Question

copy of
use the scenario below:
a cohort study of 5,000 participants looked at the association between tamoxifen (exposure) and uterine cancer (outcome). at baseline,
235 women already had uterine cancer. among those eligible to participate, there were a total of 1,250 women taking tamoxifen and the
remaining women were not. of those taking tamoxifen, 95 developed uterine cancer. of those not taking tamoxifen, 159 developed
the uterine cancer.
blank cells in the table. use the label in each cell to fill in the blanks.

Explanation:

Step1: Calculate the number of women taking Tamoxifen with uterine cancer

Given that among those taking Tamoxifen, 95 developed uterine cancer. So for Tamoxifen - Yes and Uterine Cancer - Yes: $95$

Step2: Calculate the number of women taking Tamoxifen without uterine cancer

Total women taking Tamoxifen is $1250$. Number with uterine cancer is $95$. So number without is $1250 - 95=1155$

Step3: Calculate the number of women not taking Tamoxifen

Total participants $5000$, $235$ had uterine cancer at baseline. So eligible participants $5000 - 235 = 4765$. Women taking Tamoxifen $1250$, so women not taking Tamoxifen $4765-1250 = 3515$

Step4: Calculate the number of women not taking Tamoxifen with uterine cancer

Given $159$ developed uterine cancer. So for Tamoxifen - No and Uterine Cancer - Yes: $159$

Step5: Calculate the number of women not taking Tamoxifen without uterine cancer

Number of women not taking Tamoxifen $3515$, number with uterine cancer $159$. So number without is $3515 - 159=3356$

Step6: Calculate the total number of women with uterine cancer

At baseline $235$, among Tamoxifen takers $95$ developed (but baseline $235$ are excluded from the analysis as they already had it. Wait, no, re - evaluate.
Wait, total participants $5000$. At baseline $235$ had uterine cancer. Eligible participants (those without at baseline) $5000 - 235=4765$. Among eligible, Tamoxifen takers $1250$ (of which $95$ developed), non - takers $3515$ (of which $159$ developed).
Total with uterine cancer (during study) $95 + 159=254$. Total without (during study) $1155+3356 = 4511$. Total (during study) $254 + 4511=4765$ (matches eligible).

Answer:

	Uterine Cancer		Total
Tamoxifen - Yes	$95$	$1155$	$1250$
Tamoxifen - No	$159$	$3356$	$3515$
Total	$254$	$4511$	$4765$