- In the absence of a quality of life instrument which is applicable to the caregivers of elderly relatives and amenable to a cost-utility analyses, the Caregiver Quality of Life Instrument (CQLI) was developed using Torrance's time trade-off technique. The CQLI was administered to 30 family caregivers and 10 relatives of well elderly. Utility scores were obtained for three standardized caregiver situations and the subject's own state. The CQLI could be completed by almost all subjects. Good test-retest reliability was established. The subjects were able to discriminate between degrees of caregiver wellbeing using standardized states and the CQLI scores discriminated among groups of subjects. The CQLI detected within-subject change in caregivers whose relatives received institutional respite care. The CQLI appears to be feasible, reliable, valid, and responsive to change. Further CQLI applications and research are recommended.