The Direct Healthy Life Expectancy Estimates from Life Tables to Support HALE Measures Done by the World Health Organization. A New Tool for a Standard Measure

Health-adjusted life expectancy (HALE) stands as the average number of years that a person is expected to live in good health by taking into account years lived in less than full health due to disease and/or injury. HALE can be assessed as a summary measure of healthy life expectancy over time. It can be estimated from only the data included in a life table as it was proposed and published a few years ago by Skiadas and Skiadas in papers mainly included in 45, 46 and 50 of The Springer Series on Demographic Methods and Population Analysis. The main idea was to use a formula for averaging the health estimates provided by mx = Dx/Px that is HLYL = max(xmx/sum(mx)) from 0 to age x, to estimate the Healthy Life Years Lost. In a way the average includes information for Deaths (Dx) and Population (Px) at age x and finds the mean information from 0 to x the same way people respond to questionnaires according to their experience over the years from deaths-injuries observed or/and information from decease and injury data collected is included. HALE estimates were achieved after the work of a well-organized team and the people working in this area succeeded in providing HALE as a figure measure for countries and specific areas. However, over the years, particular updates were needed to stabilize the final HALE figures as provided by the World Health Organization or by The Institute for Health Metrics and Evaluation (IHME). The last two updates continue to have differences, while the previous numbers of HALE starting from 2000 show particular differences. Researchers and policy makers have to adapt their models and programs to a changing situation though the need to adopt and apply a unique and standard Health State Measure is totally assessed. To this end, our research work concluded with replacing HALE with a unique health measure based on life tables, so that to have final estimates of Healthy Life Expectancy (HLE) for every particular Life Expectancy (LE). Many researchers have contributed in providing the HALE data we use, as Colin Mathers from WHO and Christopher Murray from IHME supported by numerous collaborators along with generous funding from Bill & Melinda Gates Foundation (BMGF). We deeply thank all of them for offering their findings as to finally check and verify a final model for estimating Healthy Life Expectancy (HLE). With our work here we provide a “Standard” measure to calculate replicable estimates for HLYL and then estimate the Healthy Life Expectancy (HLE) from HLE = LE-HLYL, where LE is the Life Expectancy.