Comparing translations of the EORTC QLQ-C30 using differential item functioning analyses

Cancer-Specific Health Utilities: Evaluation of Core Measurement Properties of the EORTC QLU-C10D in Lung Cancer Patients-Data from Four Multicentre LUX-Lung Trials, Applying Six Country Tariffs

BACKGROUND

Cost-utility analysis generally requires valid preference-based measures (PBMs) to assess the utility of patient health. While generic PBMs are widely used, disease-specific PBMs may capture additional aspects of health relevant for certain patient populations. This study investigates the construct and concurrent criterion validity of the cancer-specific European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Utility-Core 10 dimensions (QLU-C10D) in non-small-cell lung cancer patients.

METHODS

We retrospectively analysed data from four multicentre LUX-Lung trials, all of which had administered the EORTC Quality of Life Questionnaire (QLQ-C30) and the EQ-5D-3L. We applied six country-specific value sets (Australia, Canada, Italy, the Netherlands, Poland, and the United Kingdom) to both instruments. Criterion validity was assessed via correlations between the instruments' utility scores. Correlations of divergent and convergent domains and Bland-Altman plots investigated construct validity. Floor and ceiling effects were assessed.

RESULTS

The comparison of the EORTC QLU-C10D and EQ-5D-3L produced homogenous results for five of the six country tariffs. High correlations of utilities (r > 0.7) were found for all country tariffs except for the Netherlands. Moderate to high correlations of converging domain pairs (r from 0.472 to 0.718) were found with few exceptions, such as the Social Functioning-Usual Activities domain pair (max. r = 0.376). For all but the Dutch tariff, the EORTC QLU-C10D produced consistently lower utility values compared to the EQ-5D-3L (x̄ difference from - 0.082 to 0.033). Floor and ceiling effects were consistently lower for the EORTC QLU-C10D (max. 4.67% for utilities).

CONCLUSIONS

The six country tariffs showed good psychometric properties for the EORTC QLU-C10D in lung cancer patients. Criterion and construct validity was established. The QLU-C10D showed superior measurement precision towards the upper and lower end of the scale compared to the EQ-5D-3L, which is important when cost-utility analysis seeks to measure health change across the severity spectrum.

Cross-National Vaccine Concerns and Predictors of Vaccine Hesitancy in Not-Fully Vaccinated Individuals: Findings from USA, Canada, Sweden, and Italy

Vaccine hesitancy is a key contributor to reduced COVID-19 vaccine uptake and remains a threat to COVID-19 mitigation strategies as many countries are rolling out the campaign for booster shots. The goal of our study is to identify and compare the top vaccine concerns in four countries: Canada, Italy, Sweden, and the USA and how these concerns relate to vaccine hesitancy. While most individuals in these countries are now vaccinated, we expect our results to be helpful in guiding vaccination efforts for additional doses, and more in general for other vaccines in the future. We sought to empirically test whether vaccine related concerns followed similar thematic issues in the four countries included in this study, and then to see how these themes related to vaccine hesitancy using data from a cross-sectional survey conducted in May 2021. We applied CFA and created vaccine concern scales for analysis. We then utilized these results in regression-based modeling to determine how concerns related to vaccine hesitancy and whether there were similar or different concerns by country. The results quantitatively highlight that the same vaccine related concerns permeated multiple countries at the same point in time. This implies that COVID-19 vaccination communications could benefit from global collaboration.

Patient-reported outcome measures (PROMs) and palliative-care clinician reported outcomes (ClinROs) mutually improve pain and other symptoms assessment of hospitalized cancer-patients

OBJECTIVES

Patients with malignant diseases are known to have a high symptom burden including pain, and insufficient treatment of pain in this population has been frequently documented. To promote the integration of specialized palliative care and hematology and oncology, this study investigated disease, treatment, and comorbidity related symptoms as well as functional capacity and health-related quality of life (HQoL) by patient-reported outcome measures (PROMs) and clinician-reported outcome measures (ClinROs) among inpatients in a comprehensive cancer center.

METHODS

This cross-sectional study was carried out in a large comprehensive cancer centre of both oncological and hematological inpatients. It combined the use of PROMs and ClinROs.

RESULTS

A high symptom burden was reported with fatigue and appetite loss as the most frequent symptoms, and role function being the most impaired function. Further, a low HQoL score was associated with a high number of symptoms/impairments. More than half of all patients reported pain in the last 24 h. Out of 95 patients with average pain >0 in the last 24 h, 71% were treated with opioids and 24% were treated with adjuvant analgesic (AA) defined as antiepileptics, antidepressants and prednisolone. Out of 57 patients with average pain >0 in the last 24 h and possible neuropathic pain, 33% were treated with AAs. A high odds ratio for moderate/severe pain in patients with possible neuropathic pain mechanisms was observed.

CONCLUSIONS AND IMPLICATIONS

This study did not only emphasize the need for systematic use of PROMs to identify symptoms and needs for inpatients, but also displayed why PROMs supported by ClinROs are a prerequisite to deliver truly individualized and high-quality patient-centered care. This study calls for continuous training of health care professionals to deliver high-quality treatment of pain. Further, it contributes to the growing recognition, that palliative care and standard care must be integrated to strengthen patient-centered care.

Cross-cultural measurement invariance of the Quality of Life Enjoyment and Satisfaction Questionnaire-Short form across ten countries: the application of Bayesian approximate measurement invariance

Background

The Quality of Life Enjoyment and Satisfaction Questionnaire-Short Form (Q-LES-Q-SF) is the most frequently used generic quality of life (QOL) measure in many countries and cultures worldwide. However, no single study has been carried out to investigate whether this questionnaire performs similarly across diverse cultures/countries. Accordingly, this study aimed to assess the cross-cultural measurement invariance of the Q-LES-Q-SF across ten different countries.

Methods

The Q-LES-Q-SF was administrated to a sample of 2822 university students from ten countries: Bangladesh, Brazil, Croatia, India, Nepal, Poland, Serbia, Turkey, the United Arab Emirates, and Vietnam. The Bayesian approximate measurement invariance approach was used to assess the measurement invariance of the Q-LES-Q-SF.

Results

Approximate measurement invariance did not hold across the countries for the Q-LES-Q-SF, with only two out of 14 items being non-invariant; namely items related to doing household and leisure time activities.

Conclusions

Our findings did not support the cross-cultural measurement invariance of the Q-LES-Q-SF; thus, considerable caution is warranted when comparing QOL scores across different countries with this measure. Item rewording and adaptation along with calibrating non-invariant items may narrow these differences and help researchers to create an invariant questionnaire for reliable and valid QOL comparisons across different countries.

