State of clinical neuroscience research in Saudi Arabia: where do we rank in the world?

J impact factor (IF) is a measure that reflects the average citation numbers of a recent publication in a journal. The h-index is a measure that indicates output and citation impact of articles published by a scientist. The wide acceptance of these 2 metrics signifies the importance of quantifying the scientific creditability of research and researchers. The IF and h-index can also be used to compare the scientific contribution of various countries to a particular specialty. The world ranking of universities had attracted substantial interest and it is also expected that the world ranking of medical specialty research will generate considerable appeal. Over the last 3 decades clinical neuroscience researchers from the Kingdom of Saudi Arabia (KSA) have contributed to the national and international literature. However, to date there has been no reports that compared the input of KSA researchers to the rest of the world. The objective of this study was to evaluate the state of clinical neuroscience research in KSA by determining its world ranking based on the quantity and citation impact of its research on the subject. In addition the study aimed to examine some of the features that may influence a country’s position among the top 50 in the world in clinical neuroscience research. SCImago Journal & Country Rank (SCR)1 is a portal that incorporates journal and country scientific indicators developed from Scopus database. The web site provides lists of country rankings based on 6 individual features: total documents, total citations, h-index, citable documents, citations per document, and self-citations. The findings vary according to the searched subject area, category, region and year. The SCR site was searched on twentieth August 2015 using the parameters “medicine” for subject area, “clinical neurology” for subject category, “1996-2014” for year and “all” for region. The site was also searched for “clinical neurology journals” and found to include 335 international journals that cover the range of clinical neuroscience specialties. The listed journals included Neuroscience (Riyadh) journal as well as 31 Neurosurgery journals including Pan Arab Journal of Neurosurgery. As a result it was considered appropriate to refer to “clinical neurology” in the SCR site as “clinical neuroscience” thereafter in this article. Using the site 3 separate top 50 world rankings based on total publications, total citations, and h-index in clinical neuroscience were obtained. These 3 parameters were chosen as they were considered appropriate indicators of the quantity and quality of research from any country. A correlation coefficient (R) was calculated between the 3 rankings. An adjusted top 50 ranking list was structured using mean values of the 3 rankings. When means were equal the country with higher total publications was ranked ahead. In addition to the 3 parameters the following country-related data were collected: population size from the worldometer web site,2 gross domestic2 product at purchasing power parity per capita (GDP/capita) from the International Monetary Fund database3 and the number of universities in the world top 500 from the Shanghai ranking web site.4 Furthermore, the number of clinical neuroscience journals listed in the SCR site for each country was determined. Using the median as a cut-off point, countries ranked 1-25 were compared to those ranked 26-50 utilizing the following parameters: population in million (≤23.5 versus >23.5), GDP/capita (≤ $31,500 versus >$31,500), number of universities in the world top 500 (≤ 3 versus >3) and the number of clinical neuroscience journals listed in the SCR site (1 versus >1). The findings were examined by a chi-squared test and significance was determined when p was less than 0.05. The Social Sciences Statistics site5 was used for the statistical analysis. Table 1 shows the adjusted ranking of the top 50 countries in the world in clinical neuroscience research during the period 1996-2014. The list integrates the 3 rankings: total publications, total citations, and h-index. The calculation of the mean was validated by the strongly positive correlation between the top 50 rankings based on total publications and total citations (R=0.9469), total publications and h-index (R=0.9215) and total citations and h-index (R=0.9908). According to the findings of this study, KSA is ranked fortieth in the world and fourth in the Middle East in clinical neuroscience research. The productivity of KSA researchers compared to the rest of the world was as follows: total publications 1,189 [range 1174,187 (median 37)], total citations 8,820 [range 04,406,449 (median 371)] and h-index 40 [range 0410 (median 11)]. The KSA countryrelated features compared to those ranked in the top 50 were; population in million: 29 [range 21394 (median 23.5)], GDP/capita: $52,000 [range $6,000$83,000 (median $31,500)], number of universities in world top 500: 4 [range 0164 (median 3)] and number of clinical neuroscience journals listed in the SCR site:2 [range 094 (median 1)]. Furthermore, the results showed that being ranked in the upper or the lower half of the top 50 in the world in clinical neuroscience research was not influenced by the country’s population being higher or equal and lower than 23.5 million (60% versus 40%) (p=0.1573). However, countries ranked 1-25 versus those ranked Brief report