Cataract research in India : A scientometric study of publications output , 2002-2011

Analyses the 1293 Indian publications in cataract research during 2002-2011, with a focus on contribution and citation impact of 15 most productive countries, India’s overall contribution, its growth, citation impact, the share of international collaborative papers, identifi cation of signifi cant countries in India’s international collaboration, different types of cataract research, analyses of research by subfi elds and different population age groups, productivity, and impact of leading Indian institutions and authors and pattern of communication of Indian output in most productive journals. The Scopus Citation Database has been used to retrieve the data for 10 years (2002-2011). Indian publications increased from 87 papers in 2002 to 195 papers in 2011, witnessing an annual average growth rate of 10.03%, registering an average citation impact per paper of 3.26 and international collaborative share of 21.58% during 2002-2011. Suggest that the government should encourage the decision makers and ophthalmologists and allied persons involved in ophthalmic services to make serious efforts in reducing the burden of cataract disease by increasing the R&D, strengthening of national and international collaboration and improve the existing training programs for ophthalmologic professionals.


INTRODUCTION
Cataract is the major cause of blindness and visual impairment present in more than half of all cases worldwide.In 1998, it was estimated that some 20 million people were blind due to cataract. [1]ataract is a clouding of the lens of the eye, due to the clumping of the protein elements of the lens or a discoloration that occurs with age, excessive sunlight exposure, diabetes, under nutrition, and other risk factors.The normal lens, clear and transparent, sits behind the colored iris and pupil and helps focus light on the retina, which converts the light images to electrical and chemical signals that are carried to the brain.A cataract blurs the image on the retina, producing a visual effect that is like looking through a window that is frosted or fogged with steam.Cataracts can affect one or both eyes.In addition to blurry vision and changes in color perception, symptoms can include glare and halo effects from lights and sun, failing night vision, and double vision.Cataract is detected by an eye examination that includes a visual acuity test and dilated eye exam. [2]taract is a common problem in many countries especially in developing countries.The problem of cataract in India has been profound, given the country's huge population.An above average incidence of cataract it is the leading cause of avoidable blindness (62.6%) in our country [3] in the early 1990s.It was estimated that more than 80% of blind people, or more than 10 million individuals, suffered from bilateral cataract, and another 10 million individuals had cataract in one eye in India.The prevalence of cataract increases with the aging population and in the female population, those who are illiterate and those residing in rural areas because exposure to smoke from indoor cooking represents a signifi cant risk factor. [4]nternational Journal of Medicine and Public Health | Oct-Dec 2014 | Vol 4 | Issue 4 sponsored scheme to address the problem.In 1978, the National Program accepted assistance from (The Danish International Development Assistance Organization) for the nationwide expansion of infrastructure (equipment and mobile units) and training of paramedical ophthalmic assistants.In 1994, the World Bank assisted Cataract Blindness Control Program begun in seven states in India where the need was the most concentrated: Andhra Pradesh, Madhya Pradesh, Maharashtra, Orissa, Rajasthan, Tamil Nadu, and Uttar Pradesh with the objective to improve the quality of cataract surgery and lessen the prevalence of blindness by reducing the backlog of cataract blindness in the participating states.Due to these efforts, the overall population prevalence of cataract blindness was declined by 26% from 1.5% at baseline to 0.13%, during this program period. [5]ly few scientometric studies on cataract research were published in the past.Gupta et al., [6] analyzed the global publications in cataract research during 2002-2011 on several parameters including contribution and citation impact of top 15 most productive countries, different types of cataract research, research output by different population age groups, subject-wise break-up of research output, relatedness of various diseases to cataract research, research contribution and impact of top 15 institutions and authors and productivity of the top 20 journals.Tsai et al., [7] investigated the quantity and quality of world research output (8186 papers) in cataract research using SCI database during 1991-2005 focusing on growth, productivity, the authorship pattern, international collaboration and subject trends using keywords.Fan and McGhee [8] identifi ed the most-published authors on the topics of "cataract" and laser in situ keratomileusis ("LASIK"), the journals in which they publish, and the citation patterns of the most-cited articles by these authors over a 5 years publication period (2000-2004).USA and Australia together were the source of more than half of the most-published authors on cataract and LASIK and the majority of articles published by 30 most prolifi c authors were published in only 10 journals.Wu et al., [9] explored the distribution of research articles (45868) on cataract, as published in PubMed database, from 1913 to 2010.The cataract literature was primarily in English (34655-75.6%).Around 10299 papers, 23% were retrieved in 22 journals on ophthalmology (SCI-indexed).Chinese cataract literatures in PubMed appeared in 1946 and increased obviously since 1961.Chinese publications (732) were ranked at 7 th rank with 1.59% share.
Among the studies conducted on country distribution of ophthalmology and visual science literature include: Davis et al., [10] studied Australia's contribution to vision science domain literature during 1991-1995, using ISI's SCI, SSCI, and AHCI databases.Zou, Wu et al. [11] analyzed 961 ophthalmology, optometry, and visual science publications of China, using SCI database during 2000-2007.Kumaragurupari et al., [12] analyzed 2163 publications by Indian ophthalmologists and vision researchers during 2001-2006, with a view access their productivity, analyze trends in journal choice, publication types, and research funding and collaborative research.
Publications resulting from international collaborations increased from 3% in 2001% to 8% in 2006.

