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ABSTRACT: OBJECTIVE: To review current practice and update guidelines for the methodology of shortening composite measurement scales (CMSs). STUDY DESIGN AND SETTING: A literature review gathered data on 91 shortening processes from 1995 to 2009. The validity of the initial CMS, the shortening methods, and the validity of the derived short-form scales were examined. The results were compared with those from a previous literature review (articles from 1985 to 1995) to develop updated guidelines for CMS shortening. RESULTS: The literature review revealed a persisting lack of use of rigorous methodology for CMS shortening. Of the 91 cases of CMS shortening, 36 combined a content approach and a statistical approach; 45 used only a statistical approach and 10 (11%) only a content approach. The updated guidelines deal with the validity and conceptual model of the initial CMS, the preservation of content and psychometric properties during shortening, the selection of items, and the validation of the short form. CONCLUSION: Item reduction based on a rigorous methodology is necessary if the short-form instrument aims to maintain the validity and other measurement properties of the parent instrument, which in turn supports application in research and clinical practice.
Journal of clinical epidemiology 04/2013; · 2.96 Impact Factor
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ABSTRACT: BACKGROUND: The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in cystic fibrosis (CF) patients has increased and MRSA seems to be associated with a poorer prognosis. The aim of this study was to assess the prevalence and clinical consequences of MRSA and methicillin-susceptible Staphylococcus aureus (MSSA), associated or not associated with Pseudomonas aeruginosa (PA). METHODS: In a retrospective study on 419 sputum producer patients (293 adults and 126 children >7years of age), we recorded patient characteristics, lung function, nutritional status, IV antibiotics and hospitalisations, the presence of SA and/or PA and FEV1 decline over 2years. RESULTS: SA was found in 72% of the patients: MSSA in 68.2% of children and 48.8% of adults; MRSA in 17.5% of children and 17.8% of adults. Sixty percent of MRSA patients and 60.4% of MSSA patients also harboured PA. The rate of deterioration of clinical status of the various groups, as assessed from respiratory function, IV antibiotic courses and hospitalisations, increased in the order: no SA/no PA, MSSA alone, MRSA alone, MSSA/PA, MRSA/PA, and PA alone. Nutritional status did not differ between groups. Results were roughly similar for children and adults. The yearly FEV1 decline was significantly higher only for MRSA/PA patients (p=0.03) compared to no SA/no PA patients. CONCLUSION: Clinical condition of CF patients with MSSA only or MRSA only appeared similar, whereas MRSA/PA patients had more severe respiratory function than MSSA/PA patients. In CF patients, MRSA might be more deleterious than MSSA only when associated with PA.
Journal of cystic fibrosis: official journal of the European Cystic Fibrosis Society 01/2013; · 3.19 Impact Factor
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ABSTRACT: BACKGROUND: This study aims at analyzing Health related quality of life (HRQoL) data on the French general population between 1995 and 2003 using an Item Response Theory (IRT) model. METHODS: Data concerned 26388 individuals having responded to the SF36 questionnaire in 1995 or in 2003. General Health, Mental Health and Physical Functioning dimensions have been analyzed using a latent regression mixed Partial Credit Model. Differential Item Functioning (DIF) have been searched on each item between age categories, genders, regions of residency, and years of study. Mean and variance of the latent traits have been explained by the same variables, in order to quantify their impact. RESULTS: Few DIF have been detected between age categories or genders. The analysis shows already known evolutions for HRQoL data: the decrease with age and the differences between genders with worst values for women. We note differences between regions, with better mean value in Paris, in the West or in the South of France, and worst values in the North and in the East. Last, a decrease of the three studied dimensions is noted between 1995 and 2003. CONCLUSIONS: This study using IRT model offers several advantages compared to a classical approach based on scores. First, DIF can be taken into account. More, handling of missing data is easy, because IRT models do not required imputation of missing data. Last, analysis using IRT model is more powerful than analysis based on scores, and allow highlighting a most important number of effects.
