LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 14

Search options

  1. Article: A Dangerous Curve: Impact of the COVID-19 Pandemic on Brace Treatment in Adolescent Idiopathic Scoliosis.

    Pereira Duarte, Matias / Joncas, Julie / Parent, Stefan / Duval, Mylène / Chémaly, Olivier / Brassard, Félix / Mac-Thiong, Jean-Marc / Barchi, Soraya / Labelle, Hubert

    Global spine journal

    2022  Volume 14, Issue 2, Page(s) 513–518

    Abstract: Study design: Observational Cohort study.: Objectives: We aim to document the abandon and irregular compliance rate towards brace treatment during the COVID-19 pandemic and its impact on AIS progression.: Methods: We reviewed a database of AIS ... ...

    Abstract Study design: Observational Cohort study.
    Objectives: We aim to document the abandon and irregular compliance rate towards brace treatment during the COVID-19 pandemic and its impact on AIS progression.
    Methods: We reviewed a database of AIS patients recruited between March and September 2020. We included AIS patients under brace treatment according to SRS criteria. The patients were divided in 2 cohorts: those with self-reported Good-Compliance (GC) to treatment and those who had a Bad-Compliance (BC). Data analysis included biometric and radiographic data at first visit and last follow-up and percentage of progression. Unpaired student-t tests and Chi
    Results: 152 patients met inclusion criteria. 89 patients (age:12.1y.o.±1.4) reported good adherence to treatment, while 63 patients (age:12.7y.o.±1.8) were not compliant. Within the BC group, 18 patients reported irregular brace wear, while 45 had completely abandoned treatment (abandon rate of 29%). The GC cohort started treatment with a mean main thoracic (MT) curve of 26° and finished with 27°. The mean difference between measurements was +.65°±7.5; mean progression rate was -
    Conclusion: The abandon rate of brace treatment in AIS significantly increased during the first wave of COVID-19 pandemic. Patients who voluntarily discontinued treatment had significant increases in curve progression and surgical indication rates.
    Level of evidence: III.
    Language English
    Publishing date 2022-07-11
    Publishing country England
    Document type Journal Article
    ZDB-ID 2648287-3
    ISSN 2192-5690 ; 2192-5682
    ISSN (online) 2192-5690
    ISSN 2192-5682
    DOI 10.1177/21925682221113487
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article ; Online: Nightmare frequency, nightmare distress, and psychopathology in female victims of childhood maltreatment.

    Duval, Mylène / McDuff, Pierre / Zadra, Antonio

    The Journal of nervous and mental disease

    2013  Volume 201, Issue 9, Page(s) 767–772

    Abstract: This study investigated the relationships between a history of childhood maltreatment, the frequency of disturbing dreams, their associated distress, and the presence of psychopathology in 352 female undergraduate volunteers. Participants completed ... ...

    Abstract This study investigated the relationships between a history of childhood maltreatment, the frequency of disturbing dreams, their associated distress, and the presence of psychopathology in 352 female undergraduate volunteers. Participants completed questionnaires assessing dream recall, bad dream and nightmare frequency, nightmare distress, psychological well-being, and history of childhood trauma. Four groups were investigated based on the type and severity of childhood maltreatments experienced. Women reporting more severe forms of maltreatment reported higher frequencies of disturbing dreams, higher levels of nightmare distress, and greater psychopathology. Results showed that nightmare distress explains frequency of disturbed dreaming beyond the effect of psychopathology and childhood trauma. The results highlight the importance of assessing waking distress associated with disturbing dreams independently from their actual incidence.
    MeSH term(s) Adolescent ; Anxiety Disorders/diagnosis ; Anxiety Disorders/epidemiology ; Anxiety Disorders/psychology ; Child Abuse/diagnosis ; Child Abuse/psychology ; Child Abuse/statistics & numerical data ; Child Abuse, Sexual/diagnosis ; Child Abuse, Sexual/psychology ; Child Abuse, Sexual/statistics & numerical data ; Cross-Sectional Studies ; Depressive Disorder/diagnosis ; Depressive Disorder/epidemiology ; Depressive Disorder/psychology ; Dreams/psychology ; Female ; Humans ; Mental Recall ; Models, Psychological ; Psychopathology ; Statistics as Topic ; Surveys and Questionnaires ; Young Adult
    Language English
    Publishing date 2013-09
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 3020-x
    ISSN 1539-736X ; 0022-3018
    ISSN (online) 1539-736X
    ISSN 0022-3018
    DOI 10.1097/NMD.0b013e3182a214a1
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article ; Online: Analysis of a simulated microarray dataset

