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Class 1Conceptualizing health (and its

determinants) and developing one’s own conceptual framework

September 21, 2006

Anita L. Stewart, Ph.D.Institute for Health & Aging

University of California, San Francisco

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Overview of Entire Class (Epi 225) How to critique and select good measures for your

own research Homework – weekly

– I will review and return to you each week– Basis for final paper

Two discussion sessions (optional)– 2:15-3:00– 4:30-5:00

Focus on one concept of interest to you– Health dimension or a determinant of health– Measurable (will need to find 2-3 measures to review)

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Overview of Class 1

Review classic conceptual frameworks of health and quality of life

Illustrate issues in defining a concept, how to depict concepts

Goal: provide ideas for developing your own concept before considering any measures

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Common Terminology of “Health”

Health indicators Health status Health outcomes Clinical status Functional status Functioning and well-being Quality of life Health-related quality of life

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Purposes of Assessing Health

As a dependent -Describe populations

variable -Compare groups

-Evaluate interventions (treatments)

-Evaluate policy changes

-Compare health plans Planning -Inform decision making

-Plan health services As a predictor -Of utilization of health services As a confounder -Control for case-mix

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Defining Health

Can you define health? What first comes to mind when you think

of the word “health”?

Health

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Defining Quality of Life

Can you define quality of life? What first comes to mind when you think

of the word “quality of life”?

Quality of Life

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Quality of Life Terminology

Overall satisfaction with life “as a whole” Well-being Global well-being Subjective well-being Sense of well-being Global happiness

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Two Classic Quality of Life Studies

A Campbell et al. The Quality of American Life, New York: Russell Sage Foundation, 1976.

FM Andrews and SB Withey. Social Indicators of Well-Being: Americans’ perceptions of Life Quality. New York: Plenum Press, 1976.

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Quality of Life Domains

Marriage Family life Health Neighborhood Friendships Housework Job City

Leisure Housing Money Standard of living Amount of education Savings Religion National government Local government

…. and many more

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Question

Can you imagine a question about the effect of health on quality of life?

HealthQuality of

Life

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Question

Can you imagine a question about the effect of health on quality of life?

HealthQuality of

life

Disease Satisfaction with life

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Defining Health-Related Quality of Life

Is health-related quality of life different than quality of life?

Can you define health-related quality of life?

Health-relatedquality of life

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Question

Can you imagine a question about the effect of health on health-related quality of life?

HealthHealth-related

quality oflife

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Question

Can you imagine a question about the effect of health on health-related quality of life?

HealthHealth-related

quality oflife

Disease Pain, well-being

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World Health Organization Definition of Health

“A state of complete physical, mental, and social well-being…”

“…not merely the absence of disease or infirmity.”

WHO, 1947

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What is Perfect Health?

An ideal toward which people are oriented – not a state they expect to attain.

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What is Perfect Health?

An ideal toward which people are oriented – not a state they expect to attain.

“A healthy person is someone who has been inadequately studied” (p. 31)

AC Twaddle, The concept of health status, Soc Sci Med 1974;8

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Health as a continuum?

Perfect health

Less than perfect health (normal)

Illness (abnormal)

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Varying Perspectives of Health?

Health

Bench scientist

Individual

Populationscience Clinician

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Population Science Perspective: Mortality and Morbidity

Mortality– All cause– Disease-specific (e.g., heart disease, stroke)– Population subgroup specific

» e.g., infant mortality

Morbidity– Presence of acute and chronic conditions

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Bench Scientist’s Perspective

Genetic markers Biomarkers Stem cells

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Clinician’s Perspective

Clinical status

– Anatomic, physiologic, biochemical indicators

– Symptoms and syndromes

– Diagnosed physical/mental conditions Requires clinician judgment and

physiological/laboratory tests

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Individual’s (Patient’s) Perspective

Functioning

Well-being

Health perceptions

Ability to perform basic functions and activities of daily life, usually observable

Internal, subjective feelings and perceptions (physical and emotional)

Beliefs about one’s health, known diagnoses

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Summary of Perspectives on Health Bench

Scientist Clinician Individual

Molecular, genetic, cellular X ??Anatomic, physiologic signs XSymptoms “X” XDiagnosed conditions X “X”Severity of conditions X XFunctioning in daily life XWell-being X