Effects of the Heart to Heart Card Game for Patients with Advanced Cancer Receiving Home-Based Palliative Care: A Clinical Randomized Controlled Trial

The Heart to Heart Card Game improves psychological health outcomes in hospitalized patients with advanced cancer, but effectiveness studies for patients at home are rare. This randomized controlled study was conducted to determine the effectiveness of the Heart to Heart Card Game on patients with advanced cancer receiving home-based palliative care. Sixty-six participants were randomly assigned to the intervention group (n = 34) and control group (n = 32). The quality of life, dignity, and psychological distress were considered as outcomes, which were assessed pre-intervention and six weeks after the intervention. There was a statistical difference in the quality of life (global health statues) between the intervention group and the control group after intervention (z = 2.017, p < 0.05). A significant difference was found in the quality of life (emotional, social function), dignity (symptom distress dimension), and psychological distress in the intervention group through intragroup comparison before and after the intervention. This randomized trial showed that the Heart to Heart Card Game likely alleviates barriers to end-of-life conversations and helps patients with advanced cancer maintain a more stable mental state. This trial has been registered at the Chinese Clinical Trial Registry (registration number: ChiCTR2100049933).

Improvement of pain management in a comprehensive cancer center: a comparison of two cross-sectional studies 8 years apart

CONTEXT

In 2011, a multidisciplinary palliative team (MPT) was established at Rigshospitalet (DK) and a cross-sectional study in inpatients was carried out at the Departments of Oncology and Hematology. High symptom burden, high prevalence of pain (64%), and insufficient analgesic treatment were demonstrated. In 2019, a similar study was carried out.

OBJECTIVES

This study compares prevalence of symptoms including pain and analyzes analgesic treatment of adult in-patients in a comprehensive cancer center.

METHODS

Two cross-sectional studies (May-Jun 2011; Feb-Sep 2019).

INCLUSION CRITERIA

malignant diseases, age ≥ 18 y, able to understand Danish. EORTC QLQ-C30 and Brief Pain Inventory (BPI) were applied.

RESULTS

A total of 134 and 183 inpatients were included in 2011 and 2019, respectively. Differences in the two populations were seen; in 2019 more patients had advanced disease (P = 0.0096), lower performance status (P = 0.0028), and a palliative treatment plan (P = 0.0034). The prevalence of impairments and symptoms was high and similar in the 2 years with exception of severe pain (P = 0.0143) and neuropathic pain (P < 0.0001) which increased in 2019. Moreover, pain relief significantly improved, and significantly fewer patients with pain were left untreated. Significant increase in opioid and adjuvant analgesic prescription in 2019.

CONCLUSION

An overall unchanged high symptom burden was observed. However, improvement of pain management was observed in 2019. The establishment of a MPT may possibly have contributed to improved pain management.

Evaluations of the sum-score-based and item response theory-based tests of group mean differences under various simulation conditions

The use of patient-reported outcomes measures is gaining popularity in clinical trials for comparing patient groups. Such comparisons typically focus on the differences in group means and are carried out using either a traditional sum-score-based approach or item response theory (IRT)-based approaches. Several simulation studies have evaluated different group mean comparison approaches in the past, but the performance of these approaches remained unknown under certain uninvestigated conditions (e.g. under the impact of differential item functioning (DIF)). By incorporating some of the uninvestigated simulation features, the current study examines Type I error, statistical power, and effect size estimation accuracy associated with group mean comparisons using simple sum scores, IRT model likelihood ratio tests, and IRT expected-a-posteriori scores. Manipulated features include sample size per group, number of items, number of response categories, strength of discrimination parameters, location of thresholds, impact of DIF, and presence of missing data. Results are summarized and visualized using decision trees.

Assessing measurement invariance in the EORTC QLQ-C30

Purpose

We aimed to investigate measurement invariance (MI) in the European Organisation for research and treatment of cancer quality of life questionnaire core 30 (EORTC QLQ-C30) in a heterogeneous sample of patients with cancer.

Methods

Data from 12 studies within the PROFILES registry were used for secondary analyses (n = 7007). We tested MI by successive restrictions on thresholds, loadings, and intercepts across subgroups based on primary cancer sites, age, sex, time since diagnosis, and life stage, using multigroup confirmatory factor analysis (MGCFA) for ordered categorical measures. We also evaluated the impact of potentially miss-specified parameter equality across groups on latent factor means by releasing threshold and loading equality constraints for each item at a time.

Results

Results showed that the highest level of MI (invariance of thresholds, loadings, and intercepts) was found across groups based on time since diagnosis and life stage and to a lesser extent across groups based on sex, age, and primary tumor site. On item level, however, changes in the item’s associated factor means were relatively small and in most cases canceled each other out to some extent.

Conclusions

Given only a few instances of non-invariance in our study, there is reason to be confident that valid conclusions can be drawn from between-group comparisons of QLQ-C30 latent means as operationalized in our study. Nonetheless, further research into MI between other subgroups for the QLQ-C30 (i.e., treatment effects and ethnicity) is warranted. We stress the importance of including MI evaluations in the development and validation of measurement instruments.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11136-021-02961-8.

Functional impairment, symptom severity, and overall quality of life in patients with advanced lung or colorectal cancer in six European countries: baseline findings from the ACTION study

BACKGROUND

People with advanced cancer often suffer from various symptoms, which can arise from the cancer itself and its treatment, the illness experience, and/or co-morbid conditions. Important patient-reported outcomes such as functional status, symptom severity, and quality of life (QoL) might differ between countries, as countries vary with regard to contextual factors such as their healthcare system.

PURPOSE

To assess self-reported emotional functioning, physical functioning, symptoms, and overall QoL in patients with advanced lung or colorectal cancer from six European countries, particularly in relation to their country of residence.

METHODS

We used baseline patient data from the ACTION trial, including socio-demographic and clinical data as well as patient-reported data regarding functioning, symptoms, and overall QoL (EORTC QLQ-C15-PAL).

RESULTS

Data from 1117 patients (55% lung cancer stage III/IV, 45% colorectal cancer stage IV) were used. The highest (worst) average symptom score was found for fatigue. We found similarities but also important differences in the outcomes across countries. The best scores (the highest for emotional functioning and QoL, the lowest for symptoms) were reported by Dutch and Danish patients. Belgian patients reported relatively low emotional functioning.

CONCLUSION

The optimization of functioning, symptom relief, and overall QoL should be important objectives of healthcare professionals who take care of patients with advanced cancer. There are similarities, but also substantial differences across countries in functional status, symptoms, and overall QoL. Policymakers should take these differences into account and invest in offering health care catered to the needs of their population.

Underlying dimensions of the EORTC QLQ-C30 in a Cuban population of patients with advanced non-small cell lung cancer

BACKGROUND

Quality of Life Core Questionnaire of the European Organization for the Research and Treatment of Cancer (EORTC QLQ-C30) is one of the most used quality of life questionnaires in cancer studies. It provides scores for five functional scales, nine symptom scales, and two single items which assess overall health status and quality of life. However, high correlations among QLQ-C30 items suggest a reduced dimensionality for the scale.

OBJECTIVE

To assess the dimensionality of the EORTC QLQ-C30 using item response theory (IRT) in a training sample and confirmatory factor analysis (CFA) in a test sample.

