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Terrasson-Lavilledieu, France

Purpose: Missing items are common in quality of life (QoL) questionnaires and present a challenge for research in this field. It remains unclear which of the various methods proposed to deal with missing data performs best in this context. We compared personal mean score, full information maximum likelihood, multiple imputation, and hot deck techniques using various realistic simulation scenarios of item missingness in QoL questionnaires constructed within the framework of classical test theory. Methods: Samples of 300 and 1,000 subjects were randomly drawn from the 2003 INSEE Decennial Health Survey (of 23,018 subjects representative of the French population and having completed the SF-36) and various patterns of missing data were generated according to three different item non-response rates (3, 6, and 9%) and three types of missing data (Little and Rubin's "missing completely at random," "missing at random," and "missing not at random"). The missing data methods were evaluated in terms of accuracy and precision for the analysis of one descriptive and one association parameter for three different scales of the SF-36. Results: For all item non-response rates and types of missing data, multiple imputation and full information maximum likelihood appeared superior to the personal mean score and especially to hot deck in terms of accuracy and precision; however, the use of personal mean score was associated with insignificant bias (relative bias <2%) in all studied situations. Conclusions: Whereas multiple imputation and full information maximum likelihood are confirmed as reference methods, the personal mean score appears nonetheless appropriate for dealing with items missing from completed SF-36 questionnaires in most situations of routine use. These results can reasonably be extended to other questionnaires constructed according to classical test theory. © 2010 Springer Science+Business Media B.V.

Coste J.,Biostatistics and Epidemiology Unit | Quinquis L.,Biostatistics and Epidemiology Unit | D'Almeida S.,Biostatistics and Epidemiology Unit | Audureau E.,University of Paris Descartes
PLoS ONE | Year: 2014

Background: Relationships between smoking and health-related quality of life (HRQoL) in the general population remain unclear. Objectives: To quantify the independent associations between smoking patterns and HRQoL and to identify any threshold or non-linear tendencies in these associations. Methods: A national representative, cross-sectional household survey of the French general non institutionalized population included 7525 men and 8486 women, aged 25-64 year in 2003. Scores on the eight subscales of the Medical Outcomes Study 36-item Short Form were the primary outcomes. Linear regression analyses were used to evaluate the associations between HRQoL and smoking history, quantity of smoking and smoking cessation while controlling for various socio-economic variables, depression, alcohol dependence and pathological conditions. Analyses were conducted in 2013. Results: Independent associations between smoking and HRQoL were found, including small positive associations for occasional or light smoking (up to 5 cigarettes per day), and larger and diffuse negative associations above this threshold. Much weaker associations and higher thresholds for negative HRQoL were found for women than for men. For ex-smokers of both genders, HRQoL was found to be better between 2 and 5 years after quitting. Conclusions: Smoking was independently related to HRQoL, with large differences according to the pattern and quantity of smoking, and to gender. These results may have considerable relevance both for public health action and care of smokers. Copyright: © 2014 Coste et al.

Pasqualini C.,Gustave Roussy Cancer Campus | Dufour C.,Gustave Roussy Cancer Campus | Goma G.,Biostatistics and Epidemiology Unit | Raquin M.-A.,Gustave Roussy Cancer Campus | And 2 more authors.
Bone Marrow Transplantation | Year: 2016

High-risk neuroblastoma is characterised by poor long-term survival, especially for very high-risk (VHR) patients (poor response of metastases after induction therapy). We report the results of an intensified high-dose chemotherapy (HDC) strategy to improve the prognosis of VHR patients. This strategy was based on tandem HDC with thiotepa and busulfan-melphalan (Bu-Mel) followed by autologous stem cell transplantation (ASCT). All data were prospectively recorded in the Gustave Roussy Paediatric ASCT database. From April 2004 to August 2011, 26 patients were eligible for tandem HDC. The median age at diagnosis was 4.4 years (1-15.9). All patients had metastatic disease. MYCN was amplified in 5/26 tumours. Despite the cumulative toxicity of alkylating agents, the toxicity of the intensified HDC strategy was manageable. Thiotepa-related toxicity was mainly digestive, whereas sinusoidal obstruction syndrome was the main toxicity observed after Bu-Mel. The 3-year event-free survival of this cohort was 37.3% (21.3-56.7). This strategy will be compared with combined 131 I-mIBG/Bu-Mel in the upcoming SIOPEN VHR Neuroblastoma Protocol. © 2016 Macmillan Publishers Limited All rights reserved.

Coste J.,Biostatistics and Epidemiology Unit | Coste J.,University of Paris Descartes | Pouchot J.,University of Paris Descartes | Pouchot J.,University Paris Diderot | And 2 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2012

Context: Treatment for short stature in childhood has been recommended with the purpose of improving adult health-related quality of life (HRQoL). However, there are only limited data available concerning the consequences of body height for HRQoL in adulthood. Objective: Our objective was to investigate the relationship between body height and HRQoL. Design, Setting, and Participants: This national representative, cross-sectional household survey of the French general noninstitutionalized population included 8857 men and 9248 women, aged 18-50 yr, in 2003. Main Outcome Measures: Scores on the eight subscales of the Medical Outcomes Study 36-item Short Form (SF-36) were the primary outcomes. Univariate and multivariate linear regression analyses were used to evaluate the effect of height on HRQoL while controlling for age and various socioeconomic variables and pathological conditions. Results: Height was found to be a very weak predictor of HRQoL both for men and women. Only heights lower than 149.2 and 136.0 cm and higher than 203.6 and 188.7cm, in men and women, respectively, were associated with a clinically significant reduction in physical functioning. The effects of body height on other (mental and social) dimensions of HRQoL were negligible or undetectable. Conclusions: Height appears to have minimal consequences for physical functioning and negligible effects on other dimensions of HRQoL. These results contrast with widely popularized stereotypes and common beliefs and should be carefully considered to avoid further stigmatization and unnecessary medical care of individuals who are at the lower end of the growth distribution. Copyright © 2012 by The Endocrine Society.

Antoun S.,Gustave Roussy | Lanoy E.,Biostatistics and Epidemiology Unit | Albiges-Sauvin L.,Gustave Roussy | Escudier B.,Gustave Roussy
Expert Review of Anticancer Therapy | Year: 2014

According to computed tomography image analysis, skeletal muscle (SM) and adipose tissue areas vary widely in patients with the same body mass index or the same body surface area. Body composition variables such as SM mass, SM density and subcutaneous and visceral adipose tissue have shown value as potential independent predictive factors for survival in cancer patients, although data for patients with renal cell carcinoma (RCC) undergoing targeted therapy remain relatively scarce. Confirmation of their prognostic value is required before they can be considered useful adjuncts to conventional predictive models of survival in RCC patients. In addition, variability in SM mass might affect drug toxicity, with patients with a low rather than high SM mass being at a higher risk of toxicity. A dose tailored to the individual patient's SM mass might lower toxicity in RCC patients, enable completion of the treatment plan and thus impact favorably on treatment effectiveness. © 2014 Informa UK Ltd.

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