Other Patient-Level Economic Outcomes

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Other Patient-Level Economic Outcomes

• Todd Wagner, PhD
• August 8th, 2007

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Outline of Talk

• Willingness to pay
• Employment and (lost) productivity

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Economic Theory

• A persons happiness is dependent on
• her consumption of non-health goods (X)
• her health (H)
• where consumption is limited by income and time
  (Y)
• Without mammogram V(Y,Px,H)
• Getting a mammogram costs time and money
• Trade off for a mammogram -- WTP
• V(Y,Px,H) V(Y-WTPmam,Px,H)

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Revealed Preferences

• Analyses of consumption data provide information
  on revealed preferences
• For example, consumers show a preference for
  iPods over other MP3 players
• Economists can use this information to estimate
  social welfare in a cost-benefit analysis

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Contingent Valuation

• Hard to observe revealed preferences in health
  care because of market distortions.
• Exceptions for travel costs
• Clarke, P. M. (1998). JHE, 17(6), 767-787.
• Kessler, D. (2005) NBER Working Paper 11419
• If preferences are not observable, perhaps they
  can they be elicited
• Contingent valuation

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Willingness to Pay

• WTPcv can be used as an alternative to utility
  and QALYs
• Hereafter I use WTP to refer to WTPcv
• WTP can be used in a cost-benefit analysis or as
  preference measure

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Overview

• What would I be willing to pay to avoid x or
  gain y?
• Academic research roots in environmental
  economics
• Also used in marketing

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Benefits of WTP

• People understand the concept
• Explicit tradeoff
• Adheres to neoclassical economic theory
• Many people pay for health care
• Dollar an easy to understand unit as opposed to
  risks
• May be responsive to small effect not detected
  with utilities

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Drawbacks of WTP

• Insurance obscures charges and reduces risk
• Correlation with income makes many practitioners
  uncomfortable
• Validity is extremely dependent on framing of
  question and response scale
• Vulnerable to social desirability
• No limit on willing to pay
• Never willing to pay

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What to Ask

• User based ex-post vs. insurance based ex-ante
• Who pays public versus private
• Results certainty or uncertain
• Framing
• Realism of task
• Extent of description

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Who to Ask

• Everybody that could potentially benefit
• Only those that directly benefit

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Mode of Administration

• In person interviewing
• can positively bias responses through social
  desirability
• Allows for probes and potentially greater
  accuracy
• Paper and web surveys
• May avoid social desirability
• Any confusion may not be resolved

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Response Categories

• Preferred
• Payment cards/scales
• Maximum amount is WTP
• This method biases estimates of variation
• Dichotomous response
• Randomly assign price, person asked yes or no
• Requires large sample
• WTP is estimated in a maximum likelihood logit
  model
• Avoid
• Open ended
• Bidding games

• NOAA. (1992). Report of the National Oceanic and
  Atmospheric Administration. Federal Registry,
  58(10), 4601-4614.

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Question Development

• WTP question must be tailored for each study
• No standard WTP question
• Pre-testing is highly recommended
• Dillman method
• Modify the question
• Identify the response scale range
• Assess validity
• Correleted with income
• Scope WTP should vary by scope of benefits
• Dillman, D. (2000). Mail and Internet Surveys
  The Tailored Design Method (Second ed.). New
  York John
• Wiley and Sons, Inc.

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Example

• Pathfinders NCI funded behavioral intervention
  that sought to improve cancer screening among
  ethnically diverse women in the SF. Bay Area.

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Focus Groups

• Conducted focus groups and individual interviews
  with low income women representing five race /
  ethnic groups (African American, Chinese,
  Filipino, Latino, and white) and four languages
  (English, Chinese, Spanish and Tagalog).
• Focus group facilitators were women of
  approximately the same age and same
  race/ethnicity
• All focus groups were tape recorded with consent

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Question Development

• Discussed use of mammography, paying for health
  care
• Showed example WTP questions and had them discuss
  them
• Identified range of WTP responses
• Forward and back translation into non-English
  languages

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WTP Question

• The next questions ask how important you think
  mammograms are. I am going to ask how much you
  would be willing to pay to get a mammogram.
  Please be assured that answering these questions
  will not increase the cost of any medical
  services. Your answer simply tells us what the
  mammogram is worth to you in dollars. Okay, here
  are the questions.
• 1. Many women get mammograms free of charge. But
  suppose that there was no way to get a free
  mammogram. Would you get a mammogram if it cost
  75?
• (PROBE) Considering what you can afford right
  now, would you be willing to pay 75 for a
  mammogram?

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Question Validation

• The validity was tested with a random sample of
  52 low-income, ethnically diverse women in the
  San Francisco area.
• Internal validity correlation with income
• Construct validity correlation with past
  behaviors

Wagner, T. H., Hu, T.-w., Dueñas, G. V.,
Pasick, R. J. (2000). Willingness to pay for
mammography item development and testing among
five ethnic groups. Health Policy, 53(2), 105-121.
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Pathfinders Intervention

• Enrolled 1463 women
• Collected baseline data, including WTP
• Randomized to educational intervention and
  control (usual care)
• 24 month follow-up

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Baseline data

• 1419 respondents as of early-April 2000

final ethnicity Freq.
Percent -----------------------------------------
----- Black/African American 499
35.17 Chinese 181
12.76 Filipina 142
10.01 Latina 297
20.93 White 300
21.14 -------------------------------------------
--- Total 1419
100.00
Wagner, T. H., Hu, T.-w., Dueñas, G. V., Kaplan,
C. P., Pasick, R. J., Nguyen, B. H. (2001).
Does willingness to pay vary by race/ethnicity?
An analysis of mammography among low-income
women. Health Policy, 58, 275-288.
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Sample Characteristics

• Survey in English 996 (70)
• 39 of sample was foreign born
• Proportion of life in US
• Black/African American 0.99
• Chinese 0.33
• Filipina 0.40
• Latina 0.52
• White 0.97

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Baseline characteristics (cont.)

