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© 1999 American Society for Clinical Oncology Quality-of-Life Measurement in Advanced Cancer: Assessing the IndividualFrom the Department of Psychology, Royal College of Surgeons in Ireland, Our Lady's Hospice, Harold's Cross, and St Luke's Hospital, Rathgar, Dublin, Ireland. Address reprint requests to Dympna Waldron, MD, Medical Research Fellow and Clinical Specialist in Palliative Medicine, Department of Psychology, Royal College of Surgeons in Ireland, Mercer Building, Mercer St Lower, Dublin 2, Ireland; email dwaldron{at}rcsi.ie
PURPOSE: Despite the increasing importance of assessing quality of life (QoL) in patients with advanced cancer, relatively little is known about individual patient's perceptions of the issues contributing to their QoL. The Schedule for the Evaluation of Individual Quality of Life (SEIQoL) and the shorter SEIQoL–Direct Weighting (SEIQoL-DW) assess individualized QoL using a semistructured interview technique. Here we report findings from the first administration of the SEIQoL and SEIQoL-DW to patients with advanced incurable cancer. PATIENTS AND METHODS: QoL was assessed on a single occasion using the SEIQoL and SEIQoL-DW in 80 patients with advanced incurable cancer. RESULTS: All patients were able to complete the SEIQoL-DW, and 78% completed the SEIQoL. Of a possible score of 100, the median QoL global score was as follows: SEIQoL, 61 (range, 24 to 94); SEIQoL-DW, 60.5 (range, 6 to 95). Psychometric data for SEIQoL indicated very high levels of internal consistency (median r = .90) and internal validity (median R2 = 0.88). Patients' judgments of their QoL were unique to the individual. Family concerns were almost universally rated as more important than health, the difference being significant when measured using the SEIQoL-DW (P = .002). CONCLUSION: Patients with advanced incurable cancer were very good judges of their QoL, and many patients rated their QoL as good. Judgments were highly individual, with very high levels of consistency and validity. The primacy given to health in many QoL questionnaires may be questioned in this population. The implications of these findings are discussed with regard to clinical assessment and advance directives.
DESPITE SIGNIFICANT advances in medicine and oncology, most physicians still deal with patients suffering from relentless, incurable illnesses, and decisions are often made about the treatment of terminally ill patients based on judgments about their quality of life (QoL).1-4 QoL is now recognized as an end point of secondary importance only to survival.5 However, relatively little empirical research has been conducted on patients' judgments about what they value in relation to their QoL.6,7 There are both logistical and philosophical difficulties in undertaking such research. One problem is that QoL, which is inherently multidimensional and subjective in nature, does not readily fit into the predominant biomedical model of assessment. In this respect, QoL is similar to suffering, which has been described by Cassel8 as something "experienced by persons, not merely by bodies." Human experience is complex, and knowledge exists at different levels. Kearney9 proposed that the experiences of terminally ill patients should be understood as consisting of a dynamic interweaving of two levels: the surface level, where language is literal, and the deep level, where the mode of knowing is intuitive. Failure by health professionals to understand deeply the complex nature of individual QoL could result in treatment regimens that not only fail to improve QoL but actually contribute to its deterioration. Early attempts to measure QoL in patients with advanced incurable cancer relied heavily on proxy ratings,10,11 the underlying assumption being that those patients would not be able to make such assessments themselves.12 Modern approaches to patient treatment increasingly recognize the importance of subjective patient ratings13-16 and the need to incorporate the views of patients in treatment planning.17 However, there are still fundamental problems with the QoL measures currently used in medicine and oncology.18-22 The dynamic and individual nature of QoL is difficult to capture when using (nomothetic) questionnaires based on grouped data, in which the questions asked, the response format provided, and the relative weights applied to the answers have all been predetermined. Although such measures, which are generally referred to as health-related QoL measures,23 provide important information regarding health status, their promulgation as measures of QoL is more questionable. Calman24 defined QoL in cancer patients as the difference, or the gap, that exists at a particular point in time between the hopes and expectations of the individual and that individual's present experiences. The individual's own view of his or her present reality, hopes, and expectations can only be described by the individual.25,26 Poulson27 urged the medical profession to be "more sensitive in their interactions with patients and to communicate better." Cassel8 emphasized asking the patient for information. Tannock28 highlighted the importance of treating the patient and not just the cancer. Although subjective QoL measures are increasingly replacing objective measures, the content of such measures is still largely predetermined by the investigator. We have previously proposed that a valid QoL measure for patients facing imminent death should permit assessment of QoL from the unique perspective of the individual without imposing a predetermined external value system.6,29 The Schedule for the Evaluation of Individual Quality of Life (SEIQoL) was developed based on the premise that QoL is individual in nature and that a person judges QoL on the basis of how they are doing in a number of salient life areas.25 The definition underpinning the SEIQoL is that a person's QoL is what he or she determines it to be.25,26 The measure was designed to answer three questions: (1) What areas of life (cues) are important to the respondent? (2) How are they currently doing in each of these areas (levels)? and (3) What is the relative importance of each of these areas (weights)?30 Given the complexity of the full SEIQoL, a simpler direct-weighting procedure called the SEIQoL–Direct Weighting (SEIQoL-DW) was developed for use in populations in whom the full SEIQoL might prove impractical.31,32 Because decisions about patients with advanced incurable cancer are often based on judgments about QoL,17,33 this study was designed to determine whether the SEIQoL and SEIQoL-DW are valid, reliable, and acceptable measures of QoL in this patient population.
