The Disability Adjusted Life Year (DALY) is calculated as DALY = YLL + YLD. In calculating Years Lived with Disability (YLD), the formula used is:

• A Number of prevalent cases × disability weight
• B Number of deaths × standard life expectancy at age of death
• C Number of incident cases × mean duration of disability × disability weight ✓
• D Incidence rate × case fatality rate × average age of onset

Explanation

YLD = Incidence of new cases × Duration of illness until remission or death × Disability weight (0–1 scale reflecting severity). This formula captures the burden of living with a non-fatal illness. YLL = Years of Life Lost to premature mortality = number of deaths × standard life expectancy at age of death. The DALY framework assigns disability weights based on health state descriptions, not case fatality or prevalence alone. The GBD (Global Burden of Disease) study uses this framework to compare burdens across diseases, countries, and time.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.