    Mouzaki Daphné / Marot Guillemette / Lê Cao Kim-Anh / Lavrič Miha / Jiménez-Marín Ángeles / Jaffrézic Florence / Hulsegge Ina / Garrido-Pavón Juan / Foulley Jean-Louis / Duval Mylène / Dovč Peter / Delmas Céline / Baron Michael / Pérez-Alegre Mónica / Watson Michael / Pool Marco H / Robert-Granié Christèle / San Cristobal Magali / Tosser-Klopp Gwenola /
    Waddington David / de Koning Dirk-Jan

    Genetics Selection Evolution, Vol 39, Iss 6, Pp 669-

    Comparison of methods for data normalisation and detection of differential expression ( Open Access publication )

    2007  Volume 683

    Abstract: Abstract Microarrays allow researchers to measure the expression of thousands of genes in a single experiment. Before statistical comparisons can be made, the data must be assessed for quality and normalisation procedures must be applied, of which many ... ...

    Abstract Abstract Microarrays allow researchers to measure the expression of thousands of genes in a single experiment. Before statistical comparisons can be made, the data must be assessed for quality and normalisation procedures must be applied, of which many have been proposed. Methods of comparing the normalised data are also abundant, and no clear consensus has yet been reached. The purpose of this paper was to compare those methods used by the EADGENE network on a very noisy simulated data set. With the a priori knowledge of which genes are differentially expressed, it is possible to compare the success of each approach quantitatively. Use of an intensity-dependent normalisation procedure was common, as was correction for multiple testing. Most variety in performance resulted from differing approaches to data quality and the use of different statistical tests. Very few of the methods used any kind of background correction. A number of approaches achieved a success rate of 95% or above, with relatively small numbers of false positives and negatives. Applying stringent spot selection criteria and elimination of data did not improve the false positive rate and greatly increased the false negative rate. However, most approaches performed well, and it is encouraging that widely available techniques can achieve such good results on a very noisy data set.
    Keywords gene expression ; two colour microarray ; simulation ; statistical analysis ; Genetics ; QH426-470 ; Biology (General) ; QH301-705.5 ; Science ; Q ; DOAJ:Genetics ; DOAJ:Biology ; DOAJ:Biology and Life Sciences
    Subject code 310
    Language English
    Publishing date 2007-11-01T00:00:00Z
    Publisher BioMed Central
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  4. Article: Analysis of a simulated microarray dataset: comparison of methods for data normalisation and detection of differential expression (open access publication).

    Watson, Michael / Pérez-Alegre, Mónica / Baron, Michael Denis / Delmas, Céline / Dovc, Peter / Duval, Mylène / Foulley, Jean-Louis / Garrido-Pavón, Juan José / Hulsegge, Ina / Jaffrézic, Florence / Jiménez-Marín, Angeles / Lavric, Miha / Lê Cao, Kim-Anh / Marot, Guillemette / Mouzaki, Daphné / Pool, Marco H / Robert-Granié, Christèle / San Cristobal, Magali / Tosser-Klopp, Gwenola /
    Waddington, David / de Koning, Dirk-Jan

    Genetics, selection, evolution : GSE

    2007  Volume 39, Issue 6, Page(s) 669–683

    Abstract: Microarrays allow researchers to measure the expression of thousands of genes in a single experiment. Before statistical comparisons can be made, the data must be assessed for quality and normalisation procedures must be applied, of which many have been ... ...

