Bladder Cancer From Coffee Drinking Among Smokers
Investigators were interested in analyzing the association between coffee consumption and bladder cancer after reading an article that described that coffee consumption was positively associated with risk of pancreatic cancer. They conducted a retrospective cohort study in which they included cancer-free patients aged 50 -65 years who were members of Kaiser Permanente (HMO) between 2000 and 2015 and had sought medical care in 2000 . They extracted information on coffee consumption in 2000 as well as demographic and general behavioral information from medical records. They selected 5,480 participants who drank 1 or more cups of coffee per day and 5,480 participants who did not drink coffee. The study found that among those who did not drink coffee, 152 developed bladder cancer. Among those who drank coffee, 650 developed bladder cancer. Round all your calculations to 2 decimal points a. Create a table to compare those who drink coffee vs. not with the bladder cancer: b. Calculate the relative risk (RR) of bladder cancer from drinking coffee. Show your work (formula/set-up and calculation). c. Does coffee drinking appear to be harmful or protective with regard to bladder cancer? Why? As a part of the design of the study, the epidemiologist obtained information about the patients’ smoking habits (smokers vs. nonsmokers) for most but not all the participants. Smoking could be a confounder. Results from the study were as follows: Table 1. Association between coffee drinking and bladder cancer amonosmokers Table 2. Association between coffee drinking and bladder eancer amonenon-smokers d. Calculate the RR of bladder cancer from coffee drinking among the smekers. Show your work (formula/set-up and calculation). e. Calculate the RR of bladder cancer from coffee drinking among the non-smokers. Show your work (formula/setup and caleulation). f. Multiple choice: Which of the following is demonstrated by the stratified risk ratio shown above? . Confounding by smoking B. Effect modification by smoking C. Selection bias by smoking D. Recall bias by smoking E. Residual confounding by other factors that differ by smoking such as exercise activity g. Multiple choice: Based on the responses above, what is the most appropriate measure of association to present when reporting the results of this study? A. The crude risk ratio B. The weighted average of the stratum-specific risk ratios C. The separate stratum-specific risk ratios D. The risk ratio after adjustment for smoking E. None of the above; an incidence study should be done that better describes the relationship Bladder Cancer From Coffee Drinking Among Smokers
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Step 1/3
a. Table showing the following data:
|
|
Bladder cancer(+
|
Bladder cancer(-
|
total
|
|
coffee drinking
|
650
|
4830
|
5480
|
|
coffee drinking
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152
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5338
|
5490
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|
total
|
802
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10168
|
10970
|
b.
The relative risk (RR) of bladder cancer from drinking coffee can be calculated using the formula:
RR = (a / (a + b)) / (c / (c + d))
where a is the number of people who drank coffee and developed bladder cancer, b is the number of people who drank coffee and did not develop bladder cancer, c is the number of people who did not drink coffee and developed bladder cancer, and d is the number of people who did not drink coffee and did not develop bladder cancer.
Using the numbers from the table, we get: Bladder Cancer From Coffee Drinking Among Smokers
RR = (650 / (650 + 4830)) / (152 / (152 + 5338)) = 1.48
c.
Coffee drinking appears to be harmful with regard to bladder cancer because the RR is greater than 1. This means that people who drink coffee have a higher risk of developing bladder cancer compared to those who do not drink coffee. However, it is important to note that this is an observational study, and other factors (such as smoking, diet, or other lifestyle factors) may be contributing to the observed association.
Explanation:
in the next step there is a more detailed explanaition how i did this.
Step 2/3
Here’s a more detailed explanation of how I approached each part of the question:
a.
To create the 2×2 table, we need to classify the participants into four categories based on their coffee consumption and bladder cancer status. The categories are: coffee drinkers with bladder cancer, coffee drinkers without bladder cancer, non-coffee drinkers with bladder cancer, and non-coffee drinkers without bladder cancer. We can then count the number of participants in each category and fill in the table accordingly.
b.
To calculate the relative risk (RR) of bladder cancer from drinking coffee, we use the formula:
RR = (a / (a + b)) / (c / (c + d))
where a is the number of people who drank coffee and developed bladder cancer, b is the number of people who drank coffee and did not develop bladder cancer, c is the number of people who did not drink coffee and developed bladder cancer, and d is the number of people who did not drink coffee and did not develop bladder cancer.
Using the numbers from the table, we get:
RR = (650 / (650 + 4830)) / (152 / (152 + 5338)) = 1.48
The RR value of 1.48 indicates that coffee drinkers have 1.48 times the risk of developing bladder cancer compared to non-coffee drinkers.
c.
To interpret the RR value, we compare it to 1. If the RR is greater than 1, as it is in this case (RR = 1.48), it means that coffee drinking appears to be harmful with regard to bladder cancer. If the RR is less than 1, it means that coffee drinking appears to be protective or beneficial. If the RR is equal to 1, it means that there is no association between coffee drinking and bladder cancer.
Explanation:
this is how i approached it in detailed explanation .
Step 3/3
Moving on further to the next step for answering d,e,f,g :
d.
RR of bladder cancer from coffee drinking among smokers = (a/(a+b)) / (c/(c+d))
RR = (170/(170+115)) / (1233/(1233+1314)) = 1.27
e.
RR of bladder cancer from coffee drinking among non-smokers = (a/(a+b)) / (c/(c+d))
RR = (152/(152+142)) / (3558/(3558+3324)) = 0.93
f. The stratified risk ratio shown above demonstrates :
B. effect modification by smoking, as the effect of coffee drinking on bladder cancer risk differs between smokers and non-smokers.
g. The most appropriate measure of association to present when reporting the results of this study : Bladder Cancer From Coffee Drinking Among Smokers
C.the separate stratum-specific risk ratios for smokers and non-smokers. This is because smoking is a potential confounder, and presenting separate stratum-specific risk ratios allows for the effect of coffee drinking on bladder cancer risk to be evaluated independently among smokers and non-smokers.
Explanation:
ILL EXPLAIN IN DETAIL HOW I DID THE CALCULATION IF YOU UNDERSTAND SO ….
First, we need to calculate the incidence of bladder cancer among coffee drinkers and non-coffee drinkers among smokers.
The incidence of bladder cancer among coffee drinkers (a/(a+b)) = 170/(170+115) = 0.596.
The incidence of bladder cancer among non-coffee drinkers (c/(c+d)) = 1233/(1233+1314) = 0.484.
Next, we can calculate the relative risk (RR) of bladder cancer from coffee drinking among smokers:
RR = (incidence of bladder cancer among coffee drinkers) / (incidence of bladder cancer among non-coffee drinkers)
RR = 0.596 / 0.484 = 1.23
Therefore, the relative risk of bladder cancer from coffee drinking among smokers is 1.23.
Similarly, for Table 2, to calculate the RR for bladder cancer from coffee drinking among non-smokers, we use the values a=152, b=142, c=3558, and d=3324.
The incidence of bladder cancer among coffee drinkers (a/(a+b)) = 152/(152+142) = 0.517.
The incidence of bladder cancer among non-coffee drinkers (c/(c+d)) = 3558/(3558+3324) = 0.517.
RR = (incidence of bladder cancer among coffee drinkers) / (incidence of bladder cancer among non-coffee drinkers)
RR = 0.517 / 0.517 = 1
Therefore, the relative risk of bladder cancer from coffee drinking among non-smokers is 1.
Final answer
This is how the results from study were as follows for Table no.1 and Table no.2 .
Bladder Cancer From Coffee Drinking Among Smokers