BMC Medical Research Methodology 11/2012; 12(1):182. · 2.67 Impact Factor
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ABSTRACT: OBJECTIVES: To assess the reliability and diagnostic accuracy of qualitative evaluation of apparent diffusion coefficient (ADC) mapping with magnetic resonance imaging (MRI) in differentiating between complete and partial anterior cruciate ligament (ACL) tears. METHODS: This prospective study protocol was approved by the institutional ethics review board and informed consent was obtained from all the patients. Eighty-five patients (35 women and 50 men, mean age 34.1 years) with recent (<4 months) knee trauma with suspected ACL injury underwent conventional MRI (T1-weighted and T2-weighted sequences with fat saturation) associated with ADC mapping. MR images were read qualitatively without and then with ADC mapping by three radiologists, with analysis of direct signs of a traumatic ACL tear and a second-reading. Dynamic X-rays (43 patients) or arthroscopies (42 patients) were used as reference standards. RESULTS: For complete ACL tear diagnosis (67 patients), sensitivity and specificity were 87% and 50% respectively with conventional MRI, and 96% and 94% respectively with ADC mapping (P < 0.01 for specificity). Inter-observer correlations between musculoskeletal radiologists were almost perfect (κ = 0.81) with ADC mapping and fair with conventional MRI on the second-reading. CONCLUSIONS: ADC mapping associated with conventional MR sequences is a reproducible method to better differentiate complete and partial ACL tears. KEY POINTS : • MRI is widely used for assessing the problematic knee • Additional diffusion-weighted sequences help differentiate between complete and partial ACL tears • DW-MRI for ACL requires a reader-dependent learning curve • Reliable visualisation of complete ACL tears allows more appropriate management of patients.
European Radiology 08/2012; · 3.22 Impact Factor
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ABSTRACT: 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.
The Journal of clinical endocrinology and metabolism 06/2012; 97(9):3231-9. · 6.50 Impact Factor
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ABSTRACT: The parental origin of the intact X-chromosome has been reported to affect phenotype and response to GH treatment in Turner syndrome (TS).
Our objective was to evaluate the influence of the parental origin of the X-chromosome on body growth and GH treatment effect in TS.
We conducted a population-based cohort study of TS patients previously treated with GH.
Participants included patients with a nonmosaic 45,X karyotype; 556 women were identified as eligible, 233 (49%) of whom participated, together with their mothers. Data were analyzed for 180 of these patients.
We performed fluorescence in situ hybridization analysis to exclude mosaicism and microsatellite analysis of nine polymorphic markers in DNA from the patients and their mothers. The influence on growth and effect of GH were analyzed by univariate and multivariate methods.
The X-chromosome was of paternal origin (X(pat)) in 52 (29%) of 180 and of maternal origin (X(mat)) in 128 (71%) of 180 patients. Height gain from the start of GH treatment to adult height was similar in X(mat) and X(pat) patients (+2.1 ± 0.9 vs. +2.2 ± 0.8 TS sd score, P = 0.45). The lack of influence of parental origin of the X-chromosome was confirmed in multivariate analysis. Parental origin of the X-chromosome also had no effect on the other growth characteristics studied, including growth velocity during the first year on GH treatment. Patient height was correlated with the heights of both parents and was not influenced by the parental origin of the X-chromosome.
In this, the largest such study carried out to date, the parental origin of the X-chromosome did not alter the effect of GH treatment or affect any other features of growth in TS.
The Journal of clinical endocrinology and metabolism 05/2012; 97(7):E1241-8. · 6.50 Impact Factor
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ABSTRACT: Objective To assess the inter- and intra-observer variability in detection and progression assessment with MRI of pituitary microadenomas
in cases of Cushing’s disease treated by adrenalectomy. Design and Methods Two radiologists independently reviewed initial and follow-up MRI studies of 32 patients with a history of Cushing’s disease
on two occasions each. Five classical qualitative signs and three quantitative measurements of microadenoma were considered.
