A theory-based method for the evaluation of individual quality of life: the SEIQoL.

Few reports about methods of evaluating quality of life (QoL) among the thousands published since medical interest in the subject slowly began nearly 40 years ago are based upon theory. This paper, prepared in response to a request to furnish an exception (Meadows KA. Introduction to an Advanced Seminar: Assessing Health-Related Quality of Life. What can the Cognitive Sciences Contribute? Hull University, October 9, 2000) describes the origins of the Schedule for the Evaluation of Individual Quality of Life (SEIQoL). This derives its cognitive aspects from theoretical studies of perception by Egon Brunswik, their extension to Social Judgment Theory (SJT) by Kenneth Hammond and the application of these ideas to QoL by the present authors and their colleagues.

Randomized, placebo-controlled trial of Chinese herb therapy for HIV-1-infected individuals.

CONTEXT: Alternative medicine or complementary remedies that have not been scientifically tested are nonetheless widely used to treat chronic illnesses, particularly if curative options are limited. OBJECTIVES: To assess the effectiveness of Chinese medicinal herbs in reducing symptoms and improving the quality of life of HIV-infected persons. DESIGN: Prospective, placebo-controlled double-blind study. SETTING: University-based HIV outpatient clinic. PATIENTS: 68 HIV-infected adults with CD4 cell counts <0.5 x 10(9)/L. INTERVENTION: Participants were randomized to receive four daily doses of seven pills containing a standardized preparation of 35 Chinese herbs or placebo for 6 months. MAIN OUTCOME MEASURES: Symptoms, HIV disease progression, HIV-1 RNA plasma viral loads, CD4 and CD8 cell counts, and scores on standard questionnaires for quality of life, depression, anxiety, and coping. RESULTS: Intervention and placebo groups were equivalent at baseline regarding, respectively, previous antiretroviral therapy (74% versus 79%), median CD4 cell counts (0.20 x 10(9)/L versus 0.25 x 10(9)/L), and median HIV-1 plasma viral loads (35,612 copies/ml versus 52,027 copies/ml). At enrollment, none of the study subjects was seriously ill or depressed, and average coping and quality of life scores were in the normal range. In all, 53 (78%) participants completed the study. Patients taking Chinese herbs reported significantly more gastrointestinal disturbances (79% versus 38%; p = .003) than those receiving placebo. No therapy-related toxicities were observed. At completion of the study, no significant differences between the intervention and placebo groups were found regarding plasma viral loads, CD4 cell counts, symptoms, and psychometric parameters. HIV-1 RNA level was unchanged at study end. Among participants who were not on concomitant antiretroviral therapy, median CD4 cell counts declined by 0.05 x 10(9)/L in both the intervention and placebo groups. CONCLUSIONS: This standardized formulation of Chinese herbs for HIV-infected individuals did not improve quality of life, clinical manifestations, plasma virus loads, or CD4 cell counts. The data suggest that this formulation of Chinese herbs is not effective when administered in a Western medicine setting.

Development of a direct weighting procedure for quality of life domains.

The Schedule for the Evaluation of Individual Quality of Life allows individuals to nominate the domains they consider most important to their quality of life and to use their own value system when describing the functional status and relative importance of those domains. The weights for domain importance are derived through a procedure called judgement analysis. As judgement analysis is impractical for individuals with cognitive impairment and in many clinical situations, a shorter, direct weighting procedure has been developed. To test the new procedure, 40 healthy individuals completed both direct and judgement analysis weightings, at t1 and 7-10 days later (t2). After a further 7-10 days (t3), they were asked to identify the weight profiles they had previously produced using each method. The weights produced by the two methods differed on average by 7.8 points at t1 and 7.2 points at t2. The direct weights changed on average by 4.5 points from t1 to t2, while the judgement analysis weights changed by 8.4 points. At t2, 55% of individuals were able to identify the direct weights they had previously produced. The new procedure demonstrates stability and validity but is not interchangeable with judgement analysis. The most appropriate ways of using and interpreting both procedures are discussed.

Illustration of a method for selecting research grant applications.

BACKGROUND: The method used by granting agencies to select applications they wish to support should be explicit, consistent, and fair, especially when the applications are diverse and controversial in nature, or when funds are limited, which is often the case. This study demonstrates the use of a method to satisfy such standards. METHODS: An expert committee appointed by the Swiss National Research Foundation planned and advertised a program for the evaluation of alternative therapies. The selection of applications to be supported was assisted by the use of Judgement Analysis. In the first phase, appropriate standards such as relevance to the program objectives and methodological adequacy were established. In the second phase, the relative weights attached to these standards by individual members were obtained by multiple linear regression analysis. In the third phase, a single common policy based on the standards that had been made explicit was applied to the choice of projects to be supported. RESULTS: 219 grant applications that proposed a variety of alternative treatments for various indications were reviewed; 17 were funded. CONCLUSIONS: The method of Judgment Analysis was acceptable to the experts, who were drawn from several disciplines and had diverse points of view. The method proved understandable and easy to use.

