A Bibliometric Analysis of Scientific Production on Second-Generation Anti-Psychotic Drugs in Malaysia

Abstract

Objective: We carried out a bibliometric study on the scientific papers related to second-generation antipsychotic drugs (SGAs) in Malaysia.

Methods: With the SCOPUS database, we selected those documents made in Malaysia whose title included descriptors related to SGAs. We applied bibliometric indicators of production and dispersion, as Price's law and Bradford's law, respectively. We also calculated the participation index of the different countries. The bibliometric data were also been correlated with some social and health data from Malaysia (total per capita expenditure on health and gross domestic expenditure on R&D).

Results: We found 105 original documents published between 2004 and 2016. Our results fulfilled Price's law, with scientific production on SGAs showing exponential growth (r = 0.401, vs. r = 0.260 after linear adjustment). The drugs most studied are olanzapine (9 documents), clozapine (7), and risperidone (7). Division into Bradford zones yields a nucleus occupied by the Medical Journal of Malaysia, Singapore Medical Journal, Australian and New Zealand Journal of Psychiatry, and Pharmacogenomics. Totally, 63 different journals were used, but only one in the top four journals had an impact factor being greater than 3.

Conclusion: The publications on SGAs in Malaysia have undergone exponential growth, without evidence a saturation point.

Keywords: Malaysia; atypical anti-psychotics; bibliometrics; bipolar disorder; schizophrenia; second-generation anti-psychotics.

Figure 1

Growth of scientific production on SGAs in Malaysia. A linear adjustment of the data was carried out, and a fitting to an exponential curve, in order to check whether production follows Price’s law of exponential growth Linear adjustment: y = 0.719x–1438.7 (r = 0.027) Exponential adjustment: y = 2E–11e^0.135x (r = 0.421)

Figure 2

Temporal evolution of number of documents on second-generation anti-psychotic drugs (13 years)

Figure 3

Number of papers on second-generation anti-psychotic drugs (2004–2016)

Figure 4

Evolution of documents on three more relevant second-generation anti-psychotic drugs

Figure 5

Evolution of the number of documents every three-years period

Figure 6

Cumulative growth by three-year periods of scientific production on total productivity in Psychiatry (and Mental Health) and Neurology area, and SGAs in Malaysia. Data from each three-year period refer to evolution over the previous period. The period of reference is 2004–2006. Data are expressed in percentages AADs: atypical anti-psychotic drugs, or SGA: second-generation antipsychotics

Figure 7

Relationship between production of scientific literature on SGAs and total production in the field of Psychiatry and Neurology in the world’s 10 most productive countries and Malaysia for the period 1996–2015 PI: participation index; SGAs: second-generation anti-psychotics

Figure 8

GDP per capita and relationship between production of scientific literature on SGAs and the total expenditure on health on gross domestic product and per capita in Int$, in the world’s 10 most productive countries in psychiatry and neurology and Malaysia *World Bank data (2014); **World Health Organization data (2015); GDP: gross domestic product; PI: participation index