Table 4. Comparative mean [one-way ANOVA (post-hoc)] analysis of different serum parameters across different grades identified in brain tumour patients who participated, Addis Ababa, Ethiopia, 2020.

Serum parameter	Tumour grade
	Grade I (N = 21) Mean ± SD	Grade II (N = 14) Mean ± SD	Grade III (N = 9) Mean ± SD	Grade IV (N = 6) Mean ± SD
GSH	11.96 ± 1.13a	11.10 ± 0.97a	10.14 ± 0.22	9.46 ± 0.46
GSSG	0.69 ± 0.02b	0.71 ± 0.015b	0.75 ± 0.029	0.74 ± 0.035
TOS	8.43 ± 1.56c	9.46 ± 0.77c	11.31 ± 0.79	11.96 ± 0.72
TAC	93.80 ± 4.49d	84.89 ± 8.39d	57.89 ± 7.25d	50.55 ± 3.14d
OSI	9.11 ± 1.79e	11.26 ± 1.54e	19.87 ± 3.25e	23.78 ± 2.65e

^aSignificant mean difference in GSH

^bSignificant mean difference in GSSG

^cSignificant mean difference in TOS

^dSignificant mean difference in TAC

^eSignificant mean difference in OSI