Risk Assessment Scale for Pathological Scarring

1. Abstract

The Risk Assessment Scale for Pathological Scarring is a clinician-administered psychometric and clinical evaluation instrument designed to systematically quantify a patient’s susceptibility to abnormal cutaneous wound healing, specifically the formation of hypertrophic scars and keloids. Pathological scarring represents a profound dysregulation of normal wound healing characterized by persistent, localized chronic inflammation, exaggerated fibroblast proliferation, excessive synthesis and deposition of extracellular matrix (ECM) proteins, and an inability to achieve normal tissue remodeling. The scale was developed through a rigorous multi-phase psychometric process comprising systematic literature reviews, semi-structured expert interviews, and a two-round Delphi consensus technique involving wound care and plastic surgery specialists, followed by empirical validation in a clinical cohort.

Consisting of 12 clinician-rated items, the scale captures a multidimensional construct spanning systemic patient factors, localized wound parameters, and therapeutic interventions. Evaluated in a prospective validation sample of 409 patients presenting with surgical, burn, or traumatic wounds at West China Hospital of Sichuan University, China, the scale exhibited robust psychometric properties. Content validity was confirmed by an overall scale-level content validity index (S-CVI) of 0.82, with item-level content validity indices (I-CVI) ranging from 0.67 to 1.00. Exploratory factor analysis demonstrated a four-factor latent structure that accounted for 62.22% of the total cumulative variance, empirically expanding upon the baseline tripartite theoretical model. The instrument demonstrated satisfactory internal consistency, with an overall Cronbach’s alpha coefficient of 0.74, and substantial interrater reliability denoted by a Cohen’s kappa coefficient of 0.73. By standardizing the identification of physiological, mechanical, and clinical risks before overt fibrotic remodeling manifests, the scale empowers interdisciplinary medical teams to implement targeted, prophylactic interventions—such as dynamic mechanical offloading, silicone gel sheeting, and early anti-inflammatory pharmacotherapy—thereby mitigating long-term physical impairment, aesthetic deformity, and associated psychological trauma.

2. Keywords

pathological scarring, hypertrophic scars, keloids, risk assessment, psychometrics, clinical scale validation, wound healing, mechanobiology, chronic inflammation, West China Hospital

3. Authors

The Risk Assessment Scale for Pathological Scarring was conceptualized, developed, and clinically validated by an interdisciplinary research team from the Department of Burn and Plastic Surgery at West China Hospital, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China:

• Yanqiong Wang (Lead Investigator) — Department of Burn and Plastic Surgery, West China Hospital, Sichuan University, Chengdu, China. Email: [email protected].
• Ruiqi Liu — Department of Burn and Plastic Surgery, West China Hospital, Sichuan University, Chengdu, China.
• Zhihui Wu — Department of Burn and Plastic Surgery, West China Hospital, Sichuan University, Chengdu, China.
• Xuewen Xu — Department of Burn and Plastic Surgery, West China Hospital, Sichuan University, Chengdu, China.
• Lingxiao He — Department of Burn and Plastic Surgery, West China Hospital, Sichuan University, Chengdu, China.

The investigative team comprises clinical nurse specialists, reconstructive surgeons, and wound healing researchers specializing in complex burn reconstruction, aesthetic scar prevention, and cutaneous rehabilitation.

4. Purpose

Pathological scarring—predominantly manifesting as hypertrophic scars and keloids—constitutes a major global clinical challenge that straddles physiological disfigurement and profound psychological burden. Unlike normative, physiological scar maturation, which proceeds through self-limiting phases of hemostasis, acute inflammation, proliferation, and tissue remodeling, pathological scars display an unconstrained, persistent reparative trajectory. Patients suffering from hypertrophic scars and keloids frequently present with intractable physical symptoms, such as debilitating pruritus, severe neuropathic pain, loss of joint mobility due to contractures, and marked aesthetic deformities. Beyond biological dysfunction, pathological scarring is widely documented to precipitate severe psychological morbidities, including body dysmorphic concerns, social avoidance, clinically significant depression, generalized anxiety, and a diminished health-related quality of life.

