en Epidemiology Epidemiology Original Research Original Research <p dir="ltr" style="text-align: justify"><strong>Background: </strong>Investment in science is vital for the development and well-being of societies. This study aims to assess the scientific productivity of countries by quantifying their publication of systematic reviews taking the gross national income per capita (GNIPC) into account.</p> <p dir="ltr" style="text-align: justify"><strong>Methods</strong>: Medline and ISI Web of Science were searched for systematic reviews published between 1st January 2006 and 31st December 2010. The productivity of each country was quantified by exploring the authors’ affiliation. The GNIPC was used according to the World Bank Report. Concentration index (CI) was calculated as the index of inequality. </p> <p dir="ltr" style="text-align: justify"><strong>Results</strong>: CI of percentage of systematic reviews as a function of percentage of countries ranked by GNIPC was 0.82 which indicates inequality in production of systematic reviews in pro rich countries. Countries with high income produced 206.23 times more systematic reviews than low income countries, while this ratio for lower middle and upper middle countries was 9.67 and 12.97, respectively. The highest concentration index was observed in clinical sciences (0.76) and the lowest in public health (0.61).</p> <p dir="ltr" style="text-align: justify"><strong>Conclusion</strong>: This study demonstrates a significant gap between industrialized and non-industrialized countries in the production of systematic reviews. Addressing this gap needs tremendous national and international efforts.</p> <p></p> Systematic review, Scientific productivity, Gross national income, Inequality. 1270 1277 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-1-939&slc_lang=en&sid=1 Arsia Jamali ajamali@student.tums.ac.ir 200319475328460020216 200319475328460020216 No Scientific Research center, Tehran University of Medical Sciences, & Exceptional Talents Development Center, Tehran University of Medical Sciences, Tehran, Iran. Saharnaz Nedjat nejatsan@tums.ac.ir 200319475328460020217 200319475328460020217 Yes Epidemiology and Biostatistics Department, School of Public Health, Tehran University of Medical Sciences, & Knowledge Utilization Research Center, Tehran University of Medical Sciences, Tehran, Iran. Kazem Heidari k_heydari1515@yahoo.com 200319475328460020218 200319475328460020218 No Epidemiology and Biostatistics Department, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Raika Jamali jamalira@tums.ac.ir 200319475328460020219 200319475328460020219 No Students’ Scientific Research center, Tehran University of Medical Sciences, Tehran, Iran. Kiana Hassanpour kiana_h87@yahoo.com 200319475328460020220 200319475328460020220 No Students’ Scientific Research center, Tehran University of Medical Sciences, & Exceptional Talents Development Center, Tehran University of Medical Sciences, Tehran, Iran. Sima Nedjat nejat_s@farabi.tums.ac.ir 200319475328460020221 200319475328460020221 No Knowledge Utilization Research Center, Tehran University of Medical Sciences, & University of Social Welfare and Rehabilitation, Tehran, Iran. Pasha Anvari panvari@student.tums.ac.ir 200319475328460020222 200319475328460020222 No Students’ Scientific Research center, Tehran University of Medical Sciences, & Exceptional Talents Development Center, Tehran University of Medical Sciences, Tehran, Iran. Reza Majdzadeh rezamajd@tums.ac.ir 200319475328460020223 200319475328460020223 No Epidemiology and Biostatistics Department, School of Public Health, Tehran University of Medical Sciences, & Knowledge Utilization Research Center, Tehran University of Medical Sciences, Tehran, Iran.