METHODS

We analyzed responses to QLQ-C30 from 1,107 patients with advanced lung cancer who were included in five clinical trials of immunotherapy. We used non-parametric and parametric IRT models (Mokken, and Samejima's graded response) in a random training set (n = 332) for initial assessment of dimensions and item characteristics of the QLQ-C30. Finally, we used CFA in the test set (n = 775) to confirm the measurement domains.

RESULTS

Mokken model showed that QLQ-C30 fits a unidimensional scale, whereas Samejima model showed that most QLQ-C30 items present adequate difficulty and discrimination. All items showed adequate scalability indexes with an overall scalability of 0.47 (medium scale). The QLQ-C30-reduced dimensionality was confirmed by CFA (comparative fit index = 0.98, root mean square error of approximation = 0.055) with all items presenting factorial loadings > 0.40.

CONCLUSIONS

The EORTC QLQ-C30 fits a unidimensional latent construct identified with perceived quality of life in advanced lung cancer patients.

TRIAL REGISTRATION

RPCEC00000161, RPCEC00000181 and RPCEC00000205.

EORTC QLU-C10D value sets for Austria, Italy, and Poland

Objective

To develop Austrian, Italian, and Polish general population value sets for the EORTC QLU-C10D, a cancer-specific utility instrument based on the EORTC QLQ-C30, and to descriptively compare their index scores for distinct health states.

Methods

The QLU-C10D descriptive system comprises 10 health attributes and each can take on 4 levels. A standardised and pre-tested methodology has been applied for valuations including a web-based discrete choice experiment (DCE). It was administered in 1000 general population respondents per country recruited via online panels, aiming at representativeness for core socio-demographic variables.

Results

In all three countries, the attributes with the largest impact on utility were physical functioning, pain, and role functioning. Cancer-specific dimensions with the largest impact were nausea and fatigue or bowel problems. Utility values of the worst health state (i.e. severe problems on all 10 dimension) were -0.111 (Austria), 0.025 (Italy), and 0.048 (Poland). Country-specific utilities differed for a selection of health states across the continuum. Austrian utilities were systematically lower for moderately and severely impaired health states.

Conclusion

QLU-C10D cancer-specific utilities can now be calculated in three more countries. Differences between countries indicate that careful consideration is required when using non-country-specific value sets in economic evaluations.

Electronic supplementary material

The online version of this article (10.1007/s11136-020-02536-z) contains supplementary material, which is available to authorized users.

Clinical Application of Radioembolization in Hepatic Malignancies: Protocol for a Prospective Multicenter Observational Study

Background

Radioembolization, also known as transarterial radioembolization or selective internal radiation therapy with yttrium-90 (90Y) resin microspheres, is an established treatment modality for patients with primary and secondary liver tumors. However, large-scale prospective observational data on the application of this treatment in a real-life clinical setting is lacking.

Objective

The main objective is to collect data on the clinical application of radioembolization with 90Y resin microspheres to improve the understanding of the impact of this treatment modality in its routine practice setting.

Methods

Eligible patients are 18 years or older and receiving radioembolization for primary and secondary liver tumors as part of routine practice, as well as have signed informed consent. Data is collected at baseline, directly after treatment, and at every 3-month follow-up until 24 months or study exit. The primary objective of the Cardiovascular and Interventional Radiological Society of Europe Registry for SIR-Spheres Therapy (CIRT) is to observe the clinical application of radioembolization. Secondary objectives include safety, effectiveness in terms of overall survival, progression-free survival (PFS), liver-specific PFS, imaging response, and change in quality of life.

Results

Between January 2015 and December 2017, 1047 patients were included in the study. The 24-month follow-up period ended in December 2019. The first results are expected in the third quarter of 2020.

Conclusions

The CIRT is the largest observational study on radioembolization to date and will provide valuable insights to the clinical application of this treatment modality and its real-life outcomes.

Trial Registration

ClinicalTrials.gov NCT02305459; https://clinicaltrials.gov/ct2/show/NCT02305459

International Registered Report Identifier (IRRID)

DERR1-10.2196/16296

Evaluating the cross-cultural validity of three family quality of life sub-scales

BACKGROUND

Families of children with disabilities often face unique challenges. Developed in a U.S. context, the Beach Center Family Quality of Life measure assesses the effectiveness of supports and services that families receive. This study examines whether items from three sub-scales of the Beach Center instrument perform similarly for two samples, one from Lusaka, Zambia, and the second from a Midwestern U.S. state.

METHODS

This cross-sectional research used secondary data and completed hierarchical ordinal regression analyses on item-level performance within the sub-scales.

RESULTS

Only one item flagged for potential item bias with remaining items performing similarly when controlling for overall sub-scale scores.

CONCLUSIONS

This study extends existing research on the cultural and linguistic appropriateness of the Beach Center measure, providing additional validity evidence about the internal structure of the scales. Findings indicate that these items are acceptable outcome measures for policy and programme evaluations in Zambia.

The Effects of Diet and Dietary Interventions on the Quality of Life among Breast Cancer Survivors: A Cross-Sectional Analysis and a Systematic Review of Experimental Studies

There is an ongoing need for solid evidence about the effects of healthy behaviors, and particularly diet, on the quality of life (QoL) among breast cancer survivors. We first conducted a cross-sectional study on 68 Italian stage I-III breast cancer survivors, to investigate the association of adherence to the Mediterranean diet (MD), physical activity and weight status with QoL. Adherence to MD and physical activity was assessed using structured questionnaires. QoL was assessed using the European Organization for the Research and Treatment of Cancer Quality-of-Life tools. We showed that low consumption of red meat and carbonated beverages, daily consumption of wine and high consumption of dishes seasoned with sofrito had beneficial effects on several QoL subscales. By contrast, using olive oil as the main culinary fat, low consumption of commercial sweets and high consumption of nuts were associated with negative effects. Overall, these findings resulted in a null effect of adherence to MD on QoL. Furthermore, we observed better QoL sub-scores among women who performed moderate physical activity (i.e., diarrhea) and those who were underweight/normal weight (i.e., physical functioning and dyspnea) if compared with their counterparts (p-values ≤ 0.003 after correction for multiple comparison). Next, we performed a systematic review of nine experimental studies to summarize whether dietary interventions might improve QoL among breast cancer patients. All the studies demonstrated significant improvements in overall QoL and/or its subscales after the interventions. However, differences in study design, interventions and tools used for QoL assessment did not allow us to provide an overall estimate. Moreover, only a single-arm trial evaluated the effect of an exclusive dietary-based intervention, while others combined dietary recommendations with physical activity and weight loss programs. For these reasons, our study encourages more efforts to improve the robustness of current evidence, through more homogenous tools, larger population-based studies and further randomized controlled trials.

Dimensionality and Measurement Invariance of the Italian Version of the EORTC QLQ-C30 in Postoperative Lung Cancer Patients

Background

This study aims to validate and evaluate the psychometric properties and measurement invariance of the Italian version of the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Core 30 (QLQ-C30), which is a measure of quality of life (QoL) for lung cancer patients after surgery.