Historically, clinical practice has been hampered by a reactive treatment paradigm. Frontline clinicians—encompassing trauma surgeons, dermatologists, burn specialists, and surgical nurses—typically initiate scar interventions only after abnormal, elevated, hyperemic fibrous tissue has already become clinically overt. Unfortunately, mature pathological scars are notoriously recalcitrant to therapeutic reversal; invasive modalities such as surgical excision carry recurrence rates exceeding 50% to 70% when implemented as monotherapy for keloids, and secondary therapies (including intralesional corticosteroid injections, cryotherapy, and radiotherapy) are often uncomfortable, expensive, and protracted. There has long been an acute clinical imperative to transition from reactive remediation toward early, proactive, and targeted prevention during the immediate perioperative and post-injury acute phases.

The primary purpose of the Risk Assessment Scale for Pathological Scarring is to bridge this translational gap by providing an evidence-based, multidimensional, clinician-administered screening instrument. The scale systematically operationalizes disparate, empirically verified risk determinants—ranging from intrinsic demographic and genomic susceptibilities to extrinsic biomechanical tension and clinical management variables—into a unified, objective scoring matrix. For practicing healthcare professionals, the instrument serves as an early triage tool administered during hospitalization or early outpatient follow-up to stratify patients into calibrated risk tiers (e.g., low, moderate, and high risk). Such stratification enables targeted resource allocation, permitting clinicians to prescribe aggressive prophylactic protocols—such as custom-fabricated pressure garments, early continuous silicone therapy, dynamic mechanomodulatory offloading taping, and prophylactic pulse dye laser treatments—exclusively to high-risk cohorts while sparing low-risk individuals unnecessary interventions and healthcare expenditures.

For clinical trialists and wound healing researchers, the scale establishes a standardized, reproducible metric that eliminates the subjective ambiguity of unstandardized clinical intuition. By providing a validated baseline index of scar vulnerability, the scale facilitates rigorous patient matching, robust stratification in randomized controlled trials (RCTs) evaluating novel anti-fibrotic pharmaceuticals or advanced wound dressings, and cross-study epidemiological meta-analyses.

5. Psychological Construct

The target construct measured by the instrument is Pathological Scarring Risk, conceptualized as a latent, multidimensional biopsychosocial and physiological liability. This construct reflects the cumulative, interactive probability that a cutaneous wound will diverge from normal physiological cicatrization and progress toward aberrant fibroproliferative tissue development. Within the scale’s operational framework, this liability is determined not by an isolated clinical parameter, but by the convergence of multiple distinct yet synergistic biological domains: Systemic Factors, Local Wound Factors, and Therapeutic/Clinical Management Factors. In the psychometric validation phase, empirical factor analysis further refined this construct into a robust four-factor latent model accounting for intrinsic biological vulnerabilities, local microenvironmental stresses, tissue trauma depth, and clinical management fidelity.

Systemic Factors (Host-Specific Susceptibility)

The systemic dimension captures patient-level biological, demographic, and genetic characteristics that establish the physiological threshold for excessive fibroproliferation. Empirical literature demonstrates that individual biological heterogeneity plays a decisive role in scar outcomes:

• Age and Endocrine Dynamics: Younger individuals, particularly adolescents and young adults, demonstrate a significantly higher incidence of pathological scarring compared to elderly populations. This heightened susceptibility is driven by elevated skin turgor, higher rates of baseline collagen synthesis, robust cutaneous vascularity, and endocrine fluctuations (such as elevated growth hormone and sex steroids).
• Genetic and Ethnic Predisposition: Familial clustering and genome-wide association studies (GWAS) have identified specific single-nucleotide polymorphisms (SNPs) in loci associated with inflammation and extracellular matrix remodeling (such as HLA alleles and TGF-β receptor pathways) that predispose certain individuals to keloidogenesis. Furthermore, populations with darker skin phototypes (Fitzpatrick scale IV–VI) demonstrate up to a fifteen-fold higher propensity for keloid development compared to lighter skin types.
• Systemic Immune and Metabolic Status: Comorbid systemic inflammatory states, nutritional deficiencies (e.g., hypoalbuminemia, trace mineral deficits), and metabolic dysregulation modulate systemic cytokine cascades, priming circulating monocytes and tissue-resident macrophages to maintain an unresolving, pro-fibrotic signaling environment.

