Decisive the prevalence, incidence, risk of developing, total number of person-years at risk and incidence rate of cervical cancer.

In 1999 4458 women were screened for cervical cancer as well as 72 were found to have CIN three stage or above (diagnostic of carcinoma of the cervix or carcinoma-in-situ). The women who didn't have cervical cancer were re-screened in 2004 also another 40 cases were diagnosed.

a) describe what was the prevalence of cervical cancer in 1999 and 2004?

b) describe How many women were at risk of developing cervical cancer before being screened in

1) 1999 and

2) 2004?

3) describe what was the incidence of cervical cancer in these women and is this a measure of cumulative incidence or incidence rate?
Presume that on average each of the 30 women who were diagnosed with cervical carcinoma did so half-way through during the five-year period.

4) Compute the total number of person-years at risk of developing cervical cancer during the five years.

5) describe what is the incidence rate of cervical cancer in these women?