    Abstract Microarrays allow researchers to measure the expression of thousands of genes in a single experiment. Before statistical comparisons can be made, the data must be assessed for quality and normalisation procedures must be applied, of which many have been proposed. Methods of comparing the normalised data are also abundant, and no clear consensus has yet been reached. The purpose of this paper was to compare those methods used by the EADGENE network on a very noisy simulated data set. With the a priori knowledge of which genes are differentially expressed, it is possible to compare the success of each approach quantitatively. Use of an intensity-dependent normalisation procedure was common, as was correction for multiple testing. Most variety in performance resulted from differing approaches to data quality and the use of different statistical tests. Very few of the methods used any kind of background correction. A number of approaches achieved a success rate of 95% or above, with relatively small numbers of false positives and negatives. Applying stringent spot selection criteria and elimination of data did not improve the false positive rate and greatly increased the false negative rate. However, most approaches performed well, and it is encouraging that widely available techniques can achieve such good results on a very noisy data set.
    MeSH term(s) Animals ; Animals, Domestic/genetics ; Computer Simulation ; Data Interpretation, Statistical ; Databases, Genetic ; Europe ; Gene Expression Profiling/statistics & numerical data ; Oligonucleotide Array Sequence Analysis/statistics & numerical data ; Software
    Language English
    Publishing date 2007-12-06
    Publishing country France
    Document type Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1005838-2
    ISSN 0999-193X
    ISSN 0999-193X
    DOI 10.1186/1297-9686-39-6-669
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Article ; Online: Analysis of the real EADGENE data set

    Schuberth Hans-Joachim / van Schothorst Evert M / Lund Mogens / San Cristobal Magali / Robert-Granié Christèle / Pool Marco H / Petzl Wolfram / Nie Haisheng / Cao Kim-Anh / de Koning Dirk-Jan / Jiang Li / Jensen Kirsty / Hulsegge Ina / Jaffrézic Florence / Hornshøj Henrik / Hedegaard Jakob / Glass Liz / Duval Mylène / Delmas Céline /
    Déjean Sébastien / Closset Rodrigue / Buitenhuis Bart / Bonnet Agnès / Sørensen Peter / Seyfert Hans-Martin / Tosser-Klopp Gwenola / Waddington David / Watson Michael / Yang Wei / Zerbe Holm

    Genetics Selection Evolution, Vol 39, Iss 6, Pp 651-

    Multivariate approaches and post analysis ( Open Access publication )

    2007  Volume 668

    Abstract: Abstract The aim of this paper was to describe, and when possible compare, the multivariate methods used by the participants in the EADGENE WP1.4 workshop. The first approach was for class discovery and class prediction using evidence from the data at ... ...

    Abstract Abstract The aim of this paper was to describe, and when possible compare, the multivariate methods used by the participants in the EADGENE WP1.4 workshop. The first approach was for class discovery and class prediction using evidence from the data at hand. Several teams used hierarchical clustering (HC) or principal component analysis (PCA) to identify groups of differentially expressed genes with a similar expression pattern over time points and infective agent ( E. coli or S. aureus ). The main result from these analyses was that HC and PCA were able to separate tissue samples taken at 24 h following E. coli infection from the other samples. The second approach identified groups of differentially co-expressed genes, by identifying clusters of genes highly correlated when animals were infected with E. coli but not correlated more than expected by chance when the infective pathogen was S. aureus . The third approach looked at differential expression of predefined gene sets. Gene sets were defined based on information retrieved from biological databases such as Gene Ontology. Based on these annotation sources the teams used either the GlobalTest or the Fisher exact test to identify differentially expressed gene sets. The main result from these analyses was that gene sets involved in immune defence responses were differentially expressed.
    Keywords bovine annotation ; bovine microarray ; gene set analysis ; mastitis ; multivariate approaches ; Genetics ; QH426-470 ; Biology (General) ; QH301-705.5 ; Science ; Q ; DOAJ:Genetics ; DOAJ:Biology ; DOAJ:Biology and Life Sciences
    Subject code 570
    Language English
    Publishing date 2007-11-01T00:00:00Z
    Publisher BioMed Central
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  6. Article: Analysis of the real EADGENE data set: multivariate approaches and post analysis (open access publication).

    Sørensen, Peter / Bonnet, Agnès / Buitenhuis, Bart / Closset, Rodrigue / Déjean, Sébastien / Delmas, Céline / Duval, Mylène / Glass, Liz / Hedegaard, Jakob / Hornshøj, Henrik / Hulsegge, Ina / Jaffrézic, Florence / Jensen, Kirsty / Jiang, Li / de Koning, Dirk-Jan / Lê Cao, Kim-Anh / Nie, Haisheng / Petzl, Wolfram / Pool, Marco H /
    Robert-Granié, Christèle / San Cristobal, Magali / Lund, Mogens Sandø / van Schothorst, Evert M / Schuberth, Hans-Joachim / Seyfert, Hans-Martin / Tosser-Klopp, Gwenola / Waddington, David / Watson, Michael / Yang, Wei / Zerbe, Holm

    Genetics, selection, evolution : GSE

    2007  Volume 39, Issue 6, Page(s) 651–668

    Abstract: The aim of this paper was to describe, and when possible compare, the multivariate methods used by the participants in the EADGENE WP1.4 workshop. The first approach was for class discovery and class prediction using evidence from the data at hand. ... ...