Local Wound Factors (Microenvironmental and Biomechanical Stress)

The local wound dimension operationalizes the immediate biomechanical and physical milieu of the healing tissue, which exerts an immediate regulatory influence on fibroblast activation and matrix assembly:

• Anatomical Location and Mechanical Tension: Cutaneous areas exposed to high, continuous, or multidirectional resting tension and dynamic muscular movement—such as the anterior chest (presternal region), deltoid area, upper back, scapulae, and major articulating joints—exhibit the highest incidence of hypertrophic scarring and keloid formation. Mechanosensitive pathways translate elevated mechanical pull directly into sustained cellular activation.
• Wound Depth and Injury Mechanism: Wounds penetrating into the deep reticular dermis, such as deep partial-thickness burns, full-thickness crush injuries, or high-energy avulsions, destroy native dermal architecture and hair follicle stem cell niches, triggering repair via dense, disordered collagen deposition rather than functional regeneration.
• Local Infection and Prolonged Inflammation: The presence of localized microbial bioburden, foreign bodies, or hematomas prolongs the inflammatory phase of wound healing. Bacterial exotoxins and endotoxins continuously activate Toll-like receptors (TLRs), inducing sustained release of pro-inflammatory cytokines that prevent the transition to physiologic matrix remodeling.

Therapeutic Factors (Clinical Management and Iatrogenic Influences)

The therapeutic dimension evaluates the clinical practices, surgical techniques, and postoperative regimens that modulate the primary biological trajectory of the wound:

• Healing Time and Epithelialization Trajectory: The duration required to achieve complete re-epithelialization is one of the strongest independent clinical predictors of hypertrophic scarring. Wounds that heal within 14 days rarely develop pathological scars, whereas wounds that remain open beyond 21 days demonstrate an incidence of hypertrophic scar formation exceeding 70%.
• Surgical Technique and Incision Orientation: Surgical execution directly influences local tissue trauma. Inadequate debridement, excessive thermal injury from electrocautery, excessive tension on epidermal sutures, and failure to align surgical incisions along relaxed skin tension lines (Langer’s lines) dramatically amplify tissue injury and mechanical stress.
• Timeliness of Prophylactic Intervention: Early implementation of mechanical offloading, proper scar hydration, and protective barrier maintenance mitigates dermal stress during the initial, highly plastic phase of scar maturation.

6. Theoretical Framework

The Risk Assessment Scale for Pathological Scarring is grounded in contemporary wound healing biology, cutaneous mechanobiology, and biopsychosocial theories of chronic physical disfigurement. The conceptual architecture synthesizes three foundational paradigms: the Chronic Reticular Dermal Inflammation Hypothesis, the Mechanotransduction and Mechanobiology Paradigm, and the Biopsychosocial Vulnerability Model of visible health conditions.

The Chronic Reticular Dermal Inflammation Hypothesis

Advanced predominantly by Rei Ogawa and colleagues, this unifying biological framework posits that keloids and hypertrophic scars are not merely autonomous neoplasms or idiopathic fibroses, but rather clinical manifestations of chronic, non-resolving inflammation of the reticular dermis. While superficial papillary dermal injuries heal with minimal or imperceptible scarring, trauma extending into the deeper reticular dermis injures dense microvascular networks and structural collagen scaffolding.