Use, misuse and abuse of questionnaires on quality of life.

Questionnaires quantify formal aspects of unidirectional communication. This definition indicates the major limitations of research based on such techniques: it will be unbalanced and restrictive, and therefore incomplete. The wide use of questionnaires is often unavoidable in medical and scientific research, yet they are often developed with insufficient attention to the needs that they are intended to meet. Their design may be imperfect even in relatively straightforward circumstances such as the reporting of laboratory observations, but inappropriate as well as imperfect in others, such as the study of individual quality of life. This concept and others related to it are defined, together with some major sources of error in questionnaire development and use. Steps that can be taken to improve the situation are also mentioned.

How can we measure individual quality of life?

Quality of life is widely discussed today as an important outcome variable in health care. The scientific interest focussing during most of the 20th century on illness enlarges its scope and includes well-being as an important goal and concept. Hence, quality of life (QoL) as a measure of well-being was included in many studies, but mostly determined by the purpose of the study and the external investigators. In order to weigh subjective needs and desires adequately, the Schedule for Evaluation of Individual Quality of Life (SEIQoL) was developed. This analysis is obtained from parameters chosen by the explored subject or patient himself. With the help of structured questions, the relevant dimensions of well-being for a given person are identified and put into context to the actually experienced situation. This method allows the sensitive detection of changes over time, and as a consequence of changes in life circumstances. It goes beyond the simple determination of health status and rather reflects the current state of the person as a whole.

Individual quality of life in the healthy elderly.

Quality of life research with the elderly has usually focused on the impact of decline in function, and used a pre-determined model of quality of life in old age. The Schedule for the Evaluation of Individual Quality of Life (SEIQoL) allows individuals to nominate, weigh and assess those domains of greatest relevance to their quality of life. The SEIQoL was administered to 56 healthy elderly community residents at baseline and 12 months later. Quality of life levels were significantly higher at baseline (t = -2.04; p = 0.04) than that of a previously studied sample of healthy adults below 65 years of age, and did not change significantly over the study period. The domains nominated by both samples as relevant to their quality of life differed notably. Health status was not correlated with the perceived importance of health at baseline, and showed only a low correlation (r = 0.27) at 12 months. The weight placed on health did not increase over the study period despite a significant decline in health status. The value of allowing the individual to define personal quality of life values in a research context is explored.

Quality of life after the menopause: influence of hormonal replacement therapy.

OBJECTIVE: Our purpose was to demonstrate the clinical efficacy and effect of hormone replacement therapy in menopause on quality of life. STUDY DESIGN: A randomized, open, 6-month comparison of hormone replacement therapy (estradiol transdermal system [Estraderm TTS] plus chlormadinone) and symptomatic treatment (verapipride) was performed. Analysis was by intention to treat. RESULTS: In 499 postmenopausal women with moderate and severe symptoms enrolled by 101 physicians, hormone replacement therapy was superior to symptomatic treatment on all assessments of quality of life and clinical efficacy. The effects were independent of the incidence of hot flushes. CONCLUSION: The effect of hormone replacement therapy on the quality of life of postmenopausal women was significantly superior to symptomatic treatment.

Health status and quality of life: which matters to the patient?

The effect of treatment on the health status of patients suffering from claudication of the lower limbs has seldom been studied, and their quality of life (QOL) not at all. These terms are distinguished and defined. Studies of both are important, but it is believed that QOL is of more interest to the patient, as representing the individual's appreciation of and reaction to factors of personal importance. The many methods employed can be classified according to (a) their emphasis on the individual as against the group and (b) their attention to internal as against external variables. Problems met in creating new methods for the study of QOL are discussed. These include eliciting features of their condition that are of specific importance to patients, and establishing the different degrees of importance that individuals attach to these. The new instrument must be phrased in an acceptable, reliable, and valid form for subsequent use. Its validity is most convincingly demonstrated by the ability to discriminate between patients with different degrees of disease severity or those who have been differently treated, as in a clinical trial. Comparative advantages of general and specific methods of inquiry, results expressed as profiles or single indicators, and the influence of contextual factors (bias due to timing, the effect of the investigator-subject relationship, etc.) are also discussed.

Individual quality of life in patients undergoing hip replacement.

