A critical appraisal of epidemiological studies comes from basic knowledge: a reader's guide to assess potential for biases
<p>Abstract</p> <p>Scientific literature may be biased because of the internal validity of studies being compromised by different forms of measurement error, and/or because of the selective reporting of positive and 'statistically significant' results. While the first sou...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2007-03-01
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| Series: | World Journal of Emergency Surgery |
| Online Access: | http://www.wjes.org/content/2/1/7 |
| _version_ | 1811246934460989440 |
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| author | van Duijn Cornelia M D'Ugo Domenico Persiani Roberto La Torre Giuseppe Boccia Stefania Ricciardi Gualtiero |
| author_facet | van Duijn Cornelia M D'Ugo Domenico Persiani Roberto La Torre Giuseppe Boccia Stefania Ricciardi Gualtiero |
| author_sort | van Duijn Cornelia M |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Scientific literature may be biased because of the internal validity of studies being compromised by different forms of measurement error, and/or because of the selective reporting of positive and 'statistically significant' results. While the first source of bias might be prevented, and in some cases corrected to a degree, the second represents a pervasive problem afflicting the medical literature; a situation that can only be 'corrected' by a change in the mindset of authors, reviewers, and editors. This review focuses on the concepts of confounding, selection bias and information bias, utilising explanatory examples and simple rules to recognise and, when possible, to correct for them. Confounding is a mixing of effects resulting from an imbalance of some of the causes of disease across the compared groups. It can be prevented by randomization and restriction, and controlled by stratification, standardization or by using multivariable techniques. Selection bias stems from an absence of comparability among the groups being studied, while information bias arises from distorted information collection techniques. Publication bias of medical research results can invalidate evidence-based medicine, when a researcher attempting to collect all the published studies on a specific topic actually gathers only a proportion of them, usually the ones reporting 'positive' results. The selective publication of 'statistically significant' results represents a problem that researchers and readers have to be aware of in order to face the entire body of published medical evidence with a degree of scepticism.</p> |
| first_indexed | 2024-04-12T15:00:43Z |
| format | Article |
| id | doaj.art-23a142e4b1474604964b417831f4218a |
| institution | Directory Open Access Journal |
| issn | 1749-7922 |
| language | English |
| last_indexed | 2024-04-12T15:00:43Z |
| publishDate | 2007-03-01 |
| publisher | BMC |
| record_format | Article |
| series | World Journal of Emergency Surgery |
| spelling | doaj.art-23a142e4b1474604964b417831f4218a2022-12-22T03:28:05ZengBMCWorld Journal of Emergency Surgery1749-79222007-03-0121710.1186/1749-7922-2-7A critical appraisal of epidemiological studies comes from basic knowledge: a reader's guide to assess potential for biasesvan Duijn Cornelia MD'Ugo DomenicoPersiani RobertoLa Torre GiuseppeBoccia StefaniaRicciardi Gualtiero<p>Abstract</p> <p>Scientific literature may be biased because of the internal validity of studies being compromised by different forms of measurement error, and/or because of the selective reporting of positive and 'statistically significant' results. While the first source of bias might be prevented, and in some cases corrected to a degree, the second represents a pervasive problem afflicting the medical literature; a situation that can only be 'corrected' by a change in the mindset of authors, reviewers, and editors. This review focuses on the concepts of confounding, selection bias and information bias, utilising explanatory examples and simple rules to recognise and, when possible, to correct for them. Confounding is a mixing of effects resulting from an imbalance of some of the causes of disease across the compared groups. It can be prevented by randomization and restriction, and controlled by stratification, standardization or by using multivariable techniques. Selection bias stems from an absence of comparability among the groups being studied, while information bias arises from distorted information collection techniques. Publication bias of medical research results can invalidate evidence-based medicine, when a researcher attempting to collect all the published studies on a specific topic actually gathers only a proportion of them, usually the ones reporting 'positive' results. The selective publication of 'statistically significant' results represents a problem that researchers and readers have to be aware of in order to face the entire body of published medical evidence with a degree of scepticism.</p>http://www.wjes.org/content/2/1/7 |
| spellingShingle | van Duijn Cornelia M D'Ugo Domenico Persiani Roberto La Torre Giuseppe Boccia Stefania Ricciardi Gualtiero A critical appraisal of epidemiological studies comes from basic knowledge: a reader's guide to assess potential for biases World Journal of Emergency Surgery |
| title | A critical appraisal of epidemiological studies comes from basic knowledge: a reader's guide to assess potential for biases |
| title_full | A critical appraisal of epidemiological studies comes from basic knowledge: a reader's guide to assess potential for biases |
| title_fullStr | A critical appraisal of epidemiological studies comes from basic knowledge: a reader's guide to assess potential for biases |
| title_full_unstemmed | A critical appraisal of epidemiological studies comes from basic knowledge: a reader's guide to assess potential for biases |
| title_short | A critical appraisal of epidemiological studies comes from basic knowledge: a reader's guide to assess potential for biases |
| title_sort | critical appraisal of epidemiological studies comes from basic knowledge a reader s guide to assess potential for biases |
| url | http://www.wjes.org/content/2/1/7 |
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