Objectives
The main objective of this study is to analyze the cataract research output in India during 2002-2011.The study has the following objectives: 1.To study the contribution and citation impact of top 15 most productive countries, 2. To study the India's overall contribution, its growth pattern and citation impact, 3. To study the share of international collaboration in India's overall research output, contribution of leading countries, and identifi cation of leading foreign collaborating partners; 4. To study Indian contribution and impact of different types of cataract research, cataract research by sub-fi elds and cataract research output by different age groups and keywords, 5. To study the productivity and impact of leading Indian institutions and authors; and 6.To study the pattern of communication of Indian output in most productive journals.

Global publications output and citation impact
The global publication share of the top 15 most productive countries in cataract research varied from 1.29% to 24.08% during 2002-2011.United States tops the list, with a share of 24.08%, followed by United Kingdom and China (9.66% and 8.16% share, 2 nd to 3 rd rank) and Japan and Germany (6.11% and 5.71% share, 4 th to 5 th rank).India and Australia ranked at 6 th to 7 th positions (their global publications share of 4.78% and 3.56%).Canada, Italy, France, Turkey, Spain, Brazil, Netherlands, and Austria ranked at 8 th to 15 th positions (their global publications share ranging from 1.29% to 2.91%) [

Different types of cataract research
Under different type of cataract research (classifi ed by etiology), the maximum Indian publication output (282) during 2002-2011 was on congenital cataract with 21.81% publication share, followed by cataract associated with primary ocular diseases (272

Cataract research output in context of different subjects
India's publication output in cataract research during 2001-2011 has been published in the context of 5 subjects (as refl ected in database classifi cation), with highest publications output coming from medicine (1104 papers and 85.38% publications share), followed by neurosciences (128 papers and 9.90% publications share), pharmacology, toxicology and pharmaceutics (108 papers and 8.35% publications share), biochemistry, genetics and molecular biology (87 papers and 6.73% publications share), and agricultural and biological Sciences (23 papers and 1.78% publications share) [Table 5].Among these subjects, biochemistry, genetics, and microbiology scored the highest citation impact (4.67 citations per paper), followed by agricultural and biological sciences (4.04), medicine (3.39), neurosciences (2.51) and pharmacology, toxicology, and pharmaceutics (2.12) [Table 6].

Cataract research by population age groups
The maximum focus of India cataract research in terms of research output during 2002-2011 was on adults (536 papers and 41.45% share), followed by middle aged persons (381 papers and 29.47% share), child (183 papers and 14.15% share), and adolescents (155 papers and 11.99% share).Similarly, the focus on males (689 papers and 53.29% share) was higher than female (594 papers and 45.94% share).

Research Profi le of most productive Indian organizations in cataract research
The       In spite of cataract being the main cause of avoidable blindness (62.6%),India has published only 1293 papers on cataract research during the last 10 years.It means the research efforts need to be strengthened quiet substantially by way of investment in R&D.Both research output and quality of research should be increased and strengthened, and international collaborative research may further be widened to learn from the experiences of other countries.Besides this, there is a need to encourage the decision makers, managers, and most importantly ophthalmologists, ophthalmic personnel, paramedics, and all other persons involved in ophthalmic surgical services to make serious efforts in reducing the burden of cataract disease.To eliminate the main causes of avoidable blindness, that is, cataract appropriate national planning is necessary. In addition to this, Government should enhance the quality of care, technical and operational norms, use of modern surgical techniques, expand the coverage of rural and isolated population through massive communications, and develop human resources for an eyecare delivery.Efforts should also be made to increase the training programs for ophthalmologic professionals, sharing the results of research and monitoring to motivate improvements.

