Adding the most significant chord to the song

Summary. Background: This article provides an overview of studies in which assessments of specific functional capacity, made by experts on the one hand (objective) and by patients on the other (subjective) were compared in various patient groups. In essence, these data reveal marginal or insignificant associations. Methods: Based on these considerations, a theoretical differential-diagnosis model of objective findings/subjective state of health is presented. By dichotomization of specific functional capacity at these two levels, the model permits the classification of a patient cohort into four sub-groups: Patients with concurrence between subjective and objective assessments are referred to as “the fortunate” while those with a negative concurrence are termed “the unfortunate”. In case of discrepancies between these two levels, for instance when patients’ subjective assessment was good although their condition was obviously poor, they are considered to be in a so-called “disease paradox”. Alternatively, patients whose subjective assessment of their condition was poor although the objective findings were positive, were considered to be in a so-called “health dilemma”.

Results: The study in a sample of patients who had received an artificial hip joint for mobility disorders revealed striking differences in health-related quality of life (HrQol). Comparisons of HrQoL data pre- and post-operatively in the whole sample demonstrated an improvement in five of six dimensions (loss of energy, pain, emotional reaction, sleeping problems, and problems in physical mobility, p<0.01) of the Nottingham Health Profile. Specifically, after grouping patients accordingly to the proposed model striking positive changes in HrQoL were registered in patients of the fortunate and disease paradox groups while the improvements in the health dilemma and unfortunate groups were minimal.

Conclusion: Timely identification of these patients in the process of rehabilitation would significantly contribute to the achievement of a good health-related quality of life for all patients.

Key words: Health-related quality of life, Nottingham Health Profile, functional capacity, total hip arthroplasty

Introduction

One of the first researchers who focused on this point of intersection between medicine and clinical psychology and conducted a specific and comprehensive study of the discrepancies between the judgments of medical experts and those of patients in respect of their state of health was Myrtek (1998). In his theory of illness behavior, Myrtek described a scheme of four categories consisting of two congruent groups which he named healthy and ill persons in the medical sense. Apart from these, he identified two discrepant groups which he assigned “inappropriate illness behavior” (in 1978 Pilowsky had termed this phenomenon “abnormal illness behavior”). Depending on their inclination, he named these groups “healthy ill persons” or “ill healthy persons”, as evidenced by the title of his book.

A few years earlier, in 1991, Filipp and Ferring had made a similar formal classification, a division into four categories. In their description of subjectivity and objectivity in the determination of quality of life, they also distinguished between four groups: In case of concurrence of subjective and objective evaluations of quality of life they referred to the persons as “the fortunate”; in case of negative concurrence the authors referred to the individuals as “the unfortunate”. In case of discrepancies between these two levels, for instance when the individuals’ subjective assessment was good although their objective state was evidently poor, these persons were considered to be in a paradox situation, i.e. in a “satisfaction paradox”. Alternatively, the individuals were deemed to be in a “dissatisfaction dilemma” when their subjective assessment of their condition was poor despite the presence of positive environmental factors (Figure 1).

illustration not visible in this excerpt

Figure 1. Original scheme of Filipp and Ferring (1991) describing general quality of life.

These concepts were demonstrated by results from practical experience, based on a psychological study of Brickman, Coates and Janoff-Bulman (1978). The authors requested three groups of test persons to asses their state of happiness, i.e. their subjective state. The first group consisted of lottery winners, the second of patients who had suddenly been confronted with the diagnosis of paraplegia following a life- threatening accident, and the third was a control group. An evaluation of the assessments of their current status revealed that the patients’ subjective state was - as expected - highly significantly poorer than that of the control group. However, it was striking to note that the subjective state of lottery millionaires, apparently favored by fortune, was hardly better than that of the control group. The probands’ prognostic assessments of their state of health at a fictitious time-point in the near future (about one year) were entirely unexpected for the layman: Despite extremely diverse external environmental factors, the three groups gave nearly identical estimates of their future subjective states.

