{"id":{"repo_id":"aachen","oai_identifier":"oai:publications.rwth-aachen.de:63188"},"canonical_url":"https://search.dev.ndltd.org/etd/aachen/oai:publications.rwth-aachen.de:63188","repository":{"repo_id":"aachen","name":"RWTH Aachen University","base_url":"https://publications.rwth-aachen.de/oai2d"},"display":{"title":"Zur analytischen und medizinischen Bewertung der nicht-invasiven multiparametrischen Bestimmung der Leberfibrose und -fibrogenese am Beispiel von Fibrotest und Actitest","abstract":"BACKGROUND: Determining the stage and grade of liver- fibrosis by liver biopsy is important in managing patients with liver diseases causing fibrosis. Commercially Biopredictive provides per internet non- invasive analytical tests (Fibrotest, Actitest) for diagnosis of liver- fibrosis. AIMS: To evaluate non- invasive methods for analytical determination of liver- fibrosis using the example of Fibrotest an Actitest, in terms of the influence of inter- and intra- laboratory analytical variabilities. Biopredictive disposes of an not released algorithm. METHODS: On the one hand the investigations of Fibrotest and Actitest based on quality validated findings of interlaboratory tests of INSTAND and DGKL. Still permitted limits of permissible errors of analytes were used in different combinations for the calculations. 64 tests were performed. One the other hand serum from 4 confirmed hepatitis C patients with liver fibrosis was analysed in six laboratories for the required sample components. The calculated grade and stage of fibrosis by Fibrotest and Actitest were compared with biopsy results.RESULTS: The 64 calculations of Fibrotest showed a spread of a distribution from F2-F4. Actitest results were similar in spreading, from A1-A2 to A3. The interlaboratory reproducibility of the 4 patient sera could almost be achieved, but there was a big discrepancy between biopsy results and the Actitest/ Fibrotest calculations. Test results could not validate the verified grade and stage of fibrosis. The error rate was 77% (Fibrotest) and 73% (Actitest).CONCLUSION: The influence of analytical variability on Fibrotest and Actitest cannot assure a correct diagnosis of fibrosis. Even the validity put the tests into question.","abstract_html":"BACKGROUND: Determining the stage and grade of liver- fibrosis by liver biopsy is important in managing patients with liver diseases causing fibrosis. Commercially Biopredictive provides per internet non- invasive analytical tests (Fibrotest, Actitest) for diagnosis of liver- fibrosis. AIMS: To evaluate non- invasive methods for analytical determination of liver- fibrosis using the example of Fibrotest an Actitest, in terms of the influence of inter- and intra- laboratory analytical variabilities. Biopredictive disposes of an not released algorithm. METHODS: On the one hand the investigations of Fibrotest and Actitest based on quality validated findings of interlaboratory tests of INSTAND and DGKL. Still permitted limits of permissible errors of analytes were used in different combinations for the calculations. 64 tests were performed. One the other hand serum from 4 confirmed hepatitis C patients with liver fibrosis was analysed in six laboratories for the required sample components. The calculated grade and stage of fibrosis by Fibrotest and Actitest were compared with biopsy results.RESULTS: The 64 calculations of Fibrotest showed a spread of a distribution from F2-F4. Actitest results were similar in spreading, from A1-A2 to A3. The interlaboratory reproducibility of the 4 patient sera could almost be achieved, but there was a big discrepancy between biopsy results and the Actitest/ Fibrotest calculations. Test results could not validate the verified grade and stage of fibrosis. The error rate was 77% (Fibrotest) and 73% (Actitest).CONCLUSION: The influence of analytical variability on Fibrotest and Actitest cannot assure a correct diagnosis of fibrosis. Even the validity put the tests into question.","abstract_has_math":false,"creators":["Beer, Nina"],"institution":"Publikationsserver der RWTH Aachen University","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Gressner, Olav A."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009","date_published":"2009","updated_at":"2026-07-30T19:43:35Z","subjects":["info:eu-repo/classification/ddc/610","Leberfibrose","Medizin","Nicht-invasive Leberfibrosediagnostik","Actitest","Fibrotest","liver fibrosis"],"languages":["ger"],"rights":["info:eu-repo/semantics/openAccess"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124639%22"],"render_values":[{"text":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124639%22","href":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124639%22","code":true}]}]},"links":{"outbound_url":"https://publications.rwth-aachen.de/record/63188","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Gressner, Olav A."]