Self-Management Efficacy Questionnaire among Patients with Psoriasis

Abstract

The Self-Management Efficacy Questionnaire among Patients with Psoriasis (SMEQ-PSO) is a specialized, psychometrically validated patient-reported outcome measure designed to evaluate domain-specific self-efficacy in individuals diagnosed with psoriasis. Characterized as a chronic, systemic immune-mediated inflammatory disorder, psoriasis necessitates multifaceted, lifelong behavioral self-regulation, spanning topical regimens, systemic therapeutics, lifestyle modifications, and psychosocial coping. Developed and validated by Sun, Zhang, Yang, and Wang (2023) at China Medical University and Dalian Medical University, the SMEQ-PSO addresses a critical measurement void in dermatological health psychology by capturing the complex cognitive architecture underpinning patient disease self-management. The instrument comprises 28 items mapped across five distinct empirical dimensions: (1) Self-efficacy of Psychosocial Adaptation, (2) Self-efficacy of Daily Life Management, (3) Self-efficacy of Skin Management, (4) Self-efficacy of Disease Knowledge Management, and (5) Self-efficacy of Disease Treatment Management. Responses are gathered on a 5-point Likert scale ranging from 1 ("completely unconfident") to 5 ("absolutely completely confident"), generating dimension-specific subscale totals and an overarching composite score where higher values reflect superior self-management confidence.

Psychometric evaluation was executed using a rigorous dual-phase methodology with 440 adult psoriasis patients recruited from tertiary medical centers in Shenyang, China. The SMEQ-PSO demonstrated outstanding internal consistency reliability, with an overall Cronbach’s alpha of α = 0.930 and a split-half reliability coefficient of 0.952. Temporal stability evaluated via a two-week test-retest interval yielded an intraclass correlation coefficient of r = 0.768. Structural validity, assessed via exploratory factor analysis (EFA), established a five-factor structure accounting for 62.039% of the total cumulative variance, subsequently corroborated through confirmatory factor analysis (CFA) demonstrating robust goodness-of-fit indices. Content validity was confirmed through an expert panel yielding a Scale-Content Validity Index (S-CVI) of 0.976, while criterion-related validity was demonstrated via positive convergent correlation with the General Self-Efficacy Scale (GSES). By offering an empirically grounded, disease-specific diagnostic metric, the SMEQ-PSO equips clinical dermatologists, behavioral medicine specialists, and health psychology researchers to identify nuanced behavioral vulnerabilities, formulate personalized psychoeducational interventions, and optimize long-term clinical trajectories in chronic dermatological care.

Keywords

Psoriasis, Self-Management Efficacy Questionnaire, SMEQ-PSO, Self-Efficacy, Psychometrics, Chronic Disease Management, Health Psychology, Patient-Reported Outcome Measures, Factor Analysis, Behavioral Medicine

Authors

The development and psychometric validation of the Self-Management Efficacy Questionnaire among Patients with Psoriasis were conducted by a collaborative research team specializing in public healthcare, clinical dermatology, cardiovascular medicine, and nursing science in Liaoning Province, China:

• Yuanhui Sun — Department of Public Service, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, People’s Republic of China.
• Xiujie Zhang — Department of Cardiology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning Province, People’s Republic of China.
• Zhen Yang — Department of Public Service, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, People’s Republic of China.
• Aiping Wang (Corresponding Author) — Department of Public Service, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, People’s Republic of China. Email: [email protected].

Purpose

Psoriasis is a chronic, non-communicable, inflammatory dermatosis associated with substantial morbidity, disfigurement, psychological distress, and elevated systemic comorbidities, including psoriatic arthritis, cardiovascular disease, metabolic syndrome, and clinical depression. The therapeutic management of psoriasis is notoriously complex, requiring individuals to sustain persistent, demanding self-care routines over decades. Despite the emergence of targeted biologic therapies and advanced systemic agents, a substantial proportion of patients experience suboptimal therapeutic outcomes directly attributable to low adherence, lifestyle mismanagement, and inability to navigate disease-related psychological distress. In chronic disease literature, therapeutic outcomes depend not merely on clinical interventions, but centrally upon the patient’s personal capacity to execute autonomous disease self-management.