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Defining (and Measuring) Health from Individual’s Perspective

Includes specifying– Domains and subdomains (categories,

concepts)– Content areas of each domain or

subdomain– Response dimensions– Time frame

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Individual’s (Patient’s) Perspective

Functioning

Well-being

Health perceptions

Ability to perform basic functions and activities of daily life, usually observable

Internal, subjective feelings and perceptions (physical and emotional)

Beliefs about one’s health, known diagnoses

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Functioning

Ability to perform basic functions and activities of daily life, usually observable

Domains:– Physical functioning– Role functioning– Social functioning– Cognitive functioning

Are these all part of health? Why?– As clinicians, do you care about role and social functioning?

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Content Areas of Physical Functioning

Walking Running Climbing stairs, hills Bending, stooping Turning head Lifting, reaching, carrying Getting in/out of a chair,

car, toilet Dexterity

Climbing 1 flight of stairs

Climbing more than 1 flight of stairs

Walking 1 block Walking 3-4 blocks Walking 1 mile Kneeling Picking up an object

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Organizing Content Areas of Physical Functioning: One Example

Ambulation

Transferring

Upper extremity

Dexterity

Walking, climbing stairs

In/out of chairs, beds, cars,on/off toilet

Lifting, carrying, reaching,raising arms over head

Writing, holding utensils

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Role Functioning Content Areas

Ability to fulfill various social roles

Work, student Parent Caregiver Volunteer Spouse, partner

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Individual’s (Patient’s) Perspective

Functioning

Well-being

Health perceptions

Ability to perform basic functions and activities of daily life, usually observable

Internal, subjective feelings and perceptions (physical and emotional)

Beliefs about one’s health, known diagnoses

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“Well-Being”

Internal, subjective feelings and perceptions (physical and emotional)

Domains:– Psychological– Physical (e.g., symptoms such as fatigue,

pain)

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What is Physical Well-being?

Symptoms, bodily states reflecting physical discomfort (-)» Pain, discomfort

» Fatigue

» Sleep problems

» Malaise

» Other symptoms

Can physical well-being be defined? (+)» Energy?

» Feeling rested?

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Emotional or Psychological Well-being

Positive and negative emotional/affective states

Psychological distress and well-being Domains (-): Domains (+):

– Depression - Positive affect– Anxiety– Anger/irritability – Loneliness– Perceived stress

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Emotional Well-being vs DiagnosedMental Disorder

Positive and negative emotional/affective states

Domains on a continuum Domains as a disorder– Positive affect– Depressive symptoms Depression, dysthymia– Anxiety Anxiety disorder– Anger/irritability– Belonging/loneliness– Perceived stress PTSD

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Concept of Depression

What comes to mind when you think of the concept of depression as part of a research study of health?

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Depression

Affect(+ and -)Affect

(+ and -)Cognitions,evaluationsCognitions,evaluations SomaticSomatic Inter-

personalInter-

personal

Depression: Measurement Model

BehaviorBehavior

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Response Dimensions

Part of concept definition

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Types of Response Dimensions

State/level Level or state of behavior or feeling- Frequency (of a symptom)- Intensity (amount of difficulty)

Evaluative Value attached to level or state - Satisfaction (with health) - Bothersomeness (of a symptom) - Utility of a health state

Comparative Comparison to prior time, other persons

Agreement Level of agreement with statement

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Possible Response Dimensions for Physical Functioning (e.g., walking)

State/level

Evaluative

Comparative

Able/unable to do Extent of limitation Amount of difficulty Need for help Speed of completing defined task

Satisfaction with ability

Walking slower than 6 months ago

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Responses for Three Physical Functioning MeasuresDo you have any trouble... walking one block… ? (AIMS)

• Yes• No

Does your health limit you… in walking one block? (MOS, SF-36)• Yes, limited a lot• Yes, limited a little• No, not limited at all

Are you able to… walk one block? (HAQ)• Without any difficulty• With some difficulty• With much difficulty• Unable to do

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Possible Response Scales for Symptoms (e.g., pain, nausea)

Level/state

Evaluative

Comparative

Had it (yes/no) Frequency Intensity/severity (usually, at its worst Amount of time, # of days had it

Extent to which bothered by it Extent of distress due to it

Extent of change in (e.g. frequency) since prior time

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State/Level Response Scales for Sadness Items From 2 Depression Measures

Which best describes the way you felt in the past week? (Beck)• I do not feel sad• I feel sad• I am sad all of the time and I can’t snap out of it• I am sad all the time and I can’t stand it

How often have you felt “sad” during the past week? (CES-D)• Rarely or none of the time• Some or a little of the time• Occasionally or a moderate amount of time• All of the time

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Time Frame: Part of Concept Definition

Past:

Present:

No time frame:

Average experience over some previous time period (6 months, 3 months, 4 weeks, etc)

Current status - today, in general

Time frame not specified

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What are the Relationships Among Health Domains?

