Assessing the validity of the SF-36 General Health Survey

Our objective was to assess the validity of the SF-36 General Health Survey against the Social Maladjustment Schedule (SMS) and two questionnaire measures, the Social Problem Questionnaire and the Nottingham Health Profile (NHP) in a random subsample of 206 men and women from the Whitehall II study, a longitudinal survey of health and disease amongst 10,308 London-based civil servants. We found that social functioning on the SF-36 correlated significantly with social contacts, total satisfaction and total management scores on the SMS, and social isolation and emotional reactions on the NHP. General mental health on the SF-36 was associated with marriage, social contacts, leisure scores, total satisfaction and total management scores on the SMS, and emotional reactions, energy level and social isolation on the NHP. Conversely, physical functioning and physical role limitations were generally not associated with the SMS but were associated with physical abilities and pain on the NHP. In conclusion, this study offers evidence of the discriminant validity of the general mental health and physical functioning scales of the SF-36. We also found moderate construct and criterion validity for the social functioning scale of the SF-36 and considerable overlap between the general mental health and social functioning scales.     

Health-related quality of life in patients with thyroid disorders

Limited reports are available on quality of life (HRQL) in thyroid diseases, and no data are available in euthyroid disorders, such as goiter and Hashimoto thyroiditis. Also, asymptomatic patients may suffer a reduction in perceived health status due to distress related to physical appearance and awareness of disease. We measured HRQL by means of Medical Outcome Study Short Form-36 (SF-36) and Nottingham Health Profile (NHP) questionnaires in 368 patients (hypothyroid, 81; hyperthyroid, 45 (for both states including overt and subclinical states); Hashimoto thyroiditis, 51; euthyroid goiter, 191). The final scores of the domains were compared with age- and sex-adjusted Italian normative values, by computing the effect size. All domains of SF-36, except bodily pain, were reduced in thyroid disease; this was mainly the case of role limitation (both physical and emotional), general health and social functioning. The domains of NHP were less severely affected. HRQL was impaired also in the absence of altered hormone levels. Mood/behavior disturbances were present in a large proportion of patients and were significantly associated with poor HRQL. HRQL was significantly reduced in patients with thyroid diseases referred to a secondary level endocrinology unit. Perceived health status may be considered as an additional outcome of management and therapy of thyroid disorders.     

A comparison of the Nottingham Health Profile and Short Form 36 Health Survey in patients with chronic lower limb ischaemia in a longitudinal perspective

Background

Different generic quality of life instruments such as the Nottingham Health Profile (NHP) and the Short Form 36 Health Survey (SF-36) have revealed conflicting results in patients with chronic lower limb ischaemia in psychometric attributes in short-term evaluations. The aim of this study was to compare the NHP and the SF-36 regarding internal consistency reliability, validity, responsiveness and suitability as outcome measures in patients with lower limb ischaemia in a longitudinal perspective.

Methods

48 patients with intermittent claudication and 42 with critical ischaemia were included. Assessment was made before and one year after revascularization using comparable domains of the NHP and the SF-36 questionnaires.

Results

The SF-36 was less skewed and more homogeneous than the NHP. There was an average convergent validity in three of the five comparable domains one year postoperatively. The SF-36 showed a higher internal consistency except for social functioning one-year postoperatively and was more responsive in detecting changes over time in patients with intermittent claudication. The NHP was more sensitive in discriminating among levels of ischaemia regarding pain and more able to detect changes in the critical ischaemia group.

Conclusion

Both SF-36 and NHP have acceptable degrees of reliability for group-level comparisons, convergent and construct validity one year postoperatively. Nevertheless, the SF-36 has superior psychometric properties and was more suitable in patients with intermittent claudication. The NHP however, discriminated better among severity of ischaemia and was more responsive in patients with critical ischaemia.

