Minimally important differences for interpreting EORTC QLQ-C30 change scores over time: A synthesis across 21 clinical trials involving nine different cancer types.

INTRODUCTION: Early guidelines for minimally important differences (MIDs) for the EORTC QLQ-C30 proposed ≥10 points change as clinically meaningful for all scales. Increasing evidence that MIDs can vary by scale, direction of change, cancer type and estimation method has raised doubt about a single global standard. This paper identifies MID patterns for interpreting group-level change in EORTC QLQ-C30 scores across nine cancer types. METHODS: Data were obtained from 21 published EORTC Phase III trials that enroled 13,015 patients across nine cancer types (brain, colorectal, advanced breast, head/neck, lung, mesothelioma, melanoma, ovarian, and prostate). Anchor-based MIDs for within-group change and between-group differences in change over time were obtained via mean change method and linear regression, respectively. Separate MIDs were estimated for improvements and deteriorations. Distribution-based estimates were derived and compared with anchor-based MIDs. RESULTS: Anchor-based MIDs mostly ranged from 5 to 10 points. Differences in MIDs for improvement vs deterioration, for both within-group and between-group, were mostly within a 2-points range. Larger differences between within-group and between-group MIDs were observed for several scales in ovarian, lung and head/neck cancer. Most anchor-based MIDs ranged between 0.3 SD and 0.5 SD distribution-based estimates. CONCLUSIONS: Our results reinforce recent claims that no single MID can be applied to all EORTC QLQ-C30 scales and disease settings. MIDs varied by scale, improvement/deterioration, within/between comparisons and by cancer type. Researchers applying commonly used rules of thumb must be aware of the risk of dismissing changes that are clinically meaningful or underpowering analyses when smaller MIDs apply.

Minimally important differences of EORTC QLQ-C30 scales in patients with lung cancer or malignant pleural mesothelioma - Interpretation guidance derived from two randomized EORTC trials.

OBJECTIVES: A minimally important difference (MID) is the smallest difference in quality of life (QoL) perceived as relevant by patients or clinicians. MIDs aid interpretation of QOL data in research and clinical practice. We aimed to determine MIDs for the EORTC QLQ-C30 for patients with lung cancer or malignant pleural mesothelioma. MATERIALS AND METHODS: Data were drawn from two EORTC-sponsored randomized clinical trials (RCTs): a three-arm RCT of two cisplatin-based treatments and paclitaxel plus gemcitabine in advanced non-small-cell lung cancer, and an RCT comparing cisplatin with or without raltitrexed in patients with malignant pleural mesothelioma. MIDs for interpreting within-group change and between-group differences in change over time were computed using anchor-based approaches, for improvements and deteriorations separately. Distribution-based approaches provided corroborative evidence. RESULTS: The combined data from the trials comprised 730 patients. Available data allowed us to determine 8/14 anchor-based MIDs for EORTC scales for improvements, and 9/14 MIDs for deterioration. Furthermore, we provided distribution-based estimates for all 14 QLQ-C30 scales. Most MIDs for improvements ranged between 5 and 10, for both within-group and between-group differences. Outliers were appetite loss and constipation, with MIDs up to 15 score points. MIDs were slightly larger for within-group deterioration, ranging from -5 to - 15, with the largest for Nausea/vomiting (-1 to 4) and Appetite loss (-1 to 5). MIDs for between-group differences in deterioration ranged from - 4 (Physical, Role, and Social functioning, and Global quality of life) to -9 (Nausea/vomiting, Appetite loss and Constipation). CONCLUSIONS: MIDs vary over scales and for between- versus within-group comparisons; this must be taken into account when interpreting changes. Nevertheless, the majority of MIDs range between 5 and 10 score points, in line with previously used thresholds for QLQ-C30. These findings and those from other tumor-specific MID analyses will inform a planned consensus process identifying commonalities and differences across tumor sites.

Randomized Trial of a Supportive Psychotherapy for Parents of Adolescents and Young Adults With Hematologic Malignancies.

