Using a discrete choice experiment to value the QLU-C10D: feasibility and sensitivity to presentation format.

PURPOSE: To assess the feasibility of using a discrete choice experiment (DCE) to value health states within the QLU-C10D, a utility instrument derived from the QLQ-C30, and to assess clarity, difficulty, and respondent preference between two presentation formats. METHODS: We ran a DCE valuation task in an online panel (N = 430). Respondents answered 16 choice pairs; in half of these, differences between dimensions were highlighted, and in the remainder, common dimensions were described in text and differing attributes were tabulated. To simplify the cognitive task, only four of the QLU-C10D's ten dimensions differed per choice set. We assessed difficulty and clarity of the valuation task with Likert-type scales, and respondents were asked which format they preferred. We analysed the DCE data by format with a conditional logit model and used Chi-squared tests to compare other responses by format. Semi-structured telephone interviews (N = 8) explored respondents' cognitive approaches to the valuation task. RESULTS: Four hundred and forty-nine individuals were recruited, 430 completed at least one choice set, and 422/449 (94 %) completed all 16 choice sets. Interviews revealed that respondents found ten domains difficult but manageable, many adopting simplifying heuristics. Results for clarity and difficulty were identical between formats, but the "highlight" format was preferred by 68 % of respondents. Conditional logit parameter estimates were monotonic within domains, suggesting respondents were able to complete the DCE sensibly, yielding valid results. CONCLUSION: A DCE valuation task in which only four of the QLU-C10D's ten dimensions differed in any choice set is feasible for deriving utility weights for the QLU-C10D.

QLU-C10D: a health state classification system for a multi-attribute utility measure based on the EORTC QLQ-C30.

PURPOSE: To derive a health state classification system (HSCS) from the cancer-specific quality of life questionnaire, the EORTC QLQ-C30, as the basis for a multi-attribute utility instrument. METHODS: The conceptual model for the HSCS was based on the established domain structure of the QLQ-C30. Several criteria were considered to select a subset of dimensions and items for the HSCS. Expert opinion and patient input informed a priori selection of key dimensions. Psychometric criteria were assessed via secondary analysis of a pooled dataset comprising HRQOL and clinical data from 2616 patients from eight countries and a range of primary cancer sites, disease stages, and treatments. We used confirmatory factor analysis (CFA) to assess the conceptual model's robustness and generalisability. We assessed item floor effects (>75 % observations at lowest score), disordered item response thresholds, coverage of the latent variable and differential item function using Rasch analysis. We calculated effect sizes for known group comparisons based on disease stage and responsiveness to change. Seventy-nine cancer patients assessed the relative importance of items within dimensions. RESULTS: CFA supported the conceptual model and its generalisability across primary cancer sites. After considering all criteria, 12 items were selected representing 10 dimensions: physical functioning (mobility), role functioning, social functioning, emotional functioning, pain, fatigue, sleep, appetite, nausea, bowel problems. CONCLUSIONS: The HSCS created from QLQ-C30 items is known as the EORTC Quality of Life Utility Measure-Core 10 dimensions (QLU-C10D). The next phase of the QLU-C10D's development involves valuation studies, currently planned or being conducted across the globe.

Testing the measurement invariance of the EORTC QLQ-C30 across primary cancer sites using multi-group confirmatory factor analysis.

PURPOSE: The EORTC Quality of Life Questionnaire is a widely used cancer-specific quality of life instrument comprising a core set of 30 items (QLQ-C30) supplemented by cancer site-specific modules. The purpose of this paper was to examine the extent to which the conventional multi-item domain structure of the QLQ-C30 holds across patients with seven different primary cancer sites. METHODS: Multi-group confirmatory factor analysis was used to test whether a measurement model of the QLQ-C30 was invariant across cancer sites. Configural (same patterns of factor loadings), metric (equivalence of factor loadings) and scalar (equivalence of thresholds) invariance amongst the cancer site groups were assessed (N = 1,906) by comparing the fit of a model with these parameters freely estimated to a model where estimates were constrained to be equal for the corresponding items in each group. RESULTS: All groups exhibited good model fit except for the prostate group, which was excluded. Only 1 of 576 parameters was found to differ between primary sites: specifically, the first threshold of Item 1 in the breast cancer group exhibited non-invariance. In a post hoc analysis, several instances of non-invariance by treatment status (baseline, on-treatment, off-treatment) were observed. CONCLUSIONS: Given only one instance of non-invariance between cancer sites, there is a reason to be confident in the validity of conclusions drawn when comparing QLQ-C30 domain scores between different sites and when interpreting the scores of heterogeneous samples, although future research should assess the potential impact of confounding variables such as treatment and gender.

