J.C.J.M. de Haes

The multidimensional Fatigue Inventory (MFI) psychometric qualities of an instrument to assess fatigue

The Multidimensional Fatigue Inventory (MFI) is a 20-item self-report instrument designed to measure fatigue. It covers the following dimensions: General Fatigue, Physical Fatigue, Mental Fatigue, Reduced Motivation and Reduced Activity. This new instrument was tested for its psychometric properties in cancer patients receiving radiotherapy, patients with the chronic fatigue syndrome, psychology students, medical students, army recruits and junior physicians. We determined the dimensional structure using confirmatory factor analyses (LISRELs unweighted least squares method). The hypothesized five-factor model appeared to fit the data in all samples tested (AGFIs > 0.93). The instrument was found to have good internal consistency, with an average Cronbachs alpha coefficient of 0.84. Construct validity was established after comparisons between and within groups, assuming differences in fatigue based on differences in circumstances and/or activity level. Convergent validity was investigated by correlating the MFI-scales with a Visual Analogue Scale measuring fatigue (0.22 < r < 0.78). Results, by and large, support the validity of the MFI.

Is a single-item visual analogue scale as valid, reliable and responsive as multi-item scales in measuring quality of life?

Purpose: To compare the validity, reliability and responsiveness of a single, global quality of life question to multi-item scales. Method: Data were obtained from 83 consecutive patients with oesophageal adenocarcinoma undergoing either transhiatal or transthoracic oesophagectomy. Quality of life was measured at baseline, 5 weeks, 3 and 12 months post-operatively with a single-item Visual Analogue Scale (VAS) ranging from 0 to 100, the multi-item Medical Outcomes Study Short Form-20 (MOS SF-20) and Rotterdam Symptom Check-List (RSCL). Convergent and discriminant validity, test–retest reliability and both distribution-based and anchor-based responsiveness were evaluated. Major findings: At baseline and at 5 weeks, the VAS showed high correlations with the MOS SF-20 health perceptions scale (r = 0.70 and 0.72) and moderate to high correlations with all other subscales of the MOS SF-20 and RSCL (r = 0.29–0.70). The test–retest reliability intra-class correlation for the VAS was 0.87. At 5 weeks post-operatively, the distribution-based responsiveness was moderate for the VAS (standardised response mean: −0.47; effect size: −0.56), high for the physical subscales of the MOS SF-20 and RSCL (−1.08 to −1.51) and low for the psychological subscales (0.11 to −0.25). Five weeks post-operatively, anchor-based responsiveness was highest for the VAS (r = 0.54). Conclusion: The VAS is an instrument with good validity, excellent reliability, moderate distribution-based responsiveness and good anchor-based responsiveness compared to multi-item questionnaires. Its use is recommended in clinical trials to assess global quality of life.

Application of the multidimensional fatigue inventory (MFI-20) in cancer patients receiving radiotherapy.

In this paper the psychometric properties of the multidimensional fatigue inventory (MFI-20) are established further in cancer patients. The MFI is a 20-item self-report instrument designed to measure fatigue. It covers the following dimensions: general fatigue, physical fatigue, reduced activity, reduced motivation and mental fatigue. The instrument was used in a Dutch and Scottish sample of cancer patients receiving radiotherapy. The dimensional structure was assessed using confirmatory factor analyses (Lisrels unweighted least-squares method). The hypothesised five-factor model appeared to fit the data in both samples (adjusted goodness of fit; AGFI: 0.97 and 0.98). Internal consistency of the separate scales was good in both the Dutch and Scottish samples with Cronbachs alpha coefficients ranging from 0.79 to 0.93. Construct validity was assessed by correlating the MFI-20 to activities of daily living, anxiety and depression. Significant relations were assumed. Convergent validity was investigated by correlating the MFI scales with a visual analogue scale measuring fatigue and with a fatigue-scale derived from the Rotterdam Symptom Checklist. Results support the validity of the MFI-20. The highly similar results in the Dutch and Scottish sample suggest that the portrayal of fatigue using the MFI-20 is quite robust.

Fatigue in cancer patients

In this paper an overview is presented on what is currently known of fatigue in cancer. Fatigue is considered to be a multi-dimensional concept, that should be measured as such. However, fatigue has been assessed mostly by single items in general symptom checklists. The few specific instruments that have been used in cancer patient populations are discussed. The majority of cancer patients, about 70%, report feelings of fatigue during radio- or chemotherapy. Follow-up results show that, at least for some diagnoses, patients remain fatigued long after treatment has ended. Somatic and psychological mechanisms that have been proposed to explain fatigue are discussed. It is argued that the significance of the results obtained on fatigue as a symptom in cancer depends on comparison with other patient and non-patient populations. Also the occurrence of a response-shift has to be considered, leading to under reporting of fatigue. Finally, possible interventions to decrease feelings of fatigue are presented.

