Presentation of continuous outcomes in randomised trials: an observational study.
OBJECTIVE: To characterise the percentage of available outcome data being presented in reports of randomised clinical trials with continuous outcome measures, thereby determining the potential for incomplete reporting bias. DESIGN: Descriptive cross sectional study. DATA SOURCES: A random sample of...
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| Format: | Journal article |
| Language: | English |
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2012
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| _version_ | 1797091067648016384 |
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| author | Schriger, D Savage, D Altman, D |
| author_facet | Schriger, D Savage, D Altman, D |
| author_sort | Schriger, D |
| collection | OXFORD |
| description | OBJECTIVE: To characterise the percentage of available outcome data being presented in reports of randomised clinical trials with continuous outcome measures, thereby determining the potential for incomplete reporting bias. DESIGN: Descriptive cross sectional study. DATA SOURCES: A random sample of 200 randomised trials from issues of 20 medical journals in a variety of specialties during 2007-09. MAIN OUTCOME MEASURES: For each paper's best reported primary outcome, we calculated the fraction of data reported using explicit scoring rules. For example, a two arm trial with 100 patients per limb that reported 2 sample sizes, 2 means, and 2 standard deviations reported 6/200 data elements (1.5%), but if that paper included a scatterplot with 200 points it would score 200/200 (100%). We also assessed compliance with 2001 CONSORT items about the reporting of results. RESULTS: The median percentage of data reported for the best reported continuous outcome was 9% (interquartile range 3-26%) but only 3.5% (3-7%) when we adjusted studies to 100 patients per arm to control for varying study size; 17% of articles showed 100% of the data. Tables were the predominant means of presenting the most data (59% of articles), but papers that used figures reported a higher proportion of data. There was substantial heterogeneity among journals with respect to our primary outcome and CONSORT compliance. LIMITATIONS: We studied continuous outcomes of randomised trials in higher impact journals. Results may not apply to categorical outcomes, other study designs, or other journals. CONCLUSIONS: Trialists present only a small fraction of available data. This paucity of data may increase the potential for incomplete reporting bias, a failure to present all relevant information about a study's findings. |
| first_indexed | 2024-03-07T03:27:45Z |
| format | Journal article |
| id | oxford-uuid:b9a510fc-a8ed-44ff-95bb-ba246d7d658c |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T03:27:45Z |
| publishDate | 2012 |
| record_format | dspace |
| spelling | oxford-uuid:b9a510fc-a8ed-44ff-95bb-ba246d7d658c2022-03-27T05:04:16ZPresentation of continuous outcomes in randomised trials: an observational study.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:b9a510fc-a8ed-44ff-95bb-ba246d7d658cEnglishSymplectic Elements at Oxford2012Schriger, DSavage, DAltman, DOBJECTIVE: To characterise the percentage of available outcome data being presented in reports of randomised clinical trials with continuous outcome measures, thereby determining the potential for incomplete reporting bias. DESIGN: Descriptive cross sectional study. DATA SOURCES: A random sample of 200 randomised trials from issues of 20 medical journals in a variety of specialties during 2007-09. MAIN OUTCOME MEASURES: For each paper's best reported primary outcome, we calculated the fraction of data reported using explicit scoring rules. For example, a two arm trial with 100 patients per limb that reported 2 sample sizes, 2 means, and 2 standard deviations reported 6/200 data elements (1.5%), but if that paper included a scatterplot with 200 points it would score 200/200 (100%). We also assessed compliance with 2001 CONSORT items about the reporting of results. RESULTS: The median percentage of data reported for the best reported continuous outcome was 9% (interquartile range 3-26%) but only 3.5% (3-7%) when we adjusted studies to 100 patients per arm to control for varying study size; 17% of articles showed 100% of the data. Tables were the predominant means of presenting the most data (59% of articles), but papers that used figures reported a higher proportion of data. There was substantial heterogeneity among journals with respect to our primary outcome and CONSORT compliance. LIMITATIONS: We studied continuous outcomes of randomised trials in higher impact journals. Results may not apply to categorical outcomes, other study designs, or other journals. CONCLUSIONS: Trialists present only a small fraction of available data. This paucity of data may increase the potential for incomplete reporting bias, a failure to present all relevant information about a study's findings. |
| spellingShingle | Schriger, D Savage, D Altman, D Presentation of continuous outcomes in randomised trials: an observational study. |
| title | Presentation of continuous outcomes in randomised trials: an observational study. |
| title_full | Presentation of continuous outcomes in randomised trials: an observational study. |
| title_fullStr | Presentation of continuous outcomes in randomised trials: an observational study. |
| title_full_unstemmed | Presentation of continuous outcomes in randomised trials: an observational study. |
| title_short | Presentation of continuous outcomes in randomised trials: an observational study. |
| title_sort | presentation of continuous outcomes in randomised trials an observational study |
| work_keys_str_mv | AT schrigerd presentationofcontinuousoutcomesinrandomisedtrialsanobservationalstudy AT savaged presentationofcontinuousoutcomesinrandomisedtrialsanobservationalstudy AT altmand presentationofcontinuousoutcomesinrandomisedtrialsanobservationalstudy |