Under physiological conditions, the inflammatory phase is acute and self-limiting: neutrophils infiltrate the wound bed, followed by macrophages that transition sequentially from a pro-inflammatory (M1) to an anti-inflammatory, pro-resolving (M2) phenotype. In pathological scarring, genetic susceptibilities and microenvironmental irritants disrupt this phenotypical transition. Macrophages remain arrested in a chronic secretory state, continuously synthesizing elevated concentrations of key pro-fibrotic cytokines, most notably Transforming Growth Factor-Beta 1 and 2 (TGF-β1, TGF-β2), Platelet-Derived Growth Factor (PDGF), and Interleukin-6 (IL-6). These signaling molecules stimulate dermal fibroblasts to transdifferentiate into contractile myofibroblasts expressing alpha-smooth muscle actin (α-SMA). The myofibroblasts synthesize massive quantities of Type I and Type III collagen while downregulating Matrix Metalloproteinases (MMPs) and upregulating Tissue Inhibitors of Metalloproteinases (TIMPs), permanently tilting the equilibrium toward unabated collagen accumulation.

Mechanotransduction and Mechanobiology Paradigm

The scale integrates the fundamental principles of mechanobiology, which explain how physical forces are converted into biochemical cellular responses. The skin is continuously subjected to dynamic resting skin tension and cyclic muscular movement. When a surgical or traumatic wound breaches the dermis, normal force vectors are interrupted, concentrating physical stress at the wound margins.

At the cellular level, mechanical strain is sensed by cell-surface integrins, stretch-activated ion channels (e.g., Piezo1, TRPV4), and focal adhesion complexes. This mechanical stimulation triggers intracellular signaling cascades, principally the Rho/Rho-associated protein kinase (ROCK) and FAK-ERK pathways, leading to the nuclear translocation of YAP/TAZ (Yes-associated protein/transcriptional co-activator with PDZ-binding motif). Nuclear YAP/TAZ directly promotes the transcription of pro-fibrotic genes, perpetuating collagen synthesis and cell survival. Consequently, anatomical regions subjected to high mechanical tension experience continuous mechanotransductive signaling, sustaining chronic inflammation and preventing physiological scar maturation.

Biopsychosocial Integration in Cutaneous Trauma

From an applied psychometric perspective, the scale operationalizes physiological vulnerability within a broader biopsychosocial paradigm. A patient’s recovery from acute cutaneous trauma does not occur within a biological vacuum; systemic physiological vulnerability interacts directly with behavioral adherence to wound protocols, pain responses, psychological stress, and long-term coping mechanisms. Chronic psychoneuroimmunological stress is well-documented to elevate systemic circulating cortisol and pro-inflammatory cytokines, impairing primary barrier restoration and extending epithelialization times beyond critical thresholds. By identifying patients early, the scale serves as a preventative bridge, curtailing the biological cascade before it culminates in physical disfigurement and subsequent severe psychological trauma.

7. Validity

The empirical validation of the Risk Assessment Scale for Pathological Scarring adhered to rigorous psychometric protocols governing clinical measurement tools, encompassing content validity, construct validity, and preliminary clinical predictive assessments.

Content Validity

The preliminary item pool was generated through a two-tiered qualitative phase: a comprehensive systematic review of peer-reviewed clinical literature on hypertrophic scars and keloids, followed by in-depth semi-structured interviews with plastic surgeons, dermatologists, and wound care specialists. To establish robust content validity, the draft instrument was subjected to a two-round Delphi expert consultation process.

The Delphi panel consisted of recognized clinical specialists in burn surgery, aesthetic and reconstructive plastic surgery, and wound management nursing. Panelists evaluated each item on its relevance, clarity, and necessity using a standard ordinal rating scale. Item-level Content Validity Indices (I-CVI) ranged from 0.67 to 1.00 across the evaluated items. Items that failed to meet established consensus thresholds (I-CVI < 0.78) were systematically reviewed, modified, or eliminated. The overall Scale-Level Content Validity Index averaging method (S-CVI/Ave) yielded a coefficient of 0.82, exceeding the widely accepted psychometric threshold of 0.80. This confirmed that the 12 retained items comprehensively and accurately captured the target construct of pathological scarring risk without unnecessary redundancy.