Intra and inter-observer reproducibility was evaluated with kappa statistics (qualitative signs) and intraclass correlation
coefficients and Bland-Altman plots (quantitative measurements). Results No sign or measurement could be identified as better than others and none displayed consistently high levels of inter- or
even intra-observer reproducibility (kappa or intraclass correlation coefficient>0.80). Both qualitative and quantitative
criteria showed lower reproducibility when used for diagnosing progression than when used for diagnosing the presence of an
adenoma. Reproducibility of qualitative signs appeared to be influenced by reader’s experience. Conclusions Pituitary MRI study of patients with Cushing disease treated by adrenalectomy remains difficult. In practice, interpretation
of MRI studies by a well-experienced reader should be preferred, unless a final decision can be reached by consensus between
two and several readers.
Pituitary 04/2012; 11(3):263-269. · 1.83 Impact Factor
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Ronan Bouttier,
Johanne Morvan,
Bernard Mazieres,
Anne-Christine Rat,
Liana Euller Ziegler,
Patrice Fardellone,
Bruno Fautrel,
Francis Guillemin,
Jacques Pouchot,
Christian Roux, Joël Coste,
Alain Saraux
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ABSTRACT: INTRODUCTION: Hip dysplasia may cause pain and premature hip osteoarthritis. Here, our objective was to assess the inter- and intraobserver reproducibility of radiographic hip parameter measurement in adults. METHODS: We used anteroposterior pelvic radiographs and false-profile lateral hip radiographs from 30 individuals (60 hips) enrolled in a prevalence study of hip osteoarthritis. For each hip, two independent observers recorded five parameters twice, at an interval of 1month. The five parameters were the vertical-center-edge angle (VCE), the anterior center-edge angle (vertical-center-anterior angle, VCA), the acetabular roof angle (HTE), the neck-shaft angle (CC'D), and acetabulum depth (AD). Reproducibility was assessed using Bland-Altman plots, intraclass correlation coefficients (ICCs), and kappa coefficients for the radiographic diagnosis of hip dysplasia using widely accepted cutoffs. RESULTS: Of the 60 hips, 51 were assessable. Intraobserver ICC values ranged from 0.72 to 0.94 and interobserver ICC values from 0.68 to 0.84. Kappa coefficients were between 0.60 and 1.00, except for the VCA angle (κ=0.41). CONCLUSION: In this study, reproducibility of the main radiographic hip parameters was good according to all evaluation methods used. However, CC'D and, to an even greater extent, the VCA angle seemed challenging to measure.
Joint, bone, spine: revue du rhumatisme 03/2012; · 2.25 Impact Factor
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ABSTRACT: Little is known about the long-term health of subjects treated with GH in childhood, and Safety and Appropriateness of Growth hormone treatments in Europe (SAGhE) is a study addressing this question.
The objective of the study was to evaluate the long-term mortality of patients treated with recombinant GH in childhood in France.
This was a population-based cohort study.
The setting of the study was a French population-based register.
A total of 6928 children with idiopathic isolated GH deficiency (n = 5162), neurosecretory dysfunction (n = 534), idiopathic short stature (n = 871), or born short for gestational age (n = 335) who started treatment between 1985 and 1996 participated in the study. Follow-up data on vital status were available in September 2009 for 94.7% of the patients.
All-cause and cause-specific mortality was measured in the study.
All-cause mortality was increased in treated subjects [standardized mortality ratio (SMR) 1.33, 95% confidence interval (CI) 1.08-1.64]. In a multivariate analysis adjusted for height, the use of GH doses greater than 50 μg/kg · d was associated with mortality rates using external and internal references (SMR 2.94, 95% CI 1.22-7.07, hazard ratio 2.79, 95% CI 1.14-6.82). All type cancer-related mortality was not increased. Bone tumor-related mortality was increased (SMR 5.00, 95% CI 1.01-14.63). An increase in mortality due to diseases of the circulatory system (SMR 3.07, 95% CI 1.40-5.83) or subarachnoid or intracerebral hemorrhage (SMR 6.66, 95% CI 1.79-17.05) was observed.
Mortality rates were increased in this population of adults treated as children with recombinant GH, particularly in those who had received the highest doses. Specific effects were detected in terms of death due to bone tumors or cerebral hemorrhage but not for all cancers. These results highlight the need for additional studies of long-term mortality and morbidity after GH treatment in childhood.