Can individual patients assess differences in quality of life between groups of patients?

This qualitative study piloted a method for eliciting patient opinion on the size of group differences in quality of life (QOL) scores from the EORTC QLQ-C30. Using scenarios from published studies, patients were asked the differences in QOL they would expect between two groups of patients or a group of patients over time. Interviews were transcribed verbatim and thematic analysis used. Eleven breast cancer patients were interviewed. The final thematic framework consisted of three major themes: (1) their ability to use published data to judge the size of differences in QOL scores, (2) their ability to gain familiarity and understanding of the QLQ-C30 questionnaire in an interview situation and (3) their ability to understand and assess differences from a group of patients rather than on an individual basis. Patients felt able to understand the questionnaire and scoring. They provided an opinion on whether differences in QOL scores were trivial, small, medium or large. Patient perspectives were often based on their own experience of the disease and treatments and their opinions were varied. In order to estimate clinically meaningful differences from published literature, a larger number of patients with varied experiences would be required and a consensus process used to align opinions where possible.

Is there a genetic cause for cancer cachexia? - a clinical validation study in 1797 patients.

BACKGROUND: Cachexia has major impact on cancer patients' morbidity and mortality. Future development of cachexia treatment needs methods for early identification of patients at risk. The aim of the study was to validate nine single-nucleotide polymorphisms (SNPs) previously associated with cachexia, and to explore 182 other candidate SNPs with the potential to be involved in the pathophysiology. METHOD: A total of 1797 cancer patients, classified as either having severe cachexia, mild cachexia or no cachexia, were genotyped. RESULTS: After allowing for multiple testing, there was no statistically significant association between any of the SNPs analysed and the cachexia groups. However, consistent with prior reports, two SNPs from the acylpeptide hydrolase (APEH) gene showed suggestive statistical significance (P=0.02; OR, 0.78). CONCLUSION: This study failed to detect any significant association between any of the SNPs analysed and cachexia; although two SNPs from the APEH gene had a trend towards significance. The APEH gene encodes the enzyme APEH, postulated to be important in the endpoint of the ubiquitin system and thus the breakdown of proteins into free amino acids. In cachexia, there is an extensive breakdown of muscle proteins and an increase in the production of acute phase proteins in the liver.

Establishing the European Norm for the health-related quality of life domains of the computer-adaptive test EORTC CAT Core.

OBJECTIVE: The computer-adaptive test (CAT) of the European Organisation for Research and Treatment of Cancer (EORTC), the EORTC CAT Core, assesses the same 15 domains as the EORTC QLQ-C30 health-related quality of life questionnaire but with increased precision, efficiency, measurement range and flexibility. CAT parameters for estimating scores have been established based on clinical data from cancer patients. This study aimed at establishing the European Norm for each CAT domain based on general population data. METHODS: We collected representative general population data across 11 European Union (EU) countries, Russia, Turkey, Canada and the United States (n ≥ 1000/country; stratified by sex and age). We selected item subsets from each CAT domain for data collection (totalling 86 items). Differential item functioning (DIF) analyses were conducted to investigate cross-cultural measurement invariance. For each domain, means and standard deviations from the EU countries (weighted by country population, sex and age) were used to establish a T-metric with a European general population mean = 50 (standard deviation = 10). RESULTS: A total of 15,386 respondents completed the online survey (n = 11,343 from EU countries). EORTC CAT Core norm scores for all 15 countries were calculated. DIF had negligible impact on scoring. Domain-specific T-scores differed significantly across countries with small to medium effect sizes. CONCLUSION: This study establishes the official European Norm for the EORTC CAT Core. The European CAT Norm can be used globally and allows for meaningful interpretation of scores. Furthermore, CAT scores can be compared with sex- and age-adjusted norm scores at a national level within each of the 15 countries.

General population normative data for the EORTC QLQ-C30 health-related quality of life questionnaire based on 15,386 persons across 13 European countries, Canada and the Unites States.

