How to assess quality of life? Aspects of methodology

How to assess quality of life? Aspects of methodology

International Congress Series 1229 (2002) 31 – 37 How to assess quality of life? Aspects of methodology Elizabeth M. Alder * Faculty of Health and Li...

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International Congress Series 1229 (2002) 31 – 37

How to assess quality of life? Aspects of methodology Elizabeth M. Alder * Faculty of Health and Life Sciences, Napier University, Edinburgh, UK

Abstract There are many different ways of assessing quality of life in the menopause, and there are different meanings of the term ‘menopause’ and of ‘quality of life’. Menopause is a time of physical and psychological changes, and has been associated with a larger and varied number of symptoms. Menopause is a transition and differs from illness. Self identity may be determined by age related changes, illness cognitions and symptom attributions. These need to be taken into account when assessing changes that affect quality of life during the menopausal transition. Early work concentrated on so-called menopausal symptoms and variations of the Blatt Kupperman Menopausal index were widely used. However, the symptoms were highly selected, the scales had no psychometric properties and they were derived from biased samples. They have been replaced by standardized scales that have reported properties of reliability and validity. Measurement of quality of life can be made on the basis of an agreed set of judgements from experts or lay people, or by a person-centered approach from individuals themselves. There are important implications for studies of research in the menopause using different theoretically based measurements of quality of life. D 2002 Elsevier Science B.V. All rights reserved. Keywords: Menopause; Quality of life; Measurement

1. Introduction There are many different ways of assessing quality of life in the menopause. They are very different, partly because understanding of the meaning of Quality of Life and partly because of the different interpretations of the term menopause. These two issues will be discussed before going on to consider the context of menopause and methodological issues. *

Tel.: +44-0131-536-8606; fax: +44-0131-536-5624. E-mail address: [email protected] ( E.M. Alder).

0531-5131/02 D 2002 Elsevier Science B.V. All rights reserved. PII: S 0 5 3 1 - 5 1 3 1 ( 0 1 ) 0 0 4 7 3 - 3

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2. Meaning of quality of life Quality of life may be seen positively in terms of life satisfaction and feelings of wellbeing, and goals and expectations that have been achieved. It can also be seen as reflecting symptom severity, level of impairment or handicap, and reflecting loss. Quality of life can be described in terms of subjective well-being (does your health interfere with your social life?) or functional status (can you dress unaided?). Therefore, quality of life in the menopause can be measured in terms of symptoms, personal experience or functional ability.

3. Meaning of menopause The menopause is usually defined as the cessation of monthly periods and may be defined as having occurred when there has been a year since the last menstruation. The term climacteric is wider and usually applied to the transition between the pre and menopausal state. Women may be pre menopausal with regular cycles, peri menopausal when menstrual cycles become irregular or post menopausal when menstrual cycles have ceased.

Table 1 Symptoms associated with the menopause Aching or sore joints, muscles and tendons Anxiety, feeling ill at ease Bouts of rapid heart beat Breast tenderness Changes in body odor Depression Dizziness, light-headedness, episodes of loss of balance Dry vagina Electric shock sensation under the skin and in the head Exacerbation of existing conditions Fatigue Flooding; phantom periods, shorter cycles, longer cycles Gastrointestinal distress, indigestion, flatulence, gas pain, nausea Hair loss or thinning, on head, pubic, or whole body; increase in facial hair Headache change: increase or decrease Hot flushes, flushes, night sweats and/or cold flashes, clammy feeling. Increase in allergies Increased tension in muscles Irregular periods; shorter, lighter periods; heavier periods, Irritability Itchy crawly skin Loss of libido Mood swings, sudden tears Sudden bouts of bloat Tingling in the extremities Weight gain

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The menopause is a time of physical symptoms and health changes. There may be direct effects of endocrine changes on health conditions such as cardiovascular disease or indirectly on sexual function as part of the ageing process. Osteoporosis in women is clearly related to a decline in oestrogen levels and there is a well-established relationship between bone mineral density and fractures. Cognitive changes, especially those associated with memory loss, cause concern and anxiety in older women. There have been suggestions that oestrogens and androgens whose levels decline with age, influence cognitive functioning. The menopause is often associated with specific symptoms and it has been regarded as an endocrine deficiency disease, although another perspective is that menopause is a socially constructed concept [1]. Some examples of symptoms associated with the menopause are shown in Table 1.

