Background-The Panel on Cost-Effectiveness in Health and Medicine has called for an "off-theshelf" catalogue of nationally representative, community-based preference scores for health states, illnesses, and conditions. A previous review of cost-effectiveness analyses found that 77% did not incorporate community-based preferences, and 33% used arbitrary expert or author judgment. These results highlight the necessity of making a wide array of appropriate, community-based estimates more accessible to cost-effectiveness researchers.

OBJECTIVE -Given the risk of obesity and diabetes in the U.S., and clear benefit of exercise in disease prevention and management, this study aimed to determine the prevalence of physical activity among adults with and at risk for diabetes.RESEARCH DESIGN AND METHODS -The Medical Expenditure Panel Survey is a nationally representative survey of the U.S. population. In the 2003 survey, 23,283 adults responded when asked about whether they were physically active (moderate or vigorous activity, Ն30 min, three times per week). Information on sociodemographic characteristics and health conditions were self-reported. Additional type 2 diabetes risk factors examined were age Ն45 years, non-Caucasian ethnicity, BMI Ն25 kg/m 2 , hypertension, and cardiovascular disease.RESULTS -A total of 39% of adults with diabetes were physically active versus 58% of adults without diabetes. The proportion of active adults without diabetes declined as the number of risk factors increased until dropping to similar rates as people with diabetes. After adjustment for sociodemographic and clinical factors, the strongest correlates of being physically active were income level, limitations in physical function, depression, and severe obesity (BMI Ն40 kg/m 2 ). Several traditional predictors of activity (sex, education level, and having received past advice from a health professional to exercise more) were not evident among respondents with diabetes.CONCLUSIONS -The majority of patients with diabetes or at highest risk for developing type 2 diabetes do not engage in regular physical activity, with a rate significantly below national norms. There is a great need for efforts to target interventions to increase physical activity in these individuals.

The preference-based chronic condition scores reported in this research are nationally representative and may be useful to researchers to calculate quality-adjusted life-years for cost-effectiveness analyses and population-based burden of illness studies without the difficulty of primary data collection. Further research is necessary to validate these scores in condition-specific studies.

. This research provides community-based EQ-5D index scores for a wide variety of chronic conditions that can be used to estimate QALYs in cost-effectiveness analyses in the UK. Although using EQ-5D questionnaire responses from the US-based MEPS is less than ideal, the estimates approximate HRQL guidelines by NICE and provide an easily accessible"off-the-shelf" resource for cost-effectiveness and public-health applications.