• 1.14 had never heard of mammogram
• 87 had a mammogram in their lifetime
• 83 had mammogram in last 5 years
• Stages of change
• precontemplation 5
• contemplation 30
• action 12
• maintenance 38
• relapse 14

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WTP

• Average WTP 131 (SD 92 Range 0-500)

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WTP by stages of change
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Mother, daughter or sister with breast cancer
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Thistles and Thorns

• Refused to answer 4 (0.3)
• Dont know 26 (1.8)
• No limit 95 (6.7)
• Pay nothing 55 (3.9)

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WTP and CBA

• Cost benefit analysis compares costs to monetized
  benefits
• CEA exists because people prefer QALYs over
  monetized benefits
• WTP is a measure of monetized benefits
• Net benefitWTP-Costs
• Objective function net benefit gt0

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Employment Outcomes
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Employment

• Employment outcomes are typically excluded from a
  CEA because these effects are included in the
  denominator (QALYs).
• However, employment may be an important outcome
  in its own right or
• CEA may be using another outcome that does not
  reflect employment (e.g., mortality)

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Typical (Bad) Questions

• Are you currently working at a paying job?
• ? Full time
• ? Part time
• ? Not working
• Please check one of the following
• ? working full time
• ? working part time
• ? homemaker
• ? student
• ? unemployed
• ? retired

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BLS on Being Employed

• Persons 16 years and over in the civilian
  noninstitutional population who, during the
  reference week, (a) did any work at all (at least
  1 hour) as paid employees worked in their own
  business, profession, or on their own farm, or
  worked 15 hours or more as unpaid workers in an
  enterprise operated by a member of the family
  and (b) all those who were not working but who
  had jobs or businesses from which they were
  temporarily absent because of vacation, illness,
  bad weather, childcare problems, maternity or
  paternity leave, labor-management dispute, job
  training, or other family or personal reasons,
  whether or not they were paid for the time off or
  were seeking other jobs. Excluded are persons
  whose only activity consisted of work around
  their own house (painting, repairing, or own home
  housework) or volunteer work for religious,
  charitable, and other organizations.

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Unemployed

• Persons aged 16 years and older who had no
  employment during the reference week, were
  available for work, except for temporary illness,
  and had made specific efforts to find employment
  sometime during the 4-week period ending with the
  reference week. Persons who were waiting to be
  recalled to a job from which they had been laid
  off need not have been looking for work to be
  classified as unemployed.

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Out of Labor Force

• People who are not employed and not actively
  looking

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Class Exercise

• For employment status, how does BLS classify
• military personnel
• veterans
• prison inmates

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Measuring Employment

• Paid employment
• Employer (self or company)
• Hours of employment
• Productivity / lost productivity
• Absenteeism / presenteeism
• Income / assets
• Occupation (typically of little value)

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Employment Matters

• Diseases can affect overall employment
• Depression
• Arthritis
• Stroke
• Back pain
• Diseases can affect willingness to start own
  company
• Depression

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Productivity

• Many illnesses can affect productivity and
  absenteeism
• Migraine
• Incontinence
• Ulcers
• Depression
• Substance Use
• Back pain

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Questionnaires

• No gold standard exists for employment, assets,
  and income
• Many people use questions from national surveys
• PSID (Panel Study of Income Dynamics)
• AHEAD (Asset and Health Dynamics Among the Oldest
  Old)
• HRS (Health and Retirement Survey)
• Bureau of Labor Statistics (www.bls.gov/ers/home.h
  tm)
• Two measures of lost productivity

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Example of Tailored Questions

• Partners in Care (depression)
• http//www.rand.org/health/projects/pic/measures/t
  cimeasure/cidi-tci.html
• 23 pages of detailed questions on assets, income,
  wealth for respondent and family.
• Based on Health and Retirement Survey.

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Heath and Work Performance Questionnaire (HPQ)

• http//www.hcp.med.harvard.edu/hpq/
• How many hours does your employer expect you to
  work in a typical 7-day week?
• In the past 4 weeks (28 days), how many days did
  you...
• ...miss an entire work day because of problems
  with your physical or mental health?
• ...miss part of a work day because of problems
  with your physical or mental health? (Please
  include only days missed for your own health, not
  someone elses health.)

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Work and Health Interview

• In the past 4 weeks, how many hours per week, on
  average, did you work? ______________ of
  hours
• In the past 4 weeks, how many total, full days of
  work did you miss for health reasons? These would
  be days you did not go to work at
  all. ______________ days
• For a number of reasons (illnesses, poor
  concentration, fatigue) people are not as
  productive as they can be at work all the time.
  In the past 4 weeks, how many hours per week, on
  average, were you not productive?
• ______________ of hours

• Note wording from earlier version and it may
  have changed
• Stewart et al. Lost Productive Time Due to Common
  Pain JAMA 2003

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Barriers to Measuring Employment

• People who receive public benefits face a
  disincentive to work
• Income from work must outweigh benefits
• Incentives to work under the table
• Incentives to bill years work in a month or two
• These perverse incentives lead Congress to
  enact the 1996 welfare reforms
• Veterans who receive means-tested public benefits
  also face a disincentive

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Other Problems

• For an outcome measure, avoid using labeled
  categories (e.g., full time or part time)
• Measure hours of work
• Other issues to consider
• Unions
• Worksite health programs
• Childcare
• Health of family members