On the receiving end--III. Measurement of quality of life during cancer chemotherapy.

From previous studies of the side effects patients identified as important in cancer chemotherapy we identified eight groups of symptoms. Linear analogue self assessment (LASA) scales for these 8 items form a new instrument (GLQ-8) for measuring aspects of quality of life. Patients completed both GLQ-8 and five previously validated LASA scales, together with a new single global quality of life scale (GLQ uniscale) and the visual analogue version of the Spitzer QL Index. This analysis includes 166 patients, with 47 1-hr test-retest and 29 24-hr test-retest pairs. The new scales showed high reliability, with retest correlation coefficients exceeding 0.8 for all items except GLQ uniscale, appetite and anxiety on 1-hour retest, and all except nausea and numbness on 24-hour retest. Correlations were in general higher for the GLQ-8 items than for the 5 older LASA items, while inter-item correlations were lower. Comparisons of the new scales with established instruments and comparisons of new scale scores between known groups supported the validity of the new scales. We conclude that the GLQ-8 and GLQ uniscale are convenient and reliable instruments measuring aspects of quality of life in patients receiving cancer chemotherapy.