OBJECTIVE: The European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 health-related quality of life questionnaire is one of the most widely used cancer-specific health-related quality of life questionnaires worldwide. General population norm data can facilitate the interpretation of QLQ-C30 data obtained from cancer patients. This study aimed at systematically collecting norm data from the general population to develop European QLQ-C30 norm scores and to generate comparable norm data for individual countries in Europe and North America. METHODS: We collected QLQ-C30 data from the general population across 11 European Union (EU) countries, Russia, Turkey, Canada and United States (n ≥ 1000/country). Representative samples were stratified by sex and age groups (18-39, 40-49, 50-59, 60-69 and ≥ 70 years). After applying weights based on the United Nations population distribution statistics, we calculated QLQ-C30 domain scores to generate a 'European QLQ-C30 Norm' based on the EU countries. Further, we calculated QLQ-C30 norm scores for all 15 individual countries. RESULTS: A total of 15,386 respondents completed the online survey. For the EU sample, most QLQ-C30 domains showed differences by sex/age, with men scoring somewhat better health than women, while age effects varied across domains. Substantially larger differences were seen in inter-country comparisons, with Austrian and Dutch respondents reporting consistently better health compared with British and Polish respondents. CONCLUSIONS: This study is the first to systematically collect EORTC QLQ-C30 general population norm data across Europe and North America applying a consistent data collection method across 15 countries. These new norm data facilitate valid intra-country as well as inter-country comparisons and QLQ-C30 score interpretation.

Fetal, infant, and childhood growth and adult blood pressure: a longitudinal study from birth to 22 years of age.

BACKGROUND: People who are small at birth tend to have higher blood pressure in later life. However, it is not clear whether it is fetal growth restriction or the accelerated postnatal growth that often follows it that leads to higher blood pressure. METHODS AND RESULTS: We studied blood pressure in 346 British men and women aged 22 years whose size had been measured at birth and for the first 10 years of life. Their childhood growth was characterized using a conditional method that, free from the effect of regression to the mean, estimated catch-up growth. People who had been small at birth but who gained weight rapidly during early childhood (1 to 5 years) had the highest adult blood pressures. Systolic pressure increased by 1.3 mm Hg (95% CI, 0.3 to 2.3) for every standard deviation score decrease in birth weight and, independently, increased by 1.6 mm Hg (95% CI, 0.6 to 2.7) for every standard deviation score increase in early childhood weight gain. Adjustment for adult body mass index attenuated the effect of early childhood weight gain but not of birth weight. Relationships were smaller for diastolic pressure. Weight gain in the first year of life did not influence adult blood pressure. CONCLUSIONS: Part of the risk of adult hypertension is set in fetal life. Accelerated weight gain in early childhood adds to this risk, which is partly mediated through the prediction of adult fatness. The primary prevention of hypertension may depend on strategies that promote fetal growth and reduce childhood obesity.

Health-related quality of life in the general Norwegian population assessed by the European Organization for Research and Treatment of Cancer Core Quality-of-Life Questionnaire: the QLQ=C30 (+ 3).

PURPOSE: To obtain reference data on health-related quality of life (HRQOL) for the functional and symptom scales and single items of the European Organization for Research and Treatment of Cancer Core Quality-of-Life Questionnaire (EORTC QLQ-C30 [+ 3]) in a representative sample of the Norwegian general population. PATIENTS AND METHODS: A randomly selected sample of 3,000 people from the Norwegian population, aged 18 to 93 years, who represent geographic diversity, took part in this postal survey. The EORTC QLQ-C30 (+ 3) and a questionnaire about demographic data and health were sent by mail. A new questionnaire package was sent as a reminder after 3 weeks. RESULTS: The survey yielded a high response rate with 1,965 of 2,892 eligible persons responding (68%). There was a low amount of missing data (1.8%). Internal consistency was highly satisfactory and yielded Cronbach's alpha coefficients greater than 0.70 for all but two functional scales and one symptom scale. The sensitivity of the questionnaire was shown by the excellent discrimination between age and sex groups. Clinical validity was shown by the distinct differences according to age and sociodemographic characteristics. Women reported lower functional status and global quality of life (mean scale scores from 71.7 to 91.0) than men (mean scale scores from 75.4 to 94.4), and also more symptoms and problems. This was remarkably consistent across age groups, as was a decline in functional status with an increase in age. CONCLUSION: This is the first study that presented reference data from the EORTC QLQ-C30 (+ 3) in a sample from a general population and seems to provide valid measures of HRQOL within different age groups. The results may serve as a guideline for clinicians when interpreting HRQOL in their own groups of patients, and contributes to a better understanding of the significance of mean scores and their clinical relevance.

Health-related quality of life 1 year after allogeneic or autologous stem-cell transplantation: a prospective study.