Participants The sample consisted of 80 consecutive patients with advanced incurable cancer. Forty patients were recruited from a weekly outpatient program held at the Irish National Radiotherapy Centre at St Luke's Hospital in Dublin, and 40 were recruited as inpatients, interviewed between 3 and 7 days after admission to Our Lady's Hospice in Dublin. Only patients who were aware of the terminal nature of their disease and who gave informed consent were included. Patients were excluded if they did not wish to participate or if they were considered by the attending physician in the hospice or hospital to be confused or to be too weak to participate because of imminent death.
QoL Assessment The first stage, cue elicitation, involves determining the five areas of life (cues) considered by the respondent to be central to his or her QoL. These cues are spontaneously generated by the patient. However, if a patient has difficulty generating cues, a short list of examples may be read to him or her. The second stage requires the respondent to rate his or her current status/level of functioning on each cue against a vertical visual analog scale labeled at the upper and lower extremities by the terms "as good as could possibly be" and "as bad as could possibly be," respectively. In the third stage, the relative importance of each cue is determined by using judgment analysis (SEIQoL) or the disk method (SEIQoL-DW). In judgment analysis, the respondent is shown a series of 30 profiles or vignettes and asked to rate, on a visual analog scale, the overall QoL they would imagine they would experience if the profile was their own. Each profile consists of five bars of varying height, similar to the level of functioning bars and labeled with the respondent's own cues. Unknown to the respondent, 10 of the vignettes are repeated to allow estimation of internal reliability of judgments. Multiple regression is used to calculate the judgment policy, which consists of the relative weight the respondent gives to each cue in judging their overall QoL.30 In the SEIQoL-DW, weights are measured by means of a set of disks. This consists of a series of five stacked, centrally mounted, colored interlocking laminated discs with a circular background 100-point scale. The disks can be rotated over each other so that the result is a pie chart consisting of five colored segments. Each segment is labeled using the individual's own cues, and the respondent adjusts the disk until the size of each colored segment corresponds to the weight they attribute to each cue, respectively. The greater the size given to a segment (cue), the greater the relative importance. The disk can be adjusted and readjusted until the individual is satisfied that the result accurately reflects their perception of the relative importance of each cue. In all cases, the SEIQoL-DW was administered first, and then, if the patient was willing and able to proceed, the full SEIQoL was completed.
Outcome Measures and Statistical Methods
Relationship Between SEIQoL and SEIQoL-DW
Study Group Eighty patients were assessed, 40 as hospital outpatients and 40 in the inpatient hospice setting. Patient characteristics are listed in Table 1. In the outpatient population, 14 patients were excluded from the study for the following reasons: (1) they were not aware that their disease treatment was palliative (n = 10); (2) severity of symptoms (n = 1); and (3) refusal to partake in the study because of time constraints to get public transport (n = 3). In the hospice population, 107 patients were excluded from the study because their general state was approaching unconsciousness (n = 88) or because they were confused (n = 19). Of the 88 patients considered to be approaching unconsciousness, 44 (53%) died within 1 week, 64 (77%) within 2 weeks, and 72 (87%) within 3 weeks of admission. In the hospice group, 22 patients (55%) were admitted for terminal care, 13 (33%) for symptom control, and five (13%) for respite. Of the 40 patients interviewed in the hospice, 25 (68%) died within 4 weeks, and 33 (83%) died within 8 weeks of assessment (Table 1). The broad range of tumor types is shown in Table 1. All 80 patients included in the study had extensive advanced local (n = 26; 33%) or metastatic (n = 54; 68%) disease. This was also reflected in the degree of intervention before assessment, with 57 (66%) of the 80 patients having received two or more interventions in the form of surgery and/or radiotherapy and/or chemotherapy (Table 1).
