Relevant analyses
AltraBio provides statistical expertise to assist with your clinical research projects from inception to publication.
Our statisticians possess extensive experience in analyzing medical data across various therapeutic areas including (but not limited to) neuropsychiatry, neurosciences, pulmonology, immunology, dermatology, cardiology, and rheumatology.
We tailor our solutions to meet the specific needs of our clients, which include human and veterinary pharmaceutical companies, medical device manufacturers, biotechs, cosmetic and nutritional industries, and academic laboratories. Our services span from the development phases to post-market clinical follow-up.
Study design
- Sample size and power calculation
- Writing of the synopsis
- Definition of the analysis methodology
- Development of the Statistical Analysis Plan
Data collection
- Support for writing the Data Management Plan
- Selection of the eCRF
Data processing
- Data extraction
- Formatting in accordance with the standards (CDISC, …)
- Data correction and cleaning (atypical data, missing data, …)
Data Analysis and valorization
- Descriptive methods, comparative analyses, …
- Construction of explanatory or predictive models, …
- Delivery of statistical reports in the form of a pdf or of a dynamic web page, processing algorithms
- Writing of abstracts, posters, research articles
Our Publications In Medical Data Analysis
2023
Boussuges, Alain; Chaumet, Guillaume; Boussuges, Martin; Menard, Amelie; Delliaux, Stephane; Brégeon, Fabienne
Ultrasound assessment of the respiratory system using diaphragm motion-volume indices Journal Article
In: Front Med (Lausanne), vol. 10, pp. 1190891, 2023, ISSN: 2296-858X.
@article{pmid37275363,
title = {Ultrasound assessment of the respiratory system using diaphragm motion-volume indices},
author = {Alain Boussuges and Guillaume Chaumet and Martin Boussuges and Amelie Menard and Stephane Delliaux and Fabienne Brégeon},
doi = {10.3389/fmed.2023.1190891},
issn = {2296-858X},
year = {2023},
date = {2023-05-19},
urldate = {2023-05-19},
journal = {Front Med (Lausanne)},
volume = {10},
pages = {1190891},
abstract = {BACKGROUND: Although previous studies have determined limit values of normality for diaphragm excursion and thickening, it would be beneficial to determine the normal diaphragm motion-to-inspired volume ratio that integrates the activity of the diaphragm and the quality of the respiratory system.
METHODS: To determine the normal values of selected ultrasound diaphragm motion-volume indices, subjects with normal pulmonary function testing were recruited. Ultrasound examination recorded diaphragm excursion on both sides during quiet breathing and deep inspiration. Diaphragm thickness was also measured. The inspired volumes of the corresponding cycles were systematically recorded using a spirometer. The indices were calculated using the ratio excursion, or percentage of thickening, divided by the corresponding breathing volume. From this corhort, normal values and limit values for normality were determined. These measurements were compared to those performed on the healthy side in patients with hemidiaphragm paralysis because an increase in hemidiaphragm activity has been previously demonstated in such circumstances.
RESULTS: A total of 122 subjects (51 women, 71 men) with normal pulmonary function were included in the study. Statistical analysis revealed that the ratio of excursion, or percentage of thickening, to inspired volume ratio significantly differed between males and females. When the above-mentioned indices using excursion were normalized by body weight, no gender differences were found. The indices differed between normal respiratory function subjects and patients with hemidiaphragm paralysis (27 women, 41 men). On the paralyzed side, the average ratio of the excursion divided by the inspired volume was zero. On the healthy side, the indices using the excursion and the percentage of thickening during quiet breathing or deep inspiration were significantly increased comparedto patients with normal lung function. According to the logistic regression analysis, the most relevant indice appeared to be the ratio of the excursion measured during quiet breathing to the inspired volume.
CONCLUSION: The normal values of the diaphragm motion-volume indices could be useful to estimate the performance of the respiratory system. Proposed indices appear suitable in a context of hyperactivity.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
METHODS: To determine the normal values of selected ultrasound diaphragm motion-volume indices, subjects with normal pulmonary function testing were recruited. Ultrasound examination recorded diaphragm excursion on both sides during quiet breathing and deep inspiration. Diaphragm thickness was also measured. The inspired volumes of the corresponding cycles were systematically recorded using a spirometer. The indices were calculated using the ratio excursion, or percentage of thickening, divided by the corresponding breathing volume. From this corhort, normal values and limit values for normality were determined. These measurements were compared to those performed on the healthy side in patients with hemidiaphragm paralysis because an increase in hemidiaphragm activity has been previously demonstated in such circumstances.
