Grantee Research Project Results
2003 Progress Report: Valuing Reduced Asthma Morbidity in Children
EPA Grant Number: R829665Title: Valuing Reduced Asthma Morbidity in Children
Investigators: Hanemann, Michael , Brandt, Sylvia
Institution: University of California - Berkeley , University of Massachusetts - Amherst
EPA Project Officer: Hahn, Intaek
Project Period: May 14, 2002 through December 31, 2006
Project Period Covered by this Report: May 14, 2003 through December 31, 2004
Project Amount: $328,205
RFA: Valuation of Environmental Impacts on Children's Health (2001) RFA Text | Recipients Lists
Research Category: Human Health , Children's Health , Environmental Justice
Objective:
Asthma is among the most important and dangerous childhood illnesses, causing one out of every six pediatric emergency room visits. In the United States, the direct cost of health care to treat asthma approaches $13 billion per year. In addition to the direct costs of asthma, morbidity itself has a quality-of-life impact on the household.
The objective of this research project is to investigate the willingness-to-pay to reduce asthma morbidity in children. We developed and administered two surveys to families with children with asthma in Fresno, CA. Using the survey data, we will analyze three main questions:
1. What are the determinants of households’ perceptions of asthma risks?
2. What are the averting/mitigating behaviors in the household?
3. What are the households’ stated willingness-to-pay for a reduction in their children’s asthma morbidity?
Progress Summary:
To develop the survey, we used an iterative process in which we discussed the most recent focus groups and interviews and built a consensus on the necessary changes. Each revision then was reviewed by all team members, which included two economists, a clinician, an epidemiologist, and two public health researchers. In the late spring of 2003, we conducted eight in-person household behavior surveys and followed each survey with debriefing questions. To prevent resurveying the study population, we recruited participants from an asthma clinic in Springfield, MA. A last round of revisions were made to the household survey reflecting comments and issues that arose during the in-person surveys.
During the fall of 2003, the team wrote the protocol for mailing the survey, contacting nonresponsive families, contacting respondents with incomplete surveys, and tracking all surveys and correspondence. A small pilot survey was conducted from November 2003 to January 2004. Respondents recorded that the survey took 35 to 45 minutes to complete. Asthma specialists then reviewed the final survey for completeness and accuracy.
In the spring of 2004, the household behavior surveys were mailed to all households participating in the Fresno Asthmatic Children’s Environment Study (FACES) and to households with an asthmatic child who was either ineligible or declined to participate in a longitudinal environment study. We extended the sample group to include families outside of FACES because recruitment for the epidemiological study was substantially lower than predicted. A total of 338 households were sent a survey (143 FACES participants and 195 FACES nonparticipants). Each household was contacted up to five times or until the survey was returned. The response rate is 86 percent for FACES participant households and 30 percent for non-FACES households. The significant barrier to increasing the response from non-FACES households was a change of address.
During the spring, we created the SAS screens for data entry and completed a protocol for entering the survey responses. Surveys were entered after they were verified to be complete with valid responses over the spring and early summer of 2004.
Preliminary Results
We have examined four aspects of household behavior: frequency of risk reducing behaviors, medication use, self-efficacy, and smoking in the household. There was a wide range of risk reducing behaviors reported, but common to all respondents was the increase in the monitoring of the child’s health. In cases where the child’s asthma was moderate to severe, some caregivers reported changing or terminating careers to have more time for supervision. This change in behavior suggests that household earning potential is an additional indirect cost to be included in cost-benefit analyses.
Although most respondents were able to identify their child’s asthma medications, there are discrepancies between the intended use of medications and actual use. The deviation between intended and actual use appears to be related strongly to perceived asthma severity.
There is evidence that self-efficacy in controlling asthma is influenced negatively by the duration of symptoms prior to diagnosis and treatment. The role of self-efficacy and risk reducing behavior varies over sociodemographic groups.
There is a notable lack of households among FACES participants that report that there is smoking in the household. We intend to pursue the question of sampling bias by comparing smoking rates to other populations in the Fresno area.
Potential Practical Application
This economic analysis of an asthma intervention will provide critical information to health care providers, public health departments, and policymakers. First, by examining household behavior, we can identify keys areas where asthma intervention programs can be directed effectively. Second, the estimates of willingness-to-pay for reduced asthma morbidity can be used to inform cost-benefit analyses of the reduction in asthma triggers.
Future Activities:
In the spring of 2004, we conducted 11 in-person tests of the contingent valuation instrument. We will focus on refining the contingent valuation scenario and payment vehicle in the next stage. A second round of tests of the contingent valuation survey is scheduled for October 2004.
We will use the data from the household behavior survey to analyze the relationships between households’ perceptions of risks, their mitigating/averting behavior, and their objective risks. First, we will use the data to estimate a Health Belief Model. Second, we will estimate a household health production function to derive a revealed willingness-to-pay from reduced asthma morbidity. We will be presenting the preliminary results at the American Public Health Association meetings in November 2004.
Journal Articles:
No journal articles submitted with this report: View all 5 publications for this projectSupplemental Keywords:
health, children’s health, economics, air pollution, behavioral science research, exposure, risk, risk assessment, effects, health effects, human health, sensitive populations, children, public policy, decisionmaking, cost benefit, observation, nonmarket valuation, contingent valuation, survey, psychological, preferences, socioeconomic, willingness-to-pay, sociological, economics research, social sciences research,, RFA, Scientific Discipline, Economic, Social, & Behavioral Science Research Program, Health, Geographic Area, Health Risk Assessment, State, Susceptibility/Sensitive Population/Genetic Susceptibility, Environmental Monitoring, Allergens/Asthma, Ecological Risk Assessment, decision-making, Children's Health, genetic susceptability, Economics & Decision Making, Social Science, social psychology, surveys, behavioral effects, asthma, contingent valuation, sensitive populations, social impact analysis, valuation, morbidity, random utility model, air toxics, economic valuation, decision analysis, incentives, ozone, behavioral assessment, airway disease, risk perception, children's health values, preference formation, air pollution, environmental values, survey, airway inflammation, children, willingness to pay (WTP), adult valuation of children's health, asthmatic children, psychological attitudes, environmental health hazard, children's environmental health, environmentally caused disease, stated preference, willingness to pay, California (CA), economic objectives, behavior reactions, asthma morbidityProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.