EQ-5D-5L
The 5-level EQ-5D version (EQ-5D-5L) was introduced by the EuroQol Group in 2009 to improve the instrument’s sensitivity and to reduce ceiling effects, as compared to the EQ-5D-3L. The EQ-5D-5L essentially consists of 2 pages: the EQ-5D descriptive system and the EQ visual analogue scale (EQ VAS).
The descriptive system comprises five dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each dimension has 5 levels: no problems, slight problems, moderate problems, severe problems and extreme problems. The patient is asked to indicate his/her health state by ticking the box next to the most appropriate statement in each of the five dimensions. This decision results in a 1-digit number that expresses the level selected for that dimension. The digits for the five dimensions can be combined into a 5-digit number that describes the patient’s health state.
The EQ VAS records the patient’s self-rated health on a vertical visual analogue scale where the endpoints are labelled ‘The best health you can image’ and ‘The worst health you can image’. The VAS can be used as a quantitative measure of health outcome that reflects the patient’s own judgement.
Main differences between the EQ-5D-5L and the EQ-5D-3L
The EQ-5D-5L differs from the EQ-5D-3L on the following points:
- The number of levels of perceived problems per dimension was changed from 3 to 5, increasing the sensitivity and reducing the ceiling effect.
- The most severe label for the mobility dimension was changed from “confined to bed” to “unable to walk about”, enhancing its applicability and increasing the sensitivity of the mobility dimension.
- The instructions for the EQ VAS task were simplified, making the task easier to complete and easier to score.
EQ-5D-5L is available in more than 150 languages and in various modes of administration.