Table 4.

Critical assessment of the quality of the selected manuscripts according to Newcastle–Ottawa scale: cohort and case control studies [101].

	Selection (Star Number)	Comparability (Star Number)	Outcome (Star Number)
Bais et al. [89]	3	1	3
Puanglumyai et al. [71]	2	Not applicable †	2
Del Bigio et al. [94]	4	1	2
Delteil et al. [95]	2	Not applicable †	2
Zuccoli et al. [96]	1	Not applicable †	3
Moskwa et al. [97]	3	Not applicable †	2
Oliva et al. [99]	1	Not applicable †	3
Bulirsch et al. [100]	2	1	3

^† Comparability method not applicable in cohort studies.