Partial support for this presentation was provided by the National Institute on Disability and Rehabilitation Research (H133A ) and by the Office on Disability and Health at the Centers for Disease Control and Prevention (R04/CCR714134) Disability: Concepts, Classification and Policy Theory, Classification, Models & Measures David B. Gray, Ph.D. Program in Occupational Therapy Washington University School of Medicine

Classification and Theory Classification provides nouns Theories describe relationships Postulates suggest test of relationships Hypotheses frame research questions Examples: Evolution and Intelligence

Purposes of Classification Nomenclature - what to name things, a language for common understanding Information retrieval - what is associated with name Description - what is and what isn’t A person with a disability is _________? Or disability includes _____? Prediction - if a thing, then what? If disabled then _______? Concept formation Sources of Disability are Biological and Social

Models of Classification Prototype Robins are prototypes for birds Problem - How to include new phenomena? Birds, flies and penguins do not Glen Close as prototype for borderline personality disorder as seen in the movie Fatal Attraction Case studies of people with specific diagnoses TBI, SCI, Polio and etc. have long been the way schools have trained practitioners for health care practice (see if you find this in your field work) DANGER: Greater variability (heterogeneity) within groups than a example (prototype) can provide

Models of Classification Dichotomous Perspective What are the boundaries of the concept or class? Intentional definitions define by listing required features Dichotomous is simple approach and has a long tradition Aristotle hoofs vs. no = 2 type of animals Problems – yes or no distinctions leads to many classes What features does one select? Blue eyes, hair color, height, weight, intelligence, wealth, skin color, religion… DISABLED & NOT DISABLED NORMAL & ABNORMAL Benefits - Easy to learn & great for information retrieval DANGER: Simple dichotomies do not predict (see also Nazi Germany’s approach to racial purity)

Models of Classification Monothetic model Classification is based on the presence of essential features that ‘cut nature at its joints’ Plato’s Republic vs. Absolutes Basis of the disease model – diseases are a single SET of physiological processes that stem from one underlying etiology (cause) - an abnormal process ex. Dyslexia as genetic Problem: assumption of homogeneity of defining characteristics BUT not all birds fly, diabetics do not have same physiological deficits, Trisomy-21 & LD have more than 1 cause DANGER: monothetic classification rules do not allow heterogeneity within a class, communicate more than may exist (DS=low IQ), assume single etiology, poor predictors of outcome (SSDI) and treatment (LD phonetic/whole word)

Models of Classification Polythetic model All features that define a category do not need to be present to make a positive classification. Rules describe the set of characteristics that form, a class of ____ 5 of 9 = bird 5 of 12 = attention deficit, 8/12 = depression, reading level 2 grades below class grade level = LD (not dyslexia) Allows for heterogeneity of phenotypes (observable features) within class. Clusters of features create relatively homogeneous groups without regard to etiology and allows for multiple causes. Ex. Immobility caused by SCI, sleep deprivation, broken leg(s), to much drinking but each show different clusters of variables DANGER: Classification rules may be unrelated to etiology & can expand to meet financial resources (LD, Autism)

Models of Classification Dimensional Model 1 Identifies variables that account for symptoms (phenotypes) Poor reading related to genes, family values, nutrition, financial means & method of instruction (each measurable) Arranges variables in higher orders of importance 35% family values, 30 % genes, 20% method of instruction 10% financial means, and 5% nutrition Does not require clusters of people to form classes, just values on various dimensions Dimensional approach provides a collection of values on variables that can can be positive or negative, which provides a profile of people on different dimensions

Models of Classification Dimensional Model 2 Problems No labels (nouns) for easy communication and description Clinicians avoid this approach because they need ‘things’ to heal and ‘things’ to report to third party payers for reimbursement Hard to organize scientific information – example textbooks have chapters on different diagnoses (SCI, TBI) not different underlying dimensions (mobility, memory). DANGER: Classification becomes measurement, inefficient for information retrieval, antithetical to medical/disease model, YOU WON’T GET PAID

Models and Classifications Applied to DISABILITY Medicine has a long history of case studies (prototype) guiding practice (blind/disabled children to adulthood pathway invariant) Early epidemiology was (dead or alive) and healthy or ill/diseased/disabled (dichotomous) International Classification of Disease classifies disease/disorders as traumatic brain injury, SCI, amputation = disabled (monothetic) DSM IV uses lists of features/symptoms for classifying psychiatric disorders. Examples: ADD, autism (polythetic) Danger: We are about to investigate dimensional approaches to understanding (?) disability YOU WILL NOT BE REIMBURSED FOR USING THIS APPROACH….YET!