RESULTS: A total of 122 subjects (51 women, 71 men) with normal pulmonary function were included in the study. Statistical analysis revealed that the ratio of excursion, or percentage of thickening, to inspired volume ratio significantly differed between males and females. When the above-mentioned indices using excursion were normalized by body weight, no gender differences were found. The indices differed between normal respiratory function subjects and patients with hemidiaphragm paralysis (27 women, 41 men). On the paralyzed side, the average ratio of the excursion divided by the inspired volume was zero. On the healthy side, the indices using the excursion and the percentage of thickening during quiet breathing or deep inspiration were significantly increased comparedto patients with normal lung function. According to the logistic regression analysis, the most relevant indice appeared to be the ratio of the excursion measured during quiet breathing to the inspired volume.
CONCLUSION: The normal values of the diaphragm motion-volume indices could be useful to estimate the performance of the respiratory system. Proposed indices appear suitable in a context of hyperactivity.
2022
Evangelista, Teresinha; Kandji, Malick; Lacene, Emmanuelle; Chanut, Anaïs; Bui, Mai Thao; Marty, Rudy; Buffat, Laurent; Knoblauch, Kenneth; Rudkin, Brian B; Romero, Norma Beatriz
Comprehensive morphometric assessment of deltoid muscle development in children: A cross-sectional study Journal Article
In: EBioMedicine, vol. 86, pp. 104367, 2022, ISSN: 2352-3964.
@article{pmid36410115,
title = {Comprehensive morphometric assessment of deltoid muscle development in children: A cross-sectional study},
author = {Teresinha Evangelista and Malick Kandji and Emmanuelle Lacene and Anaïs Chanut and Mai Thao Bui and Rudy Marty and Laurent Buffat and Kenneth Knoblauch and Brian B Rudkin and Norma Beatriz Romero},
doi = {10.1016/j.ebiom.2022.104367},
issn = {2352-3964},
year = {2022},
date = {2022-12-01},
urldate = {2022-12-01},
journal = {EBioMedicine},
volume = {86},
pages = {104367},
abstract = {BACKGROUND: Normative values for different morphometric parameters of muscle fibres during paediatric development, i.e. from 0 to 18 years, are currently unavailable. They would be of major importance to accurately evaluate pathological changes and could be used as reference biomarkers for evaluating treatment response in clinical trials, or physiological adjustments in sports or ageing.
METHODS: Data were derived from 482 images with a total of 33 094 fibres from 10 μm cross-sections of snap-frozen muscle from 83 deltoid muscle biopsies from patients, 0-18 years, without neuromuscular pathology stained with ATPase 9.4. Data was acquired and analysed with patented image analysis algorithms from "CARPACCIO.cloud". Several parameters were extracted or calculated, including cross-sectional area (CSA), fibre type, circularity, as well as the Minimum diameter of Feret (MinFeret).
FINDINGS: This study illustrates changes in quantitative parameters for muscle morphology over the course of paediatric development and the pivotal changes occurring around puberty. Only fibre size parameters (MinFeret, CSA) are dependent on gender, and only after puberty. All other parameters vary in a similar manner for females and males. The proportion of type 1 fibres is essentially constant from birth to age 10, decreasing to ≈40% by age 18. Circularity decreases with age, to plateau after age 10 for both fibre types.
INTERPRETATION: Normative values and reference charts for muscle fibre types in this age range have been generated to allow comparison of data from patients in pathology laboratories working on neuromuscular diseases.
FUNDING: BPI FRANCE, PULSALYS, Association de l'Institut de Myologie, French National Research Agency (ANR), LABEX CORTEX of Université de Lyon.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
METHODS: Data were derived from 482 images with a total of 33 094 fibres from 10 μm cross-sections of snap-frozen muscle from 83 deltoid muscle biopsies from patients, 0-18 years, without neuromuscular pathology stained with ATPase 9.4. Data was acquired and analysed with patented image analysis algorithms from "CARPACCIO.cloud". Several parameters were extracted or calculated, including cross-sectional area (CSA), fibre type, circularity, as well as the Minimum diameter of Feret (MinFeret).
FINDINGS: This study illustrates changes in quantitative parameters for muscle morphology over the course of paediatric development and the pivotal changes occurring around puberty. Only fibre size parameters (MinFeret, CSA) are dependent on gender, and only after puberty. All other parameters vary in a similar manner for females and males. The proportion of type 1 fibres is essentially constant from birth to age 10, decreasing to ≈40% by age 18. Circularity decreases with age, to plateau after age 10 for both fibre types.
INTERPRETATION: Normative values and reference charts for muscle fibre types in this age range have been generated to allow comparison of data from patients in pathology laboratories working on neuromuscular diseases.