     

The MOS SF-36 health survey questionnaire in severe chronic airflow limitation: Comparison with the Nottingham health profile

This study documents the cross-sectional, health-related quality of life (HRQOL) measures obtained at baseline for patients with severe chronic airways limitation (CAL) being assessed for home oxygen therapy (HOT) at the Flinders Medical Centre, Adelaide, South Australia. Two generic quality of life instruments, the Nottingham Health Profile (NHP) and the Medical Outcomes Study (MOS) short form 36-item questionnaire (SF-36), were administered by interview to the same patients to permit comparisons to be made between the two instruments. SF-36 mean scores were also compared with scores obtained in separate studies of a South Australian elderly general population and of groups of Australian subjects with various medical and psychiatric conditions. NHP mean scores were compared with scores from an elderly group of Adelaide residents from a household survey. HRQOL measures were obtained for 60 patients, 32 males and 28 females. At assessment for HOT, patients with severe CAL were experiencing severe impairment in their quality of life in comparison to age-matched South Australian norms, with physical disability the major limitation. There were several significant correlations between the domains of the SF-36 and the NHP which were predominantly gender-specific. Only small decrements in mental health were found with the SF-36 questionnaire. The SF-36 and the NHP appear to provide discrepant information for severely disabled CAL patients for the subjective domains of emotional and mental health.     

The feasibility and responsiveness of the health utilities index in patients with early-stage breast cancer: A prospective longitudinal study

Background The health utilities index (HUI3) is a health measurement instrument based on individuals’ preferences for different health states. Breast cancer (BC) is common, with a high proportion of long-term survivors, making evaluation of treatment effects important. Feasibility and responsiveness of HUI3 was compared to the short-form 36 (SF-36) in patients with BC. Methods HUI3 and SF-36 were administered eight times: at initial surgical consultation, 1 week before surgery; 1 week, 3, 6, 12, 18, and 24 months after surgery. Effect size, analysis of variance, and Pearson product moment correlations were calculated. BC data were compared to normative values. Results Eighty-five patients were enrolled. Ninety-one percent of planned assessments were completed. HUI3 showed significant responsiveness (P < 0.01) after surgery and during recovery. HUI3 scores correlated with SF-36 scores. Comparison to normative data demonstrated the significant detrimental effect of BC diagnosis. Results showed long-term effects of treatment on physical health and positive effects on mental/emotional health in BC survivors. Conclusion(s) HUI3 was found to be feasible and responsive in our cohort of BC patients. Changes in HUI3 values over time, and compared to normative data, paralleled SF-36 scores. HUI3 is a valuable tool in health-related quality of life and cost-utility studies in patients with BC.     

A comparison of three measures of perceived distress: results from a study of angina patients in general practice in Northern Ireland.

OBJECTIVE: To establish the effect of health education on the level of distress felt by patients with angina and to compare the results obtained using different measures. DESIGN: Randomised controlled trial of personal health education given every four months. SETTING: Eighteen general practices in the greater Belfast area. SUBJECTS: These comprised 688 patients aged less than 75 years and known to have had angina for at least six months: 342 were randomised to receive education and 346 no education. MAIN OUTCOME MEASURES: These were the Nottingham health profile (NHP), functional limitation profile (FLP), and a simple categorical scale (SCS). RESULTS: The intervention group showed a statistically significant improvement in health relative to the control group in terms of physical mobility and social isolation using the NHP. In terms of overall wellbeing, both the NHP and SCS results showed the intervention group had experienced statistically significant improvements in health relative to the control group. Results obtained using the NHP, FLP, and SCS were found to be correlated regardless of whether weighted or unweighted scores were used. CONCLUSION: The intervention produced a significant improvement in health status. Results from different survey instruments were correlated using both weighted and unweighted scores. An SCS was capable of detecting the improvement in health status.     

Use of the Nottingham Health Profile with patients after a stroke.

The Nottingham Health Profile (NHP) is easy to use with stroke patients and may be used with those who cannot manage more complicated mood questionnaires, such as the General Health Questionnaire (GHQ). Stroke patients rate their health, and especially emotions and feelings of social isolation, as much worse than that of people of similar age. NHP emotion scores correlate with objective measures of disability, length of hospital stay, and GHQ scores. The NHP is a valid indicator of depressed mood, and combining its components into a total score gives the greatest accuracy in detecting depression. Patients with high scores at one month continued to report large numbers of problems at six months after their stroke. Many patients experienced pain, disturbed sleep, and social isolation, which are important, potentially treatable problems not usually considered in the management of stroke patients. Many patients with problems did not see their general practitioner or any other source of help, and additional follow up was needed.     