The Journal of clinical endocrinology and metabolism 02/2012; 97(2):416-25. · 6.50 Impact Factor
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ABSTRACT: The purpose of this study is to describe an imaging method based on a CT technique, CT antegrade colonography, for the evaluation of low anastomosis and to evaluate the value of CT antegrade colonography before early ileostomy closure after proctectomy in low rectal endometriosis.
One hundred ninety-five patients referred for low rectal endometriosis underwent proctectomy and were eligible for early ileostomy closure. All patients underwent standard antegrade fluoroscopy (n=77) or CT antegrade colonography (n=118) 8 days after surgery. The negative predictive values, positive predictive values, sensitivity, specificity, and likelihood ratio of standard antegrade fluoroscopy and CT antegrade colonography in detecting anastomotic leakage and abscesses were assessed. The reference standard for positive and negative examinations was based on clinical follow-up, imaging, surgical, or interventional procedure findings.
Negative and positive predictive values for detecting anastomotic leakage were 100% (95% CI, 96.8-100%) and 100% (95% CI, 39.8-100%), respectively, for CT antegrade colonography and 98.6% (95% CI, 92.4-100%) and 100% (95% CI, 54.1-100%), respectively, for standard antegrade fluoroscopy. The negative and positive predictive values for detecting abscess were 100% (95% CI, 96.8-100%) and 100% (95% CI, 47.8-100%), respectively, for CT antegrade colonography and 97.3% (95% CI, 90.8-99.7%) and 100% (95% CI, 2.5-100%), respectively, for standard antegrade fluoroscopy.
CT antegrade colonography may play a major role in the evaluation of low anastomosis protected by an ileostomy after proctectomy in low rectal endometriosis, leading to the development of a new strategy with early restoration of the intestinal continuity.
American Journal of Roentgenology 01/2012; 198(1):98-105. · 2.78 Impact Factor
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ABSTRACT: Increased life expectancy in patients with cystic fibrosis (CF) allows better knowledge of non-pulmonary complications like liver disease (CFLD). However, few data have been published in large adult cohorts. The aim of this study was to estimate the prevalence and the prognosis of CFLD in adult CF patients.
A retrospective analysis of a monocentric cohort of adult CF patients prospectively followed, at least every year, was performed. CFLD was diagnosed using published composite criteria. If cirrhosis was suspected, upper digestive endoscopy was realized to assess the presence of portal hypertension.
A cohort of 285 adult CF patients was followed during 4.8 ± 3.6 years. Among them, 90 had CFLD at the beginning of follow-up and 23 a suspicion of cirrhosis. Factors independently associated with liver disease at baseline were history of meconium ileus, pancreatic insufficiency, chronic colonization with Burkholderia cepacia and the number of IV antibiotic courses per year. Nine patients developed liver decompensation during follow-up, all with a suspicion of cirrhosis at baseline. Six patients underwent liver transplantation alone and three patients combined liver and lung transplantation. Factors independently associated with death or lung transplantation at baseline were liver disease, BMI, forced expiratory volume in 1 second and number of IV antibiotic courses per year.
CFLD was present at baseline in one third of adult patients with CF with a marked risk of liver decompensation during follow-up. Moreover, CFLD at baseline appears as an independent factor associated with death or lung transplantation.
Journal of Hepatology 05/2011; 55(6):1377-82. · 9.26 Impact Factor
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ABSTRACT: Pituitary surgery is the first line of treatment for Cushing's disease; when surgery fails, bilateral adrenalectomy may be proposed, particularly for women with a desire for pregnancy. Little is known about the impact of pregnancy on corticotroph tumor progression after bilateral adrenalectomy.
The aim was to evaluate the impact of pregnancy on corticotroph tumor progression after bilateral adrenalectomy in Cushing's disease and to assess maternal and pregnancy outcomes.
We conducted a retrospective cohort study.
Patients who became pregnant after bilateral adrenalectomy were followed in a single center.
Twenty pregnancies from 11 patients with Cushing's disease were treated by bilateral adrenalectomy and no pituitary irradiation.
