Development and validation of a short measure of health status for individuals with amyotrophic lateral sclerosis/motor neurone disease: the ALSAQ-40

In recent years there has been an increased appreciation of the importance of measuring health status from the patient's point of view, but until now no attempt has been made to develop an amyotrophic lateral sclerosis (ALS)- specific health status measure. The development of such an instrument is es pecially relevant now with the introduction of drugs that prolong life in A LS but limited data is available on the impact such treatments have on qual ity of life. This paper reports on the development of an ALS-specific measu re, the forty item ALS assessment questionnaire (ALSAQ-40). The development of the ALSAQ-40 followed three main stages. Stage 1 consisted of in-depth, semi-structured exploratory interviews conducted on a sample of 18 patient s to identify areas of salience and concern to patients with ALS. These int erviews generated 78 candidate questions. In stage 2, the 78-item questionn aire was used in a postal survey to identify appropriate rephrasing/shorten ing and to determine the acceptability of the measure. In addition, this ex ercise helped identify sub-scales of the instrument addressing different di mensions of ALS. Finally in stage 3 the data collected in stage 2 was analy sed to areas measured by the instrument and to remove redundant questions. The resulting measure contains forty questions measuring five areas of heal th status: Eating and Drinking, Communication, ADL/independence, Physical m obility, Emotional Functioning. The measure has high face, internal and con struct validity and is likely to prove a useful measure in the evaluation o f treatment regimes for ALS/MND.