Health related quality of life in patients with venous ulceration: Use of the Nottingham health profile

Introduction: The Nottingham health profile (NHP) has been used in several studies of patients being treated for chronic venous leg ulceration, though there is a paucity of information on the validity of the NHP in this patient group. This study was carried out to determine this validity and to compare and contrast the results with a previous study that had used the MOS short form 36 (SF-36) in this patient group. Methods: Patients in four health trusts suffering from venous ulceration were interviewed at entry and after 12 weeks of treatment using high compression bandaging. Information was collected on ulcer history, general medical history, and the NHP was completed at both time points. After 12 weeks, a record was made of whether all areas of ulceration had cleared from the patients' legs (healed) or whether some ulceration remained (unhealed). Results: Of the 383 patients who made up the study population, 37% experienced complete healing of their ulceration after 12 weeks of treatment. While internal consistencies of the NHP scores were reasonable (Cronbach's α > 0.63), there were a high proportion of patients who scored 0 (best possible health) at entry into the study, most notably for social isolation (67.5%), emotional status (48.9%) and energy (47.4%). Despite these limitations, there was strong evidence that treatment led to significant improvements in all dimensions of the NHP for the total group (all p < 0.01). These improvements were greatest in patients whose ulcers healed compared with patients whose ulcers failed to heal for bodily pain (mean difference d = 9.4, p = 0.004). Patients whose overall health status improved had significantly greater improvements for all dimensions of the NHP (p < 0.05). Conclusion: The NHP, has limitations in terms of a large floor effect (best possible health), but has similar internal consistency to the SF-36 in patients with leg ulceration. However, unlike the SF-36, the NHP is sensitive to change in the patients' ulcer status, and should therefore be considered in studies of venous leg ulcer healing. This revised version was published online in June 2006 with corrections to the Cover Date.     

Evidence for the sensitivity of the SF-36 health status measure to inequalities in health: results from the Oxford healthy lifestyles survey.

OBJECTIVES: The short form 36 (SF-36) health questionnaire may not be appropriate for population surveys assessing health gain because of the low responsiveness (sensitivity to change) of domains on the measure. An hypothesised health gain of respondents in social class V to that of those in social class I indicated only marginal improvement in self reported health. Subgroup analysis, however, showed that the SF-36 would indicate dramatic changes if the health of social class V could be improved to that of social class I. DESIGN: Postal survey using a questionnaire booklet containing the SF-36 and a number of other items concerned with lifestyles and illness. A letter outlining the purpose of the study was included. SETTING: The sample was drawn from family health services authority (FHSA) computerised registers for Berkshire, Buckinghamshire, Northamptonshire, and Oxfordshire. SAMPLE: The questionnaire was sent to 13,042 randomly selected subjects between the ages of 17-65. Altogether 9332 (72%) responded. OUTCOME MEASURES: Scores for the eight dimensions of the SF-36. STATISTICS: The sensitivity of the SF-36 was tested by hypothesising that the scores of those in the bottom quartile of the SF-36 scores in class V could be improved to the level of the scores from the bottom quartile of SF-36 scores in class I using the effect size statistic. RESULTS: SF-36 scores for the population at the 25th, 50th, and 75th centiles were provided. Those who reported worse health on each dimension of the SF-36 (ie in the lowest 25% of scores) differ dramatically between social class I and V. Large effect sizes were gained on all but one dimension of the SF-36 when the health of those in the bottom quartile of the SF-36 scores in class V were hypothesised to have improved to the level of the scores from the bottom quartile of SF-36 scores in class I. CONCLUSIONS: Analysis of SF-36 data at a population level is inappropriate; subgroup analysis is more appropriate. The data suggest that if it were possible to improve the functioning and wellbeing of those in worst health in class V to those reporting the worst health in class I the improvement would be dramatic. Furthermore, differences between the classes detected by the SF-36 are substantial and more dramatic than might previously have been imagined.     