Construct and Structural Validity

Construct validity was evaluated using a prospective cohort of 409 wound patients admitted to the Department of Burn and Plastic Surgery at West China Hospital, Sichuan University, between November 2021 and April 2022. Exploratory factor analysis demonstrated that the empirical covariance among the 12 items was well-represented by a clean four-factor model. The data satisfied standard prerequisite assumptions for factorability, demonstrating high sampling adequacy and meaningful inter-item correlation structures.

All 12 items demonstrated substantial factor loadings onto their primary latent constructs (predominantly exceeding 0.40 to 0.50), with minimal cross-loadings. The extracted factors aligned coherently with the underlying theoretical framework, demonstrating strong factorial validity by confirming that the scale measured its hypothesized latent dimensions rather than random measurement noise.

Predictive and Convergent Validity

Preliminary predictive performance was evaluated by monitoring patient cohorts through acute wound healing into intermediate scar maturation. Scores obtained from the 12-item scale correlated significantly with subsequent clinical scar manifestations, differentiating patients who healed with flat, pale, mature cicatrices from those who developed elevated, hyperemic, symptomatic hypertrophic tissue. Furthermore, high-risk scores correlated with objective wound parameters, including prolonged healing durations (>21 days) and heightened local inflammatory scores, demonstrating solid concurrent and criterion-related validity.

8. Reliability

The reliability of the Risk Assessment Scale for Pathological Scarring was examined across multiple dimensions of psychometric stability, specifically evaluating internal consistency and interrater reproducibility.

Internal Consistency

Internal consistency reflects the degree to which items within an instrument measure the same general construct and yield mutually supportive scores. In the primary clinical validation sample of 409 patients, the overall instrument demonstrated a Cronbach’s alpha coefficient of 0.74.

In psychometric instrument development—particularly for multidimensional risk screening tools comprising diverse biological, mechanical, and environmental indicators—a Cronbach’s alpha between 0.70 and 0.80 represents an optimal balance. An alpha of 0.74 indicates sufficient inter-item correlation and conceptual coherence without the excessive item redundancy commonly observed in scales with alpha values exceeding 0.90 (which often indicate overly narrow or duplicated items). Each of the underlying subscales maintained acceptable internal consistency, confirming that the tool reliably reflects unified pathological scarring vulnerability.

Interrater Reliability

Because the Risk Assessment Scale for Pathological Scarring is a clinician-administered instrument that requires healthcare providers to evaluate clinical wound characteristics, anatomical tension, and patient history, assessing interrater concordance was critical to ensure clinical utility across diverse examiners. A subset of patient wounds was independently evaluated by multiple trained clinical raters (encompassing surgical residents and specialist wound care nurses) under identical clinical conditions.

Interrater agreement was statistically quantified using Cohen’s kappa (κ), yielding a coefficient of 0.73. In clinical psychometrics, a Kappa value between 0.61 and 0.80 denotes substantial agreement beyond chance. This high level of concordance demonstrates that the operational definitions and objective scoring criteria established for each of the 12 items are clear, robust, and minimally susceptible to individual examiner subjectivity, ensuring stable risk assessment across varying hospital shifts and practitioner backgrounds.

9. Factor Analysis

To identify the underlying latent dimensions of the 12-item scale, the researchers conducted an Exploratory Factor Analysis (EFA) on data collected from the 409 surgical and trauma patients. Prior to extraction, the correlation matrix was assessed to ensure suitability for factor analysis:

• The Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy confirmed high data suitability for factor extraction.
• Bartlett’s Test of Sphericity achieved statistical significance (p < 0.001), rejecting the null hypothesis that the correlation matrix was an identity matrix and verifying substantial inter-item correlations.

Factor Extraction and Variance Explained

Principal component analysis combined with orthogonal (Varimax) rotation was utilized to identify the latent factor structure. Based on the Kaiser criterion (retaining eigenvalues > 1.0) and visual inspection of the scree plot, the empirical analysis extracted four common factors. Collectively, these four latent factors accounted for 62.22% of the total variance, exceeding the standard 60% cumulative variance threshold generally recommended in clinical psychometric validation.

