Relevant analyses
AltraBio offers its expertise in statistics to support your clinical research projects from conception to publication.
Our statisticians have extensive experience in the analysis of medical data covering different therapeutic areas including (but not limited to) neuropsychiatry, neurosciences, pulmonology, immunology, dermatology, cardiology and rheumatology.
We adapt our solutions to the specific needs of our clients: human and veterinary pharmaceutical companies, medical device manufacturers, biotechs, cosmetic and nutritional industries and academic laboratories, from the development phases to the “Post Market Clinical Folow 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
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}
}
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.
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}
}
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].
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].
2021
Rives, Sarah; Schmid, Bruno; Chaumet, Guillaume; Brégeon, Fabienne; Boussuges, Alain
Changes in Diaphragmatic Function Induced by an Increased Inspiratory Load Experienced by Military Divers: An Ultrasound Study Journal Article
In: Front Physiol, vol. 12, pp. 756533, 2021, ISSN: 1664-042X.
@article{pmid34916955b,
title = {Changes in Diaphragmatic Function Induced by an Increased Inspiratory Load Experienced by Military Divers: An Ultrasound Study},
author = {Sarah Rives and Bruno Schmid and Guillaume Chaumet and Fabienne Brégeon and Alain Boussuges},
doi = {10.3389/fphys.2021.756533},
issn = {1664-042X},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
journal = {Front Physiol},
volume = {12},
pages = {756533},
abstract = { Inspiratory loading is experienced by military divers when they use rebreather device. Our objective was to assess the changes in diaphragm function induced by an increase in inspiratory load at values similar to those experienced by divers in real life. : We recorded the excursion and the thickness of the right hemidiaphragm in 22 healthy male volunteers under inspiratory load conditions, using ultrasound in B- and M-mode. The measurements were performed at tidal volume and during breathing at 50% of inspiratory capacity. The breathing rate was regulated and similar in the various sessions with and without load. The rebreather device used by French military divers leads to an increase in inspiratory load of close to 30 cmHO. Consequently, the session under load was performed using a device set to this threshold. Significant increases in the excursion and the thickening fraction of the diaphragm were observed between the sessions at tidal volume and at high volume. With addition of the inspiratory load, the excursion of the right hemidiaphragm increased significantly from 2.3 to 3.4cm at tidal volume and from 3.9 to 4.7cm at high volume. The thickening fraction increased significantly from 30.4 to 76.6% at tidal volume and from 70 to 123% at high volume. The statistical analysis demonstrated that assessment of the changes of the thickening fraction during breathing at tidal volume was the most relevant marker to assess the impact of the inspiratory load on the diaphragm. Diaphragm ultrasound can be used to assess the changes in the diaphragm contraction pattern secondary to an increase in the respiratory load that can be generated by use a diving apparatus. The recording of the changes of the motion, and more importantly of the thickness of the diaphragm, during the breathing cycle is able to provide relevant information regarding the inspiratory load.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Inspiratory loading is experienced by military divers when they use rebreather device. Our objective was to assess the changes in diaphragm function induced by an increase in inspiratory load at values similar to those experienced by divers in real life. : We recorded the excursion and the thickness of the right hemidiaphragm in 22 healthy male volunteers under inspiratory load conditions, using ultrasound in B- and M-mode. The measurements were performed at tidal volume and during breathing at 50% of inspiratory capacity. The breathing rate was regulated and similar in the various sessions with and without load. The rebreather device used by French military divers leads to an increase in inspiratory load of close to 30 cmHO. Consequently, the session under load was performed using a device set to this threshold. Significant increases in the excursion and the thickening fraction of the diaphragm were observed between the sessions at tidal volume and at high volume. With addition of the inspiratory load, the excursion of the right hemidiaphragm increased significantly from 2.3 to 3.4cm at tidal volume and from 3.9 to 4.7cm at high volume. The thickening fraction increased significantly from 30.4 to 76.6% at tidal volume and from 70 to 123% at high volume. The statistical analysis demonstrated that assessment of the changes of the thickening fraction during breathing at tidal volume was the most relevant marker to assess the impact of the inspiratory load on the diaphragm. Diaphragm ultrasound can be used to assess the changes in the diaphragm contraction pattern secondary to an increase in the respiratory load that can be generated by use a diving apparatus. The recording of the changes of the motion, and more importantly of the thickness of the diaphragm, during the breathing cycle is able to provide relevant information regarding the inspiratory load.