Methods

A total of 167 lung cancer patients completed the Italian version of the EORTC QLQ-C30 questionnaire at 30 days after they received a lobectomy. The factor structure of this scale was assessed by performing confirmatory factor analysis (CFA). Measurement invariance was evaluated by considering differential item functioning (DIF) due to age, gender, and type of surgery (i.e., robot- or not robot-assisted).

Results

The CFA demonstrated the validity of the factor structure of the EORTC QLQ-C30 in assessing overall health and eight distinct subscales of adverse events and functioning. Moreover, the results highlighted a minimal DIF with only trivial consequences on measurement invariance. Specifically, the DIF did not affect the mean differences of latent scores of QoL between patients undergoing robot-assisted surgery or traditional surgery.

Conclusion

These findings supported the validity and suitability of the EORTC QLQ-C30 for the assessment of QoL in lung cancer patients of diverse ages and genders undergoing lobectomy with or without robot-assisted surgery.

Patient-reported outcomes with durvalumab after chemoradiotherapy in stage III, unresectable non-small-cell lung cancer (PACIFIC): a randomised, controlled, phase 3 study

BACKGROUND

In the ongoing, phase 3 PACIFIC trial, durvalumab improved the primary endpoints of progression-free survival and overall survival compared with that for placebo, with similar safety, in patients with unresectable, stage III non-small-cell lung cancer. In this analysis, we aimed to evaluate one of the secondary endpoints, patient-reported outcomes (PROs).

METHODS

PACIFIC is an ongoing, international, multicentre, double-blind, randomised, controlled, phase 3 trial. Eligible patients were aged at least 18 years, had a WHO performance status of 0 or 1, with histologically or cytologically documented stage III, unresectable non-small-cell lung cancer, for which they had received at least two cycles of platinum-based chemoradiotherapy, with no disease progression after this treatment. We randomly assigned patients (2:1) using an interactive voice response system and a blocked design (block size=3) stratified by age, sex, and smoking history to receive 10 mg/kg intravenous durvalumab or matching placebo 1-42 days after concurrent chemoradiotherapy, then every 2 weeks up to 12 months. The primary endpoints of progression-free survival and overall survival have been reported previously. PROs were a prespecified secondary outcome. We assessed PRO symptoms, functioning, and global health status or quality of life in the intention-to-treat population with the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Core 30 (QLQ-C30) version 3 and its lung cancer module, the Quality of Life Questionnaire-Lung Cancer 13 (QLQ-LC13) at the time of random allocation to groups, at weeks 4 and 8, every 8 weeks until week 48, and then every 12 weeks until progression. Changes from baseline to 12 month in key symptoms were analysed with mixed model for repeated measures (MMRM) and time-to-event analyses. A 10-point or greater change from baseline (deterioration or improvement) was deemed clinically relevant. This study is registered with ClinicalTrials.gov, NCT02125461, and EudraCT, 2014-000336-42.

FINDINGS

Between May 9, 2014, and April 22, 2016, 476 patients were assigned to receive durvalumab, and 237 patients were assigned to receive placebo. As of March 22, 2018, the median follow-up was 25·2 months (IQR 14·1-29·5). More than 79% of patients given durvalumab and more than 82% of patients given placebo completed questionnaires up to week 48. Between baseline and 12 months, the prespecified longitudinal PROs of interest, cough (MMRM-adjusted mean change 1·8 [95% CI 0·06 to 3·54] in the durvalumab group vs 0·7 [-1·91 to 3·30] in the placebo group), dyspnoea (3·1 [1·75 to 4·36] vs 1·4 [-0·51 to 3·34]), chest pain (-3·1 [-4·57 to -1·60] vs -3·5 [-5·68 to -1·29]), fatigue (-3·0 [-4·53 to -1·50] vs -5·2 [-7·45 to -2·98]), appetite loss (-5·8 [-7·28 to -4·36] vs -7·0 [-9·17 to -4·87]), physical functioning (0·1 [-1·10 to 1·28] vs 2·0 [0·22 to 3·73]), and global health status or quality of life (2·6 [1·21 to 3·94] vs 1·8 [-0·25 to 3·81]) remained stable with both treatments, with no clinically relevant changes from baseline. The between-group differences in changes from baseline to 12 months in cough (difference in adjusted mean changes 1·1, 95% CI -1·89 to 4·11), dyspnoea (1·6, -0·58 to 3·87), chest pain (0·4, -2·13 to 2·93), fatigue (2·2, -0·38 to 4·78), appetite loss (1·2, -1·27 to 3·67), physical functioning (-1·9, -3·91 to 0·15), or global health status or quality of life (0·8, -1·55 to 3·14) were not clinically relevant. Generally, there were no clinically important between-group differences in time to deterioration of prespecified key PRO endpoints.

INTERPRETATION

Our findings suggest that a clinical benefit with durvalumab can be attained without compromising PROs. This result is of note because the previous standard of care was observation alone, with no presumed detriment to PROs.

FUNDING

AstraZeneca.

Translation and cultural adaptation of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Lung Cancer Module for quality of life assessment in patients with lung cancer in Brazil

OBJECTIVE

To translate the European Organisation for Research and Treatment of Cancer (EORTC) 29-item Quality of Life Questionnaire-Lung Cancer Module (QLQ-LC29, developed for the assessment of quality of life in patients with lung cancer) to Portuguese, conducting a pilot study of the Portuguese-language version and adapting it for use in Brazil.

METHODS

For the translation, cultural adaptation, and pilot testing of the QLQ-LC29, we followed the guidelines established by the EORTC. The translation (English → Portuguese) and back-translation (Portuguese → English) were both carried out by translators, working independently, who were native speakers of one language and fluent in the other. After review, a draft version was created for pilot testing in lung cancer patients in Brazil.

RESULTS

A total of 15 patients diagnosed with lung cancer completed the Portuguese-language version of the questionnaire. At the end of the process, we conducted a structured interview to identify any patient difficulty in understanding any of the questions. The final versions were sent to the EORTC and were approved.

CONCLUSIONS

The Portuguese-language version of the EORTC QLQ-LC29 appears to be a useful, important, reliable questionnaire that is a valid tool for assessing quality of life in patients with lung cancer in Brazil.

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.

