Generic measure of health related quality of life
The EQ-5D-5L is a validated generic instrument for measuring patients’ general health status and is an extended version of the EQ-5D-3L. Two levels were added to this improved version in order to reduce the ceiling effect and increase the sensitivity of the 3-level version. The content of this tool is split into two parts: the EQ-5D descriptive system and the EQ visual analogue scale (VAS).
The first consists of 5 questions assessing the patient’s mobility, self-care, usual activities, pain/discomfort and anxiety/depression. The EQ VAS evaluates the patient’s general state of health. The instrument has been used in various medical disciplines, including orthopedics, oncology and pneumology.
Items - Dimensions - Completion time
Each of the five questions can be answered by selecting 1 of 5 health levels: no problems, slight problems, moderate problems, severe problems and extreme problems. After all items have been answered, a unique health status is calculated by combining the number of the level selected for each question into a single number, for example 12445.
There are a total of 3,125 (i.e., 55) health statuses possible. Skipped items are allocated a score of “9.” The EQ VAS score is stated separately as the number the patient selected (e.g., 73). If the VAS is skipped, a score of “999” is allocated.
From the unique health status, a single summary index value is generated using a general population-based value set. The scoring concept is based on the time trade-off method (patients decide how many years of symptom-free life they would equate to 10 years of life in their current state of health). 7
The patient’s health status can be represented with an EQ-5D single summary index value and a VAS score. A value of 1 indicates the best possible health status, whereas lower scores are linked with health deficits and scores below 0 can be interpreted as “worse than death.”