Title: Other Patient-Level Economic Outcomes
1Other Patient-Level Economic Outcomes
- Todd Wagner, PhD
- August 8th, 2007
2Outline of Talk
- Willingness to pay
- Employment and (lost) productivity
3Economic 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)
4Revealed 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
5Contingent 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
6Willingness 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
7Overview
- What would I be willing to pay to avoid x or
gain y? - Academic research roots in environmental
economics - Also used in marketing
8Benefits 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
9Drawbacks 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
10What 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
11Who to Ask
- Everybody that could potentially benefit
- Only those that directly benefit
12Mode 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
13Response 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.
14Question 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.
15Example
- Pathfinders NCI funded behavioral intervention
that sought to improve cancer screening among
ethnically diverse women in the SF. Bay Area.
16Focus 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
17Question 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
18WTP 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?
19Question 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.
20Pathfinders Intervention
- Enrolled 1463 women
- Collected baseline data, including WTP
- Randomized to educational intervention and
control (usual care) - 24 month follow-up
21Baseline 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.
22Sample 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
23Baseline 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
24WTP
- Average WTP 131 (SD 92 Range 0-500)
plt.0001
25WTP by stages of change
plt.0001
26Mother, daughter or sister with breast cancer
27Thistles and Thorns
- Refused to answer 4 (0.3)
- Dont know 26 (1.8)
- No limit 95 (6.7)
- Pay nothing 55 (3.9)
28WTP 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
29Employment Outcomes
30Employment
- 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)
31Typical (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
32BLS 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.
33Unemployed
- 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.
34Out of Labor Force
- People who are not employed and not actively
looking
35Class Exercise
- For employment status, how does BLS classify
- military personnel
- veterans
- prison inmates
36Measuring Employment
- Paid employment
- Employer (self or company)
- Hours of employment
- Productivity / lost productivity
- Absenteeism / presenteeism
- Income / assets
- Occupation (typically of little value)
37Employment Matters
- Diseases can affect overall employment
- Depression
- Arthritis
- Stroke
- Back pain
- Diseases can affect willingness to start own
company - Depression
38Productivity
- Many illnesses can affect productivity and
absenteeism - Migraine
- Incontinence
- Ulcers
- Depression
- Substance Use
- Back pain
39Questionnaires
- 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
40Example 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.
41Heath 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.)
42Work 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
43Barriers 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
44Other 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