    Abstract The aim of this paper was to describe, and when possible compare, the multivariate methods used by the participants in the EADGENE WP1.4 workshop. The first approach was for class discovery and class prediction using evidence from the data at hand. Several teams used hierarchical clustering (HC) or principal component analysis (PCA) to identify groups of differentially expressed genes with a similar expression pattern over time points and infective agent (E. coli or S. aureus). The main result from these analyses was that HC and PCA were able to separate tissue samples taken at 24 h following E. coli infection from the other samples. The second approach identified groups of differentially co-expressed genes, by identifying clusters of genes highly correlated when animals were infected with E. coli but not correlated more than expected by chance when the infective pathogen was S. aureus. The third approach looked at differential expression of predefined gene sets. Gene sets were defined based on information retrieved from biological databases such as Gene Ontology. Based on these annotation sources the teams used either the GlobalTest or the Fisher exact test to identify differentially expressed gene sets. The main result from these analyses was that gene sets involved in immune defence responses were differentially expressed.
    MeSH term(s) Animals ; Animals, Domestic/genetics ; Cattle/genetics ; Data Interpretation, Statistical ; Databases, Genetic ; Escherichia coli Infections/genetics ; Escherichia coli Infections/veterinary ; Europe ; Female ; Gene Expression Profiling/statistics & numerical data ; Host-Pathogen Interactions/genetics ; Mastitis, Bovine/genetics ; Multivariate Analysis ; Oligonucleotide Array Sequence Analysis/statistics & numerical data ; Staphylococcal Infections/genetics ; Staphylococcal Infections/veterinary
    Language English
    Publishing date 2007-12-06
    Publishing country France
    Document type Comparative Study ; Congress ; Research Support, Non-U.S. Gov't
    ZDB-ID 1005838-2
    ISSN 0999-193X
    ISSN 0999-193X
    DOI 10.1186/1297-9686-39-6-651
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  7. Article ; Online: Analysis of the real EADGENE data set

    Sørensen Peter / Schuberth Hans-Joachim / van Schothorst Evert M / San Cristobal Magali / Robert-Granié Christèle / Pool Marco H / Petzl Wolfram / Nie Haisheng / Marot Guillemette / Malinverni Roberto / Lund Mogens / Cao Kim-Anh / Lavrič Miha / Jiang Li / Jensen Kirsty / Janss Luc / Hulsegge Ina / Hornshøj Henrik / Hedegaard Jakob /
    Foulley Jean-Louis / Duval Mylène / Dovč Peter / Detilleux Johanne C / Delmas Céline / Déjean Sébastien / Closset Rodrigue / Buitenhuis Bart / Bonnet Agnès / Boettcher Paul J / de Koning Dirk-Jan / Jaffrézic Florence / Stella Alessandra / Tosser-Klopp Gwenola / Waddington David / Watson Michael / Yang Wei / Zerbe Holm / Seyfert Hans-Martin

    Genetics Selection Evolution, Vol 39, Iss 6, Pp 633-

    Comparison of methods and guidelines for data normalisation and selection of differentially expressed genes ( Open Access publication )

    2007  Volume 650

    Abstract: Abstract A large variety of methods has been proposed in the literature for microarray data analysis. The aim of this paper was to present techniques used by the EADGENE (European Animal Disease Genomics Network of Excellence) WP1.4 participants for data ...

