Table 4.

Cox regression analysis of risk of new Plasmodium falciparum infection by day 28

Parameter	Patientsa	Eventsa	HR (95 % CI)	P value
Univariable model
Day 7 lumefantrine concentration (log2)
Allb	2,528	180	0.79 (0.72 to 0.87)	<0.001
Venous plasma	1,336	40	0.65 (0.56 to 0.76)	<0.001
Capillary bloodb	663	130	0.87 (0.78 to 0.98)	0.002
Venous blood	529	10	0.82 (0.33 to 2.07)	0.619
Age (years)	2,528	180	0.95 (0.92 to 0.99)	0.009
Age category
< 1 year	73	9	3.51 (1.16 to 10.59)	0.026
1–4 years	1,004	148	5.01 (2.06 to 12.21)	<0.001
5–11 years	540	14	2.95 (1.17 to 7.39)	0.021
12+ years	911	9	Reference
Sex (female)	2,528 (1,157)	180 (93)	1.13 (0.84 to 1.51)	0.428
WAZ	1,076	157	0.86 (0.76 to 0.97)	0.015
Underweightc	1,076 (192)	157 (37)	1.22 (0.84 to 1.79)	0.299
Transmission intensity areas (TIAs)
Very low/lowd	557	9	0.17 (0.05 to 0.51)	0.002
Moderate	721	17	0.16 (0.05 to 0.56)	0.004
High	1,070	154	Reference
Multivariable model
Day 7 lumefantrine concentration (log2)e	2,528	180	0.70 (0.63 to 0.78)	<0.001
Location/transmission intensity area (TIA)
Very low/low/moderate TIA	1,304	26	0.22 (0.06 to 0.82)	0.024
High TIA
< 1 year	57	9	0.91 (0.27 to 3.05)	0.882
1–4 years	703	138	1.35 (0.49 to 3.74)	0.565
5+ years	464	7	Reference

^aNumber in brackets refers to patients with presence of the symptom/characteristic; ^b P value for testing proportional hazards assumption <0.05; ^conly evaluated in children <5 years of age and defined as weight-for-age Z-score (WAZ) < −2; ^dvery low and low TIAs were combined as no new infections were observed in very low TIA; ^efor concentrations measured on filter paper, the association with risk of new infection diminished after 21 days, hazard ratio = 1.062 (0.887–1.270), while for venous plasma this remained the same over the whole period. TIA, transmission intensity area