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# Detail about the ATLAS incident report

(Chidam) #1

Hi,

Find attached incident report screen result. Can any one please explain in details each items in the screen.
In the report case count always shows 0 why? what is proportion, time at risk , rate.

regards
Chidam

(Chris Knoll) #2

In your Hypertension cohort, you have 60,170 people. Zero (0) of those people had an outcome of Heart Disease in the specified time at risk. The total time at risk (from the 60,170 people starting at their time at risk start, up to their time at risk end) was 90 years.

Incidence proportion = cases / people = 0 / 60,170 = 0 cases per person
Incidence rate = cases / time at risk = 0 / 90 = 0 cases per year.

Your IR analysis includes a sub group: ‘Age Criteria’. There are 59,385 people in that sub-group, but you still have 0 cases, so your IR and IP will be 0, but notice Time at risk is now 89 years.

Something seems odd the way you’ve defined your time at risk: 60k people only contributed 90 years (~33k days) of follow up? And considering the follow-up is so short, it may explain why you found no cases.

(Christian Reich) #3

90 years for 60k people? That like half a day per person. How did you define time at risk, @Chidam?

(Chidam) #4

My IR configuration

Time at Risk : starts 0 days to 548 days

thanks
regards
Chidam

(Chidam) #5

Thanks Chris,