GENERAL ARTICLES
CURRENT SCIENCE, VOL. 110, NO. 7, 10 APRIL 2016 1178
Nirmal Singh and Dhiraj Kumar are in the Guru An
gad Dev Veterinary
and Animal Sciences University, Ludhiana 141
004, India; Tarvinder
Singh Handa is in the Indian Institute of Technology Ropar,
Rupnagar 140 001, India; Gurpreet Singh is in the Goswami
Ganesh
Dutta S.D. College, Chandigarh 160 031, India.
*For correspondence. (e-mail: nirmal02@yahoo.co.in)
Mapping of breast cancer research in India:
a bibliometric analysis
Nirmal Singh*, Tarvinder Singh Handa, Dhiraj Kumar and Gurpreet Singh
This study presents a bibliometric analysis of the scholastic output on breast cancer in India. The
purpose is to provide an overview of the research activities in the country on the subject during the
last ten years, exploring different aspects of scientific literature. Data on 3529 items, including
2945 articles and 584 reviews published during 1 January 2005 to 31 December 2014 were col-
lected using Scopus. An advanced search was conducted in the database. The search results were
filtered for English language, journals, India and the period under study. Lotka’s law was applied
to assess the author productivity and Bradford’s law of scattering was used to ascertain the distri-
bution pattern of articles in journals. Most (about 96%) contributions were found to be an outcome
of collaborative authorship. Around 19.05% of the papers had collaboration of four authors and
16.53% appeared due to collective efforts of three authors each. Trend of an increasing number of
articles published over the period has been observed. Author productivity did not fit the Lotka’s law
with a value of n = 2. The distribution of articles in journals was found acceptable to the Brad-
ford’s law of scattering.
Keywords: Bibliometric analysis, breast cancer, collaborative authorship, research activities.
CANCER is one of the major health concerns worldwide.
The year 2012 witnessed 14.1 million new cases of
cancer and global mortality of 8.2 million due to the
noxious disease
1
. Cancer of the lungs, colorectal and
stomach cancer and breast cancer accounted for more
than 40% of all cases diagnosed globally. While cancer of
the lungs occurred more frequently in men, breast cancer
was the most commonly diagnosed cancer in women,
constituting 25.2% of all new cases
2
.
Cancer is one of the top 10 causes of death in India
3
.
Breast cancer accounts for 22.2% of all new cancer dia-
gnoses and 17.2% of all cancer deaths among women in
the country
4
. In 2012, 144,937 women were newly de-
tected with breast cancer and 70,218 died due to this fatal
disease
5
. The rate of increase in breast cancer in the coun-
try ‘is so rampant, that if we do not act now, we are in for
a major shock in the next twenty years’
6
. More alarming
is a considerable shift over the last few decades in the age
of young women showing development of breast cancer
7
.
While the peak occurrence of breast cancer in the United
States and other European countries in women is in their
sixties
8
, almost 48% of the patients in India are below 50,
with an increasing number of patients in the age group
between 25 and 40 years
9
.
The world age-standardized rate (ASR) of incidences
of breast cancer is 43.1 per 100,000 women and the age-
standardized breast cancer death rate is 12.9 per 100,000
females. Compared to this, the ASR of incidences of
breast cancer in India is 25.76 per 100,000 women. How-
ever, in proportion to the incidence rate, the ASR of
mortality in the country is much higher than that in the
developed countries, taking 12.73 lives per 100,000
women
10
. Hence, in India, on an average, for every two
women newly diagnosed with breast cancer, one is dying
from this disease. It is estimated that the incidence of new
cases of breast cancer in India will rise up to 200,000 per
year by 2030 (ref. 11).
Women have a crucial role in the social, economic and
cultural development of society. In male-dominated
India, the health and care of women is a critical issue.