BACKGROUND: Cancer regularly disrupts health and developmental trajectories in adolescents and young adults (AYAs). Parents have been shown to have a substantial impact on the health and cancer survivorship activities of AYA patients in the form of symptom management. However, no randomized controlled trial has evaluated a coping support intervention (CSI) program for parents of AYAs with cancer aged 18 to 40 years. PATIENTS AND METHODS: From November 30, 2012, to August 29, 2016, parents of AYAs with hematologic malignancies were randomized in a phase III controlled trial (1:1 ratio, stratified sampling) to either the research-based CSI AYA-Parents group (CSI group; n=82) or the standard care (SC) group (n=70). CSI consisted of 5 sessions to achieve the enhancement of parental adaptive coping as the primary outcome (per the adaptive coping scale of the 28-item Brief COPE, a validated multidimensional self-assessment-questionnaire recommended for clinical cancer research). Measures of adaptive coping, depression, and mental health were collected at pre-CSI (measurement date T1), at the end of the intervention sessions (measurement date T2), and at follow-up (3 months). We calculated mean change scores in outcomes and estimated intervention effect sizes (Cohen's d) for changes from T1 to T2/T3, with 0.2 indicating a small effect, 0.5 a medium effect, and 0.8 a large effect. All statistical tests were 2-sided. RESULTS: In the intention-to-treat analysis, the CSI group significantly improved their adaptive coping compared with the SC group (95% CI, 0.30-2.54; P=.013; d=0.405), whereas adaptive coping in the SC group deteriorated. The CSI group also experienced a significant decrease in depressive symptoms and improved mental health with clinical significance (95% CI, -1.98 to -0.30; P=.008; d=0.433, and 95% CI, -0.19 to 3.97; P=.074; d=0.292, respectively). Sensitivity analyses confirmed the robustness of the main intention-to-treat analysis. CONCLUSIONS: CSI improved effectively adaptive coping and depression in parents of AYAs with hematologic malignancies. It may represent a novel family-based approach in AYA oncology care.

Minimally important differences for the EORTC QLQ-C30 in prostate cancer clinical trials.

BACKGROUND: The aim of the study was to estimate the minimally important difference (MID) for interpreting group-level change over time, both within a group and between groups, for the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) scores in patients with prostate cancer. METHODS: We used data from two published EORTC trials. Clinical anchors were selected by strength of correlations with QLQ-C30 scales. In addition, clinicians' input was obtained with regard to plausibility of the selected anchors. The mean change method was applied for interpreting change over time within a group of patients and linear regression models were fitted to estimate MIDs for between-group differences in change over time. Distribution-based estimates were also evaluated. RESULTS: Two clinical anchors were eligible for MID estimation; performance status and the CTCAE diarrhoea domain. MIDs were developed for 7 scales (physical functioning, role functioning, social functioning, pain, fatigue, global quality of life, diarrhoea) and varied by scale and direction (improvement vs deterioration). Within-group MIDs ranged from 4 to 14 points for improvement and - 13 to - 5 points for deterioration and MIDs for between-group differences in change scores ranged from 3 to 13 for improvement and - 10 to - 5 for deterioration. CONCLUSIONS: Our findings aid the meaningful interpretation of changes on a set of EORTC QLQ-C30 scale scores over time, both within and between groups, and for performing more accurate sample size calculations for clinical trials in prostate cancer.

Establishing anchor-based minimally important differences for the EORTC QLQ-C30 in glioma patients.

BACKGROUND: Minimally important differences (MIDs) allow interpretation of the clinical relevance of health-related quality of life (HRQOL) results. This study aimed to estimate MIDs for all European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 (QLQ-C30) scales for interpreting group-level results in brain tumor patients. METHODS: Clinical and HRQOL data from three glioma trials were used. Clinical anchors were selected for each EORTC QLQ-C30 scale, based on correlation (>0.30) and clinical plausibility of association. Changes in both HRQOL and the anchors were calculated, and for each scale and time period, patients were categorized into one of the three clinical change groups: deteriorated by one anchor category, no change, or improved by one anchor category. Mean change method and linear regression were applied to estimate MIDs for interpreting within-group change and between-group differences in change over time, respectively. Distribution-based methods were applied to generate supportive evidence. RESULTS: A total of 1687 patients were enrolled in the three trials. The retained anchors were performance status and eight Common Terminology Criteria for Adverse Events (CTCAE) scales. MIDs for interpreting within-group change ranged from 4 to 12 points for improvement and -4 to -14 points for deterioration. MIDs for between-group difference in change ranged from 4 to 9 for improvement and -4 to -16 for deterioration. Most anchor-based MIDs were closest to the 0.3 SD distribution-based estimates (range: 3-10). CONCLUSIONS: MIDs for the EORTC QLQ-C30 scales generally ranged between 4 and 11 points for both within-group mean change and between-group mean difference in change. These results can be used to interpret QLQ-C30 results from glioma trials.