Psychometric Properties of SEIQoL and SEIQoL-DW Global QoL scores. Scores on the two measures were normally distributed based on normal probability plots (SEIQoL, Pearson's r = .995; SEIQoL-DW, r = .992). Of a possible score of 100, the median SEIQoL global QoL score was 61 (mean, 60.4; SD, 17.5; range, 24 to 94), and the median SEIQoL-DW global QoL score was 60.5 (mean, 59; SD, 17.8; range, 6 to 95). Figure 1, with side-by-side box plots comparing median values, shows the variation in QoL scores (SEIQoL and SEIQoL-DW) throughout the patient group. The Pearson correlation between global QoL scores for SEIQoL and SEIQoL-DW was very high (r = .923).
Internal validity and reliability. The median internal validity (R2) score for the 62 patients who completed the SEIQoL was 0.88 (mean, 0.86; SD, 0.076; range, 0.65 to 0.98), and the median internal reliability (r) score was .90 (mean, .87; SD, .10; range, .6 to .95). To date, these are the highest internal validity and reliability results from any application of the SEIQoL (Table 2).
Individual Patient Profiles
SEIQoL-derived data are presented in Fig 2B for a female patient aged 48 years with advanced breast cancer with metastatic abdominal disease in whom third-line chemotherapy was withheld because of severity of symptoms from inoperable intestinal obstruction. The patient nominated remission, life satisfaction, family, marriage, and friends as being the most important areas of life in relation to her QoL. Levels of functioning (on a scale of 0 to 100) indicated that the patient felt she was doing well in relation to family, marriage, and friends and poorly in relation to remission and life satisfaction. Relative weights (on a scale of 0 to 100; five weights constrained to sum to 100) derived from judgment analysis indicated that her marriage and remission were the most important cues, followed by family, friends, and life satisfaction. Of a possible score of 100, her global QoL score ( The patient whose profile is shown in Fig 2A, who was within weeks of death and aware of her likely prognosis, rated her level of functioning of health at 95% and its relative importance compared with other cues at 12%. Family functioning was rated at a level of 47%, and its relative importance was 43%. The patient with similar disease status in Fig 2B nominated the probability of remission as 20%, and its relative importance at 30%. For this patient, remission meant clearance of her symptoms of bowel obstruction. Her subacute bowel obstruction settled with conservative management, and her chemotherapy treatment was recommenced.
Concordance of SEIQoL and SEIQoL-DW
Unique Individual Cue Generation
Individual Weighting of Cues
In this study, two related measures of individual QoL, the SEIQoL and SEIQoL-DW, were used in patients with advanced incurable cancer. The measures were generally acceptable, with all patients being capable of completing the SEIQoL-DW, and 78% of patients being capable of completing the full SEIQoL. One of the apparent limitations of the study was the high number of exclusions in the hospice group. However, this was unavoidable because most of those excluded were judged by the attending physician to be too weak even to carry on a conversation or were semicomatose or comatose and, consequently, were not considered fit to complete any interactive study. The psychometric data indicated that patients were very good judges of their own QoL and that such judgments were consistent. The reliability and validity coefficients were the highest yet found for any application of the SEIQoL. The experience of a serious illness such as cancer and the appreciation of one's impending death seems to heighten awareness about one's QoL and the factors that contribute to it. The individual nature of QoL was reflected in differences in cues elicited, differences in levels of functioning, and differences in the relative importance of each cue to individuals. The high validity scores found for the full SEIQoL indicate that the particular cues chosen were those actually used by patients in judging their overall QoL. Despite increasing sophistication,18-22,39,40 most measures purporting to assess QoL impose external value systems on respondents and usually place the highest priority on health. Health-related QoL measures seek information on functioning in a range of predetermined areas,23 and, in recent questionnaires, the "meaning of life"39,40 is also explored. Health or ill health is essentially the fulcrum around which these measures are developed, and the questions asked depend on the type of disease. In this study, the primacy given to health in many QoL questionnaires was not supported (Fig 4). Deteriorating health does not necessarily result in health becoming the most important factor for these patients. The SEIQoL has good psychometric properties, but it does take a considerable amount of time and effort to complete. In this study, the shorter SEIQoL-DW was found to be a very acceptable measure. It was quick to administer, and all patients were able to complete it. Using the