Patient-Reported Symptoms and Impact of Treatment With Osimertinib Versus Chemotherapy in Advanced Non-Small-Cell Lung Cancer: The AURA3 Trial

Purpose Capturing patient-reported outcome data is important for evaluating the overall clinical benefits of new cancer therapeutics. We assessed self-reported symptoms of advanced non-small-cell lung cancer in patients treated with osimertinib or chemotherapy in the AURA3 phase III trial. Patients and Methods Patients completed the European Organisation for Research and Treatment of Cancer 13-item Quality of Life Questionnaire-Lung Cancer Module (EORTC QLQ-LC13) questionnaire on disease-specific symptoms and the EORTC 30-item Core Quality of Life Questionnaire (EORTC QLC-C30) on general cancer symptoms, functioning, global health status/quality of life. We assessed differences between treatments in time to deterioration of individual symptoms and odds of improvement (a deterioration or improvement was defined as a change in score from baseline of ≥ 10). Hazard ratios (HRs) were calculated using a log-rank test stratified by ethnicity; odds ratios (ORs) were assessed using logistic regression adjusted for ethnicity. Results At baseline, the questionnaires were completed by 82% to 88% of patients, and 30% to 70% had individual key symptoms. Time to deterioration was longer with osimertinib than with chemotherapy for cough (HR, 0.74; 95% CI, 0.53 to 1.05), chest pain (HR, 0.52; 95% CI, 0.37 to 0.73), and dyspnea (HR, 0.42; 95% CI, 0.31 to 0.58). The proportion of symptomatic patients with improvement in global health status/quality of life was higher with osimertinib (80 [37%] of 215) than with chemotherapy (23 [22%] of 105; OR, 2.11; 95% CI, 1.24 to 3.67; P = .007). Proportions were also higher for appetite loss (OR, 2.50; 95% CI, 1.31 to 4.84) and fatigue (OR, 1.96; 95% CI, 1.20 to 3.22). Conclusion Time to deterioration of key symptoms was longer with osimertinib than with chemotherapy, and a higher proportion of patients had improvement in global health status/quality of life, demonstrating improved patient outcomes with osimertinib.

An exploration of differences between Japan and two European countries in the self-reporting and valuation of pain and discomfort on the EQ-5D

PURPOSE

To investigate the systematic differences in the self-reporting and valuation of overall health and, in particular, pain/discomfort between three countries (England/UK, Japan, and Spain) on the EQ-5D.

METHODS

Existing datasets were used to explore differences in responses on the EQ-5D descriptive system between Japan (3L and 5L), the UK (3L), England (5L), and Spain (5L), particularly on the dimension of pain/discomfort. The role of different EQ dimensions in determining self-reported overall health scores for the EuroQol visual analog scale (EQ-VAS) was investigated using ordinary least squares regression. Time trade-off (TTO) results from Japanese and UK respondents for the EQ-5D-3L as well as Japanese and English respondents for the EQ-5D-5L were compared using t tests.

RESULTS

For the EQ-5D-3L, a higher percentage of respondents in Japan than in the UK reported 'no pain/discomfort' (81.6 vs 67.0%, respectively); for the EQ-5D-5L, the proportions were 79.2% in Spain, 73.2% in Japan, and 63-64% in England, after adjusting for age differences in samples. The 'pain/discomfort' dimension had the largest impact on respondents' self-reported EQ-VAS only for EQ-5D-3L in Japan. Using the EQ-5D-3L, Japanese respondents were considerably less willing to trade off time to avoid pain/discomfort than the UK respondents; for example, moving from health state, 11121 (some problems with pain/discomfort) to 11131 (extreme pain/discomfort) represented a decrement of 0.65 on the observed TTO value in the UK compared with 0.15 in Japan. Using the EQ-5D-5L, Japanese respondents were also less willing to trade off time to avoid pain/discomfort than respondents in England; however, the difference in values was much smaller than that observed using EQ-5D-3L data.

CONCLUSIONS

This study provides evidence of between-country differences in the self-reporting and valuation of health, including pain/discomfort, when using EQ-5D in general population samples. The results suggest a need for caution when comparing or aggregating EQ-5D self-reported data in multi-country studies.

The use of EORTC measures in daily clinical practice-A synopsis of a newly developed manual

Cancer has increasingly become a chronic condition and the routine collection of patient-reported outcomes (PROs) like quality of life is widely recommended for clinical practice. Nonetheless, the successful implementation of PROs is still a major challenge, although common barriers to and facilitators of their beneficial use are well known. To support health care professionals and other stakeholders in the implementation of the EORTC PRO measures, the EORTC Quality of Life Group provides guidance on issues considered important for their use in daily clinical practice. Herein, we present an outline of the newly developed "'Manual for the use of EORTC measures in daily clinical practice", covering the following issues: * a rationale for using EORTC measures in routine care *selection of EORTC measures, timing of assessments, scoring and presentation of results * aspects of a strategic implementation * electronic data assessment and telemonitoring, and * further use of EORTC measures and ethical considerations. Next to an extensive overview of currently available literature, the manual specifically focuses on knowledge about EORTC measures to give evidence-based recommendations whenever possible and to encourage readers and end-users of EORTC measures to contribute to further needed high-quality research. The manual will be accessible on the EORTC Quality of Life Group website's homepage and will be periodically updated to take into account any new knowledge due to medical, technical, regulatory and scientific advances.

Pooling of cross-cultural PRO data in multinational clinical trials: how much can poor measurement affect statistical power?

AIMS

Cultural differences and/or poor linguistic validation of patient-reported outcome (PRO) instruments may result in differences in the assessment of the targeted concept across languages. In the context of multinational clinical trials, these measurement differences may add noise and potentially measurement bias to treatment effect estimation. Our objective was to explore the potential effect on treatment effect estimation of the "contamination" of a cultural subgroup by a flawed PRO measurement.

METHODS

We ran a simulation exercise in which the distribution of the score in the overall sample was considered a mixture of two normal distributions: a standard normal distribution was assumed in a "main" subgroup and a normal distribution which differed either in mean (bias) or in variance (noise) in a "contaminated" subgroup (the subgroup with potential flaws in the PRO measurement). The observed power was compared to the expected power (i.e., the power that would have been observed if the subgroup had not been contaminated).

RESULTS

Even if differences between the expected and observed power were small, some substantial differences were obtained (up to a 0.375 point drop in power). No situation was systematically protected against loss of power.

CONCLUSION

The impact of poor PRO measurement in a cultural subgroup may induce a notable drop in the study power and consequently reduce the chance of showing an actual treatment effect. These results illustrate the importance of the efforts to optimize conceptual and linguistic equivalence of PRO measures when pooling data in international clinical trials.

Loss of muscle mass in the end of life in patients with advanced cancer

PURPOSE

Muscle mass depletion is associated with adverse outcomes in cancer patients. There is limited information on the impact of age, sex, tumor type, and inflammation on muscle loss in the end of life of cancer patients.

METHODS

Muscle depletion and loss of muscle in the last 2 years of life was estimated in 471 cancer patients from 779 dual-energy X-ray absorptiometry scans. A linear mixed model was used to estimate the impact of age, sex, tumor type, and inflammation.

RESULTS

Patients above median age (>71 years) had less muscle mass (-1.1 ± 0.3 kg, P < 0.001). Prevalence of muscle depletion was higher in men than women (59 vs. 28%, P < 0.001). Men lost muscle mass over time (mean, 1.4 ± 0.3 kg/year, P < 0.001) contrary to women (0.3 ± 0.4 kg/year, P = 0.5). Patients with pancreatic cancer had less muscle mass than patients with biliary tract and colorectal cancers (P < 0.02). There were no differences in muscle loss over time in patients grouped by median age or tumor type. The prevalence of elevated C-reactive protein was 61 to 70% during the study. Patients with C-reactive protein >10 mg/L had less muscle mass (0.6 ± 0.2 kg, P < 0.001) and lost muscle mass at an accelerated pace during the disease trajectory (0.7 ± 0.3 kg/year, P = 0.03).