Reference values for the EORTC QLQ-C30 in patients with advanced stage Hodgkin lymphoma and in Hodgkin lymphoma survivors.

OBJECTIVES: To provide reference values for the European Organisation for Treatment and Research of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30) in advanced-stage Hodgkin lymphoma (HL) patients and 5-year HL survivors. The QLQ-C30 is the most widely used cancer-specific questionnaire to assess Health-Related Quality of Life (HRQoL). METHODS: The EORTC database was searched to identify HL RCTs in which patients' and survivors' HRQoL was assessed by the QLQ-C30. HRQoL mean scores were calculated and stratified by age and gender. Minimal important differences were used to assess the clinical relevance of the findings. Data from one RCT with HRQoL scores available at baseline (n = 343) and four RCTs with HRQoL scores available at follow-up (n = 1665) were analyzed. RESULTS: Patients reported worse HRQoL scores than survivors across most functioning scales and symptoms' scales. These scores varied as a function of gender but not age. Survivors' HRQoL reports were comparable to the ones of the general population. CONCLUSIONS: These values provide an assessment framework for the comparison and interpretation of QLQ-C30 scores in advanced-stage HL. Our findings suggest that although HL patients' HRQoL scores are worse than the general population, HRQoL scores may normalize over long-term survival.

Minimally important differences for interpreting European Organisation for Research and Treatment of Cancer (EORTC) Quality of life Questionnaire core 30 scores in patients with ovarian cancer.

INTRODUCTION: Minimal important differences (MIDs) are useful for interpreting changes or differences in health-related quality of life scores in terms of clinical importance. There are currently no MID guidelines for the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire core 30 (EORTC QLQ-C30) specific to ovarian cancer. This study aims to estimate MIDs for interpreting group-level change of EORTC QLQ-C30 scores in ovarian cancer. METHODS: Data were derived from four EORTC published trials. Clinical anchors for each EORTC QLQ-C30 scale were selected using correlation strength and clinical plausibility. MIDs for within-group change and between-group differences in change over time were estimated via mean change method and linear regression respectively. For each EORTC QLQ-C30 scale, MID estimates from multiple anchors were summarized via weighted-correlation. Distribution-based MIDs were also examined as supportive evidence. RESULTS: Anchor-based MIDs were determined for deterioration in 7 of the 14 EORTC QLQ-C30 scales assessed, and in 11 scales for improvement. Anchor-based MIDs for within-group change ranged from 4 to 19 (improvement) and - 9 to -4 (deterioration). Between-group MIDs ranged from 3 to 13 (improvement) and - 11 to -4 (deterioration). Generally, absolute anchor-based MIDs for most scales ranged from 4 to 10 points. CONCLUSIONS: Our findings will aid interpretation of EORTC QLQ-C30 scores in ovarian cancer and inform sample size calculations in future ovarian cancer trials with endpoints that are based on EORTC QLQ-C30 scales.

Hodgkin lymphoma.

Hodgkin lymphoma (HL) is a B cell lymphoma characterized by few malignant cells and numerous immune effector cells in the tumour microenvironment. The incidence of HL is highest in adolescents and young adults, although HL can affect elderly individuals. Diagnosis is based on histological and immunohistochemical analyses of tissue from a lymph node biopsy; the tissue morphology and antigen expression profile enable classification into one of the four types of classic HL (nodular sclerosis, mixed cellularity, lymphocyte-depleted or lymphocyte-rich HL), which account for the majority of cases, or nodular lymphocyte-predominant HL. Although uncommon, HL remains a crucial test case for progress in cancer treatment. HL was among the first systemic neoplasms shown to be curable with radiation therapy and multiagent chemotherapy. The goal of multimodality therapy is to minimize lifelong residual treatment-associated toxicity while maintaining high levels of effectiveness. Recurrent or refractory disease can be effectively treated or cured with high-dose chemotherapy followed by autologous haematopoietic stem cell transplantation, and prospective trials have demonstrated the potency of immunotherapeutic approaches with antibody-drug conjugates and immune checkpoint inhibitors. This Primer explores the wealth of information that has been assembled to understand HL; these updated observations verify that HL investigation and treatment remain at the leading edge of oncological research.

