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Re: Disease Detectives B/C
Posted: May 3rd, 2015, 7:44 am
by SOnerd
I've done disease since ~January, and I haven't really ever studied pop growth. I know that the growth of a population can influence the spread of disease because people live in closer quarters, but I don't really know anything else about it. What else should we know about Pop Growth?
Re: Disease Detectives B/C
Posted: May 3rd, 2015, 8:43 am
by sciolyboy123
Definetly the math involved with population. I have yet to take a test this year that doesn't have at least one of the following: Incidence Rate, Prevalence Rate, Case-Fatality Rate, Mortality Rate, Natality Rate, etc. Just make sure you know the formulas for basically all pop. growth math problems.
Re: Disease Detectives B/C
Posted: May 3rd, 2015, 2:45 pm
by UTF-8 U+6211 U+662F
SOnerd wrote:I've done disease since ~January, and I haven't really ever studied pop growth. I know that the growth of a population can influence the spread of disease because people live in closer quarters, but I don't really know anything else about it. What else should we know about Pop Growth?
Different types of pop growth diseases, the problems of pop growth, exposures like asbestos and air pollution, etc.
Re: Disease Detectives B/C
Posted: May 3rd, 2015, 3:47 pm
by JoJoKeKe
Hello everyone!
I'm competing in Disease Detectives in the National Competition representing Idaho, but I had a question...
Definetly the math involved with population. I have yet to take a test this year that doesn't have at least one of the following: Incidence Rate, Prevalence Rate, Case-Fatality Rate, Mortality Rate, Natality Rate, etc. Just make sure you know the formulas for basically all pop. growth math problems.
I had never learned Incidence Rate, Prevalence Rate, Case-Fatality Rate, Mortality Rate, and Natality Rate. After looking up the formulas and adding them to my reference sheet I had one question: are all these represented in percentages?
If not, could you tell me how I would write them to receive points? Thank you!

Re: Disease Detectives B/C
Posted: May 3rd, 2015, 4:05 pm
by UTF-8 U+6211 U+662F
JoJoKeKe wrote:Hello everyone!
I'm competing in Disease Detectives in the National Competition representing Idaho, but I had a question...
Definetly the math involved with population. I have yet to take a test this year that doesn't have at least one of the following: Incidence Rate, Prevalence Rate, Case-Fatality Rate, Mortality Rate, Natality Rate, etc. Just make sure you know the formulas for basically all pop. growth math problems.
I had never learned Incidence Rate, Prevalence Rate, Case-Fatality Rate, Mortality Rate, and Natality Rate. After looking up the formulas and adding them to my reference sheet I had one question: are all these represented in percentages?
If not, could you tell me how I would write them to receive points? Thank you!

Most of them are represented in percentages, yes. Why are they called rates?

Besides, I don't think the ES will care if you did/didn't write it in percent form.
Re: Disease Detectives B/C
Posted: May 3rd, 2015, 4:15 pm
by JoJoKeKe
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?
Re: Disease Detectives B/C
Posted: May 3rd, 2015, 4:22 pm
by UTF-8 U+6211 U+662F
JoJoKeKe wrote: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
Re: Disease Detectives B/C
Posted: May 3rd, 2015, 5:01 pm
by JoJoKeKe
Okay, thank you.
One example was that out of 100 cases of Tuberculosis, 40 died. Would you simply not include the time if it was not given? (As the CFR is obviously 40%)
Re: Disease Detectives B/C
Posted: May 3rd, 2015, 5:03 pm
by UTF-8 U+6211 U+662F
JoJoKeKe wrote:Okay, thank you.
One example was that out of 100 cases of Tuberculosis, 40 died. Would you simply not include the time if it was not given? (As the CFR is obviously 40%)
Yes.
Re: Disease Detectives B/C
Posted: May 3rd, 2015, 6:25 pm
by sciolyboy123
UTF-8 U+6211 U+662F wrote:JoJoKeKe wrote: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.