a. If no one dropped out of the study and no one developed Chlamydia infection during the study period, the total number of person-years = 10,000 person-years (2,000 x 5 years).
Person-years are the product of the number of people in a study and the amount of time each person spends in the study.
Thus, since there are 2,000 women in this study, who spend 5 years each, the person-years are 10,000 (2,000 x 5) person-years.
b. The estimated incidence rate of Chlamydia infection among women who participated in the study is 0.62 or 620 per 1,000 person-years (6,200/10,000).
An incidence rate describes the quickness of disease occurrence in a population. Since the incidence rate is based on person-time, it has some advantages over an incidence proportion, which measures the probability of developing a disease during the specified period.
Sample of young women = 2,000
Period of study = 5 years
Subjects newly diagnosed with infection = 440
Total number of person-years of subjects diagnosed = 6,200
Thus, the total number of person-years in the study is 10,000 person-years, while the incidence rate is 620 per 1,000.
Learn more about incidence rates at https://brainly.com/question/24493066