CONCLUSIONS

Muscle loss in advanced cancer is related to age, sex, tumor type, and inflammation. The mechanism(s) behind the apparent sexual dimorphism warrants further study.

Using quantitative methods within the Universalist model framework to explore the cross-cultural equivalence of patient-reported outcome instruments

PURPOSE

The cross-cultural equivalence of patient-reported outcome (PRO) instruments is critical when they are used in international settings. The Universalist model of equivalence was proposed as a framework to investigate cross-cultural equivalence. The purpose of this paper was to illustrate how quantitative methods can be used to investigate cross-cultural equivalence within this framework.

METHODS

The six types of equivalence of the Universalist model were reviewed from a statistical perspective and statistical techniques allowing addressing the underlying question were identified. These methods are described and examples are provided of how they can be applied. An integrated pragmatic approach to the exploration of cross-cultural equivalence was developed based on these methods.

RESULTS

The statistical techniques identified were factor analysis to explore conceptual equivalence, differential item functioning to explore semantic and item equivalence, and comparison of measurement properties for the measurement equivalence. The statistical techniques addressing operational equivalence were found to be diverse and highly specific to the operational aspect under investigation. Functional equivalence involves a comprehensive appraisal of the potential impact of the results of the other equivalences on the conclusions of the research. This structured appraisal of functional equivalence offers a framework for a comprehensive, but flexible, approach for the efficient application of statistical analyses to explore cross-cultural equivalence of PRO instruments.

CONCLUSION

The different types of equivalence of the Universalist model can be investigated using quantitative methods. An integrated approach, which could be used in a variety of settings, was developed to allow the whole notion of cross-cultural equivalence to be comprehensively and efficiently addressed.

Pain characteristics and management of inpatients admitted to a comprehensive cancer centre: a cross-sectional study

AIMS

This prospective, cross-sectional study aimed to assess cancer pain and its management in an inpatient setting at a comprehensive cancer centre in Denmark.

METHODS

One hundred and eighty-eight inpatients with cancer were invited to participate (May/June 2011). Demographics, diagnoses, World Health Organization performance status, health-related quality of life, pain and data regarding analgesic treatment were registered.

RESULTS

One hundred and thirty-four (71.3%) patients agreed to participate in the study. Most frequent diagnoses were leukaemia (27.6%) and lung cancer (14.2%). A high prevalence of pain was observed, 65.7%. Thirty-two per cent reported moderate to severe pain when it was at its worst, 96% reported no or mild pain when it was at its least. Nearly 22% reported moderate to severe pain when the pain was categorised as average. Breakthrough pain episodes were reported by 30.5%. Adjuvant medication was sparsely used and not always correctly indicated. Out of 88 patients with pain, 62.5% were left untreated according to the Electronic Medication System. Higher health-related quality of life was associated with lower pain intensity. The use of opioids with or without adjuvants was associated with higher pain intensity and higher number of breakthrough pain episodes.

CONCLUSIONS

Approximately two thirds of inpatients reported pain and one third had breakthrough pain. A substantial number of patients with pain were left untreated. Opioid-treated patients reported highest pain intensity and number of breakthrough episodes; however, analgesic medication seemed to be underused. Measures to improve pain assessment and management are highly required.

Comparing higher order models for the EORTC QLQ-C30

PURPOSE

To investigate the statistical fit of alternative higher order models for summarizing the health-related quality of life profile generated by the EORTC QLQ-C30 questionnaire.

METHODS

A 50% random sample was drawn from a dataset of more than 9,000 pre-treatment QLQ-C30 v 3.0 questionnaires completed by cancer patients from 48 countries, differing in primary tumor site and disease stage. Building on a "standard" 14-dimensional QLQ-C30 model, confirmatory factor analysis was used to compare 6 higher order models, including a 1-dimensional (1D) model, a 2D "symptom burden and function" model, two 2D "mental/physical" models, and two models with a "formative" (or "causal") formulation of "symptom burden," and "function."

RESULTS

All of the models considered had at least an "adequate" fit to the data: the less restricted the model, the better the fit. The RMSEA fit indices for the various models ranged from 0.042 to 0.061, CFI's 0.90-0.96, and TLI's from 0.96 to 0.98. All chi-square tests were significant. One of the Physical/Mental models had fit indices superior to the other models considered.

CONCLUSIONS

The Physical/Mental health model had the best fit of the higher order models considered, and enjoys empirical and theoretical support in comparable instruments and applications.

An evaluation of the response category translations of the EORTC QLQ-C30 questionnaire

PURPOSE

The aim of this study was to evaluate the translated response categories used in eight translations of the European Organisation for Research and Treatment of Cancer QLQ-C30 questionnaire, which is used in many international clinical trials. Twenty-eight of the 30 items in the questionnaire have the same four response categories: "Not at all", "A little", "Quite a bit" and "Very Much".

METHODS

People with knowledge of both English and one of eight European languages were asked to complete an Internet survey. The strength (intensity) of the translated categories was assessed using two separate approaches: one using a verbal response scale and the other a visual analogue scale (VAS).

RESULTS

Two hundred and seventy-nine people participated in the survey. Most translations were rated similarly to English. The largest differences were for the German translation of "Quite a bit", which was rated 16.3 points lower than the corresponding English category on a 0-100 VAS.

CONCLUSIONS

Most of the translated categories were found to be similar to the English versions and should continue to be used. We recommend that three translated categories should be considered for revision. Similar surveys could be used to assess the categories used in other translated quality of life instruments.

Assessing measurement invariance of a health-related quality-of-life questionnaire in radiotherapy patients

Objective

If the assumption of measurement invariance is not tested, we cannot be sure whether differences observed are due to true differences in health-related quality-of-life (HRQoL), or are measurement artifacts. We aim to investigate this assumption in a sample of heterogeneous cancer patients, focusing on whether age, sex, previous treatment for cancer, and information regarding treatment preferences result in biased HRQoL scores.

Methods

155 cancer patients who were about to begin their first session of radiotherapy were included. HRQoL was measured using the EORTC QLQ-C30. Structural equation modeling was applied to assess whether there was a violation of the assumption of invariance.

Results

A satisfactory single construct (Functioning HRQoL) measurement model was found and two violations of invariance were identified. Irrespective of patients’ Functioning HRQoL, older patients reported worse physical functioning and patients who had received treatment prior to radiotherapy reported worse emotional functioning than we would otherwise expect.

Conclusions

In the present study, accounting for measurement bias lead to a substantial improvement in the overall fit of the model. By ignoring the bias, we would have concluded that the model fit was unsatisfactory. The findings underline the importance of investigating measurement invariance in scales designed for heterogeneous samples.