The absence of typical female advantage in life expec-
tancy suggests the systematic problems in the health of
women in the nation
12
. Women are mainly exposed to in-
door pollutants at home and in the workplace, and there
are evidences that they are more vulnerable than men to
various chemicals
13
. Improper nutritional intake
14
, over-
weight and obesity in early adulthood
15
also account for
this fatal disease. For sustainable well-being of women, it
is essential that ‘strategic interventions are made at criti-
cal stages’
16
. Research, evidence and information are basic
to sound health policies
17
. There is significant positive
GENERAL ARTICLES
CURRENT SCIENCE, VOL. 110, NO. 7, 10 APRIL 2016 1179
correlation between improvement in the survival rate of
patients and research output
18
. Therefore, quantitative
assessment of the scholarly research output of India on
breast cancer is pertinent to map out the growth trends
and its future perspectives, as this can have a significant
bearing on the future research and policies to tackle the
disease in gender-disturbed nation. Bibliometric analysis
is a statistical support device to map out and generate
different types of information, and knowledge handling
and management indicators
19
.
Objectives
The present study is aimed at assessing (i) the year-wise
distribution of papers, (ii) authorship pattern, (iii) author
productivity and productive authors, (iv) institutional
contributions, (v) fitness of distribution of papers to
Bradford’s law of scattering, and (vi) the core journals
publishing papers on breast cancer.
Methodology
For bibliometric analysis, data regarding papers on breast
cancer were collected using Scopus in July 2015, for the
period 1 January 2005 to 31 December 2014. Scopus is
the largest abstract and citation database of peer-reviewed
literature, including scientific journals, books and confer-
ence proceedings in the disciplines of science, techno-
logy, medicine, social sciences, arts and humanities. To
access data for the present study, Scopus was searched as
follows:
An advanced search was conducted using ‘breast
cancer’ and alternative search terms, i.e. ‘breast carci-
noma’, ‘neoplasm of breast’, ‘tumor of breast’,
‘tumour of breast’, ‘mammary cancer’, ‘ductal carci-
noma’ and ‘invasive carcinoma’.
The search was restricted to the occurrence of search
terms in the title, abstract and keywords of the
articles.
Boolean operator ‘OR’ was applied to the above
search terms to produce an exhaustive number of
results.
The search results were filtered to English language,
journals, India and restricted to the period of ten years
under study, i.e. 2005–2014.
The search was further filtered by subject areas to
cover articles in medicine, biochemistry, pharmacology,
nursing, health science, multidisciplinary and immu-
nology.
The search results provided 3529 records covering
2945 articles and 584 reviews for the period under
study on the given search terms.
The data were downloaded in Excel format and
analysed.
Data analysis was performed using frequencies and
percentages of publications. Besides, Lotka’s law was
applied to assess the author productivity and Brad-
ford’s law of scattering was used to ascertain distribu-
tion pattern of articles.
Analysis and discussion
Year-wise distribution of papers
During the period 2005–2014, a total 3529 papers were
published on breast cancer by authors with institutional
affiliation in India, either individually or in national/
international collaboration. The trend of growing number
of publications over the period can be observed in Table
1, indicating that with the increasing burden of breast
cancer in the country, research on the issue has also
increased. This supports the study of Kotepui et al.
20
revealing the trend of growing number of publications
from Asian countries. It took seven years (2005–2011) to
produce 48.54% (1713 papers) of the total contributions
during the period under study, while the rest 51.46% was
published during the last 3 years (2012–2014) only.
The year 2014 produced more publications than the first
four years under study, viz. 2005–2008. On an average,
Table 1. Year-wise distribution of papers
Cumulative
Year No. of papers Percentage frequency
2005 119 03.38 119
2006 168 04.77 287
2007 176 04.99 463
2008 182 05.16 645
2009 258 07.31 903
2010 365 10.34 1268
2011 445 12.60 1713
2012 534 15.13 2247
2013 608 17.22 2855
2014 674 19.10 3529
Total 3529 100.00
Table 2. Authorship pattern
No. of authors No. of papers Percentage
1 135 03.82
2 449 12.72
3 583 16.53
4 672 19.05
5 524 14.85
6 396 11.22
7 229 06.49
8 159 04.50
9 120 03.40
10 71 02.01
>10 191 05.41
Total 3529 100.00
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CURRENT SCIENCE, VOL. 110, NO. 7, 10 APRIL 2016 1180
scientific output on the subject increased by nearly 19%
per annum.