Quality of life in patients with Parkinson's disease: development of a questionnaire.

OBJECTIVES--To develop and test a questionnaire for measuring quality of life in patients with Parkinsons disease. METHODS--An item pool was developed based on the experience of patients with Parkinsons disease and of neurologists; medical literature on the problems of patients with Parkinsons disease; and other quality of life questionnaires. To reduce the item pool, 13 patients identified items that were a problem to them and rated their importance. Items which were most often chosen and rated most important were included in the Parkinsons disease quality of life questionnaire (PDQL). The PDQL consists of 37 items. To evaluate the discriminant validity of the PDQL three groups of severity of disease were compared. To test for convergent validity, the scores of the PDQL were tested for correlation with standard indices of quality of life. RESULTS--The PDQL was filled out by 384 patients with Parkinsons disease. It consisted of four subscales: parkinsonian symptoms, systemic symptoms, emotional functioning, and social functioning. The internal-consistency reliability coefficients of the PDQL subscales were high (0.80-0.87). Patients with higher disease severity had significantly lower quality of life on all PDQL subscales (P < 0.05). Almost all PDQL subscales correlated highly (P < 0.001) with the corresponding scales of the standard quality of life indices. CONCLUSION--The PDQL is a relevant, reliable, and valid measure of the quality of life of patients with Parkinsons disease.

Goserelin versus cyclophosphamide, methotrexate, and fluorouracil as adjuvant therapy in premenopausal patients with node-positive breast cancer: The Zoladex Early Breast Cancer Research Association Study

PURPOSE Current adjuvant therapies have improved survival for premenopausal patients with breast cancer but may have short-term toxic effects and long-term effects associated with premature menopause. PATIENTS AND METHODS The Zoladex Early Breast Cancer Research Association study assessed the efficacy and tolerability of goserelin (3.6 mg every 28 days for 2 years; n = 817) versus cyclophosphamide, methotrexate, and fluorouracil (CMF) chemotherapy (six 28-day cycles; n = 823) for adjuvant treatment in premenopausal patients with node-positive breast cancer. RESULTS Analysis was performed when 684 events had been achieved, and the median follow-up was 6 years. A significant interaction between treatment and estrogen receptor (ER) status was found (P =.0016). In ER-positive patients (approximately 74%), goserelin was equivalent to CMF for disease-free survival (DFS) (hazard ratio [HR], 1.01; 95% confidence interval [CI], 0.84 to 1.20). In ER-negative patients, goserelin was inferior to CMF for DFS (HR, 1.76; 95% CI, 1.27 to 2.44). Amenorrhea occurred in more than 95% of goserelin patients by 6 months versus 58.6% of CMF patients. Menses returned in most goserelin patients after therapy stopped, whereas amenorrhea was generally permanent in CMF patients (22.6% v 76.9% amenorrheic at 3 years). Chemotherapy-related side effects such as nausea/vomiting, alopecia, and infection were higher with CMF than with goserelin during CMF treatment. Side effects related to estrogen suppression were initially higher with goserelin, but when goserelin treatment stopped, reduced to a level below that observed in the CMF group. CONCLUSION Goserelin offers an effective, well-tolerated alternative to CMF in premenopausal patients with ER-positive and node-positive early breast cancer.

The impact of breast-conserving treatment and mastectomy on the quality of life of early-stage breast cancer patients: a review.

In recent years, doubt has been shed on the necessity of mastectomy for women with early-stage breast cancer. Apart from purely medical studies comparing (radical) mastectomy to less intruding surgical treatment, a number of studies (N = 18) have been published investigating the impact of breast-conserving treatment versus mastectomy on quality of life. We review these studies with respect to medical issues (treatment modality, stage of disease), methodologic issues (design, measurement moment, sample size), and results (psychologic discomfort, changes in life patterns, fears and concerns). It is concluded that there is no solid proof of a better psychologic adjustment after breast-conserving treatment and that there are no substantial differences between the different treatment modalities in changes of life patterns and fears and concerns. However, the results with respect to body image and sexual functioning favor the use of breast-conserving treatment.