Multiple, correlated covariates associated with differential item functioning (DIF): Accounting for language DIF when education levels differ across languages

Differential item functioning (DIF) occurs when a test item has different statistical properties in subgroups, controlling for the underlying ability measured by the test. DIF assessment is necessary when evaluating measurement bias in tests used across different language groups. However, other factors such as educational attainment can differ across language groups, and DIF due to these other factors may also exist. How to conduct DIF analyses in the presence of multiple, correlated factors remains largely unexplored. This study assessed DIF related to Spanish versus English language in a 44-item object naming test. Data come from a community-based sample of 1,755 Spanish- and English-speaking older adults. We compared simultaneous accounting, a new strategy for handling differences in educational attainment across language groups, with existing methods. Compared to other methods, simultaneously accounting for language- and education-related DIF yielded salient differences in some object naming scores, particularly for Spanish speakers with at least 9 years of education. Accounting for factors that vary across language groups can be important when assessing language DIF. The use of simultaneous accounting will be relevant to other cross-cultural studies in cognition and in other fields, including health-related quality of life.

Interpretation of differential item functioning analyses using external review

Differential item functioning (DIF) analyses are used to determine whether certain groups respond differently to a particular item of a test or questionnaire; however, these do not explain the reasons for observed response differences. Many studies have used external reviews of items, sometimes using blinded reviewers, to help interpret these results. The authors conducted a literature review of this topic to describe the current usage of external reviews alongside DIF analyses. It concentrated on studies of health-related quality of life instruments, but studies in other fields were also considered. Relatively few examples of blinded item reviews were identified, and these were mostly from educational studies. A case study using blinded bilingual reviewers alongside translation DIF analyses of a health-related quality of life instrument is described. Future researchers should consider conducting external item reviews alongside DIF analyses.

Differential item functioning (DIF) analyses of health-related quality of life instruments using logistic regression

BACKGROUND

Differential item functioning (DIF) methods can be used to determine whether different subgroups respond differently to particular items within a health-related quality of life (HRQoL) subscale, after allowing for overall subgroup differences in that scale. This article reviews issues that arise when testing for DIF in HRQoL instruments. We focus on logistic regression methods, which are often used because of their efficiency, simplicity and ease of application.

METHODS

A review of logistic regression DIF analyses in HRQoL was undertaken. Methodological articles from other fields and using other DIF methods were also included if considered relevant.

RESULTS

There are many competing approaches for the conduct of DIF analyses and many criteria for determining what constitutes significant DIF. DIF in short scales, as commonly found in HRQL instruments, may be more difficult to interpret. Qualitative methods may aid interpretation of such DIF analyses.

CONCLUSIONS

A number of methodological choices must be made when applying logistic regression for DIF analyses, and many of these affect the results. We provide recommendations based on reviewing the current evidence. Although the focus is on logistic regression, many of our results should be applicable to DIF analyses in general. There is a need for more empirical and theoretical work in this area.

Impact of cultural and linguistic factors on symptom reporting by patients with cancer

BACKGROUND

Patient reporting of the severity and impact of symptoms is an essential component of cancer symptom management and cancer treatment clinical trials. In multinational clinical trials, cultural and linguistic variations in patient-reported outcomes instruments could confound the interpretation of study results.

METHODS

The severity and interference of multiple symptoms in 1433 cancer patients with mixed diagnoses and treatment status from the United States, China, Japan, Russia, and Korea were measured with psychometrically validated language versions of the M. D. Anderson Symptom Inventory (MDASI). Mixed-effect ordinal probit regression models were fitted to the pooled data to compare the magnitude of the effect of "country" (nation and linguistic factors) with between-subjects effects on symptom reporting, adjusted for patient and clinical factors (age, sex, performance status, and chemotherapy status).

RESULTS

For the pooled sample, fatigue, disturbed sleep, distress, pain, and lack of appetite were the most severe patient-reported MDASI symptoms. The magnitude of the variance of the country random effects was only one-fourth to one-half of the interpatient variation (sigma(2) = 0.23-0.46) for all symptoms, except nausea and vomiting.

CONCLUSIONS

Cultural and linguistic variations in symptom reporting among the five language versions of the validated MDASI were limited. Ordinal probit modeling provided a simple mechanism for accounting for cultural and linguistic differences in patient populations. The equivalence among MDASI translations in this study suggests that symptom ratings collected from various cultural and language groups using the MDASI can be interpreted in a similar way in oncology practice, clinical trials, and clinical research.

Satisfactory cross-cultural validity of the ACTG symptom distress module in HIV-1-infected antiretroviral-naive patients

BACKGROUND

Multinational clinical trials commonly include different language versions of patient-reported outcomes (PRO) instruments without considering the question of their cross-cultural validity. The inclusion of a PRO instrument, the Adult AIDS Clinical Trial Group Symptom Distress Module (SDM), in an multinational clinical trial in HIV-1 antiretroviral-naive patients offered an opportunity to explore the methods to assess cross-cultural validity of PRO instruments in the context of clinical trials.

PURPOSE

To assess the cross-cultural validity of the SDM across seven cultural groups in the setting of a multinational HIV clinical trial.

METHODS

Twenty-five language versions of the SDM were included in a Phase IIb/III trial comparing maraviroc with efavirenz (each in combination with zidovudine/ lamivudine) conducted in 12 countries to assess symptoms perceived by HIV-1-infected antiretroviral-naive patients. Differential item functioning (DIF) detection and the STATIS method were combined in a pragmatic approach to assess the cross-cultural validity of the SDM using pre-antiretroviral treatment data from 759 patients.

RESULTS

Statistically significant DIF between cultural groups was observed for four items: fatigue; fevers; anxiety; and headache. However, examination of these items by linguists did not lead to meaningful explanations for the statistical differences. With the STATIS approach, the Bantu and European Germanic groups were the furthest from the Occidental English group.

LIMITATIONS

The assessment of cross-cultural validity had to be performed on some very small samples and on data aggregated by cultural groups, which suggests the need for a cautious interpretation of the results.

CONCLUSIONS

Given the heterogeneity of cultures considered, the absence of meaningful explanations for statistically significant differences between cultural groups supports the cross-cultural validity of the SDM versions included in this trial. Thus, this study demonstrated that it is feasible to conduct assessment of crosscultural validity of PRO instruments using data collected in the setting of multinational clinical trials.

The practical impact of differential item functioning analyses in a health-related quality of life instrument

INTRODUCTION

Differential item functioning (DIF) analyses are commonly used to evaluate health-related quality of life (HRQoL) instruments. There is, however, a lack of consensus as to how to assess the practical impact of statistically significant DIF results.

METHODS

Using our previously published ordinal logistic regression DIF results for the Fatigue scale of a HRQoL instrument as an example, the practical impact on a particular Norwegian clinical trial was investigated. The results were used to determine the difference in mean Fatigue scores assuming that the same trial was conducted in the UK. The results were then compared with published information on what would be considered a clinically important change in scores.

RESULTS

The item with the largest DIF effect resulted in differences between the mean English and Norwegian Fatigue scores that, although small, could be considered clinically important. Sensitivity analyses showed that larger differences were found for shorter scales, and when the proportions in each response category were equal.