4. The menopausal transition The whole process of transition from pre menopause to post menopause may take over 10 years. These 10 years, which may occur any time from 40 to nearly 60, are also times of life changes and considerable psychological changes. There are changes in role and the woman become less concerned with parenting her own children and may become more focussed on her career and may also have elderly parents that need care. Grandchildren may make more demands but also become a source of pleasure and satisfaction. There are social and psychological consequences of fractures in old age and consequent loss of mobility and independence, which directly affect quality of life. Menopause is not a simple illness, and the illness model may be inappropriate for a psychosocial transition. Menopause may be regarded as an illness because of expectations of age-related changes, and because of beliefs about illness and of attributions of symptoms. These are related to self identity. Illness is usually recognised because of the presence of symptoms. Unusual symptoms which are severe enough and last long enough lead people to feel that they are ill and they behave in certain ways—like complaining. People vary in their ability to report physiological states such as heart rate, and some people will be more accurate in reporting hot flushes than others. Not all symptoms will be reported and not all to all people. Hot flushes may be perceived as part of a natural pattern of ageing or as a symptom that requires medical attention. The way in which these affect quality of life may lead some women to consult physicians but others to ignore them. Mechanic [2] suggested a number of factors that influence symptom reporting. The perception of symptoms may bear little relation to the medical opinion of severity, as has been found with women’s estimates of menstrual blood loss [3]. The extent of the social and physical disability resulting from the symptoms may determine their perception and attribution. A headache may or may not interfere with social activities. Hot flushes and night sweats in menopausal women may be perceived as normal, yet in some cases they cause severe social distress. The recognition and identification of the symptom will depend on the cognitive schemata that the patient has of the symptom. Increased knowledge may help women to recognise there is a physiological change taking place, but may also medicalise the symptoms. The perceived severity of the symptoms may be related to a

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threshold or to a change. A sudden increase in urinary frequency, a weight increase, changes in the skin or an increase in frequency of headaches may be seen as symptoms. There are many cultural and demographic influences on health and these affect its perceived relationship with quality of life. Poor health may be an accepted part of living in some deprived areas and affluence may bring increased expectations of health. Although more illness is found in community surveys in lower socio-economic groups, people in higher socio-economic groups are more likely to seek health care. Older people consult their doctors less often than younger people in relation to their level of illness [4]. In trying to understand the relationship between the endocrinological event that is the menopause, and the quality of life, we need to know how women interpret physiological and psychological changes. We are constantly seeking the meaning of events. The changes may be explicable in terms of the medical model and have a clear physiological aetiology and consequent treatment. However, menopausal symptoms include many less clearly defined and psychological symptoms. These may be attributed to the physical changes, e.g. hot flushes, or may be seen as symptomatic of the menopause itself. Symptoms on their own have no meaning and are merely bodily sensations. Different symptoms will be accounted for in different ways. A backache may be attributed to pre-menstrual syndrome, or old age depending on the personal circumstances. Symptoms are not static and their pattern may contribute to the search for meaning. Leventhal and Benyamini [5] suggest that there is asymmetrical relationship between symptom and the diagnostic label. People with symptoms seek a diagnostic label. Thus, if they have changes in mood or wellbeing, they will be reassured that they are experiencing the menopause. People given a diagnosis may seek symptoms so that if they are aware that there is a syndrome called the menopause, they may be alerted to symptoms.

5. Measurement in the menopause It is relatively easy to measure menopausal symptoms and there are a number of possible measures. The Kupperman Menopausal index was developed in the 1950s and was widely used in many research studies in Europe and the USA [6]. The original index was derived from Kupperman’s clinical experience in New York in the 1950s, but it lacks the properties of scales that are used today in evidence-based medicine [7]. The index combines self report and physician ratings; but it does not include any measures of vaginal dryness and loss of libido, thus lacking content validity. The original publications gave no demographic data of the sample and weighting was used without statistical justification. The terms were ill-defined and many of them are archaic. The categories included overlapping scores, and most importantly, scores were summed without being based on independent factors [8]. Since the original publications many research studies have used modified versions, but they have not been validated Modern psychometrics has led to the publication of reliable and valid scales that can be used in research. A scale is based on a defined populations and it is important to know whether it is a community or a clinic sample. Self reports are considered more valid and reliable than physician ratings. The language may influence reporting and there may be differences between British English and American English. A scale of meno-

