Objectives: Few generic QoL instruments have been validated in end-of-life (EoL) research or were specifically designed to meet the special requirements of the EoL situation. The conventional global (i.e. single item) QoL question (CQ) is: "How, overall, do you feel?" or a variant thereof, with ratings between e.g. "excellent" and "terrible". An alternative to the CQ is ACSA, in which the respondent defines the anchor points of her own scale of QoL by, after a life review, designating the best and worst periods in her life experience. Current wellbeing is then rated on this idiosyncratic scale. Of note, the life review process is a spontaneous activity of many terminally ill patients, and ACSA emphasises the continuity between past and current life. Our aims were to define ACSA's metric characteristics and to compare ACSA with CQ.
Method: ACSA's metric characteristics were first studied in 43 cancer patients. Twenty patients were followed till the EoL. ACSA and CQ were compared face to face in 2488 general hospital patients suffering from a wide range of psychiatric and somatic diseases.
Results: In cancer patients, ACSA had convergent validity (correlation with several objective QoL indicators) and was reliable (retest). It was well tolerated (60% appreciation) and quite practicable. Compared to CQ it showed higher responsiveness and sensitivity (coefficients of variation 0.69 and 0.41 (pB/.001)). Contrary to CQ, ACSA was not influenced by confounding socio-demographic variables and traits.
Conclusion: ACSA has better metric characteristics than CQ. This may be attributable to its use of an internal standard. It is less concise than CQ, but probably more tactful, empathic, and solemn. The latter features can be hypothesised to better meet some specific requirements of the EoL situation.