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Primary versus secondary source of data in observational studies and heterogeneity in meta-analyses of drug effects: a survey of major medical journals

Overview of attention for article published in BMC Medical Research Methodology, September 2018
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  • In the top 25% of all research outputs scored by Altmetric
  • Good Attention Score compared to outputs of the same age (69th percentile)

Mentioned by

blogs
1 blog

Citations

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4 Dimensions

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mendeley
67 Mendeley
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Title
Primary versus secondary source of data in observational studies and heterogeneity in meta-analyses of drug effects: a survey of major medical journals
Published in
BMC Medical Research Methodology, September 2018
DOI 10.1186/s12874-018-0561-3
Pubmed ID
Authors

Guillermo Prada-Ramallal, Fatima Roque, Maria Teresa Herdeiro, Bahi Takkouche, Adolfo Figueiras

Abstract

The data from individual observational studies included in meta-analyses of drug effects are collected either from ad hoc methods (i.e. "primary data") or databases that were established for non-research purposes (i.e. "secondary data"). The use of secondary sources may be prone to measurement bias and confounding due to over-the-counter and out-of-pocket drug consumption, or non-adherence to treatment. In fact, it has been noted that failing to consider the origin of the data as a potential cause of heterogeneity may change the conclusions of a meta-analysis. We aimed to assess to what extent the origin of data is explored as a source of heterogeneity in meta-analyses of observational studies. We searched for meta-analyses of drugs effects published between 2012 and 2018 in general and internal medicine journals with an impact factor > 15. We evaluated, when reported, the type of data source (primary vs secondary) used in the individual observational studies included in each meta-analysis, and the exposure- and outcome-related variables included in sensitivity, subgroup or meta-regression analyses. We found 217 articles, 23 of which fulfilled our eligibility criteria. Eight meta-analyses (8/23, 34.8%) reported the source of data. Three meta-analyses (3/23, 13.0%) included the method of outcome assessment as a variable in the analysis of heterogeneity, and only one compared and discussed the results considering the different sources of data (primary vs secondary). In meta-analyses of drug effects published in seven high impact general medicine journals, the origin of the data, either primary or secondary, is underexplored as a source of heterogeneity.

Mendeley readers

The data shown below were compiled from readership statistics for 67 Mendeley readers of this research output. Click here to see the associated Mendeley record.

Geographical breakdown

Country Count As %
Unknown 67 100%

Demographic breakdown

Readers by professional status Count As %
Student > Master 18 27%
Student > Bachelor 10 15%
Student > Ph. D. Student 5 7%
Researcher 4 6%
Other 3 4%
Other 3 4%
Unknown 24 36%
Readers by discipline Count As %
Business, Management and Accounting 9 13%
Social Sciences 8 12%
Nursing and Health Professions 6 9%
Medicine and Dentistry 6 9%
Pharmacology, Toxicology and Pharmaceutical Science 3 4%
Other 10 15%
Unknown 25 37%

Attention Score in Context

This research output has an Altmetric Attention Score of 6. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 28 September 2018.
All research outputs
#3,177,212
of 13,568,727 outputs
Outputs from BMC Medical Research Methodology
#450
of 1,251 outputs
Outputs of similar age
#80,016
of 265,071 outputs
Outputs of similar age from BMC Medical Research Methodology
#1
of 1 outputs
Altmetric has tracked 13,568,727 research outputs across all sources so far. Compared to these this one has done well and is in the 76th percentile: it's in the top 25% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 1,251 research outputs from this source. They typically receive more attention than average, with a mean Attention Score of 8.9. This one has gotten more attention than average, scoring higher than 60% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 265,071 tracked outputs that were published within six weeks on either side of this one in any source. This one has gotten more attention than average, scoring higher than 69% of its contemporaries.
We're also able to compare this research output to 1 others from the same source and published within six weeks on either side of this one. This one has scored higher than all of them