Discrepancies between objective findings and subjective state of health in the health sector Accordingly, several studies have shown that associations between doctors’ estimations of health-related stresses and the corresponding evaluations of patients remain insignificant. In a large preventive study focusing on cardiovascular disease in middle-aged men, Robra, van der Heyden and Machens (1982) observed pathologically elevated cholesterol and blood sugar levels in 20.7% and 12.0%, respectively. Smoking and obesity are known to be major risk factors for cardiovascular disease. However, if one considers the medical history and the state- of-health data of the high-risk group, persons deemed to be at great risk reported milder symptoms than did persons with no risk factors. The agreement between the doctors’ estimations of the health status of middle-aged women and the women’s own evaluations was reported to be 22% by a Swedish group; the authors considered this value significant but low. Correlative associations between individual symptoms and the estimations explained only 1 to 12% of the underlying variance (Mellner & Lundberg, 2003). Similarly, objective stress values in a healthy population showed only moderate agreement with the corresponding assessments obtained by questionnaires (Lindholm, Brevinge, Bergh, Körner & Lundholm, 2003). This phenomenon is observed in patients with physical disease as well: In a randomized group of patients with different somatic diagnoses, Mabe, Hobson, Jones and Jarvis (1988) requested the treating physicians to assess the severity of symptoms on a seven-point Likert scale. A comparison of these assessments with those of patients revealed a non-significant correlation value of 0.10; a large majority of the patients over-estimated the severity of their symptoms. Michel, Kohlmann and Raspe (1997) established a moderate agreement (kappa = 0.47) between the treating physicians and the patients in respect of the severity of symptoms in a specific patient group (back pain). Filipp and Ferring (1991) report an insignificant correlation coefficient of r = 0.17 in a random sample of gastroenterological patients.

Confirmation of the presence of a wide discrepancy between the objective and the subjective state of health reported by patients, and the theoretical models proposed for this phenomenon in the published literature, will be investigated here in order to answer the following question: Is it possible to identify the above mentioned four groups on the basis of the clinical condition (specific functional capacity) of patients in the process of rehabilitation within a precisely defined cohort?

Explanation of terms

For the following study the above mentioned theoretical models were used and modified as follows: The modified Viennese model was based on one variable that is accessible to objective as well as subjective assessment, namely the so-called specific functional capacity. What does “specific” functional capacity here mean; in what way does it differ from a “general” functional capacity that may be present? Owing to the Babylonian confusion of terms, which is frequently mentioned in the literature (Leplege & Hunt, 1997) - Tully and Cantrill (1999) call it the “semantic minefield” - a digression is given here, which delineates the medical and psychological constructs used in this study.

The extent of “health-related quality of life” as determined by the patients was selected as the outcome variable because, on the one hand, one of the goals of rehabilitation is to improve the patient’s quality of life (Richter, Schwarz, Eisemann & Bauer, 2003; WHOQoL Group, 1995) and, on the other hand, quality of life is considered to be a dynamic construct that may change in the course of time, e.g. when a critical event in life occurs or the patient undergoes a severe type of medical treatment (Allison, Locker & Feine, 1997). The term quality of life actually originated in the social sciences. It was coined in welfare economics in the beginning of the 20th century. Quality of life achieved socio-political significance, especially in the USA, from the mid-sixties of the last century. It entered Europe somewhat later, where it was offered as an alternative to counter the pre-eminence of purely quantitative thought. In other words, purely economical indices were complemented by social factors. In the health sector, the concept of quality of life research, i.e. the concept of health-related quality of life became established only in the beginning of the nineteen-eighties. Although one would presume that a subject like health-related quality of life of patients should be of major importance in this sector, i.e. for medical specialists, psychologists and health-care personnel, a scientific discussion about the theory and measurement of this construct started rather late. After individual survey instruments had been constructed and tested in practice, the last few years have witnessed a revival, a kind of retrospective look at the theoretical and methodological principles of quality of life research, coupled with considerations as to how such research can be systematically integrated in the evaluation, quality assurance and planning of future health care services (Bullinger, Ravens-Sieberer & Siegrist, 2000). The reason is to be found in the indeterminateness and poor tangibility which persisted for a long time around this construct. Quality of life is a construct that is considered familiar by many because of its practical context, but has not been scientifically defined until the present day. The importance of health-related quality of life clearly lies in the fact that it has made a significant contribution to a transformation - farther away from a purely mechanistic-physiological view of the anonymous patient, and closer to a holistic appraisal of the individual. The main points of focus of this concept are the individual, his/her thoughts and feelings, state of health, and ability to cope with the disease (Rosenberg, 1995). Despite the absence of a comprehensive and widely accepted definition, experts agree that health-related quality of life must be regarded as a multi-dimensional construct consisting of the following main components (Bullinger & Hasford, 1991):

[...]