DISCUSSION

Our scenarios suggest that translation differences in an item can result in small, but clinically important, differences at the scale score level. This is more likely to be problematic for observational studies than for clinical trials, where randomised groups are stratified by centre.

Multinational trials-recommendations on the translations required, approaches to using the same language in different countries, and the approaches to support pooling the data: the ISPOR Patient-Reported Outcomes Translation and Linguistic Validation Good Research Practices Task Force report

OBJECTIVES

With the internationalization of clinical trial programs, there is an increased need to translate and culturally adapt patient-reported outcome (PRO) measures. Although guidelines for good practices in translation and linguistic validation are available, the ISPOR Patient-Reported Outcomes Translation and Linguistic Validation Task Force identified a number of areas where they felt that further discussion around methods and best practices would be beneficial. The areas identified by the team were as follows: 1) the selection of the languages required for multinational trials; 2) the approaches suggested when the same language is required across two or more countries; and 3) the assessment of measurement equivalence to support the aggregation of data from different countries.

METHODS

The task force addressed these three areas, reviewed the available literature, and had multiple discussions to develop this report.

RESULTS

Decision aid tools have also been developed and presented for the selection of languages and the approaches suggested for the use of the same language in different countries.

CONCLUSION

It is hoped that this report and the decision tools proposed will assist those involved with multinational trials to 1) decide on the translations required for each country; 2) choose the approach to use when the same language is spoken in more than one country; and 3) choose methods to gather evidence to support the pooling of data collected using different language versions of the same tool.

Differential item functioning (DIF) in the EORTC QLQ-C30: a comparison of baseline, on-treatment and off-treatment data

INTRODUCTION

Differential item functioning (DIF) analyses can be used to explore translation, cultural, gender or other differences in the performance of quality of life (QoL) instruments. These analyses are commonly performed using "baseline" or pretreatment data. We previously reported DIF analyses to examine the pattern of item responses for translations of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 QoL instrument, using only data collected prior to cancer treatment. We now compare the consistency of these results with similar analyses of on-treatment and off-treatment assessments and explore whether item relationships differ from those at baseline.

METHODS

Logistic regression DIF analyses were used to examine the translation of each item in each multi-item scale at the three time points, after controlling for the overall scale score and other covariates. The consistency of results at the three time points was explored.

RESULTS

For most EORTC QLQ-C30 subscales, the DIF results were very consistent across the three time points. Results for the Nausea and Vomiting scale varied the most across assessments.

DISCUSSION

The results indicated that DIF analyses were stable across each time point and that the same DIF effects were usually found regardless of the treatment status of the respondent.

Japanese-English language equivalence of the Cognitive Abilities Screening Instrument among Japanese-Americans

BACKGROUND

The Cognitive Abilities Screening Instrument (CASI) was designed for use in cross-cultural studies of Japanese and Japanese-American elderly in Japan and the U.S.A. The measurement equivalence in Japanese and English had not been confirmed in prior studies.

METHODS

We analyzed the 40 CASI items for differential item functioning (DIF) related to test language, as well as self-reported proficiency with written Japanese, age, and educational attainment in two large epidemiologic studies of Japanese-American elderly: the Kame Project (n=1708) and the Honolulu-Asia Aging Study (HAAS; n = 3148). DIF was present if the demographic groups differed in the probability of success on an item, after controlling for their underlying cognitive functioning ability.

RESULTS

While seven CASI items had DIF related to language of testing in Kame (registration of one item; recall of one item; similes; judgment; repeating a phrase; reading and performing a command; and following a three-step instruction), the impact of DIF on participants' scores was minimal. Mean scores for Japanese and English speakers in Kame changed by <0.1 SD after accounting for DIF related to test language. In HAAS, insufficient numbers of participants were tested in Japanese to assess DIF related to test language. In both studies, DIF related to written Japanese proficiency, age, and educational attainment had minimal impact.

CONCLUSIONS

To the extent that DIF could be assessed, the CASI appeared to meet the goal of measuring cognitive function equivalently in Japanese and English. Stratified data collection would be needed to confirm this conclusion. DIF assessment should be used in other studies with multiple language groups to confirm that measures function equivalently or, if not, form scores that account for DIF.

Modified WHODAS-II provides valid measure of global disability but filter items increased skewness

OBJECTIVE

The WHODAS-II was substantially modified for use in the World Mental Health Surveys. This article considers psychometric properties and implications of filter items used to reduce respondent burden of the modified WHODAS-II.

STUDY DESIGN AND SETTING

Seventeen surveys in 16 countries administered a modified WHODAS-II to population samples (N=38,934 adults). Modifications included introducing filter questions for four subscales and substituting questions on the number of days activity was limited for the Life Activities domain. We evaluated distributional properties, reliability, and validity of the modified WHODAS-II.

RESULTS

Most respondents (77%-99%) had zero scores on filtered subscales. Lower bound estimates of internal consistency (alpha) for the filtered subscales were typically in the 0.70s, but were higher for the Global scale. Loadings of subscale scores on a Global Disability factor were moderate to high. Correlations with the Sheehan Disability Scale were modest but consistently positive, while correlations with SF-12 Physical Component Summary were considerably higher. Cross-national variability in disability scores was observed, but was not readily explainable.

CONCLUSIONS

Internal consistency and validity of the modified WHODAS-II was generally supported, but use of filter questions impaired measurement properties. Group differences in modified WHODAS-II disability scores may be compared within, but not necessarily across, countries.

Translation procedures for standardised quality of life questionnaires: The European Organisation for Research and Treatment of Cancer (EORTC) approach

BACKGROUND

The European Organisation for Research and Treatment of Cancer quality of life (EORTC QL) questionnaires are used in international trials and therefore standardised translation procedures are required. This report summarises the EORTC translation procedure, recent accomplishments and challenges.

METHODS

Translations follow a forward-backward procedure, independently carried out by two native-speakers of the target language. Discrepancies are arbitrated by a third consultant, and solutions are reached by consensus. Translated questionnaires undergo a pilot-testing. Suggestions are incorporated into the final questionnaire. Requests for translations originate from the module developers, physicians or pharmaceutical industry, and most translations are performed by professional translators. The translation procedure is managed and supervised by a Translation Coordinator within the EORTC QL Unit in Brussels.

RESULTS

To date, the EORTC QLQ-C30 has been translated and validated into more than 60 languages, with further translations in progress. Translations include all major Western, and many African and Asian languages. The following translation problems were encountered: lack of expressions for specific symptoms in various languages, the use of old-fashioned language, recent spelling reforms in several European countries and different priorities of social issues between Western and Eastern cultures. The EORTC measurement system is now registered for use in over 9000 clinical trials worldwide.

CONCLUSIONS

The EORTC provides strong infrastructure and quality control to produce robust translated questionnaires. Nevertheless, translation problems have been identified. The key to improvements may lie in the particular features and strengths of the group, consisting of researchers from 21 countries representing 25 languages and include the development of simple source versions, the use of advanced computerised tools, rigorous pilot-testing, certification procedures and insights from a unique cross-cultural database of nearly 40,000 questionnaire responses.