Disease Detectives B/C

[JoJoKeKe]

So for the CFR you never multiply by 100 at the end???

[UTF-8 U+6211 U+662F]

Thank you! That is what I assumed.

And, just to make sure I have the formulas correct based off of my research, the formulas are:

Incidence Rate:
New cases over a time period / Population at risk during that time period

Prevalence Rate:
(Persons with a given health problem / Population in that time period) x100

Natality Rate:
(Number of births in a population in a time / Total population) x1,000

Mortality Rate:
(Deaths during a time period / size of the population during a time period) x100 or 10,000 (depending)

Case-Fatality Rate:
(Number of Deaths within a given time period / Number of Cases within a given time period) x100
-------------------------

Correct?

Well, the incidence rate is new cases/population at risk/time period, okay?
Same thing with the CFR: Number of deaths/number of cases/time period

NOOOO, Incidence is new cases/total population at risk,
same thing with CFR. Number of deaths/number of cases.

Well, I guess it depends on who you ask.

[sciolyboy123]

The reason time period isn't involved in the calculation because you can't really represent it.....

Example: 40 people are infected with tuberculosis, with 100 people being at risk to contract disease in 2013.

The incidence rate of 2013 is 0.4 or 40%

Hope you understand now.

[JoJoKeKe]

So do you only multiply by 100 if you don't want your answer in decimal form? (That's how it appears to me...)

[UTF-8 U+6211 U+662F]

So do you only multiply by 100 if you don't want your answer in decimal form? (That's how it appears to me...)

You multiply by 100 to either get it into percent form or fraction form.

The reason time period isn't involved in the calculation because you can't really represent it.....

Example: 40 people are infected with tuberculosis, with 100 people being at risk to contract disease in 2013.

The incidence rate of 2013 is 0.4 or 40%

Hope you understand now.

40%... per year.

[sciolyboy123]

That's right.

[UTF-8 U+6211 U+662F]

That's right.

So you're suggesting that it technically does include the time period?

[sciolyboy123]

Technically, but not in the calculation.

[UTF-8 U+6211 U+662F]

Technically, but not in the calculation.

Well, same example but over two years:

Example: 40 people are infected with tuberculosis, with 100 people being at risk to contract disease in 2013 & 2014.

The incidence rate is 40% over 2 years.
The incidence rate is 20% per year.

40/100/2 = 20%

[sciolyboy123]

Yes. In that case, it would be right.