Are they just a lot of categories?– Different investigators define different categories

Is there some logical order among them? Very few conceptual frameworks of

relationships among health variables– Wilson and Cleary– Verbrugge and Jette

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MOS Framework: Functioning and Well-Being From the Patient’s Perspective

Physical functioning

Pain Energy/fatigue Sleep problems Cognitive functioning Psychological distress/well-being Social activity limitations due to health Role limitations due to physical health Role limitations due to emotional problems Current health perceptions

Stewart AL, Medical Outcomes Study FrameworkIn Stewart and Ware, 1992.

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MOS Framework: Functioning and Well-Being From the Patient’s Perspective

Physical Mental

Indicators Health Health Physical functioning X Pain X Energy/fatigue X X Sleep problems X X Cognitive functioning X Psychological distress/well-being X Social activity limitations due to health X X Role limitations due to physical health X Role limitations due to emotional problems X Current health perceptions X X

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MOS Framework: Functioning and Well-Being From the Patient’s Perspective

PhysicalHealth

MentalHealth

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Medical Outcomes Study SF-36 Framework Physical Mental

Indicators Health Health Physical functioning X Pain X Energy/fatigue X X Sleep problems X X Cognitive functioning X Psychological distress/well-being X Social activity limitations due to health X X Role limitations due to physical health X Role limitations due to emotional problems X Current health perceptions X X

JE Ware and CD Sherbourne, Med Care. 30: 1992

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Medical Outcomes Study SF-36 Framework Physical Mental

Indicators Health Health Physical functioning X Pain X Energy/fatigue X X

Psychological distress/well-being X Social activity limitations due to health X X Role limitations due to physical health X Role limitations due to emotional problems X Current health perceptions X X

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Physical Health

Physicalfunctioning

Physicalfunctioning PainPain

Vitality(energy/fatigue)

Vitality(energy/fatigue)

Role –physicalRole –

physical

MOS Physical Health: Measurement Model

Health perceptions

Health perceptions

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Conceptual Model of Patient Outcomes: Wilson and Cleary

Wilson IB and Cleary PD, JAMA, 1995;273:59

Biologicaland

physio-logical

variables

Symptomstatus

Overallquality of

life

Generalhealth

percep-tions

Functionalstatus

The Disablement Process:Verbrugge and Jette

Diagnosesof diseases,injury,congenital,development-al condition

Abnormalitiesin specificbody systems

Restrictionsin basic physical andmental actions

Difficulty doing activitiesof daily life dueto a healthproblem

Pathology FunctionalLimitations DisabilityImpairments

Soc Sci Med, 1994;38:1-14

Based on earlier models by Nagi, the ICIDH*, and IOM**

*ICIDH – International Classification of Impairments, Disabilities, and Handicaps**IOM – Institute of Medicine

The Disablement Process:Verbrugge and Jette

Pathology FunctionalLimitations DisabilityImpairments

Extra-individual andenvironmental factors

Intra-individual factorsRisk factors

The Disablement Process:Trajectory of Decline

Diagnosesof diseases,injury,congenital,development-al condition

Abnormalitiesin specificbody systems

Restrictionsin basic physical andmental actions

Difficulty doing activitiesof daily life dueto a healthproblem

Pathology FunctionalLimitations DisabilityImpairments

•Causal pathways not clear•As one moves to higher levels, factors other than pathology and impairments play greater role

The Disablement Process: Different Perspectives?

Pathology FunctionalLimitations DisabilityImpairments

Clinical perspective Individual’s perspective

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Summary

Substantial variation in definitions of health and health-related concepts

All health concepts are multidimensional– Many subdomains, components, response

dimensions Need to clarify concept definition prior to

selecting any measures