Table 6. Covariation of resistance to third generation cephalosporins, chloramphenicol, co-trimoxazole and gentamicin among gram-negative bacteria, paediatric cohort.

Observed number of isolates expressing resistance to 0–4 antibiotics compared with expected randomly distributed co-resistance (N = 87).

Frequencies	Expected	Observed (CI)	Relative risk
0	1.8	15 (8.7–23.3)	8.3
1	11.9	11 (5.6–18.7)	0.9
2	29.4	8 (3.5–15.1)	0.3
3	31.5	24 (16.1–33.2)	0.8
4	12.5	29 (20.5–38.5)	2.3