Table 1
].The developed countries showing increase in their publications share were Spain by 0.7%, followed by Turkey (0.42%), Canada (0.37%), and Italy (0.26%), in contrast to decrease in USA by 3.71%, U.K.(1.53%),Japan (1.08%),Germany (0.75%), France (0.44%), Austria (0.33%), Netherlands (0.17%), and Australia (0.12%) from 2002-2006 to 2007-2011.All developing countries have shown rise in their publications share in cataract research: China by 6.54%, followed by India (0.85%) and Brazil (0.09%) from 2002-2006 to 2007-2011 [Table 1].India ranks at 6 th position among the top 15 most productive countries in cataract research with its global publications share of 4.78% during 2002-2011.China and Brazil ranked at 3 rd and 13 th positions, with global publications share of 8.16% and 1.99%, respectively, during 2002-2011.India's global publications share increased from 4.31% to 5.16% from 2002-2006 to 2007-2011.China and Brazil's global publications share increased from 4.58% to 11.12% and 1.94% to 2.03% from 2002-2006 to 2007-2011 [Table 1].India's contribution in cataract research has increased from 87 papers in 2002 to 195 papers in 2011, witnessing an annual average growth rate of 10.03%.Its cumulative publications output has increased from 528 papers during 2002-2006 to 765 papers during 2007-2011, witnessing a growth rate of 44.89%.The average citation impact per paper registered by India's cataract research during 2002-2011 was 3.26, which has decreased from 4.07 during 2002-2006 to 2.71 during 2007-2011.India has contributed 21.58% international collaborative papers share in cataract research during 2002-2011, which has increased from 20.08% during 2002-2006 to 22.61% during 2007-2011 [Table 2].In all 45 countries participated in international collaboration with India in cataract research during 2002-2011, of which contribution of top 12 countries is listed in Table3.The largest contribution to international collaborative papers of India in cataract

Table 2 : India's publications output and international collaborative publications output in cataract research, 2002-2011
TP = Total papers, TC = Total citations, ACPP = Average citation per paper, ICP = International collaborative papers

Table 3 : Major collaborative partners of India in cataract research, 2002-2011
ICP = International collaborative papers, *Total collaborating papers of India, In all collaborating papers of India, there are one or more foreign collaborating countries.As a result, the combined output of 12 foreign collaborating countries listed above in Indian international collaborative output will be more than its total international collaborative papers International Journal of Medicine and Public Health | Oct-Dec 2014 | Vol 4 | Issue 4 Indian organizations have registered higher citation impact per paper than the group average of 4.04 during 2002-2011: (i) National Institute of Nutrition, Hyderabad (9.42), H V Desai Eye Hospital, Pune (7.67), Aravind Medical Research Foundation, Madurai (7.13), Aravind Eye-Care System, Lions Aravind Institute of Community Ophthalmology, Madurai (5.30), Aravind Eye Hospital, Pondicherry (4.87), and Iladevi Cataract Intraocular Lens Research, Ahmedabad

Table 6 : Subject-wise break-up of Indian publications in cataract research during 2002-2011
Total of India in cataract research.There is some overlapping of literature under diff erent sub-fi elds.As a result, the combined output of India under 8 sub-fi elds will be more than its total research output, TP = Total papers, TC = Total citations, ACPP = Average citation per paper *

Table 4 : Foreign collaborating centers with India along with their output in cataract research, 2002-2011 Name of foreign collaborating organization Research output
Bethesda, USA International Journal of Medicine and Public Health | Oct-Dec 2014 | Vol 4 | Issue 4 share).Among the sub-fi eld-wise distributions of Indian cataract research during 2002-2011, the largest contribution (85.38% share) comes from medicine and biochemistry, genetics and microbiology had scored the highest impact (4.67 citations per paper).The top 15 most productive Indian institutions involved in cataract research have together contributed 57.62% share in the cumulative Indian publications output, with an average of 49.67 papers per institution.The average citation per paper and h-index registered by the total papers of these 15 institutions was 4.04 and 11.4 during 2002-2011.The 15 most productive Indian authors together contributed 34.73% share in the cumulative Indian publications output during 2002-2011, with an average of 29.93 papers per author.The average citation per paper and h-index registered by the total papers of these 15 authors was 4.09 and 9.33 during 2002-2011.The 15 most productive journals publishing Indian research papers in cataract research together accounts for 41.22% share of the total Indian output during 2002-2011, which increased from 40.72% during 2002-2006 to 41.57% during 2007-2011.
Source of Support: Nil, Confl ict of Interest: None declared.