How to Calculate QALY

Doctor

QALY is an acronym that stands for "Quality Adjusted Life Year." This is a medical term that describes an estimate of a person's life expectancy coupled with an estimation of the person's future quality of life. Calculating a person's QALY can help doctors and patients determine if a medical intervention is worthwhile. If an intervention makes a person live longer, but the quality of life is very poor, that patient (and doctor) may want to consider whether having the procedure is a good decision.

Difficulty:

Moderate

Instructions

1. Obtain a medical estimate concerning how long a patient is expected to live. This calculation is made based on a multitiude of factors such as existing medical conditions, severity of medical conditions, lifestyle, family history and overall physical health.

2. Obtain a medical estimate about the future quality of the years left to live. Physicians measure quality of life by evaluating multiple factors such as physical well-being, recreation, social relationships, community involvment and personal fulfilliment. For instance, a year of life that is half as enjoyable as a "normal" year for that individual would be measured as 0.5.

3. Multiply the estimates from steps one and two. For instance, if a patient is expected to live five years at 0.5 quality of life, the QALY would be 2.5 (the product of 5 x 0.5).

Tips & Warnings

• QALY is merely an estimate. This prediction is not definite as to a person's future length or quality of life.

References

• Bandolier Journal: QALY
• University of Pennsylvania: Mortality Calculator
• Quality of Life Outcomes: The Quality of Life Scale (QOLS): Reliability, Validity, and Utilization