Corticotroph tumor progression was assessed by serial pituitary magnetic resonance imaging and plasma ACTH measurements before, during, and after pregnancy. Comparisons were performed using paired Wilcoxon rank tests. Data on maternal and neonatal outcomes were recorded by correspondence from patients and obstetricians.
Corticotroph tumor progression occurred in eight of 17 pregnancies, and ACTH increased in eight of 10 pregnancies. However, rates of increase during or after pregnancy were not faster than those observed before pregnancy. Maternal complications occurred in four pregnancies from two patients, including gestational hypertension in three and gestational diabetes mellitus in three. Among these four pregnancies, three had a favorable outcome, and one led to an in utero death after eclampsia, due to loss to follow-up. No other maternal or fetal complications were reported.
Pregnancy does not accelerate corticotroph tumor progression after bilateral adrenalectomy. Pregnancy is manageable, provided the patients can be followed closely.
The Journal of clinical endocrinology and metabolism 02/2011; 96(4):E658-62. · 6.50 Impact Factor
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ABSTRACT: Use of TA-US for diagnostic investigation of giant cell arteritis (GCA) has been proposed but remains a matter of debate because of the heterogeneous findings. We retrospectively evaluated operating characteristics of temporal artery ultrasonography (TA-US) in a single teaching hospital.
All subjects with suspected GCA had been seen between 2002 and 2008 and had undergone TA-US with continuous-wave Doppler (until 2004) or color duplex ultrasonography (after 2004), followed within 30 days by a temporal artery biopsy (TAB). TA-US findings were compared with TAB-proven GCA and clinically diagnosed GCA. Results are expressed as sensitivities, specificities, and positive (LR+) and negative likelihood ratios (LR-) of stenoses, occlusions, and the halo sign; for the latter, only color duplex TA-US was considered.
Seventy-seven patients fulfilled the selection criteria; 13 had TAB-proven and 19 had clinically defined GCA. Stenoses/occlusions were seen on 45.5% of TA-US and the halo sign was seen only once (3.2%) in 31 duplex TA-US. Respective sensitivities, specificities, LR+, and LR- for GCA diagnosis (using TAB-proven/clinically defined GCA as reference standards) were 69%/53%, 59%/57%, 1.7/1.2, and 0.5/0.8 for stenoses and/or occlusions, and 17%/10%, 100%/100%, infinite/infinite, and 0.8/0.9 for the halo sign.
The halo sign showed 100% specificity for GCA but only 10%-17% sensitivity. Stenoses/occlusions were of low diagnostic value. These observations suggest that TA-US is neither an effective substitute for TAB nor a reliable screening test to decide which patients can be safely spared TAB.
The Journal of Rheumatology 11/2010; 37(11):2326-30. · 3.69 Impact Factor
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ABSTRACT: Adrenocortical carcinoma (ACC) is a rare, severe disease. Pregnancy-associated ACC has rarely been reported. We wished to evaluate the characteristics and prognosis of ACC diagnosed in patients during pregnancy or in the postpartum period, comparing them with those for ACC diagnosed in nonpregnant women.
Clinical presentation, hormonal secretion, staging, survival, and obstetric data are reported. Patients were included between 1963 and 2007. Mean follow-up was 48 months.
This is a retrospective cohort study carried out at a referral center. All female patients aged 16-49 years diagnosed with ACC during the observation period were included (n=110). Twelve of these women were pregnant or in the first 6 months after delivery. Hormonal secretion, staging, obstetric data, and survival were analyzed. For the survival analysis, pregnant patients were compared with a subgroup of nonpregnant women matched for age, stage, and year of diagnosis (1 pregnant patient/2 controls).
Adrenocortical tumors diagnosed during pregnancy or in the postpartum period tend to be more often cortisol-secreting tumors (P=0.06) and to be discovered at a more advanced stage than those in nonpregnant women, although the differences were not significant. Fetal outcome was poor. Overall survival of the mother was worse than that of matched controls (hazard ratio of death: 3.98, confidence interval=1.34-11.85, P=0.013).
ACC diagnosed during pregnancy or in the postpartum period is associated with a poor fetal outcome and a poorer prognosis than ACC diagnosed in nonpregnant women.
