RATES AND MEASURES in kaplan meier

Question

RATES AND MEASURES

1.    Review the distribution of COVID hospitalizations and deaths presented in the table below.

a)    Based on these data alone, would you conclude that being older ages is a risk factor for COVID 19 hospitalizations? Why or why not?

(Source: https://gis.cdc.gov/grasp/COVIDNet/COVID19_5.html)

Reported number of hospitalizations, United States, January 2, 2021

Age group Number of hospitalizations

0-4 658

5-17 1051

18-49 29,589

50-64 30,514

65+ 50,148

Total 111,960

b)    Based on these data alone, would you conclude that white non-Hispanic race/ethnicity is at highest risk from death due to COVID 19? Why or why not?

(Source: https://www.cdc.gov/nchs/nvss/vsrr/covid19/health_disparities.htm)

Reported number of deaths, United States, January 13, 2021

Race/ethnicity Number of deaths % of total COVID deaths

NH White 197,535 60.4%

NH Black 53,456 16.4%

NH AI/AN 3,704 1.1%

NH API 12,291 3.8%

Hispanic 60,140 18.4%

Total 327,126

2. There is anecdotal evidence to suggest that anxiety plays a role in causing the irritable bowel syndrome (IBS), a disorder characterized by nausea, alternating constipation and diarrhea, and no identifiable gastrointestinal pathology. To investigate this, researchers recruited 1500 people with a proven diagnosis of anxiety disorder and 1500 people without a diagnosis of anxiety disorder. At baseline, all participants were free of IBS symptoms (e.g., nausea, bowel habits), and every year participants were asked about their current IBS symptoms. Over the course of the study, 40 people with anxiety disorder reported IBS symptoms, while 25 of those without anxiety disorder reported these symptoms. The data manager reported that those with and without anxiety disorder were followed for an average of 4.5 and 4.8 years, respectively.

a.    Calculate the incidence of IBS symptoms among those with anxiety disorder in this study. Use the best measure of incidence given the available data.

b.    Why is the method that you chose in a less-than-ideal way to calculate the incidence of IBS symptoms among those with anxiety disorder in this sample. What are the limitations with the method you used in part A?

c.    Is anxiety disorder associated with IBS symptoms? Calculate the best measure of association and interpret this estimate

Answer 1

For the first two the immediate thing I see is that there is no reference to the percentage of the population these peoples represent. Perhaps 63% of the population is elderly, and they get it at the exact same rate as the rest of the population. Perhaps hispanics account for 5% of the population, and they account for 16% of the cases. This would be >3x what we would expect (5%). You always have to know what you are comparing a statistic to.