“…The current study adds following vital contributions to existing literature: (a) our research goes beyond investigating the enhancing influence of trade openness and economic growth and further studies the impact of other plausible variables such as human capital (Saba & Abbas, 2016: Affandi et al, 2019), institutional performance (Erum & Hussain, 2019; Gründler & Potrafke, 2019) and public expenditure (Ahuja & Pandit, 2020; Lupu et al, 2018) on economic growth of OIC countries by dividing them into different income groups, (b) unlike previous studies, we use a novel method “dynamic common correlated effects (DCCE)” to tackle with various problems like cross‐sectional dependence (CD), heteroscedasticity and heterogeneity, (c) in previous works, the typical proxy for trade openness is used, which is calculated as the nominal values of imports plus exports divided by nominal GDP, but, in this study, the real trade openness is used which is defined as value of exports plus imports (constant 2010US$) divided by GDP (constant 2010 US$ and adjusted for purchasing power parity). The use of real trade openness helps us to consider the purchasing power of each country, (d) our study does not rely on the traditional measures of human capital like schooling (Ogundari & Awokuse, 2018; Siddiqui & Rehman, 2017), life expectancy (He & Li, 2019; Ogundari & Awokuse, 2018) and expenditure on health (Piabuo & Tieguhong, 2017; Wang et al, 2019) and uses the recently developed index of human capital provided by the Penns World Table which is believed a superior measure as it captures the multidimensional aspects of human capital and based on average years of schooling 1 and the returns to education 2 (Feenstra et al, 2015). (e) previous studies use a single indicator to represent institutional performance like government stability (Alper, 2018; Yakubu et al, 2020), control of corruption (Anh et al, 2016; Wang et al, 2018), law and order (Salman et al, 2019), etc.…”