Mortality and Disability Years is a form accessed from a sub-option of the Specialized Displays for Issues sub-option of the Display Option on the Main Menu. This feature allows the user to display tables or graphs of key model forecast variables related to mortality and disability. Specifically, the user can see years of life lost (YLL; variable name HLYLL in IFs) as a result of age-specific mortality (the years of potential life lost from the death of a child are much more than those from the death of an adult). A subcategory of these years is years of working life lost (YLLWORK). Similarly, the form allows display of years of living with a disability (YLD) for the entire population or for those of working age (YLDWORK). The sum of Years of Life Lost (YLL) and Years Living with Disability (YLD) is defined to be Disability Adjusted Life Years (DALY) for the entire population and DALYWORK for those of working age.
The form allows all of these values to be shown not just in total, but by cause of mortality or morbidity (such as cardio-vascular disease or malaria).
The basic use of this form is similar to that of other features in the IFs program. Select one item from each of the boxes on the form and use the Graph or Table buttons at the bottom to obtain the display. On the form's menu, the sub-options under Grouping Options allow changing of the geography of displays from Countries/Regions to Groups, Decomposed Groups (showing all of the members of a group) or G-Lists (a large set of specialized geographical lists that can mix countries with groups of countries).
The Change Discount Rate menu option will be less familiar to most users. In financial analysis, a discount rate is often used to calculate the time value of money. Because money invested has a prospective return, the value of having it now is greater than the value of having it in future years. If that prospective return were 4% per year, the diminished worth of future money is estimated by "discounting" the money by a percentage for every year into the future. For instance, with a discount rate of 4%, $100 at year 1 is worth $100. At year 2, however, that $100 is worth $96; at year 3, $92.16; at year 4, $88.47, and so on.
In the health field it is similarly common to weight future years of life less heavily than the current one. A common discount rate is 3 percent and that is built in the displays generated from the form as a default. To change it, including the option of setting it to 0 and thereby turning off discounting, use the Discount Rate option under Change Discount Rate.
Discounting future years of life is a somewhat controversial concept in the computation of years of life lost. Perhaps an even more controversial one is age-weighting (the Global Burden of Disease uses both, so we include them in IFs along the ability to turn off either or both). Age weighting refers to the practice of assigning more value to certain years of life based upon its social role. For instance, one might consider working years more socially valuable than retirement years or those of childhood. Under the Age Weighting option the Beta parameter allows control over the age weighting but only a very rare user of IFs would want to exercise that control. For more information on discounting and age weighting formulations in IFs see the specialized document of the project on the health model.
Input the value you would like to use in the screen you are re-directed to and select Save. If you change the discount rate after having selected a graphic or table, that graphic or table will repaint to reflect the change.