“…Although some current studies use also Fog index (Lo et al, 2017;Lim et al, 2018), we detected also application of FRE readability measure (Moffitt & Burns, 2009), texture index (Sydserff & Weetman, 1999, p. 475), Cloze procedure (Adelberg, 1979;Smith & Taffler, 1992), Lix (Smith & Taffler, 1992), Flesch Fog, Lix (Courtis, 1995), the Gunning measure of readability (Heath & Phelps, 1984), C-Test, the MIT test and the The Science Virtual Test SVT test (Jones & Smith, 2014). However, further based on the basic predictions of the readability theories, researchers began to raise questions on why variability in readability occurs?…”