Authorship pattern
The number of authors contributing to each publication
varied from 1 to 295. A large majority of papers had been
written in collaboration, with the exception of only 135
(03.82%) single-authored papers (Table 2), corroborating
the findings of Minas et al.
21
and Sridevi
22
. Interestingly,
05.41% of the papers resulted from collaboration of more
than 10 authors, including 4 articles having more than
100 authors each. Also, 3529 articles and reviews were
contributed by 18,544 authors, each publication having
around 5 authors, on an average. The degree of collabora-
tion of authorship was calculated using the formula given
by Subramanyam
23
3394
0.9617,
3394 135
Nm
C
Nm Ns
where C is the degree of collaboration, Nm the number of
multi-authored works, and Ns is the number of single-
authored works.
Author productivity
Author productivity was assessed considering the first
author of each article (Table 3). A total of 2521 authors
had made 3529 contributions. Majority of authors
(80.00%) contributed only one paper, followed by
11.79% authors contributing 2 publications each. Lotka’s
law was applied to calculate the number of expected
authors for a given number of publications. Considering
the fact that 2017 authors have produced only 1 paper
each, the value of n can easily be derived. Putting the value
of n as 2, the results shown in Table 3 were obtained.
Table 3 shows that there are only a few productive
authors, a large majority contributing to breast cancer
occasionally. In contrast to the study of Parta and Bhatta-
charya
24
, the present results suggest that in this case the
author distribution does not obey Lotka’s law. The differ-
ence between the number of observed authors and
expected authors was considerably wider.
Prolific authors
The most prolific authors on the subject of breast cancer
have been identified and ranked (Table 4). There were 12
authors each publishing more than 20 papers. The author
with the highest contribution in terms of the number of
papers on breast cancer is Sachdanandam contributing 30
publications, followed by Parshad and Konwar (26 each).
Saxena and Sarin contributed 25 and 24 papers respec-
tively. Of the total 18,544 authors, 159 Indian authors
made a contribution to 51.40% of the total 3529 publica-
tions, whereas the remaining majority to the rest of the
48.60% contributions.
Core journals in the subject
The total 3529 papers analysed in this study appeared in
972 journals from various publishers and geographical
locations. Table 5 shows the most productive journals on
breast cancer. Around 27.76% (980) of the total publica-
tions under the study appeared only in 25 journals, which
may be considered as core journals (Table 5).
The impact factor (IF) is a widely accepted quality
determinant for journals, reflecting the average number of
citations to recent articles published in a journal. Higher
the IF, more important the journal is considered to
be. However, 10 of the 25 core journals publishing the
highest number of articles on breast cancer did not have
an IF. Eight of these 10 journals without IF, are being
Table 3. Author productivity
No. of authors No. of authors
No. of papers observed expected
1 2017 (80.00) 2017 (63.22)
2 297 (11.79) 504 (15.80)
3 105 (04.17) 224 (07.02)
4 45 (01.79) 126 (03.94)
5 21 (00.84) 81 (02.54)
6 11 (00.44) 56 (01.76)
7 8 (00.31) 41 (01.29)
8 3 (00.11) 32 (01.00)
9 3 (00.11) 25 (00.79)
10 1 (00.04) 20 (00.62)
11 4 (00.16) 17 (00.54)
12 2 (00.08) 14 (00.44)
13 1 (00.04) 12 (00.38)
14 1 (00.04) 10 (00.31)
19 1 (00.04) 6 (00.19)
21 1 (00.04) 5 (00.16)
Total 2521 (100.00) 3190 (100.00)
Figures in parenthesis represent percentage.
