Table Of ContentInternational
r
comparisons
or
research outputs
Cardiovascular research 198 1— 1991
PRISM
Unitfor Policy Research in Scienceand Medicine
INTERNATIONAL COMPARISONS OF
RESEARCH OUTPUTS
Cardiovascular research 1981-1991
PRISM Report No. 2
& M
Anderson, L Rogers O'Driscoll
J
April 1994
Digitized by the Internet Archive
2014
in
https://archive.org/details/b20456463
CONTENTS
PREFACE
4
SUMMARY
5
INTRODUCTION
1 6
I.I Objectives ofthe study 6
1.2 Background to the cardiovascular study 6
1.3 Assessing research output: a bibliometric approach 7
METHODOLOGY
2 8
2.1 Bibliometric analysis 8
2.2 Defining the field: what constitutes cardiovascular research? 8
2.3 Construction ofa MeSH filter for cardiovascular research 9
2.4 Analysing international trends in cardiovascular research 10
2.5 Analysing cardiovascular research by subfield 11
2.6 Citation analysis - assessing impact 11
2.7 Identifying cardiovascular researchers in the UK 11
RESULTS AND DISCUSSION
3 13
3.1 Cardiovascular research in the biomedical field 13
3.2 International comparisons 13
3.3 Trends in cardiovascular research 14
3.4 The impact ofcardiovascular research 15
3.5 International collaboration in cardiovascular research 16
3.6 International comparison ofthe emphasis on different subfields 17
3.7 Distribution ofcardiovascular research activity in the UK 18
4 CO/~\NXTCLTUTSTCITO/~\NXTSC 22
A 11 Solving the problem offield definition 22
The contribution ofcardiovascular research
to the biomedical field 22
4.3 International comparison ofproductivity 22
4.4 Citation impact ofcardiovascular papers 23
4.5 Prominence ofcardiovascular research 23
4.6 Co-authorship patterns 23
4.7 Cardiovascular research activity in the UK 24
REFERENCES
25
This report presents the findings of a detailed bibliographic analysis of
several thousands of publications in the field of cardiovascular research.
The studywas part ofa larger experimental foresight project on the future
ofcardiovascular research in the UK.
The authors would like to thank the project Steering Committee and
expert advisory group for their valuable contributions to this study
(Dr M B Davis, Professor A Henderson, Professor P Poole-Wilson,
Dr DJulian and Dr L Smaje).
This study was funded by the Wellcome Trust, the British Heart
Foundation and the Medical Research Council.
SUMMARY
This report presents the findings ofa bibliometric study ofcardiovascular
research outputs. The study was part of a wider project on foresight
analysis which included a large-scale survey of scientists on issues
concerning the future ofcardiovascular research in the UK. The analysis
focused on cardiovascular research published in refereed journals and
covered several thousand papers. The five countries considered were the
UK, the USA, Germany, France and Japan. Cardiovascular research
activity in the UK was considered in more detail to identify the most
active institutions and individuals.
A key step was the development ofa novel method to define the field of
cardiovascular research and to identify papers published in this area. The
study employed two data sources - the Science Citation Index (SCI) and
Medline - which together cover thousands of biomedical journals. The
Medical Subject Headings (MeSH) index was used to identify a set of
papers ofrelevance to cardiovascular research. This set was then validated
by an iterative process which incorporated the views ofan expert Steering
Committee.
This process resulted in a definition of the cardiovascular field that
captured basic and clinical research papers drawn from a wide range of
biomedical disciplines, a sample that effectively represented the total
production of papers in this field worldwide. The sample was then
analysed to give information on publishing productivity, impact (as
measured by citations), and collaboration patterns.
Main findings • Ofallbiomedical paperspublishedworldwide, 1 in 5 wasfoundtobe relevantto
cardiovascularresearch.
• The USA dominated cardiovascular research in terms ofthe number ofpapers
published worldwide. Japan was the second most prolific publisher, and in
recent years increased its lead over the UK. However, the UK produced more
cardiovascular papers than did the two other European nations, Germany and
France.
• Cardiovascular research did not stand out as a specially active field within the
UK'snational researchportfolio, unlike inJapanandGermany.
• Japan appears to have conducted little research on cardiovascular surgery and
emphasised researchwith a focusoncardiovascularagents.
• Using citations as a measure ofimpact, the US and UK have had the highest
impact internationally. Citation rates for cardiovascular papers were higher in
these countries than the world norm for this field. In Germany, Japan and
France, however,citation rateswerebelowaverage.
• The UK collaborated more than might be expected with Germany and France,
given the level of research activity in these countries. Geographic proximity
mightbean importantdeterminantin researchcollaboration.
• Within the UK, London dominated cardiovascular research in terms ofactivity
levels. Between 1988 and 1991, 60 ofthe top 100 authors ofcardiovascular
researchwerebasedin thecapital.
5
INTRODUCTION
1.
I.I Objectives ofthe study The study was commissioned by the British Heart Foundation, the
Medical Research Council and the Wellcome Trust, the three main UK
funding bodies with an interest in cardiovascular biology. It aimed to
provide data on the published outputs ofthe UK cardiovascular research
community together with international comparisons. Representatives
from each of the three funding bodies formed a Steering Committee for
the project. They were mainly senior cardiovascular research scientists and
administrators who served as both customers for the project and as a
source ofexpert advice.