Factorial Structure Interpretation

While the initial theoretical framework conceptualized scar risk across three broad domains (Systemic, Local, and Therapeutic), the empirical emergence of four statistical factors reflects a more nuanced, clinically granular architecture:

• Factor 1 (Local Biomechanical and Anatomical Strain): Captures items indexing the anatomical distribution of the wound, baseline skin tension, dynamic joint movement, and surgical line orientation. This factor explained the largest proportion of unique variance, aligning with modern mechanobiological theories that emphasize physical strain as the primary driver of persistent fibroblast activation.
• Factor 2 (Wound Bed Environment and Inflammatory Status): Encompasses items measuring localized microenvironmental parameters, including bacterial contamination, presence of infection, foreign body reaction, and wound exudate levels, reflecting the persistent inflammation paradigm.
• Factor 3 (Injury Severity and Tissue Depth): Comprises items reflecting the anatomical depth of cutaneous disruption (reticular dermis vs. superficial dermis), the mechanism of trauma (burns, avulsions, sharp incisional wounds), and the time to complete re-epithelialization.
• Factor 4 (Host Intrinsic and Systemic Susceptibility): Encompasses systemic patient-level characteristics, including age, personal or familial history of keloid/hypertrophic scar formation, and underlying metabolic or genetic vulnerabilities.

Each of the 12 items demonstrated robust factor loadings (> 0.45) on its designated latent factor, with minimal cross-loadings onto secondary factors, confirming strong structural validity and construct distinctiveness.

10. Instrument / Measurement Tool

The Risk Assessment Scale for Pathological Scarring is a standardized clinical assessment tool designed for direct administration by trained medical personnel. Its structural and administrative specifications are outlined below:

• Test Type: Clinician-rated risk assessment and screening instrument.
• Format: 12 structured clinical items evaluating physiological, mechanical, anatomical, and management parameters.
• Administration Setting: Inpatient burn and plastic surgery units, trauma centers, outpatient dermatology clinics, and surgical post-acute care units.
• Target Population: Adult and pediatric patients with open cutaneous wounds, acute surgical incisions, traumatic lacerations, or burn injuries.
• Language: Originally developed and validated in Chinese; professional English translations utilized in international academic reporting.
• Administration Time: Approximately 5 to 10 minutes per patient, integrating clinical chart review with direct physical wound inspection.
• Rater Qualifications: Registered nurses specializing in wound care, plastic and reconstructive surgeons, dermatologists, and surgical residents trained in standard wound bed assessment.
• Scoring Format: Each item is rated on an objective ordinal scale corresponding to empirically weighted risk strata. Summed composite scores yield a total continuous risk score.
• Risk Stratification: Total scores correspond to validated cut-off tiers categorized into Low Risk, Moderate Risk, and High Risk for pathological scar development, providing direct guidance for clinical prophylaxis pathways.

11. Permissions & Fee and Test Year

The Risk Assessment Scale for Pathological Scarring was developed and clinically validated between 2021 and 2022, with formal peer-reviewed academic publication in 2023 in the International Wound Journal.

The instrument is the intellectual property of the original research team at West China Hospital, Sichuan University, and the publishing journal (John Wiley & Sons Ltd). While the theoretical framework, psychometric properties, and structural scoring methodologies are fully detailed in published literature, the complete, official clinician scoring sheet and standardized implementation guide remain proprietary. The instrument is generally made accessible free of charge for non-commercial academic research, institutional clinical audits, and public health investigations upon formal request to the corresponding author (Yanqiong Wang, [email protected]). Commercial utilization, incorporation into proprietary digital electronic health record (EHR) modules, or unauthorized redistribution for financial gain requires formal written licensing agreements and copyright permissions from the copyright holders.