Paradigm Shift in the Meaning of Disability Monothetic Classification Are Used in Reductionistic Sciences to Discover Nature’s Realities Medical or Person Only Factors Model Etiology Pathology Manifestation Dimensional Classifications Are Used in Holistic Explanations of Person Environment Interactions Models: Quebec and IOM Example of Classification is ICF

Paradigm Shift In “Science” Of Disability- Where Are Participation and Environment? Classification Etiology Body Level Person Level Social Level Contextual Level or Model 1965 Nagi Pathology Impairment Functional Disability Limitations 1980 ICIDH Disease Impairment Disability Handicap 1993 NCMRR Pathology Impairment Functional Disability Societal Limitations Limitations 1997 IOM Pathology Impairment Functional Disability Environment Limitations Level of Support 2001 ICF Health Body Functions Activity Limitations Environment Condition & Structures Participation Restrictions Barriers & Disease With & Without Facilitators (includes) Disorder Personal Assistance Personal Assistance Assistive Technology Influence on ParticipationAvailability

Interactive Models of Disability Disability is a complex phenomenon, neither solely an attribute of a person, nor solely a creation of the social environment There are different dimensions of disability (e.g. body level, person level, societal level) Dimensions of disability are distinct, and no dimension is more fundamental Trying to reduce disability to one dimension will always misrepresent it

Quebec Model: The Handicap Creation Process Patrick Fougeyrollas, Ph.D. Risk Factors Organic Systems Integrity - Impairment Capabilities Ability - Disability PERSONAL FACTORS ENVIRONMENTAL FACTORS Facilitator - Obstacle INTERACTION LIFE HABITS (MAJOR LIFE ACTIVITIES) Social Participation ---- Handicap Situation

Institute of Medicine The Enabling - Disabling Process Existing Physical & Social Environment Personw/Impairment Disabling Process: Person’s Needs Exceeds Environmental Resources Person w/o Impairment Enabling Processes A and B: Person’s Needs Are Met Within Environmental Resources A. Functional Restoration Existing Physical & Social Environment B. Environmental Changes Using Assistive Technology Personal Assistance Universal Design

Sequence of Concepts International Classification of Impairments, Disability and Handicap (ICIDH) 1980 Impairments Impairments Disease or ordisorder Disabilities Disabilities Handicaps

International Classification of Function (ICF) 2001 Impairment Activities (Activity Limitation) (Function/Structure) Participation (Participation Restriction) Health Condition (disorder/disease) Environmental Personal Factors Factors

International Classification of Functioning, Disability and Health Describes how people live with their health condition. A classification of health and health related domains Includes a list of environmental factors

Why Do We Need The ICF? Change in health care emphasis: acute to chronic conditions Change in focus: disease to function Need for ‘common language’ --across countries, disciplines, conditions, and populations Acknowledge environmental factors affecting the participation of people with disabilities in society

The ICF is not… The ICF is not an assessment or measurement tool. It is a framework and set of classifications on which assessment and measurement tools may be based, and to which they can be mapped. This distinction is often misunderstood, with people sometimes referring to the ICF itself as an assessment tool.

Foundations of ICF Human Functioning - not merely disability Universal Model - not a minority model Integrative Model - not merely medical or social Interactive Model - not linear progressive Context - inclusive - not person alone Cultural applicability - not western concepts Operational - not theory driven alone

ICF Applications Health sectorHealth sector Social securitySocial security Education sectorEducation sector Labour sectorLabour sector Economics & development sectorEconomics & development sector Legislation & lawLegislation & law Other ….Other ….

ICF: Contributions to Health Care Practice Provides a tool for the description of human functioning as multi-faceted Functional status often better indicator of treatment needs and outcomes than diagnosis alone Allows for a description of functioning in clinical and everyday environments

ICF Components Body Functions &StructuresActivities&Participation Environmental Factors BarriersFacilitatorsFunctionsStructuresCapacityPerformance

Body Functions and Structures Skin and related structures Functions of the skin and related structures Structures related to movement Neuromusculoskeletal and movement-related functions Structures related to the genitourinary and reproductive systems Genitourinary and reproductive functions Structures related to the digestive, metabolic and endocrine systems Functions of the digestive, metabolic and endocrine systems Structures of the cardiovascular, immunological and respiratory systems Functions of the cardiovascular, haematological, immunological and respiratory systems Structures involved in voice and speech Voice and speech functions The eye, ear and related structures Sensory functions and pain Structures of the nervous system Mental functions

Activities and Participation 1Learning &Applying Knowledge 2General Tasks and Demands 3Communication 4Movement 5Self Care 6Domestic Life Areas 7Interpersonal Interactions 8Major Life Areas 9Community, Social & Civic Life

Environmental Factors 1Products and technology 2 Natural environment and human made changes to the environment 3 Support and relationships 4Attitudes 5 Services, systems and policies

PAUSE FOR QUESTIONS

ACTIVITY & PARTICIPATION ActivityActivity –Perform Activities ParticipationParticipation –Engaged in Activities

Ability to DO Activity Inability to DO Activity DOESParticipate in Context DOES NOT Participate in Context Activity Assessment and Reported Participation A Dilemma A. Predicted +/+ D. Predicted -/- B. UNEXPECTED +/- C. UNEXPECTED +/- See Glass, 1998