European Journal of Endocrinology 11/2010; 163(5):793-800. · 3.42 Impact Factor
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ABSTRACT: Although in most patients with WG, induction therapy leads to complete remission (CR), the high relapse rate remains a major problem. This study was undertaken to identify potential predictors of these relapses.
WG outcomes of patients included in two randomized trials were analysed. Patients were categorized into a predominant form of the disease using a scoring system composed of three granulomatous criteria (ear, nose and throat manifestations; lung nodules; and orbital pseudotumour) and three vascular criteria (serum creatinine >125 µmol/l, haematuria or proteinuria and alveolar haemorrhage).
Among 174 patients, 152 (87%) entered CR with CSs and CYC. The risk of death was higher for the vascular form [odds ratio (OR) 3.5 (95% CI 1.1, 11.4)]. With a median follow-up of 50 months, 66 out of 152 patients experienced a relapse (5-year relapse rate: 49%). Multivariate analysis retained the following variables at diagnosis as independent predictors of relapse: specific cardiac involvement [hazard ratio (HR) 2.9 (95% CI 1.3, 6.5)], ANCA with cytoplasmic-labelling pattern (c-ANCA) [HR 2.1 (95% CI 1.1, 4.3)] and higher age [HR 1.4 (95% CI 1.1, 1.7)]. Conversely, severe renal insufficiency was associated with a lower relapse rate [HR 0.4 (95% CI, 0.2-0.8)]. Comparing predominant granulomatous vs predominant vascular disease, relapses were more frequent and earlier with decreasing risk over time.
Increased risk of first WG relapse after initial remission appears to be related to heart involvement, age and c-ANCA positivity at onset. Predominant granulomatous presentation disease seems to be associated with poorer outcomes after CR. These findings may help adapt treatment strategies.
Rheumatology (Oxford, England) 11/2010; 49(11):2181-90. · 4.24 Impact Factor
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ABSTRACT: To further document the measurement properties of each domain of the OA of knee and hip quality of life (OAKHQOL) questionnaire by a Rasch analysis.
The OAKHQOL self-administered questionnaire has been developed to assess health-related quality of life in lower limb OA. Patients with various degrees of severity of knee or hip OA answered the questionnaire. For each domain, their responses to the items were analysed with a Rasch family model, the partial credit model. We examined the fit of data to model expectations, as well as assumptions of unidimensionality and local independence. Invariance was assessed by analysis of differential item functioning (DIF) by sex, age and joint. Analyses used the RUMM2020 software (Rumm Laboratory, Perth, Western Australia).
Responses for 544 patients were analysed: 297 had medically managed OA and 247 were waiting for arthroplasty surgery. For the 40 items of the OAKHQOL, data analysis showed 5 with disordered thresholds and 9 with DIF (5 for joint, 3 for sex and 1 for age). Ten pairs of items showed local dependence and four domains showed unidimensionality. Full-item domains and domains without the misfitted items did not differ in patient-estimates data; therefore any bias at the item level is negligible when considering the domain scores.
The five domains of the OAKHQOL questionnaire show good measurement properties by Rasch analysis and provide valid scales.
Rheumatology (Oxford, England) 11/2010; 50(3):500-5. · 4.24 Impact Factor
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ABSTRACT: 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.
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.
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.
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.
Quality of Life Research 10/2010; 20(2):287-300. · 2.30 Impact Factor
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Rossella Libé, Joël Coste,
Laurence Guignat,
Frédérique Tissier,
Hervé Lefebvre,
Gaëlle Barrande,
Christiane Ajzenberg,
Igor Tauveron,
Eric Clauser,
Bertrand Dousset,
Xavier Bertagna,
Jérôme Bertherat,
Lionel Groussin
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ABSTRACT: ACTH-independent macronodular adrenal hyperplasia (AIMAH) is a rare and heterogeneous condition characterized by abnormal steroid production. Cortisol secretion can be regulated by aberrant hormone receptors.
A large series of patients with AIMAH were evaluated to provide information on the prevalence and profile of aberrant regulations, in relation with the functional status.