Hypertension and health-related quality of life. an epidemiological study in Sweden

The aim of this study was to describe the relationship between hypertension and health-related quality of life (HRQL) in a Swedish general population using the 36-item short form questionnaire (SF-36). The study is based on a postal questionnaire that was sent to a random sample of 8000 inhabitants aged 20-84 years (response rate 68%) in Uppsala County, Sweden, in 1995. The results showed that those with hypertension scored lower in the linear regression analyses in most of the eight domains of the SF-36 than those without hypertension after controlling for age, sex, sociodemographic factors, and comorbidity. Diabetes and angina pectoris were related to lower scores in most of the domains of the SF-36. Previous myocardial infarction was associated with lower general health and vitality. Those with a previous stroke had lower scores in physical functioning, general health, vitality, and social functioning. The findings suggest that hypertensives represent a vulnerable population that merits special attention from health care providers and systems. This is especially important given that low HRQL can be a risk factor for subsequent cardiovascular events or complications.     

A comparison of the responsiveness of different generic health status measures in patients with asthma

Generic health status has been recommended to be measured separately from disease-specific health status, because they can yield complementary information. In particular, generic health status can provide comprehensive health ratings across various disorders. However, the weakness with generic measures is that they may be less responsive to clinical changes than disease-specific ones. Therefore, when using generic health status as an endpoint in clinical trials, the instrument to be used is a problem with respect to responsiveness. In the present study, we investigated and compared the responsiveness of health status measures during asthma treatment using three different generic instruments: the Medical Outcomes Study Short Form 36-items Health Survey (SF-36), the Nottingham Health Profile (NHP) and the EQ5D (EuroQoL), as well as one disease-specific instrument, the Asthma Quality of Life Questionnaire (AQLQ). Fifty-four new patients with asthma who consulted our clinic were recruited. The health status measurements were performed on the initial visit, and at 3 and 6 months. All subscales of the SF-36 showed a significant improvement during the first 6 months. Each dimension of the EQ5D showed stronger ceiling effects than the SF-36. With respect to the responsiveness indices, the SF-36 was regarded as more responsive than the NHP or EQ5D utility. The changes in the SF-36 had a weak to moderate correlation with the changes in the AQLQ. In conclusion, the SF-36 had a higher responsiveness for asthma as a generic measure than the NHP or EQ5D, and evaluated different aspects from the AQLQ. The SF-36 can be used effectively in asthma clinical trials.     

The relationship between physician cost and functional status in the elderly.

OBJECTIVE: To explore the relationship between functional status and physician cost (general practitioner/specialist) in an elderly population. DESIGN, SETTING AND PARTICIPANTS: A longitudinal study involving 328 patients aged 65 years or over admitted to medical and surgical wards of a Sydney metropolitan hospital over a 10-month period. MAIN OUTCOME MEASURES: Two predictive cost models were developed using multiple linear regression analyses. Nine predictors were modelled including functional status (Short Form 36; SF-36) and major diagnostic categories. These models were then applied to the Australian SF-36 norms to produce a profile of cost by level of functioning. RESULTS: After adjusting for potential confounders, five variables were found to be predictive of general practitioner cost at a 5% significance level. Females and age were positively associated, whereas case note mention of post-discharge services and high SF-36 vitality and role emotional scores were negatively predictive. For specialist cost, five variables were statistically significant. The SF-36 domains of physical functioning and mental health were positively associated. Higher vitality, role emotional scores and case note mention of post-discharge services were negatively associated. CONCLUSIONS: Cost models can be used to highlight the differences between general practitioner and specialist attendances, guide future physician care of the aged, and facilitate informed decision making.     

冠心病患者中文版SF-36和QOL-35量表的相关分析

目的 了解两种量表(SF-36和QOL-35)对生活质量分析的一致性.方法 2008年6月至2009年4月北京协和医院心内科就诊并进行冠状动脉造影的冠心病患者或可疑冠心病患者781例,采用中文版SF-36和QOL-35量表对患者的生活质量进行测量,并收集患者的一般人口学资料和临床资料.对SF-36和QOL-35量表结果进行简单相关分析和典型相关分析.结果 781例患者SF-36总得分为62.63±12.47,QOL-35总得分为62.70±9.69.简单相关分析显示SF-36总分和QOL-35总分(r=0.725,P＜0.01),SF-36生理机能和QOL-35独立生活能力(r=0.933,P＜0.01),SF-36精神健康和QOL-35心理健康(r=0.132,P＜0.01),SF-36社会功能和QOL-35社会功能(r=0.215,P＜0.01)之间均具有相关性.典型相关分析显示SF-36和QOL-35之间相关性显著(r=0.946,P＜0.01).结论 SF-36和QOL-35在评价冠心病患者生活质量总体水平一致.     

