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Multiple Comparison of Age Groups in Bone Mineral Density under Heteroscedasticity
Osteoporosis is a silent disease because individuals may not know that they have osteoporosis until their bones become so fragile. Bone mineral density (BMD) test helps to detect osteoporosis and determine the risk fractures. This study covers bone measurement data from total body dual energy X-ray...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Hindawi Publishing Corporation
2015
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4564616/ https://www.ncbi.nlm.nih.gov/pubmed/26446707 http://dx.doi.org/10.1155/2015/426847 |
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author | Sezer, Ahmet Altan, Lale Özdemir, Özer |
author_facet | Sezer, Ahmet Altan, Lale Özdemir, Özer |
author_sort | Sezer, Ahmet |
collection | PubMed |
description | Osteoporosis is a silent disease because individuals may not know that they have osteoporosis until their bones become so fragile. Bone mineral density (BMD) test helps to detect osteoporosis and determine the risk fractures. This study covers bone measurement data from total body dual energy X-ray absorptiometry scans for 28,454 persons who participated in the 1996–2006 National Health and Nutrition Examination Survey in USA Dual energy X-ray absorptiometry (DXA) method is known as the primary method for detecting osteoporosis because of its high precision and accuracy. Testing the equality of the means of normal populations when the variances are unknown and unequal is a fundamental problem in clinical trials and biomedical research. In this study we compare age groups based upon BMD in case of unequal variance being present among the groups. First we test equality of variances among the age groups by the Hartley test. And then Scott-Smith test is used to test equality of BMD means for the age groups. Finally, Tukey-Cramer confidence intervals are constructed to detect which groups start to differ from the reference group in which BMD reaches the peak level. |
format | Online Article Text |
id | pubmed-4564616 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | Hindawi Publishing Corporation |
record_format | MEDLINE/PubMed |
spelling | pubmed-45646162015-10-07 Multiple Comparison of Age Groups in Bone Mineral Density under Heteroscedasticity Sezer, Ahmet Altan, Lale Özdemir, Özer Biomed Res Int Research Article Osteoporosis is a silent disease because individuals may not know that they have osteoporosis until their bones become so fragile. Bone mineral density (BMD) test helps to detect osteoporosis and determine the risk fractures. This study covers bone measurement data from total body dual energy X-ray absorptiometry scans for 28,454 persons who participated in the 1996–2006 National Health and Nutrition Examination Survey in USA Dual energy X-ray absorptiometry (DXA) method is known as the primary method for detecting osteoporosis because of its high precision and accuracy. Testing the equality of the means of normal populations when the variances are unknown and unequal is a fundamental problem in clinical trials and biomedical research. In this study we compare age groups based upon BMD in case of unequal variance being present among the groups. First we test equality of variances among the age groups by the Hartley test. And then Scott-Smith test is used to test equality of BMD means for the age groups. Finally, Tukey-Cramer confidence intervals are constructed to detect which groups start to differ from the reference group in which BMD reaches the peak level. Hindawi Publishing Corporation 2015 2015-08-27 /pmc/articles/PMC4564616/ /pubmed/26446707 http://dx.doi.org/10.1155/2015/426847 Text en Copyright © 2015 Ahmet Sezer et al. https://creativecommons.org/licenses/by/3.0/ This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Research Article Sezer, Ahmet Altan, Lale Özdemir, Özer Multiple Comparison of Age Groups in Bone Mineral Density under Heteroscedasticity |
title | Multiple Comparison of Age Groups in Bone Mineral Density under Heteroscedasticity |
title_full | Multiple Comparison of Age Groups in Bone Mineral Density under Heteroscedasticity |
title_fullStr | Multiple Comparison of Age Groups in Bone Mineral Density under Heteroscedasticity |
title_full_unstemmed | Multiple Comparison of Age Groups in Bone Mineral Density under Heteroscedasticity |
title_short | Multiple Comparison of Age Groups in Bone Mineral Density under Heteroscedasticity |
title_sort | multiple comparison of age groups in bone mineral density under heteroscedasticity |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4564616/ https://www.ncbi.nlm.nih.gov/pubmed/26446707 http://dx.doi.org/10.1155/2015/426847 |
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