Responsiveness of the EQ-5D to HADS-identified anxiety and depression.
BACKGROUND
The use of generic measures of health-related quality of life enables cost effectiveness comparisons of different health care interventions to be made. Nevertheless, there exists a concern that generic instruments may be insufficiently sensitive to detect the differences or changes in outcome identified by condition-specific instruments. This paper compares the psychometric properties of the EQ-5D generic instrument with a widely used specific measure of distress, the Hospital Anxiety and Depression Scale (HADS).


METHODS
The analysis was based on data obtained from a large sample of women (n = 3119) with low-grade cervical cytological abnormalities detected at routine screening. These women completed EQ-5D and HADS questionnaires at recruitment and at 12 months thereafter. We examined the strength of association between HADS-determined severity of distress and EQ-5D scores at recruitment and between changes in severity and in scores over time.


RESULTS
A higher likelihood of HADS-identified anxiety and/or depression was associated with significantly lower EQ-5D index and visual analogue scores. Over time, the EQ-5D score rose significantly when the likelihood of an individual representing a HADS-defined anxiety and/or depression case decreased.


CONCLUSIONS
We conclude that the EQ-5D has shown itself to be responsive to differing degrees of HADS-assessed distress, although generalization beyond the UK context requires further investigation.
Whynes
David K
DK
School of Economics, University of Nottingham, Nottingham, UK. david.whynes@nottingham.ac.uk
D000328:Adult; D001007:Anxiety / Q000175:diagnosis*; D003863:Depression / Q000175:diagnosis*; D005260:Female; D006304:Health Status; D006801:Humans; D015337:Multicenter Studies as Topic; D010147:Pain Measurement; D011594:Psychometrics; D011788:Quality of Life; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires / Q000592:standards*; D014626:Vaginal Smears / Q000523:psychology; D055815:Young Adult