Table 3.

Post hoc Bonferroni pairwise test of distribution of anemia and its parameters among different stages of CKD in black South Africans

Parameter	Post hoc Bonferroni test across stages
Hb	There was a statistically significant decrease in mean Hb levels between stage V and stages I, II, IIIa, IIIb, and IV (P-value <0.001)
MCV	There was a statistically significant difference in MCV between stage IV and stages II and IIIb (stage IV vs stage II, P-value <0.001; stage IV vs stage IIIb, P-value =0.009); the mean MCV of stage V CKD was also statistically different from stage II (stage V vs stage II, P-value =0.021)
MCH	There was a statistically significant difference in mean MCH between stage IV and stages II, IIIa, and IIIb (stage IV vs stage II, P-value <0.001; stage IV vs stage IIIa, P-value =0.042; stage IV vs stage IIIb, P-value =0.027). Also, the mean MCH of stage V CKD was statistically different from stage II (stage V vs stage II, P-value =0.003)
CRP	The mean CRP levels among stage V CKD patients were statistically different from those of stages I (P-value =0.030), IIIa (P-value =0.008), IIIb (P-value =0.005), and IV (P-value =0.003)

Abbreviations: CKD, chronic kidney disease; CRP, C-reactive protein; MCH, mean corpuscular hemoglobin; MCV, mean corpuscular volume.