Research output from India's Siddha system of medicine during 1972-2019: Bibliometric analysis points need to focus on quantity and quality

The Siddha system of medicine (SSM) is one of the Indian Systems of Medicine (ISM). In recent times, it has received adequate support from the Indian Ministry of Ayush. Like many such indigenous systems of medicine globally, the SSM is based on its own theoretical principles, philosophy, and methods of practice. Nevertheless, SSM conducts and needs basic and applied research using scientific methods. Such research is evidenced by research publications. In the absence of a review, we did a bibliometric analysis of research publications from SSM for the period of 1972-2019. We used the term "Siddha" to retrieve the data from the PubMed database. We retrieved data from the National AYUSH research portal and homepages of institutions mandated to do research in SSM. We abstracted bibliometric information and used Epi info (Version 7.2) for analysis. We described the trends and key characteristics. Of a total of 2009 retrieved articles, we included 1457 (73%) for analysis. Between 1972 and 2001, the median number of publications per year was three (range: 0-13). Beyond 2012, the publications increased exponentially with an annual growth of 23%. The maximum number of publications ( = 224) was in 2019. Among 43 countries that produced the papers, India topped it (88%). Of 1457, 1.7% ( = 25) of publications from Siddha institutions were indexed in PubMed. A bibliometric review of research output from SSM suggests that the publications have increased in the last two decades. The review recommends improving research output from SSM in terms of quantity and quality.