    Abstract Abstract A large variety of methods has been proposed in the literature for microarray data analysis. The aim of this paper was to present techniques used by the EADGENE (European Animal Disease Genomics Network of Excellence) WP1.4 participants for data quality control, normalisation and statistical methods for the detection of differentially expressed genes in order to provide some more general data analysis guidelines. All the workshop participants were given a real data set obtained in an EADGENE funded microarray study looking at the gene expression changes following artificial infection with two different mastitis causing bacteria: Escherichia coli and Staphylococcus aureus . It was reassuring to see that most of the teams found the same main biological results. In fact, most of the differentially expressed genes were found for infection by E. coli between uninfected and 24 h challenged udder quarters. Very little transcriptional variation was observed for the bacteria S. aureus . Lists of differentially expressed genes found by the different research teams were, however, quite dependent on the method used, especially concerning the data quality control step. These analyses also emphasised a biological problem of cross-talk between infected and uninfected quarters which will have to be dealt with for further microarray studies.
    Keywords quality control ; differentially expressed genes ; mastitis resistance ; microarray data ; normalisation ; Genetics ; QH426-470 ; Biology (General) ; QH301-705.5 ; Science ; Q ; DOAJ:Genetics ; DOAJ:Biology ; DOAJ:Biology and Life Sciences
    Subject code 310
    Language English
    Publishing date 2007-11-01T00:00:00Z
    Publisher BioMed Central
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  8. Article: Analysis of the real EADGENE data set: comparison of methods and guidelines for data normalisation and selection of differentially expressed genes (open access publication).

    Jaffrézic, Florence / de Koning, Dirk-Jan / Boettcher, Paul J / Bonnet, Agnès / Buitenhuis, Bart / Closset, Rodrigue / Déjean, Sébastien / Delmas, Céline / Detilleux, Johanne C / Dovc, Peter / Duval, Mylène / Foulley, Jean-Louis / Hedegaard, Jakob / Hornshøj, Henrik / Hulsegge, Ina / Janss, Luc / Jensen, Kirsty / Jiang, Li / Lavric, Miha /
    Lê Cao, Kim-Anh / Lund, Mogens Sandø / Malinverni, Roberto / Marot, Guillemette / Nie, Haisheng / Petzl, Wolfram / Pool, Marco H / Robert-Granié, Christèle / San Cristobal, Magali / van Schothorst, Evert M / Schuberth, Hans-Joachim / Sørensen, Peter / Stella, Alessandra / Tosser-Klopp, Gwenola / Waddington, David / Watson, Michael / Yang, Wei / Zerbe, Holm / Seyfert, Hans-Martin

    Genetics, selection, evolution : GSE

    2007  Volume 39, Issue 6, Page(s) 633–650

    Abstract: A large variety of methods has been proposed in the literature for microarray data analysis. The aim of this paper was to present techniques used by the EADGENE (European Animal Disease Genomics Network of Excellence) WP1.4 participants for data quality ... ...

    Abstract A large variety of methods has been proposed in the literature for microarray data analysis. The aim of this paper was to present techniques used by the EADGENE (European Animal Disease Genomics Network of Excellence) WP1.4 participants for data quality control, normalisation and statistical methods for the detection of differentially expressed genes in order to provide some more general data analysis guidelines. All the workshop participants were given a real data set obtained in an EADGENE funded microarray study looking at the gene expression changes following artificial infection with two different mastitis causing bacteria: Escherichia coli and Staphylococcus aureus. It was reassuring to see that most of the teams found the same main biological results. In fact, most of the differentially expressed genes were found for infection by E. coli between uninfected and 24 h challenged udder quarters. Very little transcriptional variation was observed for the bacteria S. aureus. Lists of differentially expressed genes found by the different research teams were, however, quite dependent on the method used, especially concerning the data quality control step. These analyses also emphasised a biological problem of cross-talk between infected and uninfected quarters which will have to be dealt with for further microarray studies.
    MeSH term(s) Analysis of Variance ; Animals ; Animals, Domestic/genetics ; Bias ; Cattle/genetics ; Data Interpretation, Statistical ; Databases, Genetic ; Escherichia coli Infections/genetics ; Escherichia coli Infections/veterinary ; Europe ; Female ; Gene Expression Profiling/standards ; Gene Expression Profiling/statistics & numerical data ; Guidelines as Topic ; Mastitis, Bovine/genetics ; Oligonucleotide Array Sequence Analysis/standards ; Oligonucleotide Array Sequence Analysis/statistics & numerical data ; Quality Control ; Software ; Staphylococcal Infections/genetics ; Staphylococcal Infections/veterinary
    Language English
    Publishing date 2007-12-06
    Publishing country France
    Document type Comparative Study ; Congress ; Research Support, Non-U.S. Gov't
    ZDB-ID 1005838-2
    ISSN 0999-193X
    ISSN 0999-193X
    DOI 10.1186/1297-9686-39-6-633
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  9. Article: Analysis of a simulated microarray dataset : Comparison of methods for data normalisation and detection of differential expression

