Schneider Institute for Health Policy Heller Graduate School Brandeis University September by Donald S. Shepard, Ph.D. Schneider Institute for Health Policy Heller School, MS 035 Brandeis University Waltham, MA USA Tel: Fax: Web: Monday, Sept. 17 Measuring effectiveness and other CEA considerations

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Practical information Teaching assistant: Administrative assistant: Linda Purrini, Next to library in Heller Cost of packet: $6.00

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Donald S. Shepard, Ph.D. Schneider Institute for Health Policy Heller School, MS 035 Brandeis University Waltham, MA USA Tel: Fax: Web: Measuring Effectiveness and Outcomes, QALYs and DALYs

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Outline Types of indexes Measuring national disease burden Health status questionnaires

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Needs for combining length and quality of life Assessing the disease burden of a country or a region, to see which health problems are greatest, and how one country or region compares with another. Evaluating a program that may impact both mortality and morbidity.

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Indexes for combining length and quality of life Quality Adjusted Life Years, QALYs (Zeckhauser and Shepard, 1976) Potential Days of Life Lost, PDLLs (Ghana health assessment team, 1980) Disability Adjusted Life Years, DALYs (World Development Report, 1993)

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Types of scales for assessing quality of life Value scale: a measure of preferences on a scale with arbitrary endpoints (example, SF36, scale of 0 to 100). Utility scale: a measure of preferences on a scale with endpoints of 0 and 1 and spacing consistent with probability theory.

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Burden of disease

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Ways of assessing utilities Probability approach – breakeven probability Time tradeoff - breakeven time

Schneider Institute for Health Policy Heller Graduate School Brandeis University September General health question In general, would you say your health is poor, fair, good, very good, or excellent? 1  poor 2  fair 3  good 4  very good 5  excellent

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Limitation of physical activities Here are a list of activities that you might do during a typical day. How much does your health limit you right now in moderate activities, such as moving a table, pushing a vacuum cleaner, bowling, or playing golf? 1  A lot 2  A little 3  Not at all

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Limitation of social activities During the past 4 weeks, how much of the time has your physical health or emotional problems interfered with your social activities like visiting with friends or relatives? 1  All of the time 2  Most of the time 3  A good bit of the time 4  Some of the time 5  A little of the time 6  None of the time

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Time tradeoff Time tradeoff - find the breakeven time Suppose we were to live 10 years with an impaired state, I Instead, we could live Y years with perfect health. Suppose the the value y would make us just indifferent. Then the utility of I is y / 10. E.g., if y is 7, then the utility is 7/10 = 0.70

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Von Neumann – Morgenstern Utility 1 Suppose we have a “good” outcome which has a utility of 1 (e.g. living year in perfect health) Bad outcome has a utility of 0 (e.g. dying at the start of the year) Intermediate outcome (I) has utility of x (e.g. living with a health limitation), x = u(I)

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Von Neumann – Morgenstern Utility 2 Suppose I is indifferent between probability p of good outcome, and 1-p of bad outcome The utility is von Neumann-Morgernstern if x equals p.

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Illustration: gastroenteritis in Ghana, c. 1980

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Remaining life expectancy by age, Ghana (1968)

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Disease burden for gastroenteritis (1): Mortality loss burden per death Days lost per death = Remaining life expectancy (years) at age of death 52.8 x Days per year = Days lost per death19,285

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Disease burden for gastroenteritis (2): Mortality loss burden per case Days lost per case from mortality = Case fatality rate0.01 x Days lost per death19,285 = Days lost per fatal case192.85

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Disease burden for gastroenteritis (3): Morbidity loss burden per case Days lost per non-fatal case = Average duration per surviving case (days) 14 x Proportion surviving0.99 = Days lost per non-fatal case13.86

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Disease burden for gastroenteritis (4): Total burden per case (days) Total days lost per case = Days lost per fatal case Days lost per non-fatal case13.86 = Days lost per case Note: Mortality share (% from fatal cases)93%

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Disease burden for gastroenteritis (5): Total annual burden per 1000 persons Total annual burden per 1000 persons = Total burden per case x Number of new cases per year (incidence) 70 = Total annual burden per 1000 persons 14,470

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Extensions: Discounting of health impacts Impacts in future years should be discounted, just as money is discounted Discounting arises due to “time preference”: –We are anxious to get good things soon. –If we have to wait, them “good” is less highly valued now.

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Discount factors

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Graph of discount factors (at 3%)

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Table of DALYs

Schneider Institute for Health Policy Heller Graduate School Brandeis University September DALYs from a life of specified number of years

Schneider Institute for Health Policy Heller Graduate School Brandeis University September Disease burden exercise Illustrate the calculation of PDLLs from exercise on web site