Quality of life (QoL) assessment is becoming increasingly important for measuring the impact of illnesses, diseases, and their treatment and for deciding priorities when allocating resources. We developed a novel method to measure QoL from the perspective of the individual patient. The schedule for the evaluation of individual quality of life (SEIQoL) was devised from the technique known as judgment analysis to measure patients' level of functioning in five self-nominated facets of life and the relative weight or importance attached to these areas. We applied this method, together with traditional measures of health status, in a prospective intervention study of 20 patients undergoing unilateral total hip-replacement surgery with six-month follow-up by comparison with matched, non-patient controls. Health status was significantly improved by hip replacement on the McMaster health index questionnaire (p less than 0.001) and the arthritis impact measurement scales (p less than 0.001). Individually measured QoL was significantly increased after surgery when measured by SEIQoL (p less than 0.02). The individual nature of QoL was reflected in the variety of life areas nominated as important by individual patients, the differences in relative weights attached to these areas, and the complex nature of the changes that occurred postoperatively. Our data not only highlight such individuality but also show that SEIQoL provides a means by which this can be assessed scientifically.

Assessing the quality of life of the individual: the SEIQoL with a healthy and a gastroenterology unit population.

Current methods of measuring quality of life (QoL) impose an external value system on individuals, rather than allowing them to describe their lives in terms of those factors which they consider important. The Schedule for the Evaluation of Individual Quality of Life (SEIQoL) was developed to overcome such limitations. The QoL of 42 healthy attenders at an international immunization clinic was assessed using SEIQoL. Judgement reliability was high (r = 0.74) and individuals' judgement policies accounted for a large percentage of the variance in overall QoL (R2 = 0.75) demonstrating the construct validity of judgement analysis in this context. In a second study of QoL of out-patient suffering from irritable bowel syndrome (IBS) (N = 20) or peptic ulcer disease (PUD) (N = 20) was assessed using SEIQoL. Judgement reliability was lower (r = 0.54) although statistically highly significant (P less than 0.01), and the variance in overall QoL judgements explained was high (R2 = 0.74). SEIQoL is an acceptable, reliable and valid technique for measuring individual QoL that takes greater account of individual perspectives than traditional measurement approaches.

Clinical judgment analysis.

Judgement is central to the practice of medicine and occurs between making clinical observations and taking clinical decisions. Clinical judgment analysis has developed as a method of making statistically firm models of doctors' judgments. Computed models reveal the differential importance attached to items of clinical, social, or other data which are determinants of clinical decisions. These models can both reveal the causes of conflicts of judgment and may help resolve them in a way that unaided discussion cannot. Revealing experts' models to students speeds learning of diagnostic skills. Clinical judgment analysis offers a method of probing the judgments not just of students and doctors but also of patients who have shown systematic differences in their perceptions of risk and benefit. The power and relevance of clinical trials can be improved by the consistent application of judgment policies generated from both the trialists and those who will use their results.

Increasing the power of clinical trials through judgment analysis.

A method for increasing the statistical power of clinical trials to detect clinically important differences is described. Inconsistency in physicians' overall judgments of treatment effectiveness adds "noise" to a trial that may mask either the superiority or the inferiority of particular treatments. The method described here uses "judgment analysis" to reduce errors in an individual's overall judgments of treatment effectiveness. The method can also be used to reduce error variance due to differences in judgment between physicians and may thus be particularly useful in multicenter trials. The method is illustrated with results from a recent trial.

Experiments on clinical observation and judgement in the assessment of depression: profiled videotapes and Judgement Analysis.

Variations within and between observer-judges reduce the accuracy of clinical research. Judgement Analysis allows strategies to be developed and applied which reduce variation in judgement. The prediction that the removal of important sources of error variance by this means would reduce the likelihood of committing a Type 2 Error was supported by the application of Judgement Analysis to assessments by 15 psychiatrists of 92 patients in a clinical trial of 2 antidepressive treatments. The statistical significance of differences between the effect of the treatments on the severity of depression was increased, and significant differences appeared earlier. Ten stimulated patient profiles were also converted into narrative case histories, enacted by experienced psychiatrists or psychologists and videotaped. The participants' judgements of the overall severity of the depression were in good agreement with those they had made on the original cases. Videotapes so prepared help training to reduce variation in observation, just as Judgement Analysis can lead to reductions in the variation of judgement.

Inability of rheumatologists to describe their true policies for assessing rheumatoid arthritis.

Eighty nine British and Australian rheumatologists took part in a study to discover how accurately they could describe their procedures for measuring disease severity in rheumatoid arthritis. The relative importance they attached to different clinical and laboratory variables showed a very wide variation, and these stated policies were generally poor at predicting their actual judgments when assessing 'paper patients' (r2 = 39%). Policies based on equal weighting of all variables, while also poor predictors (r2 = 41%), were nevertheless superior to their stated policies for 49 respondents. Policies calculated by judgment (linear regression) analysis were much more successful predictors (R2 = 73%). Unhurried, detailed interviews with four experienced rheumatologists provided carefully considered statements of assessment policy, but these also were poor predictors of routine assessments of outpatients (r2 = 34%) compared with policies calculated by clinical judgment analysis, even when these were applied to new data (R2 = 88%).