Table 1. Vaccine Efficacy.^*.

Variable	RTS,S/AS01 Vaccine				Control				Efficacy (95% CI)	P Value
	No. of Participants	No. of Events	Person-Yr at Risk	Event Rate	No. of Participants	No. of Events	Person-Yr at Risk	Event Rate
Intention-to-treat cohort
First episode, Cox regression
>2500 parasites/mm3	223	150	668.0	0.22	224	157	501.6	0.31	27.0 (8.5 to 41.8)	0.006
>0 parasites/mm3	223	158	622.9	0.25	224	163	470.1	0.35	25.6 (7.2 to 40.3)	0.009
Multiple episodes, negative binomial regression
>2500 parasites/mm3	223	1002	1372.8	0.73	224	992	1282.5	0.77	4.4 (−17.0 to 21.9)	0.66
>0 parasites/mm3	223	1157	1372.8	0.84	224	1164	1282.5	0.91	4.7 (−15.3 to 21.3)	0.62
Per-protocol cohort
First episode, Cox regression
>2500 parasites/mm3	209	139	605.6	0.22	206	145	440.3	0.33	33.8 (16.4 to 47.6)	0.001
>0 parasites/mm3	209	144	567.8	0.25	206	151	412.5	0.37	34.1 (17.1 to 45.6)	<0.001
Multiple episodes, negative binomial regression
>2500 parasites/mm3	209	889	1223.6	0.73	206	844	1109.2	0.76	7.0 (−14.5 to 24.6)	0.52
>0 parasites/mm3	209	1021	1223.6	0.83	206	990	1109.2	0.89	8.6 (−11.4 to 25.0)	0.37

^*The control group received a rabies vaccine. All clinical malaria cases were detected by active case detection or passive case detection. Vaccine efficacy was defined as 1 minus the hazard ratio or the incidence-rate ratio, then multiplied by 100. P values were calculated with the use of a Cox proportional-hazards model for first episodes and negative binomial regression for multiple episodes.