    Watson, Michael / Pérez-Alegre, Monica / Baron, Michael Denis / Delmas, Celine / Dovc, Peter / Duval, Mylene / Foulley, Jean Louis / Garrido-Pavon, Juan José / Hulsegge, Ina / Jaffrézic, Florence / Jiménez-Marin, Angeles / Lavric, Miha / Lê Cao, Kim-Anh / Marot, Guillemette / Mouzaki, Daphné / Pool, M.H. / Robert Granié, Christèle / San Cristobal, Magali / Tosser-Klopp, Gwenola /
    Waddington, David / Koning, Dirk-Jan

    Genetics Selection Evolution 6 (39), 669-683. (2007)

    Abstract: Microarrays allow researchers to measure the expression of thousands of genes in a single experiment. Before statistical comparisons can be made, the data must be assessed for quality and normalisation procedures must be applied, of which many have been ... ...

    Abstract Microarrays allow researchers to measure the expression of thousands of genes in a single experiment. Before statistical comparisons can be made, the data must be assessed for quality and normalisation procedures must be applied, of which many have been proposed.Methods of comparing the normalised data are also abundant, and no clear consensus has yetbeen reached. The purpose of this paper was to compare those methods used by the EADGENE network on a very noisy simulated data set. With the a priori knowledge of which genes are differentially expressed, it is possible to compare the success of each approach quantitatively. Use of an intensity-dependent normalisation procedure was common, as was correction for multiple testing. Most variety in performance resulted from differing approaches to data quality and the use of different statistical tests. Very few of the methods used any kind of background correction. A number of approaches achieved a success rate of 95% or above, with relatively small numbers of false positives and negatives. Applying stringent spot selection criteria and elimination of data did not improve the false positive rate and greatly increased the false negative rate. However, most approaches performed well, and it is encouraging that widely available techniques can achieve such good results on a very noisy data set.
    Language English
    Document type Article
    Database AGRIS - International Information System for the Agricultural Sciences and Technology

    More links

    Kategorien

  10. Article: Analysis of a simulated microarray dataset : Comparison of methods for data normalisation and detection of differential expression

    Watson, Michael / Pérez-Alegre, Monica / Baron, Michael Denis / Delmas, Celine / Dovc, Peter / Duval, Mylene / Foulley, Jean Louis / Garrido-Pavon, Juan José / Hulsegge, Ina / Jaffrézic, Florence / Jiménez-Marin, Angeles / Lavric, Miha / Lê Cao, Kim-Anh / Marot, Guillemette / Mouzaki, Daphné / Pool, M.H. / Robert Granié, Christèle / San Cristobal, Magali / Tosser-Klopp, Gwenola /
    Waddington, David / Koning, Dirk-Jan

    Genetics Selection Evolution 6 (39), 669-683. (2007)

    Abstract: Microarrays allow researchers to measure the expression of thousands of genes in a single experiment. Before statistical comparisons can be made, the data must be assessed for quality and normalisation procedures must be applied, of which many have been ... ...

    Abstract Microarrays allow researchers to measure the expression of thousands of genes in a single experiment. Before statistical comparisons can be made, the data must be assessed for quality and normalisation procedures must be applied, of which many have been proposed.Methods of comparing the normalised data are also abundant, and no clear consensus has yetbeen reached. The purpose of this paper was to compare those methods used by the EADGENE network on a very noisy simulated data set. With the a priori knowledge of which genes are differentially expressed, it is possible to compare the success of each approach quantitatively. Use of an intensity-dependent normalisation procedure was common, as was correction for multiple testing. Most variety in performance resulted from differing approaches to data quality and the use of different statistical tests. Very few of the methods used any kind of background correction. A number of approaches achieved a success rate of 95% or above, with relatively small numbers of false positives and negatives. Applying stringent spot selection criteria and elimination of data did not improve the false positive rate and greatly increased the false negative rate. However, most approaches performed well, and it is encouraging that widely available techniques can achieve such good results on a very noisy data set.
    Language English
    Document type Article
    Database AGRIS - International Information System for the Agricultural Sciences and Technology

    More links

    Kategorien

To top