Health-Related Quality of Life in Patients With Hodgkin Lymphoma: A Longitudinal Analysis of the German Hodgkin Study Group.

PURPOSE: Many important details of health-related quality of life (HRQoL) after diagnosis and treatment of Hodgkin lymphoma (HL) are still unknown because large longitudinal studies of HRQoL are rare. Therefore, we analyzed a systematically assessed, comprehensive range of HRQoL domains in patients with HL of all stages from diagnosis up to 5 years of survivorship. PATIENTS AND METHODS: We included patients with HL age 18-60 years at diagnosis from the German Hodgkin Study Group trials HD13, HD14, and HD15. We analyzed HRQoL using all functional and symptom scales of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 including deviations from reference values. We estimated the effect of different disease, patient, and treatment characteristics using multiple regression and repeated measures analysis and computed correlations of HRQoL scores. RESULTS: We analyzed 4,215 patients with any HRQoL assessment within 5 years after treatment. Higher tumor burden at diagnosis was associated with impaired baseline scores in many HRQoL domains. During survivorship, cognitive, emotional, role, and social functioning and fatigue, dyspnea, sleep, and financial problems were severely and persistently affected. From year 2 on, mean deviations from reference values ranged between 12 and 29 points, with 10 points being a commonly used margin of clinical relevance. In all 3 trials, HRQoL domains 2 and 5 years after therapy were significantly influenced by baseline scores and age but not by randomized treatments. Fatigue was most closely correlated with other symptoms and scales. CONCLUSION: Our results show a high and persistent amount of different HRQoL deficits in survivors of HL that are largely independent of the applied chemotherapies. Our analysis underscores the high, unmet medical need of these rather young survivors of HL regarding the psychosocial adverse effects of the cancer experience.

International standards for the analysis of quality-of-life and patient-reported outcome endpoints in cancer randomised controlled trials: recommendations of the SISAQOL Consortium.

Patient-reported outcomes (PROs), such as symptoms, function, and other health-related quality-of-life aspects, are increasingly evaluated in cancer randomised controlled trials (RCTs) to provide information about treatment risks, benefits, and tolerability. However, expert opinion and critical review of the literature showed no consensus on optimal methods of PRO analysis in cancer RCTs, hindering interpretation of results. The Setting International Standards in Analyzing Patient-Reported Outcomes and Quality of Life Endpoints Data Consortium was formed to establish PRO analysis recommendations. Four issues were prioritised: developing a taxonomy of research objectives that can be matched with appropriate statistical methods, identifying appropriate statistical methods for PRO analysis, standardising statistical terminology related to missing data, and determining appropriate ways to manage missing data. This Policy Review presents recommendations for PRO analysis developed through critical literature reviews and a structured collaborative process with diverse international stakeholders, which provides a foundation for endorsement; ongoing developments of these recommendations are also discussed.

Sensitivity to change of the EORTC quality of life module measuring cancer-related fatigue (EORTC QlQ-Fa12): Results from the international psychometric validation.