Historically, psychological evaluations within dermatological cohorts have predominantly utilized generalized self-efficacy instruments, such as the General Self-Efficacy Scale (GSES) developed by Ralf Schwarzer and Matthias Jerusalem, or generic chronic disease self-management metrics. While these instruments provide an overarching appraisal of perceived personal agency, they systematically fail to detect the granular, condition-specific behavioral challenges inherent to dermatological pathology. For example, generic scales cannot evaluate a patient’s confidence in applying complex topical regimens, managing localized pruritus without causing Koebner phenomenon-induced flare-ups, handling public social stigma provoked by visible cutaneous plaques, or modifying dietary and lifestyle triggers specific to systemic psoriatic inflammation.

The development of the SMEQ-PSO was undertaken to resolve this methodological disconnect. The scale serves several primary purposes across clinical and research paradigms:

• Granular Clinical Assessment: It enables healthcare providers, dermatologists, and nurse practitioners to systematically evaluate baseline levels of self-efficacy across distinct operational domains rather than relying on an ambiguous composite self-efficacy rating.
• Targeted Psychoeducational Intervention: By delineating five independent subscales, the instrument pinpoints specific behavioral deficits. For example, a patient exhibiting robust confidence in medical treatment adherence may simultaneously demonstrate profound self-doubt regarding psychosocial adaptation or daily lifestyle regulation, allowing clinicians to tailor supportive behavioral therapies specifically to these deficient domains.
• Evaluation of Interventional Efficacy: In translational research and randomized controlled trials, the SMEQ-PSO provides a sensitive, disease-specific endpoint to measure the cognitive and behavioral impacts of digital health applications, therapeutic patient education (TPE) programs, and psychological interventions such as Cognitive Behavioral Therapy (CBT) or Acceptance and Commitment Therapy (ACT).
• Mitigation of Recurrence and Flares: Enhanced self-management efficacy correlates empirically with reduced flare frequency, prompt identification of secondary infections or joint symptoms, and improved overall health-related quality of life.

Psychological Construct

The SMEQ-PSO operationalizes the overarching psychological construct of disease-specific self-management efficacy within the context of psoriasis. Self-management efficacy refers to an individual’s cognitive appraisal of, and subjective confidence in, their behavioral capability to execute the requisite self-care actions, problem-solving strategies, emotional coping mechanisms, and treatment protocols needed to manage a chronic illness. The construct does not measure actual performed behaviors (which represents adherence or compliance per se), but rather the internal self-belief and cognitive conviction that one can mobilize the motivation, cognitive resources, and courses of action necessary to satisfy situational demands.

Recognizing the multidimensionality of chronic inflammatory illness, the SMEQ-PSO conceptualizes psoriasis self-management efficacy as an organized, five-dimensional latent construct:

1. Self-Efficacy of Psychosocial Adaptation

This dimension quantifies the patient’s confidence in processing, buffering, and regulating the psychosocial and emotional sequelae provoked by living with a visible, stigmatizing skin condition. Psoriasis frequently imposes a profound burden of felt stigma, social anxiety, body dissatisfaction, and perceived social alienation. This subscale measures confidence in:

• Regulating internal emotional turmoil, including embarrassment, frustration, depressive moods, and anxiety regarding disease prognosis.
• Engaging comfortably in social, occupational, and interpersonal environments without resorting to maladaptive social withdrawal or experiential avoidance.
• Coping with negative public reactions, stares, or misconceptions regarding contagiousness.
• Mobilizing social support networks and openly communicating with family and friends regarding disease impacts.

2. Self-Efficacy of Daily Life Management

Extrinsic and environmental exposures play an established role in triggering or exacerbating psoriatic hyperproliferation and systemic inflammation. The Daily Life Management dimension evaluates patient confidence in modifying and maintaining health-promoting routines, specifically assessing confidence in:

• Adopting and sustaining an anti-inflammatory nutritional pattern while abstaining from known pro-inflammatory triggers such as alcohol and tobacco.
• Maintaining regular, structured physical activity while appropriately managing skin friction, sweat-induced irritation, and psoriatic joint discomfort.
• Establishing consistent sleep hygiene and practicing active stress-reduction techniques (e.g., mindfulness, relaxation exercises), given that psychogenic stress is one of the most potent triggers for hypothalamic-pituitary-adrenal axis activation and cutaneous flare-ups.

3. Self-Efficacy of Skin Management

Dermatological conditions mandate continuous, physically demanding cutaneous maintenance. This subscale assesses the patient’s perceived self-efficacy in executing technical, day-to-day dermatological skin care routines, including:

• Implementing rigorous, time-consuming skin hydration routines, such as applying thick emollients and barrier-repairing formulations across extensive body surface areas.
• Refraining from scratching, rubbing, or peeling scales to prevent the Koebner phenomenon (isomorphic response) and secondary bacterial infections.
• Regulating bathing parameters, including water temperature, mild non-soap cleansers, and safe post-bath drying techniques to preserve cutaneous stratum corneum barrier integrity.
• Accurately monitoring cutaneous status, distinguishing normal plaque shedding from signs of acute flare-ups, infection, or pustular transition.

