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incidence

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6 Posts

nadiabarati

06/06/06 - 06:39 AM

800 MOTOR VEHICLE COLLISIONS OCCURED OVER 2 YEARS IN A CITY WITH A POPULATION OF 600000: 600 OF THESE ACCIDENTS WERE ALCOHOL RELATED.DURING THE SAME PERIOD, THERE WERE 400 FATALITIES DUE TO MOTOR VEHICLE COLLISIONS, OF WHICH 75% WERE ALCOHOL RELATED.WHICH OF FOLLOWING BEST REPRESENTS 1 YEAR INCIDENCE OF ALCOHOL RELATED MOTOR VEHICLE FATALITIES IN THIS COMMUNITY?

1.150 PER 600000

2.300 PER 600000

3.450 PER 600000

4.600 PER 600000

5.UNABLE TO DETERMINE FROM AVAILABLE INFORMATION

Please try this one more time. I think the answer is 5. Because we can not divide the new cases of two years for getting incidence We don't know how many happened in each year. Thanks for any input.

asankineni
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Topics: 5
Posts: 10

06/22/06 - 12:29 PM

I think it is 5. Since the denopminator should be at risk population. He has given total population in the city and not the pop with Motor vehicles. And also as u said it is given as 2 yrs

mjl1717
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06/22/06 - 12:34 PM

ill go with answer 5 also {i remember this q}

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zubr
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Topics: 14
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06/22/06 - 08:23 PM

Never give up!!!

Q: INCIDENCE OF ALCOHOL RELATED MOTOR VEHICLE FATALITIES IN THIS COMMUNITY?

Incidence = Numerator (actual cases) / Denominator (at risk)

ALCOHOL RELATED MOTOR VEHICLE FATALITIES = Death from motor vehicle accident under influence of alcohol:
400 FATALITIES DUE TO MOTOR VEHICLE COLLISIONS, OF WHICH 75% WERE ALCOHOL RELATED= 400 x 75% = 300 per 2 years = 150 per 1 year.

At risk: population of this city: CITY WITH A POPULATION OF 600000

ANSWER: (150 per 600 000) #1

Case-fatality rate = Death from a specific cause(in our case: ALCOHOL RELATED MOTOR VEHICLE DEATH) per number of person with the disease(in our case: ALCOHOL RELATED MOTOR VEHICLE ACCIDENTS).

400 FATALITIES DUE TO MOTOR VEHICLE COLLISIONS, OF WHICH 75% WERE ALCOHOL RELATED per 2 years: 300 per 2 years = 150 per 1 year.

600 OF THESE ACCIDENTS WERE ALCOHOL RELATED per 2 years: 300 per 1 year.

fatality rate = 150/300 = 50% (could guess by Kaplan lectures)

Edited by zubr on 06/22/06 - 08:30 PM

tolito
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06/27/06 - 12:32 PM

this question was framed differently in qbank but same figures and the answer was A. as explained by zubr.

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mjl1717
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06/27/06 - 01:54 PM

zubr wrote:
Never give up!!!

Q: INCIDENCE OF ALCOHOL RELATED MOTOR VEHICLE FATALITIES IN THIS COMMUNITY?

Incidence = Numerator (actual cases) / Denominator (at risk)

ALCOHOL RELATED MOTOR VEHICLE FATALITIES = Death from motor vehicle accident under influence of alcohol:
400 FATALITIES DUE TO MOTOR VEHICLE COLLISIONS, OF WHICH 75% WERE ALCOHOL RELATED= 400 x 75% = 300 per 2 years = 150 per 1 year.

At risk: population of this city: CITY WITH A POPULATION OF 600000

ANSWER: (150 per 600 000

Case-fatality rate = Death from a specific cause(in our case: ALCOHOL RELATED MOTOR VEHICLE DEATH) per number of person with the disease(in our case: ALCOHOL RELATED MOTOR VEHICLE ACCIDENTS).

400 FATALITIES DUE TO MOTOR VEHICLE COLLISIONS, OF WHICH 75% WERE ALCOHOL RELATED per 2 years: 300 per 2 years = 150 per 1 year.

600 OF THESE ACCIDENTS WERE ALCOHOL RELATED per 2 years: 300 per 1 year.

fatality rate = 150/300 = 50% (could guess by Kaplan lectures)

this is reasonable

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