Table 4. Prolific authors
Author No. of papers Percentage
Sachdanandam, P. 30 00.85
Parshad, R. 26 00.73
Konwar, R. 26 00.73
Saxena, S. 25 00.70
Sarin, R. 24 00.68
Ralhan, R. 23 00.65
Kamal, A. 23 00.65
Kumar, R. 22 00.62
Munshi, A. 22 00.62
Gupta, S. 22 00.62
Shanthi, P. 22 00.62
Badwe, R.A. 22 00.62
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CURRENT SCIENCE, VOL. 110, NO. 7, 10 APRIL 2016 1181
Table 5. Core journals in the subject
No. of Impact
Journal Rank papers Percentage Country factor (2014)
Asian Pacific Journal of Cancer Prevention 1 104 02.94 Korea 2.514
Journal of Cancer Research and Therapeutics 2 79 02.23 India 0.791
European Journal of Medicinal Chemistry 3 61 01.72 Italy 3.447
PLoS ONE 4 57 01.61 USA 3.234
Indian Journal of Cancer 5 53 01.50 India 0.802
International Journal of Pharma and Bio Sciences 6 50 01.41 India Nil
Bioorganic and Medicinal Chemistry Letters 7 49 01.38 UK Nil
Indian Journal of Surgical Oncology 8 48 01.36 India Nil
Journal of Clinical and Diagnostic Research 8 48 01.36 India Nil
Indian Journal of Pathology and Microbiology 9 47 01.33 India 0.466
International Journal of Pharmacy and Pharmaceutical Sciences 10 46 01.30 India Nil
Medicinal Chemistry Research 11 39 01.10 USA 1.402
Indian Journal of Medical Research 12 29 00.82 India 1.396
International Journal of Pharmaceutical Sciences Review and Research 13 27 00.76 India Nil
Journal of the Indian Medical Association 13 27 00.76 India Nil
Research Journal of Pharmaceutical, Biological and Chemical Sciences 14 26 00.73 India Nil
Diagnostic Cytopathology 15 24 00.68 USA 1.121
Bioorganic and Medicinal Chemistry 16 23 00.65 UK Nil
Journal of Cytology 16 23 00.65 India 0.374
Breast Cancer Research and Treatment 17 22 00.62 USA 3.940
Molecular and Cellular Biochemistry 18 21 00.59 The Netherlands 2.393
Indian Journal of Surgery 19 20 00.56 India 0.260
Tumor Biology 19 20 00.56 The Netherlands 3.611
Indian Journal of Medical and Paediatric Oncology 20 19 00.53 India Nil
Cancer Research 21 18 00.51 USA 9.329
Table 6. Zones of journals
No. of Percentage No. of
Zone journals of journals papers k
Core Zone 25 02.58 980 –
Zone 1 141 14.50 1161 5.700
Zone 2 806 82.92 1388 5.699
Total 972 100 3529
published from India. This corroborates the findings of
Patra and Bhattacharya
24
, that the Indian cancer research
articles are not published in high-impact journals.
Bradford’s law of scattering
Bradford’s law of scattering is used to describe the distri-
bution of the literature on a particular subject in jour-
nals
25
. The law working on mathematical means is based
on the principle of centric productivity zones, demon-
strating that there are diminishing returns when the litera-
ture is published exhaustively. According to the law,
journals can be divided into different zones containing
the same number of articles. For example, the core zone
contains one-third of the total articles; similarly zone 1
contains the same number of articles, but a greater num-
ber of journals, and zone 2 contains the same number of
articles, but still greater number of journals, and so on.
This increase in the number of journals from one zone to
the next is according to the expression 1
:
n
:
n
2
. The law
helps to distinguish the groups of journals dedicated more
specifically to the subject of interest. The number of
journals in each zone can be calculated from Bradford’s
multiplier constant k. In this study, k has been arrived at
using the mathematical formulations of Egghe
26
, and
Egghe and Rousseau
27
as given below
k = (e
Ym)
1/ p
,
where
is Euler’s number having a value 0.57772, Ym is
the number of articles published in the top-ranked journals
and p is the Bradford group or number of zones, i.e. p = 3.
Therefore,
k = (1.781 104)
1/3
= 5.70.
The different Bradford groups can be calculated using k.