limits of agreement calculation, the differences between global scores generated by the two methods fell within a range of 14.9 (removing outliers, 11.86). Previous experience with the SEIQoL34 and other QoL tools41 indicates that these differences are large in clinical terms and that the procedures are not interchangeable. These findings, and those from a previous study in which healthy subjects were able to identify their SEIQoL-DW judgment policies better than their SEIQoL policies after an interval of 1 week,32 may reflect a fundamental difference between explicit or conscious thought processes and implicit or unconscious thought processes in judging QoL. Conscious thought is directly reportable, and there is evidence that it is a better predictor of behavior when decisions are being made about a person's short-term future.42 Judgment analysis as used in the full SEIQoL may measure unconscious information processing of which the respondent may be unaware, whereas the SEIQoL-DW may deal with explicit information processing. This might explain the differences between the two methods described here. These findings may provide support for the suggestion that life experiences in patients receiving palliative treatment are made up of a dynamic interweaving of two levels: the literal and the intuitive.9 If the relative importance of these cognitive modes were shown to change over time, particularly in the face of impending death, this would have significant implications both for QoL measurement and the predictive validity of advance directives. Physicians seem to be more decisive in making end-of-life decisions than are patients,43 despite the principle that treatment decisions should be based on the values, goals, and preferences of patients.44 These are likely to vary from person to person and to differ from the judgments of physicians. Based on a biomedical model of disease, it is often assumed that QoL invariably deteriorates as death approaches. However, some of the patients in the present study, despite being terminally ill and aware of the nature of their disease, reported good QoL. Little is known about the psychological adaptation and/or response shift45,46 that may occur in patients facing inevitable death. Psychological adaptation may shift the focus of QoL judgments from physical deterioration to social, psychological, and spiritual domains. This adaptation has been described clinically when some patients very near death progress from an agitated state to a calm and accepting state without needing pharmacologic intervention.47 Improving patient QoL is an important goal in health care48,49 and cancer clinical trials50,51 and is the cornerstone for delivery of good palliative medicine.33,52 The increasing recognition of patient autonomy53,54 means that subjective measures will become more important and, in the current climate of evidence-based medicine,55 such measures must be valid and reliable. Nomothetic measures such as health-related QoL questionnaires are important outcomes in cancer care, but in QoL assessment, they should be supplemented with idiographic measures such as the SEIQoL and/or SEIQoL-DW. For practical purposes, the SEIQoL-DW seems more appropriate for routine clinical situations in view of its acceptability, moderate application time, and apparent exploration of explicit (conscious) thought. The SEIQoL seems suitable for more in-depth exploration of QoL. Patients, especially those facing inevitable death, should be asked what they themselves prioritize in their lives. Individual QoL measures may help patients formulate their thoughts for the purposes of making advance directives, agreeing with their care givers on treatment options, and validating proxy judgments, currently much in vogue in relation to end-of-life decisions. Finally, individual measures such as the SEIQoL and the SEIQoL-DW may have a therapeutic application in helping patients make sense of and achieve meaning from the ending of their lives.
Supported by a grant from The Irish Hospice Foundation, Dublin, Ireland. We thank The Irish Hospice Foundation for funding this study, and Dr Ronan Conroy (Department of Epidemiology and Preventive Medicine, Royal College of Surgeons in Ireland) for assistance with the statistical analysis. We also thank the staff of the St Gabriels and St Catherines Wards (Our Lady's Hospice, Harold's Cross, Dublin) and the staff of the Radiotherapy and Oncology Outpatients (St Lukes Hospital, Dublin) for their absolute cooperation with this study.
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Copyright © 1999 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
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ABSTRACT
INTRODUCTION
0.7 is considered acceptable in the context of psychosocial measurement
(levels x weights)); the score can range from 0 to 100, with higher scores representing better QoL. 
) and the SD of the difference (S). If one arbitrarily accepts that differences within 
.0001). The relative weights for these two cues were compared as generated by both QoL measures 