OBJECTIVE: The European Organisation for Research and Treatment of Cancer Quality of Life Group (EORTC QLG) has developed a multidimensional instrument measuring cancer-related fatigue, the EORTC QLQ-FA12. The analysis of sensitivity to change is an essential part of psychometric validation. With this study, we investigated the EORTC QLQ-FA12's sensitivity to change. METHODS: The methodology follows the EORTC guidelines of EORTC QLG for phase IV validation of modules. We included cancer patients undergoing curative and palliative treatment at t1 and followed them up prospectively over the course of their treatment (t2) and 4 weeks after completion of treatment (t3). Data were collected prospectively at 17 sites in 11 countries. Sensitivity to change was investigated using analysis of variance. RESULTS: A total sample of 533 patients was enrolled with various tumour types, different stages of cancer, and receiving either curative treatment (n=311) or palliative treatment (n=222). Over time all fatigue scores were significantly higher in the palliative treatment group compared with the curative group (p < .001). Physical fatigue increased with medium effect size over the course of treatment in the curative group (standardized response mean [SRM] (t1,t2) = 0.44]. After treatment physical [SRM (t2,t3) = 0.39], emotional [SRM (t2,t3)= 0.28] and cognitive fatigue (SRM [t2,t3] = 0.22) declined significantly in the curative group. In the palliative group, emotional (SRM [t2,t3] = 0.18) as well as cognitive [SRM [t2,t3] = 0.26) fatigue increases significantly. CONCLUSIONS: The EORTC-QLQ-FA12 proved to identify clinically significant changes in fatigue in the course of curative and palliative cancer treatment.

Minimally Important Differences for Interpreting EORTC QLQ-C30 Scores in Patients With Advanced Breast Cancer.

BACKGROUND: We aimed to estimate the minimally important difference (MID) for interpreting group-level change over time, both within a group and between groups, for the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire core 30 (EORTC QLQ-C30) scores in patients with advanced breast cancer. METHODS: Data were derived from two published EORTC trials. Clinical anchors (eg, performance status [PS]) were selected using correlation strength and clinical plausibility of their association with a particular QLQ-C30 scale. Three change status groups were formed: deteriorated by one anchor category, improved by one anchor category, and no change. Patients with greater anchor changes were excluded. The mean change method was used to estimate MIDs for within-group change, and linear regression was used to estimate MIDs for between-group differences in change over time. For a given QLQ-C30 scale, MID estimates from multiple anchors were triangulated to a single value via a correlation-based weighted average. RESULTS: MIDs varied by QLQ-C30 scale, direction (improvement vs deterioration), and anchor. MIDs for within-group change ranged from 5 to 14 points (improvement) and -14 to -4 points (deterioration), and MIDs for between-group change over time ranged from 4 to 11 points and from -18 to -4 points. Correlation-weighted MIDs for most QLQ-C30 scales ranged from 4 to 10 points in absolute values. CONCLUSIONS: Our findings aid interpretation of changes in EORTC QLQ-C30 scores over time, both within and between groups, and for performing more accurate sample size calculations for clinical trials in advanced breast cancer.

Interpreting European Organisation for Research and Treatment for Cancer Quality of life Questionnaire core 30 scores as minimally importantly different for patients with malignant melanoma.

INTRODUCTION: Health-related quality of life (HRQOL) is increasingly recognised as an important end-point in cancer clinical trials. The concept of minimally important difference (MID) enables interpreting differences and changes in HRQOL scores in terms of clinical meaningfulness. We aimed to estimate MIDs for interpreting group-level change of European Organisation for Research and Treatment for Cancer Quality of life Questionnaire core 30 (EORTC QLQ-C30) scores in patients with malignant melanoma. METHODS: Data were pooled from three published melanoma phase III trials. Anchors relying on clinician's ratings, e.g. performance status, were selected using correlation strength and clinical plausibility of associating the anchor/EORTC QLQ-C30 scale pair. HRQOL change was evaluated between time periods that were common to all trials: start of treatment to end of treatment and end of treatment to end of follow-up. Three change status groups were formed: deteriorated by one anchor category, improved by one anchor category and no change. Patients with greater anchor change were excluded. The mean change method and linear regression were used to estimate MIDs for change in HRQOL scores within the group and between the groups of patients, respectively. RESULTS: MIDs varied according to QLQ-C30 scale, direction (improvement versus deterioration), anchor and period. MIDs for within-group change ranged from 4 to 18 points (improvement) and -16 to -4 points (deterioration), and MIDs for between-group change ranged from 3 to 16 points and from -16 to -3 points. MIDs for most of QLQ-C30 scales ranged from 5 to 10 points in absolute values. CONCLUSIONS: These results are useful for interpreting changes in EORTC QLQ-C30 scores over time and for performing more accurate sample size calculations in adjuvant melanoma settings.

