Physical Disability Identity Scale (PDIS)

Abstract

The Physical Disability Identity Scale (PDIS), developed by Rule et al. (2025), is a specialized instrument designed to measure the degree to which individuals with physical disabilities integrate their disability status into their overall sense of self. The scale development followed rigorous psychometric procedures across two studies utilizing a sample of adults with physical disabilities in the United States. Initial development began with a 34-item pool, which included 14 items adapted from the established Multicomponent In-Group Identification Scale. Through subsequent refinement, the scale was reduced and finalized to 21 items. Statistical analysis, including both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA), provided strong evidence supporting a robust six-factor structure for the PDIS. Detailed documentation regarding the scale’s validity and reliability is available in the original publication.

Keywords

Centrality, Connection, Disability Lens, Face Validity, Individual Self-Stereotyping, Openness, Physical Disability, Satisfaction, Self-Concept, Well-Being, Disabilities, Physical Disabilities (Attitudes Toward), Social Identity, Health Attitude Measures.

Authors

Rule, Payton D., Ratner, Kaylin, Willroth, Emily C., Hill, Patrick L.

Purpose

The primary objective of the PDIS is to provide a quantitative assessment of physical disability identity among adults living with physical disabilities or reduced mobility. This measurement tool allows researchers and clinicians to understand the multifaceted nature of identity integration related to physical impairment.

By quantifying this identity construct, the PDIS facilitates studies examining how different components of disability identity correlate with psychosocial outcomes, including well-being, self-efficacy, and social integration.

Construct

The PDIS measures Physical Disability Identity, conceptualized as a multidimensional construct rooted in the principles of Social Identity theory. The final 21-item scale is structured around six distinct factors, each representing a specific facet of identity integration:

• Connection: Reflects feelings of belonging, commitment, and solidarity with other people who have physical disabilities.
• Satisfaction: Measures positive affective evaluation, such as pride and contentment, regarding identifying as a person with a physical disability.
• Centrality: Assesses the importance of physical disability status to the individual’s overall self-concept.
• Openness: Relates to the comfort level in disclosing or discussing the disability with others, and the extent of concealment efforts.
• Individual Self-Stereotyping: Reflects the perceived similarity between the individual and the broader community of people with physical disabilities regarding shared experiences and challenges.
• Disability Lens: Captures the extent to which the physical disability shapes the individual’s worldview and their approach to life and social interactions.

Validity

The validity of the PDIS was established through analysis comparing its factors to existing theoretical constructs and measures of psychological adjustment. The factors demonstrated strong convergent validity, particularly with the established Multicomponent In-Group Identification Scale (Leach et al., 2008). Specifically, the Connection and Satisfaction factors showed significant alignment with the solidarity subscale of the Multicomponent In-Group Identification Scale.

Furthermore, the factors exhibited differential relationships with external outcome measures:

• The Centrality factor was found to be adversely related to general measures of well-being.
• The Openness factor was positively associated with adaptive outcomes, including a sense of purpose, life satisfaction, social support, and self-efficacy, while also predicting lower levels of derailment.
• The Individual Self-Stereotyping factor showed complex relationships, being both adaptively and adversely associated with various health and well-being constructs.
• The Disability Lens factor was consistently and adversely associated with both well-being and health-related constructs.

Reliability

The scale demonstrated high internal consistency across all six factors, as measured by Cronbach’s alpha coefficients. The alpha values ranged from 0.70 to 0.95, indicating strong reliability for both general research and specific clinical applications.

The internal consistency values for the specific factors are reported as follows:

• Connection: α = 0.95
• Satisfaction: α = 0.86
• Centrality: α = 0.79
• Openness: α = 0.82
• Individual Self-Stereotyping: α = 0.70
• Disability Lens: α = 0.91

Factor Analysis

The scale’s underlying structure was rigorously tested using both exploratory and confirmatory methods. The Exploratory Factor Analysis (EFA) utilized multiple extraction and retention methods, including parallel analysis, optimal coordinates, and the Kaiser criterion, all of which consistently supported a six-factor model. This process led to the removal of six items (five that did not align strongly with any factor and one that cross-loaded), resulting in the final 21-item scale.