Thirty-two consecutive patients with AIMAH were prospectively studied: 10 had a Cushing's syndrome (CS), and 22 had a subclinical CS (SCS).
A baseline endocrine evaluation was followed by an in vivo protocol in search of aberrant cortisol responses (seven provocative tests). An acute inhibition test with the somatostatin analog octreotide was also performed.
At least one aberrant cortisol response was identified in 28 of 32 (87%) patients. The overall prevalence of aberrant responses was independent of the functional status. Responses to the upright posture and to metoclopramide were frequently observed (67 and 56% respectively). A glucagon response was frequently observed in the SCS group (58%). A cortisol inhibition by octreotide was specifically found in the three CS patients who positively responded to the mixed meal, and was observed also in 12 of 13 (92%) patients with SCS.
Cortisol responses indicative of aberrant receptor expression were highly prevalent in AIMAH. Thorough phenotyping of AIMAH may help uncover the underlying pathophysiology.
European Journal of Endocrinology 04/2010; 163(1):129-38. · 3.42 Impact Factor
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ABSTRACT: Context: Effective treatment for the ectopic ACTH secretion syndrome (EAS) remains a therapeutic challenge. Immediate curative surgery of the responsible nonpituitary tumor is often not possible. Objective: The objective of the study was to evaluate 1,ortho-1, para'-dichloro-diphenyl-dichloro-ethane (O,p'DDD) therapy in EAS. Design and Patients: Patients included 36 consecutive patients with EAS from a single center treated between 1990 and 2006. Twenty-three of these patients, including 18 women aged 53.7 +/- 12.9 yr (mean +/- sd), were treated with O,p'DDD. Patient follow-up was 8.04 +/- 9.6 yr. Results: A mean daily O,p'DDD dose of 3.3 +/- 1.2 g Lysodren equivalent was given for a mean duration of 1.8 +/- 2.1 yr. Urinary cortisol decreased from 2603 +/- 3443 microg/d before treatment to 79 +/- 169 microg/d at the time of maximal O,p'DDD efficacy. Urinary cortisol was normalized in 21 of the 23 patients. Adrenal insufficiency was observed in 20 patients. This was associated with clinical improvement of Cushing's syndrome manifestations, including diabetes, hypertension, and hypokalemia. O,p'DDD plasma levels were 10.4 +/- 6.5 microg/ml in the 12 patients tested at the time of adrenal insufficiency. Side effects were observed during the first 6 months in seven of 15 patients (46%). National Cancer Institute-Classification Common Toxicity Criteria grade 1 or 2 digestive or neurologic toxicity resolved after withdrawal or reduction of O,p'DDD. Careful monitoring was essential to long-term control, clinical improvement, and good tolerability. Medical control of the disease allowed the subsequent characterization of tumors in eight of 13 patients with initially occult tumors. Conclusion: With close monitoring, O,p'DDD could be a potent medical treatment for long-term control and management of EAS.
The Journal of clinical endocrinology and metabolism 02/2010; 95(2):537-44. · 6.50 Impact Factor
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ABSTRACT: Missing items are common in quality of life (QoL) questionnaires and present a challenge for research in this field. The development of sound strategies of replacement and prevention requires accurate knowledge of their type and determinants.
We used the 2003 French Decennial Health Survey of a representative sample of the general population--including 22,620 adult subjects who completed the SF-36 questionnaire--to test various socio-demographic, health status and QoL variables as potential predictors of missingness. We constructed logistic regression models for each SF-36 item to identify independent predictors and classify them according to Little and Rubin ("missing completely at random", "missing at random" and "missing not at random").
The type of missingness was missing at random for half of the items of the SF-36 and missing not at random for the others. None of the items were missing completely at random. Independent predictors of missingness were age, female sex, low scores on the SF-36 subscales and in some cases low educational level, occupation, nationality and poor health status.
This study of the SF-36 shows that imputation of missing items is necessary and emphasizes several factors for missingness that should be considered in prevention strategies of missing data. Similar methodologies could be applied to item missingness in other QoL questionnaires.
Health and Quality of Life Outcomes 01/2010; 8:16. · 2.11 Impact Factor