4. Self-Efficacy of Disease Knowledge Management

Given the rapidly evolving therapeutic landscape and prevalent medical misinformation regarding autoimmune disorders, health literacy is essential to disease management. This dimension measures the patient’s perceived agency and competence in acquiring, analyzing, and operationalizing medical knowledge regarding psoriasis, encompassing:

• Proactively seeking verified, scientific information from credible medical providers and clinical literature rather than commercialized or unverified remedies.
• Synthesizing and retaining essential knowledge regarding systemic inflammation, genetic etiology, non-contagiousness, and common triggers.
• Translating conceptual health literacy into actionable daily decisions and maintaining realistic expectations regarding treatment timelines, relapses, and remissions.

5. Self-Efficacy of Disease Treatment Management

This subscale evaluates the patient’s perceived self-efficacy regarding long-term, rigorous adherence to prescribed pharmacotherapy and proactive collaboration with medical specialists. It encompasses confidence in:

• Strictly adhering to complex topical schedules, oral systemic medications, or biologic subcutaneous self-injections according to clinical protocols.
• Managing potential medication side effects, recognizing adverse drug reactions, and coordinating timely clinical follow-ups and routine laboratory safety monitoring (e.g., liver function panels, complete blood counts).
• Communicating effectively with dermatologists, expressing personal preferences, asking questions during consultations, and participating in shared clinical decision-making.

Theoretical Framework

The SMEQ-PSO is theoretically anchored in Albert Bandura’s seminal Social Cognitive Theory (1977, 1986, 1997) and specifically operationalizes the construct of perceived self-efficacy within Bandura’s triadic reciprocal causation model. Bandura defined perceived self-efficacy as "beliefs in one’s capabilities to organize and execute the courses of action required to produce given attainments." In social cognitive paradigms, human functioning is not merely dictated by autonomous agency or external environmental pressures; rather, it is the product of continuous reciprocal interaction between cognitive/biological events, behavioral patterns, and environmental influences.

Central to Bandura’s theory is the postulate that self-efficacy is fundamentally domain-specific rather than a universal, static personality trait. While an individual may exhibit superior self-efficacy within academic or professional domains, they may concurrently experience acute low efficacy when confronting chronic health self-regulation. In chronic illness, an individual’s perceived self-efficacy determines:

• Choice of Behaviors: Whether a patient chooses to engage in proactive health behaviors (e.g., daily emollient application, dietary vigilance) or defaults to avoidance behaviors.
• Effort Expenditure and Persistence: How much effort individuals invest and how long they persevere when facing therapeutic setbacks, such as unexpected disease relapses or drug resistance.
• Thought Patterns and Emotional Reactions: Whether cognitive appraisals focus on coping strategies and self-mastery or fixate on catastrophic self-doubt, somatic distress, and perceived helplessness.

According to Bandura, perceived self-efficacy is continuously informed and calibrated by four primary informational sources:

1. Enactive Mastery Experiences: The most potent source of efficacy beliefs. Authentic behavioral successes build robust self-efficacy, while recurring behavioral failures undermine it. In psoriasis, experiencing effective clearing through meticulous adherence reinforces a patient’s confidence in their management capabilities.
2. Vicarious Experiences: Observing social peers successfully navigate similar health challenges. In psoriasis peer groups or therapeutic workshops, witnessing fellow patients maintain clear skin through structured lifestyle regimens enhances the observer’s belief in their own capability.
3. Verbal / Social Persuasion: Encouragement, psychoeducation, and clinical validation provided by healthcare practitioners, family members, and support networks.
4. Physiological and Affective States: How individuals interpret their somatic stress reactions, itch intensity, and emotional arousal. High autonomic arousal, somatic pain, and visible flaring are often cognitively misinterpreted by low-efficacy patients as proof of unavoidable failure, exacerbating depressive passivity.

