Mendeley Readership Altmetrics for Clinical Medicine and

Engineering?

Ehsan Mohammadi1, Mike Thelwall1, Vincent Larivière2, Stefanie Haustein2

E-mail: e.mohammadi@wlv.ac.uk

1University of Wolverhampton. UK.2Université de Montréal, Montréal, Québec, Canada.

Citation is incomplete

• Limited to authors’ perspectives.(Schloegl & Stock, 2004).

• More appropriate for theoretical publications.

• 3-5 years times are needed for receiving citation

• Citation indicators are not able to give the full picture of research impact

Usage Metrics are tasteful but..

• They mainly employed local usage data.

• Downloaders are unknown.

• Data aggregation is not easy.

Altmetrics as a solution?Altmetrics is a new movement which tries to find complementary measures for traditional metrics based on scholars’ activities in social web platforms (Priem, Taraborelli, Groth, & Neylon, 2011).

Data collection is faster.Data is more accessible.Data coverage is global.Diversity in data type (not limited to authors)

Why Mendeley?

• Massive users

• Diversity of users

• Huge size of database

• Open API

• Global coverage

Research Question

• What proportion of Clinical Medicine and Engineering articles are covered by Mendeley database?

• Are there significant, substantial and positive correlations between Mendeley readership counts and citation measures in Clinical Medicine and Engineering specialties?

Method• Montreal university’s in-house version of the Thomson-ISI databases were used for data collection.

• Based on NSF classification, the most productive specialities of engineering and clinical medicine were selected

• All bibliographic information + citation data of the journal articles of the year 2008 were downloaded.• 145,536 for clinical medicine and 109,390 for engineering.

• Statistics data related to Mendeley readership for the WoS articles were extracted using the Mendeley API.

• The WoS data set and Mendeley readership data were matched and duplications were removed.

• Spearman correlation tests were applied to the ISI citations and Mendeley readership counts.

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% of WoS articles fro 2008 from Clinical Medicine and Engineering specialities in Mendeley

Unique WoS articles covered by Mendeley

Duplicated records in Mendeley catalogue

Articles with readership statistics in Mendeley

Findings

• We considered the coverage in Mendeley for different specialties based on the available unique records in Mendeley catalogue.

• Clinical Medicine articles had the higher coverage (71.6%) in comparison to Engineering and Technology (33.7%) papers.

• 1.5% of the overall founded records of both Engineering and Clinical Medicine were subjected to duplication.

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Spearman correlations between WoS citations and Mendeley readership counts (non-zero only) for 2008 Clinical Medicine and

engineering articles

Findings

• There is a significant correlation between Mendeley readership and citation counts in all the investigated specialities.

• The correlation for clinical medicine overall (r=.561) is higher than for engineering (r=.501).

• Cancer (r=.604) and Materials Science (r=.682) had the highest correlations among clinical medicine and engineering specialties.

• Surgery (r=.451) and Computers (r=.414) had the lowest correlations among Clinical Medicine and Engineering and Technology specialties.

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Comparison of citation and Mendeley readership median for 2008 Clinical Medicine and engineering articles

WoS citation median

Mendeley readership median

Findings

• The median Mendeley readership counts were higher than the median citation counts for mechanical and computer engineering papers.

• This is due to that mechanical and computer engineering papers were read more and citied less.

Limitations

• Readership is limited to the individuals who choose Mendeley for their reference manager.

• Our studied sample is restricted to journal articles while conference papers are important document types in engineering disciplines.

Conclusions

• In almost all disciplines, the correlation is not strong enough to conclude that Mendeley readership and citation counts measure the same aspect of research impact.

• A likely explanation is that Mendeley captures broader scholarly activities from a variety of readers’ perspectives in comparison to citation counts.

• Hence, Mendeley readership data could be a useful supplementary measure to remedy some limitations of citation analysis for some applied specialities.