1. To test the efficacy of the HPV vaccine to prevent HPV related throat cancer, researchers have examined 400 cases from a case-control study. Among the total population examined, 200 were exposed to HPV vaccine and 200 not. Among those who had HPV vaccine, 10 developed throat cancer from a total of 90 cases.

	Throat cancer (yes)	Throat cancer (no)	Total
HPV vaccine (yes)	[a]	[b]	[c]
HPV vaccine (no)	[d]	[e]	[f]
Total	[g]	[NonDisease_Total]	[Total_N]

1. Complete the table above.

1. Calculate the incidence of throat cancer among those who received HPV vaccine.
   1. 0.19
   2. 0.90
   3. 0.05
   4. 0.23