FUNDING: BPI FRANCE, PULSALYS, Association de l'Institut de Myologie, French National Research Agency (ANR), LABEX CORTEX of Université de Lyon.
Boussuges, Alain; Habert, Paul; Chaumet, Guillaume; Rouibah, Rawah; Delorme, Lea; Menard, Amelie; Million, Matthieu; Bartoli, Axel; Guedj, Eric; Gouitaa, Marion; Zieleskiewicz, Laurent; Finance, Julie; Coiffard, Benjamin; Delliaux, Stephane; Brégeon, Fabienne
Diaphragm dysfunction after severe COVID-19: An ultrasound study Journal Article
In: Front Med (Lausanne), vol. 9, pp. 949281, 2022, ISSN: 2296-858X.
@article{pmid36091672,
title = {Diaphragm dysfunction after severe COVID-19: An ultrasound study},
author = {Alain Boussuges and Paul Habert and Guillaume Chaumet and Rawah Rouibah and Lea Delorme and Amelie Menard and Matthieu Million and Axel Bartoli and Eric Guedj and Marion Gouitaa and Laurent Zieleskiewicz and Julie Finance and Benjamin Coiffard and Stephane Delliaux and Fabienne Brégeon},
doi = {10.3389/fmed.2022.949281},
issn = {2296-858X},
year = {2022},
date = {2022-01-01},
urldate = {2022-01-01},
journal = {Front Med (Lausanne)},
volume = {9},
pages = {949281},
abstract = {BACKGROUND: SARS-CoV-2 infection can impair diaphragm function at the acute phase but the frequency of diaphragm dysfunction after recovery from COVID-19 remains unknown.
MATERIALS AND METHODS: This study was carried out on patients reporting persistent respiratory symptoms 3-4 months after severe COVID-19 pneumonia. The included patients were selected from a medical consultation designed to screen for recovery after acute infection. Respiratory function was assessed by a pulmonary function test, and diaphragm function was studied by ultrasonography.
RESULTS: In total, 132 patients (85M, 47W) were recruited from the medical consultation. During the acute phase of the infection, the severity of the clinical status led to ICU admission for 58 patients (44%). Diaphragm dysfunction (DD) was detected by ultrasonography in 13 patients, two of whom suffered from hemidiaphragm paralysis. Patients with DD had more frequently muscle pain complaints and had a higher frequency of prior cardiothoracic or upper abdominal surgery than patients with normal diaphragm function. Pulmonary function testing revealed a significant decrease in lung volumes and DLCO and the dyspnea scores (mMRC and Borg10 scores) were significantly increased in patients with DD. Improvement in respiratory function was recorded in seven out of nine patients assessed 6 months after the first ultrasound examination.
CONCLUSION: Assessment of diaphragm function by ultrasonography after severe COVID-19 pneumonia revealed signs of dysfunction in 10% of our population. In some cases, ultrasound examination probably discovered an un-recognized pre-existing DD. COVID-19 nonetheless contributed to impairment of diaphragm function. Prolonged respiratory physiotherapy led to improvement in respiratory function in most patients.
CLINICAL TRIAL REGISTRATION: [www.cnil.fr], identifier [#PADS20-207].},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
MATERIALS AND METHODS: This study was carried out on patients reporting persistent respiratory symptoms 3-4 months after severe COVID-19 pneumonia. The included patients were selected from a medical consultation designed to screen for recovery after acute infection. Respiratory function was assessed by a pulmonary function test, and diaphragm function was studied by ultrasonography.
RESULTS: In total, 132 patients (85M, 47W) were recruited from the medical consultation. During the acute phase of the infection, the severity of the clinical status led to ICU admission for 58 patients (44%). Diaphragm dysfunction (DD) was detected by ultrasonography in 13 patients, two of whom suffered from hemidiaphragm paralysis. Patients with DD had more frequently muscle pain complaints and had a higher frequency of prior cardiothoracic or upper abdominal surgery than patients with normal diaphragm function. Pulmonary function testing revealed a significant decrease in lung volumes and DLCO and the dyspnea scores (mMRC and Borg10 scores) were significantly increased in patients with DD. Improvement in respiratory function was recorded in seven out of nine patients assessed 6 months after the first ultrasound examination.
CONCLUSION: Assessment of diaphragm function by ultrasonography after severe COVID-19 pneumonia revealed signs of dysfunction in 10% of our population. In some cases, ultrasound examination probably discovered an un-recognized pre-existing DD. COVID-19 nonetheless contributed to impairment of diaphragm function. Prolonged respiratory physiotherapy led to improvement in respiratory function in most patients.
CLINICAL TRIAL REGISTRATION: [www.cnil.fr], identifier [#PADS20-207].