Evaluation of the impact of disease prevention measures: a methodological note on defining incidence rates

Table 3 RTS,S Malaria vaccine in Mozambican children, 2003–2005

Trial arm	Sample size	Number of event	Person-year at risk^a	Events/PYAR	Events/observation time^b
Control	745	384	972.1	0.395	0.383
RTS,S	745	310	1004.5	0.309	0.301
Overall	1490	694	1976.6	0.351	0.342

ISSN: 1471-2288