12. References

The following peer-reviewed literature provides foundational theoretical, methodological, and psychometric grounding for the development and validation of the Risk Assessment Scale for Pathological Scarring:

• Butzelaar, L., Ulrich, M. M., Mink van der Molen, A. B., Niessen, F. B., & Beelen, R. H. (2016). Currently known risk factors for hypertrophic skin scarring: A review. Journal of Plastic, Reconstructive & Aesthetic Surgery, 69(2), 163–169. https://doi.org/10.1016/j.bjps.2015.11.015
• Deflorin, C., Hohenauer, E., Stoop, R., van Daele, U., Clijsen, R., & Taeymans, J. (2020). Physical management of scar tissue: A systematic review and meta-analysis. The Journal of Alternative and Complementary Medicine, 26(10), 854–865. https://doi.org/10.1089/acm.2020.0109
• Elsaie, M. L. (2021). Update on management of keloid and hypertrophic scars: A systemic review. Journal of Cosmetic Dermatology, 20(9), 2729–2738. https://doi.org/10.1111/jocd.14310
• Friedstat, J. S., & Hultman, C. S. (2014). Hypertrophic burn scar management. Annals of Plastic Surgery, 72(6), S198–S201. https://doi.org/10.1097/SAP.0000000000000103
• Frykberg, R. G., & Banks, J. (2015). Challenges in the treatment of chronic wounds. Advances in Wound Care, 4(9), 560–582. https://doi.org/10.1089/wound.2015.0635
• Mahdavian Delavary, B., van der Veer, W. M., Ferreira, J. A., & Niessen, F. B. (2012). Formation of hypertrophic scars: Evolution and susceptibility. Journal of Plastic Surgery and Hand Surgery, 46(2), 95–101. https://doi.org/10.3109/2000656X.2012.669184
• Monstrey, S., Middelkoop, E., Vranckx, J. J., Bassetto, F., Ziegler, U. E., Meaume, S., & Téot, L. (2014). Updated scar management practical guidelines: Non-invasive and invasive measures. Journal of Plastic, Reconstructive & Aesthetic Surgery, 67(8), 1017–1025. https://doi.org/10.1016/j.bjps.2014.04.011
• Nakashima, M., Chung, S., Takahashi, A., Kamatani, N., Kawaguchi, T., Tsunoda, T., Hosono, N., Kubo, M., Nakamura, Y., & Zembutsu, H. (2010). A genome-wide association study identifies four susceptibility loci for keloid in the Japanese population. Nature Genetics, 42(9), 768–771. https://doi.org/10.1038/ng.645
• Ogawa, R. (2017). Keloid and hypertrophic scars are the result of chronic inflammation in the reticular dermis. International Journal of Molecular Sciences, 18(3), 606. https://doi.org/10.3390/ijms18030606
• Ogawa, R., Watanabe, A., Than Naing, B., Sasaki, M., Fujita, A., Akaishi, S., Hyakusoku, H., & Shimada, T. (2014). Associations between keloid severity and single-nucleotide polymorphisms: Importance of rs8032158 as a biomarker of keloid severity. Journal of Investigative Dermatology, 134(7), 2041–2043. https://doi.org/10.1038/jid.2014.71
• Wang, Y., Liu, R., Wu, Z., Xu, X., & He, L. (2023). Risk assessment scale for pathological scarring. International Wound Journal, 20(9), 3737–3745. https://doi.org/10.1111/iwj.14241
• Wang, Z., Zhao, W., Cao, Y., Liu, Y., Sun, Q., Shi, P., & Li, Z. (2020). The roles of inflammation in keloid and hypertrophic scars. Frontiers in Immunology, 11, 603187. https://doi.org/10.3389/fimmu.2020.603187
• Yang, S., Luo, Y., & Luo, C. (2021). Network meta-analysis of different clinical commonly used drugs for the treatment of hypertrophic scar and keloid. Frontiers in Medicine, 8, 691628. https://doi.org/10.3389/fmed.2021.691628

13. Items of the Scale