Statistical analysis of patient-reported outcome data in randomised controlled trials of locally advanced and metastatic breast cancer: a systematic review.

Although patient-reported outcomes (PROs), such as health-related quality of life, are important endpoints in randomised controlled trials (RCTs), there is little consensus about the analysis, interpretation, and reporting of these data. We did a systematic review to assess the variability, quality, and standards of PRO data analyses in advanced breast cancer RCTs. We searched PubMed for English language articles published in peer-reviewed journals between Jan 1, 2001, and Oct 30, 2017. Eligible articles were those that reported PRO results from RCTs of adult patients with advanced breast cancer receiving anti-cancer treatments with reported sample sizes of at least 50 patients-66 RCTs met the selection criteria. Only eight (12%) RCTs reported a specific PRO research hypothesis. Heterogeneity in the statistical methods used to assess PRO data was observed, with a mixture of longitudinal and cross-sectional techniques. Not all articles addressed the problem of multiple testing. Fewer than half of RCTs (28 [42%]) reported the clinical significance of their findings. 48 (73%) did not report how missing data were handled. Our systematic review shows a need to improve standards in the analysis, interpretation, and reporting of PRO data in cancer RCTs. Lack of standardisation makes it difficult to draw robust conclusions and compare findings across trials. The Setting International Standards in the Analyzing Patient-Reported Outcomes and Quality of Life Data Consortium was set up to address this need and develop recommendations on the analysis of PRO data in RCTs.

Moving forward toward standardizing analysis of quality of life data in randomized cancer clinical trials.

BACKGROUND: There is currently a lack of consensus on how health-related quality of life and other patient-reported outcome measures in cancer randomized clinical trials are analyzed and interpreted. This makes it difficult to compare results across randomized controlled trials (RCTs) synthesize scientific research, and use that evidence to inform product labeling, clinical guidelines, and health policy. The Setting International Standards in Analyzing Patient-Reported Outcomes and Quality of Life Endpoints Data for Cancer Clinical Trials (SISAQOL) Consortium aims to develop guidelines and recommendations to standardize analyses of patient-reported outcome data in cancer RCTs. METHODS AND RESULTS: Members from the SISAQOL Consortium met in January 2017 to discuss relevant issues. Data from systematic reviews of the current state of published research in patient-reported outcomes in cancer RCTs indicated a lack of clear reporting of research hypothesis and analytic strategies, and inconsistency in definitions of terms, including "missing data,""health-related quality of life," and "patient-reported outcome." Based on the meeting proceedings, the Consortium will focus on three key priorities in the coming year: developing a taxonomy of research objectives, identifying appropriate statistical methods to analyze patient-reported outcome data, and determining best practices to evaluate and deal with missing data. CONCLUSION: The quality of the Consortium guidelines and recommendations are informed and enhanced by the broad Consortium membership which includes regulators, patients, clinicians, and academics.

Quality of life as a prognostic indicator of survival: A pooled analysis of individual patient data from canadian cancer trials group clinical trials.

BACKGROUND: The aims of this study were to externally validate an established association between baseline health-related quality of life (HRQOL) scores and survival and to assess the added prognostic value of HRQOL with respect to demographic and clinical indicators. METHODS: Pooled data were analyzed from 17 randomized controlled trials opened by the Canadian Cancer Trials Group between 1991 and 2004; they included survival and baseline HRQOL data from 3606 patients with 8 different cancer sites. The models included sex, age (≤60 vs >60 years), World Health Organization performance status (0 or 1 vs 2-4), distant metastases (no vs yes), and 15 European Organization for Research and Treatment of Cancer (EORTC) Core Quality-of-Life Questionnaire (QLQ-C30) scales. Analyses were conducted with multivariate Cox proportional hazards models and were stratified by cancer site. Harrell's discrimination C-index was used to calculate the predictive accuracy of the model when HRQOL parameters were added to clinical and demographic variables. The added value of adding HRQOL scales to clinical and demographic variables was illustrated with Kaplan-Meier curves. RESULTS: In the stratified, multivariate model, HRQOL parameters-global health status (hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.95-1.00; P < . 0001), dyspnea (HR, 1.04; 95% CI, 1.02-1.06; P < . 0002), and appetite loss (HR, 1.06; 95% CI, 1.04-1.08; P < . 0001)-were independent prognostic factors in addition to the demographic and clinical variables (all P values < .05). Adding these HRQOL variables to the clinical variables resulted in an added relative prognostic value for survival of 5%. CONCLUSIONS: These results confirm previous findings showing that baseline HRQOL scores on the EORTC QLQ-C30 provide prognostic information in addition to information from clinical measures. However, the impact of specific domains may differ across studies. Cancer 2018. © 2018 American Cancer Society.

