In 2019, Ioannidis et al. (PLoS Biol 17(8): e3000384, DOI: 10.1371/journal.pbio.3000384) published the results of a meta-analysis of the world's nearly 7 million working researchers in 22 scientific fields and 176 subfields ranging from chemistry, physics, engineering, economics and business.

The 2021 list of world top 2% researchers includes about 190,000 top scientists from all over the world (see the full list available on: DOI:10.17632/btchxktzyw.3).

The top 2% scientists were selected based on their academics’ scientific achievements measured by the standardized information on citations, h-index, co-authorship adjusted hm-index, citations to papers in different authorship positions and a composite indicator.

Associate Professor Muhammad J. A. Shiddiky has been ranked 99,375th for his output in 2021-based ranking, improving from 106,839th in 2020. He has also been ranked at 652 from 102,767 scientists in Analytical Chemistry, improving from 777 out of 87,137 scientists.