“…Table XII lists the techniques used to evaluate the studies. The subjective evaluation method was commonly applied to evaluate TTS systems, and the most commonly used method was the Mean Opinion Score (MOS) test [88], [92], [93], [94], [99], [103], [104], [105], [61], [106], [108], [110], [112], [114], [115], [117], [118], [119]. Categorial estimation (CE) tests, preference test [102], [108], [117], DMOS test [108], and DRT tests [87], [96], [116] have also been used as subjective evaluation tests in some studies.…”