Following item refinement, factor loadings were determined: Connection (0.79 to 0.95), Satisfaction (0.75 to 0.82), Centrality (0.42 to 0.69), Openness (0.53 to 0.81), Individual Self-Stereotyping (0.65 to 0.89), and Disability Lens (0.60 to 0.73). The subsequent Confirmatory Factor Analysis (CFA) provided support for the identified six-factor structure with favorable fit indices: RMSEA = 0.073, CFI = 0.931, Tucker-Lewis index = 0.917, χ²(174) = 450.53 (p < 0.01), and SRMR = 0.073. All included items maintained loadings above 0.30 on their respective factors.

Instrument

Test Type: Original

Format: Items are rated on a 7-point scale (1 = strongly disagree to 7 = strongly agree).

Language Available: English

Population Group: Human; Male; Female; Transgender

Age Group: Adulthood (18 years & older)

Population Details: The scale was standardized and administered to adults residing in the United States who identify as having physical disabilities or reduced mobility. The sample included diverse gender identities such as Male, Female, Transgender, Genderqueer, and Other.

Test Methodology: The scale’s development and validation methodology incorporated: Test Validity, Test Reliability, Internal Consistency, Factor Analysis, Confirmatory Factor Analysis, and Exploratory Factor Analysis.

Keywords

Physical Disability Identity, Psychometric properties, Rehabilitation Psychology, Disability Community, Self-Efficacy, Life Satisfaction, Social Support, Group Identification, Identity Centrality.

Authors

Author ORCID Identifier: http://orcid.org/0009-0000-1559-193X (Payton D. Rule)

Affiliation Email addresses: [email protected] (Rule, Payton D.)

Correspondence Address: Rule, Payton D.: Washington University in St. Louis, Department of Psychological & Brain Sciences, 316D Somers Family Hall, Forsyth Boulevard, St. Louis, Missouri, United States, 63105.

Permissions & Fee and Test Year

Permissions: May be used for Research/Teaching
Fee: No
Test Year: 2025

Reference’s

Rule, P. D., Ratner, K., Willroth, E. C., & Hill, P. L. (2025). Development and validation of the Physical Disability Identity Scale: A multistudy quantitative investigation with participant feedback. Rehabilitation Psychology. Advance online publication. https://doi.org/10.1037/rep0000606

Leach, T. M., van Zomeren, M., Zebel, S., Vliek, M. L., Pennekamp, S. F., Doosje, B., Ouwerkerk, J. W., & Spears, R. (2008). Group-level self-definition: A conceptual and operational analysis. Journal of Personality and Social Psychology, 95(1), 144–165.

Forber-Pratt, A. J., Young, R. A., & Balcells, A. (2022). Predictors of disability identity development in college students. Rehabilitation Psychology, 67(1), 1–12.

Hahn, H., & Belt, R. W. (2004). Disability identity and attitudes toward cure in a sample of people with spinal cord injuries. Journal of Health and Social Behavior, 45(4), 463–476.

Items of the Physical Disability Identity Scale (PDIS)

Physical Disability Identity Scale

(Connection)
I feel connected to other people with physical disabilities.
I feel solidarity with people with physical disabilities.
I feel committed to people with physical disabilities.
I feel a sense of belonging with other people with physical disabilities.

(Satisfaction)
Overall, I am glad to be a person with a physical disability.
I am proud to identify as a person with a physical disability.
I feel content with being a person with a physical disability.

(Centrality)
The fact that I am a person with a physical disability is an important part of my identity.
Being a person with a physical disability is an important part of how I see myself.
I view my physical disability similarly to the way I view my other identities (race, gender, etc.).
I refuse to see my physical disability as a part of how I see myself.

(Openness)
I feel comfortable talking about my physical disability with others.
I feel embarrassed or ashamed when others ask me about my physical disability, even if they are well intentioned.
I do my best to conceal/hide my physical disability from others.

(Individual self-stereotyping)
I have a lot in common with others with physical disabilities.
I am similar to other people with physical disabilities.
I experience a lot of similar challenges as other people with physical disabilities.
I view physical disability similarly to others in the disability community.

(Disability lens)
Being a person with a physical disability shapes how I see the world.
Being a person with a physical disability shapes how I interact with others.
Being a person with a physical disability shapes how I approach life.

Note. Items are rated on a scale of of 1 = strongly disagree to 7 = strongly agree.