Ability to DO Activity Inability to DO Activity DOESParticipate in Context DOES NOT Participate in Context Activity Assessment and Reported Participation A Dilemma A. Predicted Test shows that the person has Capacity to Do AND Do Participate +/+ D. Predicted Test shows that the person has No Capacity to Do and they do Not Participate -/- B. UNEXPECTED Test shows that the person CAN NOT DO BUT THEY Actually do Participate HOW? +/- C. UNEXPECTED Test shows that the person has the Capacity to Do BUT they Do Not Participate +/-

Low High ‘Normal’ Population Mobility Limited Population Capacity to Perform Activity in Clinic Used for justifying provision of medical care Performance Level Tests - Walking (SF-36 &FIM) AB Number of People Type 1 GAP

Low High Participation for ‘Normal’ and Disabled People in Lived Environment Participation - Moving Outside the Home A B Number of People Reduction of Type 1 Gaps by Changing the Outcome Measure Used from Capacity to Participation ‘Normal’ Population Mobility Limited Population

What is Participation and How Do We Measure Participation?

Participation: A Complex Construct PARTICIPATION FrequencyPreparation Time ImportanceChoiceSatisfaction Assistance from OthersAssistive Technology Personal Evaluation Temporal Receptive Environments

Instruments PARTS/MPARTS/M –Participation by Mobility Limited in Major Life Activities –Self-Report Measure –45 Minutes to complete –26 Activities FABS/MFABS/M –Facilitators and Barriers to Participation by Mobility Limited People –191 item assessment –30-40 Minutes to Complete

Polio Survivors: Participation in Major Life Activities: Importance, Choice & Satisfaction A Lot Some Little None High Imp Moderate Imp Low Imp

Quality of Participation Satisfaction –How satisfied are you with your participation in ‘this activity’? Four point likert scale – 1=Very satisfied, 2=Satisfied, 3=Somewhat satisfied, 4=Dissatisfied. Choice - To participate in ‘this activity’, how much choice do you have? Choice includes how, where, when and how often you participate in ‘this activity’. Four point likert scale – 1=A lot of choice, 2=Some choice, 3=Little choice, 4=No choice. Importance – How important is it for you to participate in ‘this activity’? Four point likert scale – 1=Very important, 2=Somewhat important, 3=Somewhat unimportant, 4=Not important.

What Is Environmental Receptivity? Services, Systems and Policies Products and Technology Natural Environments Human Made Changes to Environment Human Support and Relationships Attitudes PERSON Participation in Life Activities in the Community

Grocery Store Restaurants Hospitals Hotel Amusement Parks Theaters Surface Type Bathroom Access Climate Home Community School Work Personal Assistance Assistive Technology Accommodations Personal Employees at businesses Family Members Community Members Coworkers FABS/M Domains 1. Access to Frequently Visited Sites2. Environmental Features 3. Environmental Setting 5. Social Attitudes 4. Social Supports

Question Structure of FABS/M 1. Accessibility Limited? 2. Accessibility of Public Restrooms? 3. Accessibility of Home Environment? 4. Accessibility of Transportation? 5. Accessibility of Community? 6. Accessibility of Work/School? 7. Mobility Devices Used? 8. Access to Benefits, Agencies, Organizations? 9. Services and Attitudes?

FABS/M Reliability Internal Consistency and Test- Retest Reliability values for FABS domains ranged from.75 TO.93 in a study of polio survivors.Internal Consistency and Test- Retest Reliability values for FABS domains ranged from.75 TO.93 in a study of polio survivors.

Social Ecology Of People With Mobility Impairments And Limitations: Ecological Niche or Community Sites Of Sub-species - See Also Charles Darwin Niche of Homo sapiens erectus Niche of Homo sapiens situs: all mobility impaired & limited Community sites where mobility impaired & limited go without AT, PAS or receptive environment

Hypothesized Range Of Activities Participated In By People With Mobility Limitation With Different Types Of Devices People Without Mobility Limitations: Homo Erectus Limited Mobility Homo Situs Barriers to Mobility Device User Community Participation Important questions: How Far, How Frequent, How Important, Choice, Satisfaction, Access, Attitude? MobilityDevice Users A B C C B A

International Classification of Function (ICF) 2001 Impairment Activities (Limitation) with AT-, AT+ (Function/Structure) Participation (Restriction) with AT-, AT+ Health Condition (disorder/disease) Environmental Personal Factors AT-, AT+ Factors AT-, AT+

Participation in community activities at specific community sites: frequency, importance, choice and satisfaction Change in perception of the accessibility of built and natural environments: amount of support needed to participate, influence of barriers on participation AT Type C AT Type A Expansion Of The Ecological Niche Levels Of Analysis For Assessing The Influence Of Devices On The Expansion Of The Ecological Niche

Low Type C Device Distribution Of Participation By Environmental Receptivity For People With Mobility Impairments: Hypothetical Range Of Participation With Assistive Technologies A, B And C Level of Environmental Receptivity Type A Device Type B Device Participation Level MediumHigh Cut Point for Employ ment

Low High Mobility Limited Population With Type B Mobility AT The Quality of Participation for People with Impairments & Limitations in Mobility - Changing the Group MEAN Participation Levels A Number of People Type 2 Gaps: Within Group Differences B Range Mobility Limited Population With Type C Mobility AT