Validation of the psychometrics properties of a French quality of life questionnaire among a cohort of renal transplant recipients less than one year.

BACKGROUND: Renal transplantation is considered as the treatment of choice for patients with end-stage renal disease. Health-related quality of life (HRQoL) of renal transplant recipients (RTR) is very important to assess, especially during the first year after transplantation. To provide new evidence about the suitability of HRQoL measures in RTR during the first post-transplant year, we explored the internal structure, reliability and external validity of a French specific HRQoL instrument, the Renal Transplant Quality of life Questionnaire Second Version (RTQ V2). METHODS: The data were issued from the French multicenter cohort of renal transplant patients followed during 4 years (EPIGREN). The HRQoL of RTR was assessed five times (at 1, 3, 6, 9 and 12 months after transplantation) with the RTQ V2, a specific instrument consisting of 32 items describing five dimensions. Socio-demographic information, clinical characteristics and HRQoL (i.e., RTQ V2 and SF-36) were collected. For the five times, psychometric properties of the RTQ V2 were compared to those reported from the reference population assessed in the validation study. RESULTS: Three hundred and thirty-four patients were enrolled. The proportions of well-projected items, item-internal consistency, item-discriminant validity, floor and ceiling effects, Cronbach's alpha coefficients and item goodness-of-fit statistics were satisfactory for each dimension at the five times of the study. The suitability indices of construct validity were higher than 90 % for each time (minimum-maximum: 90.8-97.4 %). The external validity was less satisfactory, with a suitability indices ranged from 46.7 % at M1 to 66.7 % at M12. However, the discrepancies with the reference population (mainly for the gender) appeared logical considering the scientific literature on HRQoL of RTR during the first post-transplant year and may not compromise the external validity. CONCLUSION: These results support the validity and reliability of the RTQ V2 for evaluating HRQoL in RTR during the first post-transplant year, and confirm that the RTQ V2 is a useful tool to assess the HRQoL precociously after transplant.

Analysis, evaluation and adaptation of the ReTransQoL: a specific quality of life questionnaire for renal transplant recipients.

BACKGROUND: End stage renal disease (ESRD) profoundly impacts the lives of patients. Kidney transplantation provides the greatest health-related quality of life (HRQOL) improvement. Its measurement has become an important outcome parameter and a very important criterion in the evaluation of any type of medical treatment, especially in the field of renal transplantation.In 2007, a specific self-administered questionnaire for renal transplant recipients was developed in the French language: the ReTransQol (RTQ).After 5 years of use, the properties of the RTQ needed to be re-evaluated in a larger sample.This paper describes the analysis of the ReTransQol and its adaptation to achieve an improved and revised version. METHODS: The study design included three analysis phases for two samples of adult renal transplant recipients which came from two cross-sectional multicenter studies carried out in France in 2007 and 2012. Psychometrics properties like construct validity, acceptability and feasibility, reliability and convergent validity were evaluated and every analysis resulted in a new version of the questionnaire: the RTQ V2. The construct validity of the new RTQ was assessed with a Confirmatory Factor Analysis on a large sample of patients. RESULTS: The study samples included 1,059 patients and 1,591 patients, respectively. After a principal component analysis, item reduction was performed and a total of 13 items were deleted. A final version of the RTQ V2 was created and comprised of 32 items describing 5 domains: Physical Health, Social Functioning, Medical Care, Treatment and Fear of Losing Graft.The explained variance between the first and second RTQ versions improved from 46.3% to 53.1%. All psychometric properties of RTQ V2 were satisfactory: IIC >0.4, IDV (%) of 100% and Cronbach's Alpha >0.7 in every dimension. The confirmatory analysis showed that the overall scalability of the RTQ V2 was satisfactory; all items showed a good fit to the Rasch model within each dimension, and showed INFIT statistics inside the acceptable range. CONCLUSIONS: Psychometric properties allow this new version of the questionnaire to be used to assess different specific dimensions for the renal transplant population, more effectively than previously possible.

Factors associated with health-related quality of life in renal transplant recipients: results of a national survey in France.

BACKGROUND: This study aims to identify factors associated with health related quality of life (HRQOL) through a comprehensive analysis of sociodemographic and clinical variables among a representative sample size of renal transplant recipients (RTR) in France. METHODS: A cross-sectional multicenter study was carried out in 2008. All RTR over 18 years old with a functioning graft for at least one year were included. Data included socio-demographic, health status, and treatment characteristics. To evaluate HRQOL, the Short Form-36 Health Survey (SF-36) and a HRQOL instrument for RTR (ReTransQol) were administered. Multivariate linear regression models were performed. RESULTS: A total of 1061 RTR were included, with a return rate of 72.5%. The variance explained in regression models of SF-36 ranges from 20% to 40% and from 9% to 33% for ReTransQol. CONCLUSIONS: The originality of our study's findings was that novel variables, particularly treatment side effects and unemployment, have a negative effect on quality of life of RTR. The French Biomedicine Agency and the National Health Institute for Public Health Surveillance conduct specific actions for professional reintegration and therapeutic education programs in the national plan to improve the HRQOL of people living with chronic diseases.

[Comparison of two national quality of life surveys for patients with end stage renal disease between 2005-2007 and 2011: indicators slightly decreased]. / Comparaison de deux enquêtes nationales sur la qualité de vie des patients atteints d'insuffisance rénale chronique terminale entre 2005-2007 et 2011: des indicateurs sensiblement en baisse.

BACKGROUND: The Epidemiology Network and Nephrology Information provides since 2001 the epidemiological monitoring of end stage renal disease (ESRD) in France. Two cross-sectional studies to estimate the level of quality of life in ESRD patients were performed in 2005 and 2007 and repeated in 2011. The main objective is to analyze the evolution of the quality of life of ESRD between these two surveys. METHODS: The studies were conducted on a representative sample of subjects aged 18 and over, prevalent dialysis or holders of a functioning kidney transplant last year, followed in center dialysis and/or transplantation in one of the eight French regions selected. The quality of life was measured by a generic questionnaire, and two specifics questionnaires. RESULTS: The evolution of the quality of life deteriorated slightly between 2005-2007 and 2011. There is however few dimensions affected. The variation in scores is not meaningful in general, with maximum decreases less than 4 points according to the statistical methods used. This diminution is not clinically significant. DISCUSSION: The quality of life in dialysis patients or transplant did not evolve between 2005-2007 and 2011. Currently, it is difficult to assess the benefits of the national plan for improving the quality of life of people with chronic diseases because the last data are too close to the end of the plan.