The study set out to assess international activity in cardiovascular research
using a bibliometric approach that measured research outputs in the form
of publications. The aim was to look in detail at the output of
cardiovascular research and its place in biomedical research as a whole.
The five countries chosen for inclusion in the study were the UK,
Germany, France, Japan and the USA.
As well as measuring absolute numbers of publications, the study also
aimed to measure the relative importance ofcardiovascular research in the
five countries, to assess the level ofcollaboration between countries and to
UK
review topics ofkey importance. In addition, the cardiovascular scene
was studied in more detail to show areas ofgreatest activity.
.2 Background to the Internationally, cardiovascular disorders are a major health problem in the
1
cardiovascular study developed world.1 In the UK, cardiovascular disease remains the single
most common cause ofdeath. According to the latest available figures in
England and Wales, 'circulatory disease' caused 21% of all deaths in
people up to the age of 65 in 1988.2 The financial cost is also high. In
1986/87, circulatory disease accounted for 13% of National Health
Service expenditure in England and Wales, almost double that ofcancer
and second only to mental illness.3 In Scotland, 4% oftotal NHS costs in
1988 were due to stroke alone.4 It was against this background that
cardiovascular research was selected by the UK Government as a key area
in the 1992 Health of the Nation white paper5 as well as a research and
development priority in the National Health Service.6
In 1990, a Medical Research Council joint working group was set up to
review the biology of cardiovascular disorders. Concluding that future
funding decisions and strategy would have to be based on broader
consultation and more comprehensive data, the group agreed to support
an experimental 'foresight' study in the field of cardiovascular research.
The aim was not to attempt to make predictions as such, but to examine
key areas of research that may be of significance in the future and to
identify trends, nationally and internationally.
6
The work presented here formed part of that larger foresight project on
the future of cardiovascular research in the UK. The foresight project
comprised a number of components, including a poll of expert opinion
on issues of concern to both users and practitioners of cardiovascular
research, the results ofwhich are reported elsewhere.7 This present study
attempted to provide a basis for discussions on the future ofthe field, by
UK
describing previous patterns of research activity in the and
internationally.
1.3 Assessing research output: The most widely employed method ofevaluating research is peer review,
a bibliometric approach in which experts in the field assess the quality ofthe research and identify
strengths and weaknesses.8 Bibliometric analysis provides a mechanism of
supporting this qualitative method of assessment with quantitative data
about research outputs. Several studies have addressed the issue ofhow to
measure outputs,' 17 the most common measures to date being counts of
inventions, patents, publications, citations, prizes and research grants or
contracts.
The work presented in this report employed analysis of research publi-
cations to examine the international output of cardiovascular research,
trends in cardiovascular research and subfields, citation impact and pat-
terns ofcollaboration between researchers in different countries.
7
METHODOLOGY
2.
2.1 Bibliometric analysis A number of assumptions underpin bibliometric techniques, and recent
reviews ofthe use ofbibliometrics in research evaluation have highlighted
its limitations.181'' It presupposes, firstly, that the output ofscientific research
is consistently represented by publications; secondly, that the number of
citations is an indicator of impact; thirdly, that accurate databases are
available.20
However, a survey of 24 studies in which bibliometric measures were
compared with other non-literature measures found a high correlation
between bibliometric statistics and other indices.21 A study by Narin in
1987 concluded that the results of bibliometrics are 'seldom counter-
intuitive'.14 In addition, a survey of academics' views of the quantitative
assessment of departmental research found cautious acceptance of
bibliometrics on the part ofacademic scientists, although the importance
ofconsulting with members ofthe research community under study was
emphasised.22 The study reported here addressed this last concern by the
extensive use of a group of cardiovascular research scientists and
administrators from each ofthe three funding bodies involved.*
Three key stages may be identified in bibliometric analysis:
• definitionofthesubjectfield (in thiscase, cardiovascularresearch)
• constructionofabibliographyconfinedtoappropriatetypesofpublication
• analysisofthe results
2.2 Defining the field: what The first stage in the assessment of research output of a particular
constitutes cardiovascular discipline is to set the boundaries ofthat discipline. This poses particular
research? difficulties with a field such as cardiovascular biology, which is
multidisciplinary and encompasses basic and clinical science.
Previous bibliometric studies have employed a number ofmethods offield
definition and each of these was considered for this study. One such
method is to define a field through a set of journals. The Science
Literature Indicators Database (SLID), derived from the Science Citation
Index produced by CHI Research Inc., is divided into research subfields
on this basis; in 1986, the cardiovascular subfield comprised publications
from international journals. However, use of a fixed number ofjournals
inevitably excludes a wide range ofnon-specialist journals which can carry
papers of relevance to cardiovascular biology. This could be a serious
omission, for example, in the case ofjournals such as the British Medical
Journal, the Lancetor Nature.
• Members ofthe Steering Group were Professor Andrew Henderson (University
ofWales, Cardiff), Dr Megan Davies and Dr Jane Rogers (Medical Research
Council, London), Professor Desmond Julian (British Heart Foundation,
London), Professor Philip A Poole-Wilson (National Heart and Lung Institute,
London) and Dr Laurence Smaje (the Wellcome Centre for Medical Science,
London).
8