The SMEQ-PSO also synthesizes principles from the Chronic Disease Self-Management Framework developed by Kate Lorig and colleagues at Stanford University. Lorig posited that living with chronic illness necessitates the mastery of three core tasks: (1) medical management of the condition, (2) role management (maintaining social, familial, and occupational roles), and (3) emotional management (coping with anger, fear, and depression). The five dimensions of the SMEQ-PSO align with this conceptual architecture: Treatment and Skin Management capture medical management; Psychosocial Adaptation addresses emotional and role management; and Daily Life and Knowledge Management integrate behavioral and cognitive self-regulation.

Validity

The developers executed an empirical validation process to confirm the psychometric properties of the SMEQ-PSO, following standardized methodological guidelines for patient-reported outcome development.

Content and Face Validity

The initial pool of items was formulated following a literature review of psoriasis management guidelines, social cognitive theory literature, and semi-structured qualitative interviews with adult psoriasis patients and dermatologists. To evaluate content relevance, clarity, and theoretical representativeness, a two-round Delphi consultation was conducted with an expert multidisciplinary panel consisting of clinical dermatologists, psychological methodologists, and nursing scientists. Item-level and scale-level Content Validity Indices were calculated:

• The Scale-Content Validity Index (S-CVI) achieved an exceptional coefficient of 0.976, surpassing the widely accepted psychometric threshold of 0.80 or 0.90 recommended for newly developed instruments.
• Individual Item-Content Validity Indices (I-CVI) exceeded 0.85 across all retained items, confirming that each statement captured critical operational facets of psoriasis self-management without redundancy or construct irrelevance.

Construct, Convergent, and Discriminant Validity

Construct validity was evaluated through correlation matrices, structural factor modeling, and convergent/discriminant indices:

• Criterion-Related Convergent Validity: Convergent validity was established by administering the SMEQ-PSO concurrently with the validated Chinese version of the General Self-Efficacy Scale (GSES). The analysis confirmed statistically significant positive bivariate correlations between the total SMEQ-PSO score, its subscales, and the GSES. This indicates that while the SMEQ-PSO is theoretically rooted in broader self-efficacy constructs, it captures unique variance specific to dermatological management.
• Convergent Validity via Latent Constructs: In structural equation modeling, composite reliability (CR) values for all five latent dimensions surpassed the 0.70 benchmark. The Average Variance Extracted (AVE) values confirmed that the items within each subscale accounted for a substantial portion of latent variance.
• Discriminant Validity: Evaluated through Fornell-Larcker criteria and inter-factor correlation analysis, the square root of the AVE for each latent factor exceeded the bivariate correlation coefficients between that factor and all other dimensions, demonstrating that the five dimensions measure distinct behavioral constructs rather than overlapping concepts.

Reliability

The SMEQ-PSO was subjected to comprehensive classical test theory (CTT) reliability evaluations across sample subsets to confirm internal consistency, item homogeneity, and temporal stability:

Internal Consistency Reliability

Internal consistency evaluates the degree to which items within an instrument or subscale correlate with each other and measure the same underlying construct:

• Overall Scale Consistency: For the total 28-item scale, the global Cronbach’s alpha reached α = 0.930. This indicates high internal consistency reliability, placing the instrument well above the recommended 0.80 standard for clinical screening and research applications.
• Subscale Consistency: Individual Cronbach’s alpha values across the five extracted subscales ranged from 0.81 to 0.91, demonstrating that each independent subscale is internally consistent.
• Split-Half Reliability: Item split-half reliability calculated via the Spearman-Brown formula yielded an index of 0.952, confirming that both halves of the questionnaire assess equivalent domains of the latent construct without systematic item order fatigue or bias.

Temporal Stability (Test-Retest Reliability)

To establish that the SMEQ-PSO measures a relatively stable psychological state rather than transient mood fluctuations, test-retest reliability was conducted:

• A representative subsample of stable, non-acute psoriasis outpatients completed the SMEQ-PSO a second time following a standardized two-week interval during which no therapeutic or psychoeducational modifications were made.
• The two-week test-retest reliability intraclass correlation coefficient was r = 0.768 (p < 0.001). This confirms that the instrument demonstrates adequate temporal stability over short intervals while retaining sensitivity to longitudinal changes induced by structured psychological or clinical interventions.

Factor Analysis

The structural integrity and latent dimensionality of the SMEQ-PSO were examined using a two-stage factor analytic framework, employing Exploratory Factor Analysis (EFA) followed by Confirmatory Factor Analysis (CFA) across split sample halves of the 440 adult psoriasis participants.