Whose Quality of Life? Ethical Implications in Patient-Reported Health Outcome Measurement

Objectives:  Patient-reported health status questionnaires intend to assess illness and therapy from the patients' perspective. To provide fair and valid assessments, they should be equally relevant to major subsets of respondents. Furthermore, disease-specific measures are assumed to be perceived as more relevant than generic ones. This study assessed these assumptions among people with Parkinson's disease.
Methods:  Cross-sectional data from 202 people with Parkinson's disease (54% men; mean age, 70) were analyzed regarding patient-rated relevance and predictors of patient-rated poor relevance of two generic [the 36-item Short Form Health Survey (SF-36) and Nottingham Health Profile (NHP)] and one disease-specific [Parkinson's Disease Questionnaire (PDQ-39)] health status questionnaire.
Results:  There were no differences in relevance ratings across the questionnaires. Poorer overall quality of life [odds ratio (OR), 2.459] and mental health (OR, 1.023) were associated with poorer patient-rated relevance of the SF-36, and higher age was associated with poorer patient-rated relevance of the PDQ-39 (OR, 1.040). No significant predictors were found for the NHP.
Conclusions:  The PDQ-39 failed to meet the assumption that disease-specific scales are more relevant than generic ones. Nevertheless, the most important implication of this study is an ethical one. Because the relevance of the SF-36 and PDQ-39 is perceived as poorer by those who fare least well and by older people, these scales may not reflect the perspectives of these groups. This challenges bioethical principles and threatens scientific validity. Perceived relevance of patient-centered outcomes needs to be considered, or the voice of vulnerable groups may be silenced, fair inferences prohibited, and opportunities for improved care lost.     

Performance of the Swedish SF-36 version 2.0

OBJECTIVES: To evaluate the performance of the first non-English (Swedish) SF-36 version 2.0 (V2) regarding scaling assumptions, reliability and validity, with special emphasis on the effects of extending the response scales of the two role functioning scales, role physical (RP) and role emotional (RE), from a dichotomous to a five-step format. METHODS: Questionnaires were mailed to a non-stratified, random national sample of 3000 18-75 year old Swedish residents in 1998-1999. Methods traditionally used in evaluating the original US SF-36 version 1.0 (V1) and other international versions were applied. RESULTS: A total of 73% of the questionnaires were returned. Scaling assumptions were satisfactorily met and generally enhanced compared with V1, particularly regarding the role functioning scales. Floor/ceiling effects were reduced and reliability estimates increased for the role scales. The factor structure was replicated and the relative validity of the role scales as measures of their components increased. Overall, the tests of the criterion-based validity using known groups comparisons produced results supporting hypotheses: scales from the physical domain distinguished best between groups expected to differ in physical health; and scales comprising the mental domain distinguished best between groups expected to differ in mental health. Furthermore, hypothesized differences in mean scale scores as a function of age and social risk factors were confirmed. CONCLUSIONS: The changes to the response formats of the role functioning scales have improved their precision, reliability and validity without jeopardizing the underlying structure of the original SF-36. These changes will likely further enhance the responsiveness of the SF-36.     

Longer response scales improved the acceptability and performance of the Nottingham Health Profile

OBJECTIVE: To test alternative response formats for the Nottingham Health Profile (NHP), in terms of acceptability, score distributions, and measurement properties. STUDY DESIGN AND SETTINGS: Randomized trial of four response formats for the NHP: original "yes/no" format, a 3-point similarity format ("applies completely/in part/not at all"), a 5-point intensity format ("completely true" to "completely false"), and a 5-point frequency format ("all the time" to "never"). Respondents were patients discharged from a hospital. We compared scores distributions, reliability coefficients, correlations with dimension-specific numerical scales, and patient ratings of the instrument. RESULTS: Response rates were similar for the four versions. The original response format had the fewest fully completed questionnaires, and the largest ceiling effects. Internal consistency and test-retest coefficients were acceptable for all versions, but were higher for the two 5-point formats. Correlations reflecting convergent and discriminant validity were higher for the longer response formats than for the original version. The frequency format received the highest ratings from patients, particularly from the sicker and older subgroups. CONCLUSIONS: The psychometric performance and patient acceptability of the NHP can be improved by using a 5-point frequency response format instead of the original dichotomous response format.     