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pausal symptoms should be based on factor analysis which allows subscales to be produced. Modern scales have properties of reliability, the extent to which the scale is consistent, or effective. This is usually measured by test and retest reliability. The tests are given on two separate occasions and high correlations are expected. Internal reliability is usually measured by Cronbach’s alpha. Alphas below 5.00 suggest that the items are not tapping into the same area. For example, mood items should relate to each other but might be different from mobility. If there is high agreement between items, e.g. over 9.00, then it probably means that they are measuring the same thing. A scale can be very reliable but it is only useful if it is also valid. Validity is an essential property of scales and is the extent to which it measures what it purports to measure. It must have face validity which means that it must appear sensible and appropriate; concurrent or criterion validity showing how it agrees with other scales; content validity which is an indication of the relevance of items and their relative importance, and construct or predictive validity which indicated whether the scale can distinguish appropriate groups. Thus, a good measure of menopausal symptoms would appear appropriate to menopausal women, would correlate positively with other scales, include relevant items such as libido, and would distinguish between pre menopausal and peri menopausal women scores on other measures of menopausal symptoms.

6. Measures of quality of life There is no one right or correct way to measure quality of life and the measurement needs to be tailored to the aim of the assessment. Quality of life can be measured by asking the person themselves, their carer or their health professionals. The meaning of the measure will depend on who is the rater, but also the purpose of the measure. In studies of dementia it may be very important to ask the carer and in hospital, assessments may be made by nursing staff. Assessments can be made by standardised questions, individualised questions and by standard scales. Standardised scales are most often used in research studies or in audit. The Nottingham Health Profile [9] is a simple scale and can be used in community studies. It gives a very functional assessment. However, it is now more usual to have specific scales of specific conditions or social contexts. In menopause research, the Greene Climacteric scale [10] and the Women’s Health Questionnaire [11] have been developed in the UK from clinic populations based on factor analysis and have good psychometric properties. In Germany, the Menopause Rating Scale (MRS) [12] provides three subscales and makes good many deficiencies of the Kupperman index. It has good psychometric properties with high levels of reliability [13]. These scales are all symptom-based, but quality of life research has taken a much broader view and is less illness based. There has been considerable research in the USA in the development of the SDF36 scales with subsequent validation in the UK [14,15]. The SF 36 provides eight subscales covering physical and social functioning, role limitations, pain, energy/vitality and general and mental health. It takes about 10 min to complete and can be used in postal surveys. In a significant study [16], the SF36 was compared with other standardised scales in a study of over 300 women. It

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was found that the SF36 and MRS correlated negatively for both somatic and psychological symptoms. The more symptoms the worse the quality of life, but the correlations were strongest for psychological symptoms. The closest associations were found in the most severe and the least severe menopausal symptoms. The highest correlations were in physical role functioning, bodily pain, vitality and emotional role functioning. However, all these items of the scales are interrelated and the scales were dominated by symptom reports, reflecting the illness model. There was no attempt to individualise the menopausal experience and of course they are culturally dependent, reflecting Western concepts of health. An individual approach has been taken in the Patient Generated Index of Quality of Life [17]. It asks people to generate their own list of five areas relating to quality of life and to allocate a value to reflecting their relative important to them. This allows individuals to generate their own priorities. It would allow mobility to be considered more important than pain. It is probably particularly useful in assessing change in areas of health that are more individually determined than societal. It may be less suitable for postal surveys but has intuitive appeal and may be very acceptable, so increasing response rates.

7. Conclusion If quality of life is closely related to menopausal symptoms, then a scale that measures symptomatology may be a good measure of quality of life, but if menopausal symptoms are only a small part of changes to women in mid life, then a more general measure would be more appropriate.

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[13] H.P.G. Schneider, L.A.J. Henineman, H.-P. Rosemeier, P. Potthoff, H.M. Behre, The Menopause Rating scale (MRS): reliability of scores of menopausal complaints, Climacteric 3 (2000) 59 – 64. [14] C. Jenkinson, Comparison of UK and US methods for weighting and scoring the SF36 summary measures, J. Public Health Med. 21 (1999) 3270 – 3376. [15] C. Jenkinson, S. Stewart Brown, S. Paterson, C. Plaice, Assessment of the SGF-36 version 2 in the United Kingdom, J. Epidemiol. Community Health 53 (1999) 46 – 50. [16] H.P.G. Schneider, L.A.J. Henineman, H.-P. Rosemeier, P. Potthoff, H.M. Behre, Menopause Rating scale (MRS): comparison with Kupperman index and quality-of-life scale SF-36, Climacteric 3 (2000) 50 – 58. [17] D.A. Ruta, A.M. Garratt, M. Leng, I.T. Russell, L.M. Macdonald, A new approach to the measurement of quality of life: the patient generated index (PGI), Med. Care 32 (1994) 1109 – 1126.