • Total Score 38–43: Moderate secondary traumatic stress
  • Total Score 44–48: High secondary traumatic stress
  • Total Score ≥ 49: Severe secondary traumatic stress
  • An individual may also be evaluated against DSM diagnostic thresholds if they endorse at least one Intrusion item, three Avoidance items, and two Arousal items at a frequency of 3 (Occasionally) or higher.

Permissions & Fee and Test Year

The Secondary Traumatic Stress Scale was formally published in 2004 in the peer-reviewed journal Research on Social Work Practice. The instrument was developed with public and academic support to advance traumatology research and occupational health.

Licensing and Usage: The scale is available for educational, research, and non-commercial clinical evaluation purposes without royalty fees, provided proper academic citation and attribution are extended to Dr. Brian E. Bride and co-authors. Commercial software distribution, digital medical record integration, or for-profit publication requires direct licensing authorization from the primary copyright holders and Sage Publications. Researchers interested in cross-cultural adaptations or standardized institutional implementations are encouraged to contact Dr. Brian E. Bride via Georgia State University.

References

• American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders (4th ed.). American Psychiatric Publishing. https://doi.org/10.1176/ajp.152.8.1228
• Bride, B. E. (2007). Prevalence of secondary traumatic stress among child welfare workers. Children and Youth Services Review, 29(1), 63–79. https://doi.org/10.1016/j.childyouth.2006.06.005
• Bride, B. E., Robinson, M. R., Yegidis, B., & Figley, C. R. (2004). Development and validation of the Secondary Traumatic Stress Scale. Research on Social Work Practice, 14(1), 27–35. https://doi.org/10.1177/1049731503254106
• Figley, C. R. (Ed.). (1995). Compassion fatigue: Coping with secondary traumatic stress disorder in those who treat the traumatized. Brunner/Mazel.
• Jacobs, G. A., Gray, B. L., Erickson, S. E., Gonzalez, E. D., & Quevillon, R. P. (2010). Disaster mental health innovations: The secondary traumatic stress scale. International Journal of Emergency Mental Health, 12(4), 225–232.
• Kazemi, A. S. (2011). Psychometric characteristics of STSS. Contemporary Psychology, 5(2), 638–640.
• McCann, I. L., & Pearlman, L. A. (1990). Vicarious traumatization: A framework for understanding the psychological effects of working with victims. Journal of Traumatic Stress, 3(1), 131–149. https://doi.org/10.1002/jts.2490030110
• Molnar, B. E., Sprang, G., Killian, K. D., Gottfried, R., Emery, V., & Bride, B. E. (2017). Advancing science and practice for vicarious traumatization: Where do we go from here? Traumatology, 23(2), 129–142. https://doi.org/10.1037/trm0000122
• Setti, I., & Argentero, P. (2014). The Italian version of the Secondary Traumatic Stress Scale: Psychometric properties and construct validity. TPM – Testing, Psychometrics, Methodology in Applied Psychology, 21(3), 311–325. https://doi.org/10.4473/TPM21.3.6
• Ting, L., Frey, J. J., Sanders, S., & Harrington, D. (2005). The Secondary Traumatic Stress Scale (STSS): Evaluating psychometric properties among hospital social workers. Journal of Human Behavior in the Social Environment, 11(3–4), 177–194. https://doi.org/10.1300/J137v11n03_09

13. Items of the Scale (Questionnaire)