PURPOSE: To evaluate health-related quality of life (HRQOL) in adults treated with high-dose chemotherapy followed by allogeneic (SCT) and autologous (ASCT) stem-cell transplantation 1 year after transplantation, using data from concurrent lymphoma patients receiving combination chemotherapy (CT) as a reference. MATERIALS AND METHODS: Forty-one leukemia patients (SCT group), 51 lymphoma patients (ASCT group), and 85 CT patients completed the European Organization for Research and Treatment of Cancer QLQ-C30 questionnaire at baseline and after 1 year. RESULTS: The SCT group (median age, 36 years) had better functioning scores and less symptomatology at baseline compared with the ASCT (median age, 41 years) and CT (median age, 37 years) groups. Statistically significant differences of 10 or more points on the 0 to 100 scales were found for 10 of 15 scales and items (P< or =.01) between the SCT and ASCT groups. Global quality of life (79 v 58, P<.0001), role function (83 v 65, P = .001), sleep disturbances (6 v 28, P<.0001), and fatigue (25 v 44, P = .0001) deviated most. The differences were 10 or more points for seven of 15 scales and items comparing the SCT and CT groups, with sleep disturbances (6 v 35, P<.0001) and pain (11 v 29, P<.01) deviating most. Differences across groups were smaller after 1 year; cognitive function was the only scale with a statistically significant difference (ASCT 80 v CT 89; P = .002). Patterns of change in HRQOL scores were different between groups during follow-up. A great improvement was found in the ASCT group (P<.01 for emotional and role function, fatigue, appetite, and constipation), whereas no significant changes were observed for the SCT group. CONCLUSION: Prospective studies with extended follow-up periods are necessary to separate a slow recovery process from more permanently reduced HRQOL after transplantation and to examine the late side effects from previous treatment.

Quality of life in head and neck cancer patients: validation of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-H&N35.

PURPOSE: The aim of this study was to define the scales and test the validity, reliability, and sensitivity of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ)-H&N35, a questionnaire designed to assess the quality of life of head and neck (H&N) cancer patients in conjunction with the general cancer-specific EORTC QLQ-C30. PATIENTS AND METHODS: Questionnaires were given to 500 H&N cancer patients from Norway, Sweden, and the Netherlands as part of two prospective studies. The patients completed the questionnaires before, during (Norway and Sweden only), and after treatment, yielding a total of 2070 completed questionnaires. RESULTS: The compliance rate was high, and the questionnaires were well accepted by the patients. Seven scales were constructed (pain, swallowing, senses, speech, social eating, social contact, sexuality). Scales and single items were sensitive to differences between patient subgroups with relation to site, stage, or performance status. Most scales and single items were sensitive to changes, with differences of various magnitudes according to the site in question. The internal consistency, as assessed by Cronbach's alpha coefficient, varied according to assessment point and within subsamples of patients. A low overall alpha value was found for the speech and the senses scales, but values were higher in assessments of patients with laryngeal cancer and in patients with nose, sinus, and salivary gland tumors. Scales and single items in the QLQ-H&N35 seem to be more sensitive to differences between groups and changes over time than do the scales and single items in the core questionnaire. CONCLUSION: The QLQ-H&N35, in conjunction with the QLQ-C30, provides a valuable tool for the assessment of health-related quality of life in clinical studies of H&N cancer patients before, during, and after treatment with radiotherapy, surgery, or chemotherapy.

Using reference data on quality of life--the importance of adjusting for age and gender, exemplified by the EORTC QLQ-C30 (+3).

Interpretation of health related quality of life (HRQOL) results in cancer patients is facilitated by knowledge of the levels of HRQOL in the general population. However, direct comparisons can be misleading unless age and gender are considered. We demonstrate the derivation of age- and gender-specific 'expected' values from population reference values by means of simple calculations. This survey included 3000 randomly selected Norwegians above 18 years of age who received the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC QLQ-C30 (+3) by mail. 1965 responses from 2,892 eligible persons (68%) were received. The population was divided into six disease groups based on self-reported health problems. The observed mean scale scores of the different groups deviated greatly from those obtained in the general population. The score for physical function, for example, was 72 for cancer patients and ranged from 73.3 to 82.5 in other disease groups, as opposed to 89.9 in the general population and 98.9 in those with no health problems. The range for one of the quality of life (QOL) scales was 57.7 to 84.7 compared with 73.7 in the general population. Expected mean scores for the patient groups were computed from the reference values, based on the concept of equivalence of age and gender. The differences between the observed mean scores and the reference values were strongly mediated by this method. The expected scores for physical function then ranged from 83.3 to 93.1 and from 70.3 to 75 for the QOL scale. The impact of age and gender on the reference data from the EORTC QLQ-C30 (+3) obtained in a general population shows that these variables must be considered when interpreting data on HRQOL for cancer patients. The demonstration of how to generate mean values which are adjusted according to the age and gender distribution of a population should increase the usefulness of this questionnaire among clinicians.

Randomised consent designs in cancer clinical trials.