Establishing anchor-based minimally important differences (MID) with the EORTC quality-of-life measures: a meta-analysis protocol.

INTRODUCTION: As patient assessment of health-related quality of life (HRQOL) in cancer clinical trials has increased over the years, so has the need to attach meaningful interpretations to differences in HRQOL scores between groups and changes within groups. Determining what represents a minimally important difference (MID) in HRQOL scores is useful to clinicians, patients and researchers, and can be used as a benchmark for assessing the success of a healthcare intervention. Our objective is to provide an evidence-based protocol to determine MIDs for the European Organisation for Research and Treatment for Cancer Quality of life Questionnaire core 30 (EORTC QLQ-C30). We will mainly focus on MID estimation for group-level comparisons. Responder thresholds for individual-level change will also be estimated. METHODS AND ANALYSIS: Data will be derived from published phase II and III EORTC trials that used the QLQ-C30 instrument, covering several cancer sites. We will use individual patient data to estimate MIDs for different cancer sites separately. Focus is on anchor-based methods. Anchors will be selected per disease site from available data. A disease-oriented and methodological panel will provide independent guidance on anchor selection. We aim to construct multiple clinical anchors per QLQ-C30 scale and also to compare with several anchor-based methods. The effects of covariates, for example, gender, age, disease stage and so on, will also be investigated. We will examine how our estimated MIDs compare with previously published guidelines, hence further contributing to robust MID guidelines for the EORTC QLQ-C30. ETHICS AND DISSEMINATION: All patient data originate from completed clinical trials with mandatory written informed consent, approved by local ethical committees. Our findings will be presented at scientific conferences, disseminated via peer-reviewed publications and also compiled in a MID 'blue book' which will be made available online on the EORTC Quality of Life Group website as a free guideline document.

International Psychometric Validation of an EORTC Quality of Life Module Measuring Cancer Related Fatigue (EORTC QLQ-FA12).

Background: The European Organisation for Research and Treatment of Cancer (EORTC) Group has developed a new multidimensional instrument measuring cancer-related fatigue to be used in conjunction with the quality of life core questionnaire (EORTC QLQ-C30). The module EORTC QLQ-FA13 assesses physical, cognitive, and emotional aspects of cancer-related fatigue. Methods: The methodology follows the EORTC guidelines for phase IV validation of modules. This paper focuses on the results of the psychometric validation of the factorial structure of the module. For validation and cross-validation confirmatory factor analysis (maximum likelihood estimation), intraclass correlation and Cronbach alpha for internal consistency were employed. The study involved an international multicenter collaboration of 11 European and non-European countries. Results: A total of 946 patients with various tumor diagnoses were enrolled. Based on the confirmatory factor analysis, we could approve the three-dimensional structure of the module. Removing one item and reassigning the factorial mapping of another item resulted in the EORTC QLQ-FA12. For the revised scale, we found evidence supporting good local (indicator reliability ≥ 0.60, factor reliability ≥ 0.82) and global model fit (GFI t1|t2 = 0.965/0.957, CFI t1|t2 = 0.976/0.972, RMSEA t1|t2 = 0.060/0.069) for both measurement points. For each scale, test-retest reliability proved to be very good (intraclass correlation: R t1-t2 = 0.905-0.921) and internal consistency proved to be good to high (Cronbach alpha = .79-.90). Conclusion: Based on the former phase III module, the multidimensional structure was revised as a phase IV module (EORTC FA12) with an improved scale structure. For a comprehensive validation of the EORTC FA12, further aspects of convergent and divergent validity as well as sensitivity to change should be determined.