The core zone r
0
can be defined as
0
( 1)
,
( 1)
p
T k
r
k
where T represents the total number of journals in the
study.
Thus,
0
3
972(5.70 1) 4568.4
24.81.
184.193
(5.70 1)
r
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CURRENT SCIENCE, VOL. 110, NO. 7, 10 APRIL 2016 1182
Table 7. Institutional contribution
Institution No. of papers Percentage
Tata Memorial Hospital 175 04.95
All India Institute of Medical Sciences 169 04.78
University of Madras 90 02.55
Indian Institute of Chemical Technology 81 02.29
Postgraduate Institute of Medical Education and Research 77 02.18
Central Drug Research Institute 63 01.78
National Institute of Pharmaceutical Education and Research 54 01.53
Sanjay Gandhi Postgraduate Institute of Medical Sciences 47 01.33
Chittaranjan National Cancer Institute 46 01.30
National Centre for Cell Science 42 01.19
Indian Institute of Science 41 01.16
Nizam's Institute of Medical Sciences 40 01.13
Banaras Hindu University Institute of Medical Sciences 40 01.13
Osmania University 39 01.10
Institute Rotary Cancer Hospital 38 01.07
Annamalai University 37 01.04
Regional Cancer Centre 36 01.02
Vardhman Mahavir Medical College and Safdarjung Hospital 36 01.02
Manipal University 36 01.02
Jadavpur University 36 01.02
Table 8. Collaboration with other nations
Country No. of papers Percentage
India 3529 100.00
United States of America 417 11.81
Germany 57 01.61
United Kingdom 56 01.58
Canada 48 01.36
France 45 01.27
Saudi Arabia 43 01.21
Australia 41 01.16
Singapore 32 00.90
South Korea 30 00.85
Different Bradford zones have been obtained using the
values of k and r
0
Core zone r
0
= r
0
1 = 24.81,
First zone r
1
= r
0
k = 24.81 5.70 = 141.42,
Second zone r
2
= r
0
k
2
= 24.81 5.70
2
= 806.08.
The above theoretical distribution according to Brad-
ford’s law enables one to examine the exact fit of the law
to the distribution of articles. Using this distribution, the
number of journals in each zone has been arrived at
Table 6. Using the distribution of journals in Table 6, k is
5.700 and 5.699 for zone 1 and zone 2 respectively. This
value of k is similar to that calculated using the
formula k = (e
Ym)
1/p
. This makes it clear that data col-
lected for the present study fit into the three zones of
Bradford’s law of scattering, i.e. 1
:
k
:
k
2
or 1
:
n
:
n
2
.
Institutional contribution
Table 7 gives the top 20 institutions in terms of their con-
tribution to the number of papers on breast cancer. It can
be observed that medical institutions and hospitals make
a greater contribution to the literature on breast cancer
than universities, contrary to the findings of Ortiz et al.
28
.
Collaboration with other nations
Table 8 lists the major nations along with the number of
papers in which Indian authors had collaborated with the
authors from other nations. Indian authors contributed
417 publications in collaboration with authors from the
United States. India has collaboration in 57 papers with
Germany, followed by 56 contributions with the United
Kingdom. Canada, France, Saudi Arabia, Australia, Singa-
pore and South Korea are the other nations with which
Indian authors have contributed 30 or more papers.
Conclusion
Research and scientific activities on breast cancer involve
a high degree of collaboration, not limiting to the geo-
graphical boundaries. The present study shows that
11.81% of the papers are contributed by Indian authors in
collaboration with authors from the United States. Simi-
larly, countries such as Germany, United Kingdom, Can-
ada, France, etc. collaborate with authors from India. A
growing trend of publications in the subject is observed.
In comparison to 119 papers published in 2005, the num-
ber of contributions has increased by 466% during 2014.
Majority of the authors contribute to the subject occa-
sionally. However, author productivity does not fit to
Lotka’s law, as the observed and expected values vary
significantly. The distribution of papers obeys the Brad-
ford’s law of scattering identifying 25 core journals. The