Exploratory Factor Analysis (EFA)

Prior to extraction, sampling adequacy and data factorability were confirmed:

• The Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy yielded an index exceeding 0.90, well above the standard 0.60 threshold.
• Bartlett’s Test of Sphericity reached statistical significance (χ² test, p < 0.001), indicating the correlation matrix was factorable.
• Principal Component Analysis followed by oblique (Promax) rotation was deployed to reflect theoretical intercorrelations among self-management domains.
• Based on the Kaiser criterion (eigenvalues > 1.0) and visual inspection of the scree plot inflection point, a clean five-factor solution was extracted.
• The five extracted factors accounted for 62.039% of the cumulative total variance. Each of the 28 items demonstrated strong factor loadings (> 0.45, with the majority exceeding 0.60) onto their primary theoretical factor, with no cross-loadings > 0.35.

Confirmatory Factor Analysis (CFA)

To cross-validate the structural architecture derived from EFA, Confirmatory Factor Analysis was conducted using Maximum Likelihood estimation within a structural equation modeling environment:

• The hypothesized first-order five-factor model demonstrated an acceptable fit with the observed data:
• Chi-Square to Degrees of Freedom Ratio (χ²/df): Fell within the acceptable standard (< 3.0).
• Root Mean Square Error of Approximation (RMSEA): Exhibited an estimate < 0.08, indicating an acceptable approximation error in the population.
• Comparative Fit Index (CFI) and Tucker-Lewis Index (TLI): Both incremental indices exceeded the 0.90 benchmark, confirming robust fit against baseline null models.
• Standardized Root Mean Square Residual (SRMR): Demonstrated values below 0.06.

The CFA results confirmed that the 28 items load onto five distinct first-order latent constructs that converge into a unified higher-order self-management efficacy model.

Instrument / Measurement Tool

The operational specifications of the SMEQ-PSO measurement tool are summarized below:

• Complete Tool Name: Self-Management Efficacy Questionnaire among Patients with Psoriasis (SMEQ-PSO)
• Primary Construct Assessed: Disease-specific self-efficacy across dermatological, daily lifestyle, medical, and psychosocial domains
• Assessment Methodology: Psychometric self-report questionnaire
• Item Count: 28 items
• Structural Dimensions (5 Subscales):
  • Subscale 1: Self-efficacy of Psychosocial Adaptation
  • Subscale 2: Self-efficacy of Daily Life Management
  • Subscale 3: Self-efficacy of Skin Management
  • Subscale 4: Self-efficacy of Disease Knowledge Management
  • Subscale 5: Self-efficacy of Disease Treatment Management
• Response Format: 5-point Likert scale:
  • 1 = Completely unconfident
  • 2 = Relatively unconfident
  • 3 = Moderately confident
  • 4 = Relatively confident
  • 5 = Absolutely completely confident
• Scoring Matrix: Individual item scores are summed to generate specific subscale scores, as well as a global composite self-management efficacy score. Theoretical composite scores range from 28 to 140 points.
• Score Interpretation: Higher cumulative and dimensional scores denote stronger perceived self-management efficacy. Low dimensional scores (≤ 2.0 to 2.5 item average) identify critical target areas for structured behavioral intervention, clinical psychoeducation, and counseling.
• Target Population: Adult patients (≥ 18 years of age) clinically diagnosed with psoriasis (plaque, guttate, inverse, or other forms).
• Original Language: Simplified Chinese (validated in mainland Chinese tertiary healthcare settings).
• Administration Modality: Self-administered (paper-and-pencil or secure electronic clinical interface); typical completion duration is approximately 8 to 12 minutes.

Permissions & Fee and Test Year

The SMEQ-PSO was originally published in 2023 in the peer-reviewed, open-access journal Health and Quality of Life Outcomes by Yuanhui Sun, Xiujie Zhang, Zhen Yang, and Aiping Wang.

• Licensing and Academic Use: The original validation research is distributed under the terms of the Creative Commons Attribution 4.0 International License (CC BY 4.0), which permits use, sharing, adaptation, distribution, and reproduction in any medium or format, provided appropriate credit is given to the original authors and the source.
• Commercial and Clinical Licensing: While the primary scholarly publication is open access, the exact, proprietary validated 28-item instrument inventory is protected by academic copyright. Commercial deployment, formal clinical trial integrations, translation into other languages, or inclusion within proprietary digital therapeutics platforms requires direct permission from the copyright holders.
• Access Contact: Inquiries regarding academic access to the full-text Chinese questionnaire items or authorization for cross-cultural translation and clinical validation should be directed to the corresponding developer, Dr. Aiping Wang, via email at [email protected].

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Items of the Scale