Assessing health-related quality of life in palliative care: Comparing patient and physician assessments

Abstract

It is often difficult to recruit patients for palliative care studies and severe attrition must be expected resulting in biased findings. This may be avoided if equivalent information could be obtained from sources other than the patients. Therefore, we investigated whether physician assessments can be used to evaluate the patients’ health-related quality of life (HRQOL). Patient and physician assessments of the patients’ HRQOL were obtained once a week for up to 13 weeks using EORTC QLQ-C30 items. The agreement between patients and physicians at first contact (N = 115) and for the following 13 weeks combined (total N = 263) was investigated. Significant differences between patient and physician assessments were observed for all HRQOL domains assessed. Physicians reported patients to have fewer problems/symptoms than patients did for all HRQOL domains except for physical and social functioning. The agreement between patients and physicians was poor. Using physician assessments may bias findings and cannot be recommended as a substitute for patient self-assessment in palliative care.

Introduction

Palliative care aims at providing the best possible care to improve the quality of life of patients and their families.¹ To achieve this goal, it is necessary to evaluate the effect of the care. However, it is often difficult to recruit patients for palliative care studies and severe attrition due to deterioration must be expected.2, 3 This biases results and limits the broad applicability of findings.⁴ If equivalent information could be obtained from other sources than the patients, this would be preferable in descriptive studies in palliative settings. This could potentially improve the generalizability and the range of descriptive studies ethically and practically feasible in palliative care. Such alternative sources or ‘proxies’ could be physicians, nurses, or significant others.

There is general agreement that the patient is the most appropriate source of information regarding his/her quality of life. Therefore, proxy assessments should only be used if in agreement with the patients’ own ratings. Several studies have compared patient and proxy ratings in general. A review from 1992 concluded that the concordance between patient and proxy ratings was far from optimal.⁵ The ‘up-date’ from 2002 was more positive, concluding that proxy ratings are reasonably accurate and substantial discrepancies occur in a minority of cases only.⁶ However, it was noted that proxies tended to overestimate the patients’ problems and symptoms.⁶ A number of studies have compared the responses of terminally ill/palliative care patients with proxy responses7, 8, 9, 10, 11, 12, 13, 14, 15, 16 (see Ref. [17] for a review). Except for one, these studies were small (less than 50 participants8, 9, 13, 15) or of moderate size (less than 80 participants10, 11, 12, 14, 16). The agreement ranged from poor to good agreement across the studies with a tendency to better agreement for concrete and overt symptoms, such as impaired physical functioning, vomiting, and dyspnoea, while poorer agreement often was observed for subjective aspects such as emotional functioning, feelings, and pain.

The majority of proxy studies in palliative care have evaluated the use of family caretakers/significant others as proxies. Some significant others may be too emotionally affected by their relative’s condition to be able and willing to participate as proxies. The health care professionals, e.g. the physicians, could in principle provide information about all patients regardless of the patients’ conditions. Ratings of the patients could be incorporated into the physicians’ daily rounds. We have only identified two studies comparing responses from the professional staff and patients,7, 16 and one of these studies evaluated the agreement on one overall quality of life measure only.¹⁶ Both studies found relatively poor agreement and recommended that staff ratings be avoided or used with caution. In light of the clear advantages of using staff ratings in palliative care, further evidence is needed to determine whether the agreement is sufficient or staff ratings should be avoided. Therefore, we initiated a study investigating whether ratings from physicians in a palliative care unit could replace patient ratings. The aim was to evaluate the agreement between physicians’ and patients’ ratings of different aspects of the patients’ health-related quality of life.