Correlations between disease-specific and generic health status questionnaires in patients with advanced COPD: a one-year observational study

ABSTRACT: BACKGROUND: Longitudinal studies analyzing the correlations between disease-specific and generic questionnaires at different time points in patients with advanced COPD are lacking. The aim of this study was to determine whether and to what extent a disease-specific health status questionnaire (Saint George's Respiratory Questionnaire, SGRQ) correlates with generic health status questionnaires (EuroQol-5-Dimensions, EQ-5D; Assessment of Quality of Life instrument, AQoL; Medical Outcomes Study 36-Item Short-Form Health Survey, SF-36) at four different time points in patients with advanced COPD; and to determine the correlation between the changes in these questionnaires during one-year follow-up. METHODS: Demographic and clinical characteristics were assessed in 105 outpatients with advanced COPD at baseline. Disease-specific health status (SGRQ) and generic health status (EQ-5D, AQoL, SF-36) were assessed at baseline, four, eight, and 12 months. Correlations were determined between SGRQ and EQ-5D, AQoL, and SF-36 scores and changes in these scores. Agreement in direction of change was assessed. RESULTS: Eighty-four patients (80%) completed one-year follow-up and were included for analysis. SGRQ total score and EQ-5D index score, AQoL total score and SF-36 Physical Component Summary measure (SF-36 PCS) score were moderately to strongly correlated. The correlation of the changes between the SGRQ total score and EQ-5D index score, AQoL total score, SF-36 PCS, and SF-36 Mental Component Summary measure (SF-36 MCS) score were weak or absent. The direction of changes in SGRQ total scores agreed slightly with the direction of changes in EQ-5D index score, AQoL total score, and SF-36 PCS score. CONCLUSIONS: At four, eight and 12 months after baseline, SGRQ total scores and EQ-5D index scores, AQoL total scores and SF-36 PCS scores were moderately to strongly correlated, while SGRQ total scores were weakly correlated with SF-36 MCS scores. The correlations between changes over time were weak or even absent. Disease-specific health status questionnaires and generic health status questionnaires should be used together to gain complete insight in health status and changes in health status over time in patients with advanced COPD.     

Does being bilingual in English and Chinese influence changes in quality of life scale scores? Evidence from a prospective,population based study

Background: Bilinguals differ from monolinguals in language use, but the influence of bilingualism on changes in Health-Related Quality of Life (HRQoL) scores is not known. Objective: To determine the influence of bilingualism on changes in HRQoL scores. Research design: A prospective cohort study of a population-based, disproportionately stratified random sample of monolingual or bilingual ethnic Chinese who completed the Short-Form 36 Health Survey (SF-36) in English or Chinese twice in 2 years. Least squares regression models were used to assess the influence of bilingualism on SF-36 scores, while adjusting for the influence of questionnaire language and determinants of HRQoL. Results: Usable English and Chinese questionnaires were returned by 1013 and 910 subjects respectively (aged 21–65 years, 48.5% female, 52.8% bilingual). Bilinguals differed from monolinguals in known determinants of HRQoL (being younger and better educated), changes in determinants of HRQoL over 2 years (more bilinguals had changes in work or marital status) and had mean SF-36 scores that were up to 10 points higher than monolinguals. After adjusting for these differences, bilingualism did not influence 2 year change scores for any of 8 SF-36 scales. Conclusion: Bilingualism did not influence changes in HRQoL scores over 2 years in this large, population-based study of subjects fluent in English and/or Chinese (representing an alphabet and/or pictogram based language respectively).     

Quality of life in coronary patients

This study compared measures of quality of life (QOL) in two groups of coronary heart disease patients: one with myocardial infarction (MI) and one with angina (A). The population studied consisted of 49 patients from Group MI and 27 patients from Group A. A questionnaire was used to identify socio-demographic and clinical data, as well as data from the SF-36 instrument, to assess the patients' QOL. It was observed in both groups that the QOI declined in the following aspects: physical functioning, pain, general health condition, vitality, social functioning, and mental health. Socio-demographic and clinical variables influenced the QOL score. Studies aiming at a larger number of individuals and a better understanding of the effects of the variables above upon the QOL of coronary patients are needed.