Cancer patients quality of life, measured by themselves and proxys.

Abstract

Health Related Quality of Life (HRQoL) is an essential factor for cancer patients, particularly in the evaluation of the care's. Most of the information that health care providers have is given by the patient. Family can also provide information about them, appealed or not and the quality of such information isn't studied for Portuguese population. The aim of this study was to examine whether proxies can provide useful information on HRQoL of cancer patients.We studied a sample of 176 ambulatory cancer patients and those 176 respective proxies (family) from Medical Oncology Department. A sociodemographic characterization was made for the simple and a clinical characterization was made only for cancer patients. To measure HRQoL were used the EORTC QLQ-C30. Beyond descriptive techniques, the statistical analysis was done using Interclass Correlation (ICC) and Pearson Correlation (r).We found moderate to good agreement (ICC ranged from 0.55 to 0.82, as well as the Pearson correlation) between responses from patients and those from their proxies for the QLQ-C30 scales. Proxies' group considered patients as having higher degree of fatigue, pain and diarrhea and a more impaired physical and emotional functioning, worse global QoL and total score. Statistically significant differences between patients' and proxies' evaluations were found for these subscales. None of the patients or proxies characteristics showed any relationship with the agreement between patient and proxy QoL evaluations'.The results suggest that proxies only provide valid and useful information about cancer patients QoL for QLQ-C30 domains where the agreement between QoL's responses were high and the means diferrence not significant. For using a HRQoL instrument taking into account as source the proxy, is necessary to recognize the agreement of the HRQoL's domains of the instrument. In this case, for several domains of QLQ-C30 the means difference was statistically significant, so, the instrument should be used with caution for physical and emotional functioning, global QoL fatigue, pain, diarrhoea and total QoL. Proxies are a frequent and a mandatory source of information about patient's status, particularly in palliative care. On a clinical point of view, the knowledge of these differences is very important for that such information be ponderous and contextualized in order to improve better care to the patients.