In 1977, Zelen proposed a new design for clinical trials with the aim of increasing recruitment by avoiding some of the problems associated with obtaining informed consent. These 'randomised consent' designs have proved controversial, and have not often been used. This paper explains the statistical aspects of single and double randomised consent designs and reviews some of the ethical issues. All identified published cancer treatment trials using a randomised consent design are considered in some detail. Reasons for and against the use of these designs are summarised.

Quality of life assessment in clinical trials--guidelines and a checklist for protocol writers: the U.K. Medical Research Council experience. MRC Cancer Trials Office.

Many clinical trials groups now routinely consider including Quality of Life (QoL) assessment in trials. Indeed, several have policies stating that QoL should be considered as a potential endpoint in all new trials and that if it is not to be evaluated the applicants should justify not doing so. However, inclusion of QoL in clinical trials presents a number of difficult organisational issues, and serious problems in compliance have frequently been reported. Thus, in multicentre clinical trials many of the expected QoL questionnaires fail to be successfully completed and returned, although a few groups have claimed high success rates. However, it is well recognised that if questionnaires are missing, there may be bias in the interpretation of trial results, and the estimates of treatment differences and the overall level of QoL may be inaccurate and misleading. Hence it is important to seek methods of improving compliance, at the level of both the participating institution and the patient. We describe a number of methods for addressing these issues, which we suggest should be considered by all those writing clinical trial protocols involving QoL assessment. These are based upon over a decade of experience with assessing QoL in Medical Research Council (MRC) cancer clinical trials. In particular, we provide a checklist for points that should be covered in protocols. Examples are given from a range of current MRC Cancer Trials Office protocols, which it is proposed might act as templates when writing new protocols.

A 12 country field study of the EORTC QLQ-C30 (version 3.0) and the head and neck cancer specific module (EORTC QLQ-H&N35) in head and neck patients. EORTC Quality of Life Group.

This study tests the reliability and validity of the European Organization for Research and Treatment of Cancer (EORTC) head and neck cancer module (QLQ-H&N35) and version 3.0 of the EORTC Core Questionnaire (QLQ-C30) in 622 head and neck cancer patients from 12 countries. The patients completed the QLQ-C30, the QLQ-H&N35 and a debriefing questionnaire before antineoplastic treatment or at a follow-up. 232 patients receiving treatment completed a second questionnaire after treatment. Compliance was high and the questionnaire was well accepted by the patients. Multitrait scaling analysis confirmed the proposed scale structure of the QLQ-H&N35. The QLQ-H&N35 was responsive to differences between disease status, site and patients with different Karnofsky performance status, and to changes over time. The new physical functioning scale (with a four-point response format) of version 3.0 of the QLQ-C30 was shown to be more reliable than previous versions. Thus, the QLQ-H&N35, in conjunction with the QLQ-C30, appears to be reliable, valid and applicable to broad multicultural samples of head and neck cancer patients.

Blood pressure in four and five-year-old children: the effects of environment and other factors in it's measurement--the Brompton study.

Systolic blood pressure was measured on a total of 1855 occasions in 1307 children aged four and five years, and compared with values obtained since birth in the same children. There was a rapid rise in blood pressure in the first month of life. The mean blood pressure then only rose from 93 mmHg at six months to 98 mmHg at five years. The 95th percentile was 113 to 114 mmHg over this period. In children aged four and five years, over the ranges studied, blood pressure was not importantly affected by place of measurement, time of day, time since previous meal, or ambient temperature. However, blood pressure was approximately 1.6 mmHg higher in winter than in summer (P less than 0.01). Nevertheless, it is unlikely that these factors are of significance when making clinical measurements. Blood pressure was correlated with weight at all ages. Between the ages of four and five years, the index, weight/height 1.70 was the best function of adiposity tested that was independent of age between four and five years. It is suggested that this or the Quetelet Index (weight/height2) are suitable indices for adjusting blood pressure for body build in children aged four and five years.

Anxiety and depression in breast cancer patients at low risk of recurrence compared with the general population: a valid comparison?

Breast cancer and its treatment have been associated with psychological morbidity. In this study our aim was to quantify the excess anxiety and depression resulting from breast cancer. We compared 538 newly diagnosed breast cancer patients at low risk of recurrence (87.0% responded) to 872 women randomly selected from the Danish general population (69.7% responded) using the Hospital Anxiety and Depression Scale (HADS). Contrary to expectations, the proportions classified as "cases" of anxiety and depression were not significantly different in the two groups. The breast cancer patients' mean HADS scores were significantly lower than those in the general population sample (anxiety, P = 0.021; depression, P < 0.001), indicating less anxiety and depression. However, we question the validity of this comparison. The HADS may not be suitable for use in the general population and there may be methodological problems in comparisons of groups whose life situations are very different.