Cancer, fatigue and the return of patients to work—a prospective cohort study

Fatigue is a highly prevalent and debilitating symptom in cancer survivors. The aim of this study was to assess the impact of fatigue and other cancer-related symptoms on the return to work of cancer survivors. A prospective inception cohort study with 12 months of follow-up was initiated. At 6 months following the first day of sick leave, levels of fatigue, depression, sleep problems, physical complaints, cognitive dysfunction and psychological distress were assessed, in addition to clinical, sociodemographic and work-related factors. Data were obtained from one academic hospital and two general hospitals in the Netherlands. 235 patients who had a primary diagnosis of cancer and underwent treatment with curative intent were included. The rate of return to work was measured at 6, 12 and 18 months. Hazard ratios (HRs) for the duration of sick leave up to 18 months following the first day of sick leave were calculated. The rate of return to work increased from 24% at 6 months to 64% at 18 months following the first day of sick leave. Fatigue, diagnosis, treatment type, age, gender, depression, physical complaints and workload were all related to the time taken to return to work. Fatigue scores were also strongly related to diagnosis, physical complaints, and depression scores. Fatigue at 6 months predicted a longer sick leave with a hazard ratio of 0.71 (95% Confidence Interval (C.I.) 0.59-0.85), adjusted for diagnosis, treatment type, age and gender. In a multivariate Cox regression analysis, diagnosis, treatment, age, physical complaints and workload remained the only significant predictors of duration of the sick leave. 64% of cancer survivors returned to work within 18 months. Fatigue levels predicted the return to work. This was independent of the diagnosis and treatment, but not of other cancer-related symptoms. Better management of cancer-related symptoms is therefore needed to facilitate the return to work of cancer patients.

Fatigue and radiotherapy: (A) experience in patients undergoing treatment.

Cancer patients undergoing radiotherapy frequently report fatigue. However, knowledge of the importance of fatigue for these patients and of the factors associated with their fatigue is limited. The aim of the current investigation was to gain more insight into fatigue as related to radiotherapy by answering the following questions. First, how is the experience of fatigue best described? Secondly, to what extent is fatigue related to sociodemographic, medical (including treatment), physical and psychological factors? Finally, is it possible to predict which patients will suffer from fatigue after completion of radiotherapy? Patients with different types of cancer receiving radiotherapy with curative intent (n = 250) were interviewed before and within 2 weeks of completion of radiotherapy. During treatment, patients rated their fatigue at 2-weekly intervals. Results indicate a gradual increase in fatigue over the period of radiotherapy and a decrease after completion of treatment. Fatigue scores obtained after radiotherapy were only slightly, although significantly, higher than pretreatment scores. After treatment, 46% of the patients reported fatigue among the three symptoms that caused them most distress. Significant associations were found between post-treatment fatigue and diagnosis, physical distress, functional disability, quality of sleep, psychological distress and depression. No association was found between fatigue and treatment or personality characteristics. Multivariate regression analysis demonstrated that the intensity of pretreatment fatigue was the best predictor of fatigue after treatment. In view of this finding, a regression analysis was performed to gain more insight into the variables predicting pretreatment fatigue. The degree of functional disability and impaired quality of sleep were found to explain 38% of the variance in fatigue before starting radiotherapy. Fatigue in disease-free patients 9 months after treatment is described in paper (B) in this issue.

Utility assessment in cancer patients : adjustment of time tradeoff scores for the utility of life years and comparison with standard gamble scores

The standard gamble (SG) and the time tradeoff (TTO), two frequently used methods of utility assessment, have often been found to lead to different utilities for the same health state. The authors investigated whether adjustment of TTO scores for the utility of life years (risk attitude) eliminated this difference. In addition, the association between risk attitude and sociodemographic and medical variables was studied. In 30 disease-free testicular cancer patients, SG and TTO were used to assess the utilities of four health profiles relevant to testicular cancer. Utility of life years was estimated from certainty equivalents (CEs). SG scores were significantly higher than unadjusted TTO scores for all profiles. As the majority of patients (85%) were risk-averse, CE-adjusted TTO scores were higher than unadjusted scores, and were not significantly different from those obtained from the SG for three of the four profiles. However, adjusted scores were still slightly but consistently lower than SG scores. Possible explanations for this discrepancy are discussed. An association was found between risk aversion and medical treatment: patients who had received chemotherapy for their cancers were more risk-averse than were patients who had been in a surveillance protocol only. As risk aversion can have an impact on treatment decisions, it is important to assess the risk posture of the patient to whom the decision pertains. Key words: utility assessment; QALY; risk aversion; oncology; treatment preferences. (Med Decis Making 1994;14:82-90)