},{"key":"dc:creator","label":"Author","values":["Beer, Nina"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:coverage","label":"Dc Coverage","values":["DE"]},{"key":"dc:date","label":"Dc Date","values":["2009"]},{"key":"dc:publisher","label":"Institution","values":["Publikationsserver der RWTH Aachen University"]},{"key":"dc:relation","label":"Dc Relation","values":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-33362"]},{"key":"dc:type","label":"Dc Type","values":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["info:eu-repo/classification/ddc/610","Leberfibrose","Medizin","Nicht-invasive Leberfibrosediagnostik","Actitest","Fibrotest","liver fibrosis"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["ger"]},{"key":"dc:rights","label":"Dc Rights","values":["info:eu-repo/semantics/openAccess"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/record/63188","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124639%22"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["BACKGROUND: Determining the stage and grade of liver- fibrosis by liver biopsy is important in managing patients with liver diseases causing fibrosis. Commercially Biopredictive provides per internet non- invasive analytical tests (Fibrotest, Actitest) for diagnosis of liver- fibrosis. AIMS: To evaluate non- invasive methods for analytical determination of liver- fibrosis using the example of Fibrotest an Actitest, in terms of the influence of inter- and intra- laboratory analytical variabilities. Biopredictive disposes of an not released algorithm. METHODS: On the one hand the investigations of Fibrotest and Actitest based on quality validated findings of interlaboratory tests of INSTAND and DGKL. Still permitted limits of permissible errors of analytes were used in different combinations for the calculations. 64 tests were performed. One the other hand serum from 4 confirmed hepatitis C patients with liver fibrosis was analysed in six laboratories for the required sample components. The calculated grade and stage of fibrosis by Fibrotest and Actitest were compared with biopsy results.RESULTS: The 64 calculations of Fibrotest showed a spread of a distribution from F2-F4. Actitest results were similar in spreading, from A1-A2 to A3. The interlaboratory reproducibility of the 4 patient sera could almost be achieved, but there was a big discrepancy between biopsy results and the Actitest/ Fibrotest calculations. Test results could not validate the verified grade and stage of fibrosis. The error rate was 77% (Fibrotest) and 73% (Actitest).CONCLUSION: The influence of analytical variability on Fibrotest and Actitest cannot assure a correct diagnosis of fibrosis. Even the validity put the tests into question."]},{"key":"dc:source","label":"Dc Source","values":["Aachen : Publikationsserver der RWTH Aachen University V, 66 S. : graph. Darst. (2009). = Aachen, Techn. Hochsch., Diss., 2009"]},{"key":"dc:title","label":"Title","values":["Zur analytischen und medizinischen Bewertung der nicht-invasiven multiparametrischen Bestimmung der Leberfibrose und -fibrogenese am Beispiel von Fibrotest und Actitest"]}]}],"canonical_facts":{"dc:contributor":["Gressner, Olav A."],"dc:coverage":["DE"],"dc:creator":["Beer, Nina"],"dc:date":["2009"],"dc:description":["BACKGROUND: Determining the stage and grade of liver- fibrosis by liver biopsy is important in managing patients with liver diseases causing fibrosis. Commercially Biopredictive provides per internet non- invasive analytical tests (Fibrotest, Actitest) for diagnosis of liver- fibrosis. AIMS: To evaluate non- invasive methods for analytical determination of liver- fibrosis using the example of Fibrotest an Actitest, in terms of the influence of inter- and intra- laboratory analytical variabilities. Biopredictive disposes of an not released algorithm. METHODS: On the one hand the investigations of Fibrotest and Actitest based on quality validated findings of interlaboratory tests of INSTAND and DGKL. Still permitted limits of permissible errors of analytes were used in different combinations for the calculations. 64 tests were performed. One the other hand serum from 4 confirmed hepatitis C patients with liver fibrosis was analysed in six laboratories for the required sample components. The calculated grade and stage of fibrosis by Fibrotest and Actitest were compared with biopsy results.RESULTS: The 64 calculations of Fibrotest showed a spread of a distribution from F2-F4. Actitest results were similar in spreading, from A1-A2 to A3. The interlaboratory reproducibility of the 4 patient sera could almost be achieved, but there was a big discrepancy between biopsy results and the Actitest/ Fibrotest calculations. Test results could not validate the verified grade and stage of fibrosis. The error rate was 77% (Fibrotest) and 73% (Actitest).CONCLUSION: The influence of analytical variability on Fibrotest and Actitest cannot assure a correct diagnosis of fibrosis. Even the validity put the tests into question."],"dc:identifier":["https://publications.rwth-aachen.de/record/63188","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124639%22"],"dc:language":["ger"],"dc:publisher":["Publikationsserver der RWTH Aachen University"],"dc:relation":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-33362"],"dc:rights":["info:eu-repo/semantics/openAccess"],"dc:source":["Aachen : Publikationsserver der RWTH Aachen University V, 66 S. : graph. Darst. (2009). = Aachen, Techn. Hochsch., Diss., 2009"],"dc:subject":["info:eu-repo/classification/ddc/610","Leberfibrose","Medizin","Nicht-invasive Leberfibrosediagnostik","Actitest","Fibrotest","liver fibrosis"],"dc:title":["Zur analytischen und medizinischen Bewertung der nicht-invasiven multiparametrischen Bestimmung der Leberfibrose und -fibrogenese am Beispiel von Fibrotest und Actitest"],"dc:type":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]},"updated_at":"2026-07-30T19:43:35Z"}