Cedrick
Forum Fanatic
Topics: 320
Posts: 1,928
|
the table reporst suvival patients who had an operation for a particular cancer form
Interval #patients #patients died %survival
at the begining
0-1year 300 115 62
1-2 185 37 80
2-3 148 24 84
3-4 124 18 85
4-5 106 25 76
if a patient survives 2 years after the operation,wich of the following is the probability of surviving at least 4 years ??
a.-0.80
b.-0.85
c.-0.84x0.85
d..-0.62x.80x.84x.85
e.-.85-.80
My guess is b
but knowing the test makers it woun't make sense so there it
Help
Thanks
|
| Cedrick
Forum Fanatic
Topics: 320
Posts: 1,928
|
ok then
|
| DrVirgo
Forum Hero
Topics: 1043
Posts: 3,345
|
Why do you say B?
Can you explain the answer? Thanks.
___________________
Our greatest glory is not in never falling, but in rising every time we fall.
|
| robin082006
Forum Hero
Topics: 471
Posts: 5,125
|
C
___________________
The Key to Succeed is Patience.
|
| DrVirgo
Forum Hero
Topics: 1043
Posts: 3,345
|
WHY C? Please explain. Thanks. 
___________________
Our greatest glory is not in never falling, but in rising every time we fall.
|
| robin082006
Forum Hero
Topics: 471
Posts: 5,125
|
This q is similar to Kaplan's
probability of surviving at least 3 years = 84 %
probability of surviving at least 4 years = 84%*85%
probability of surviving at least 5 years = 84%*85%*76%
we do not calculate the first two years because the patient has already survived 2 years. (the probability of surviving at least 1 years = 100% and the probability of surviving at least 2 years = 100%)
___________________
The Key to Succeed is Patience.
|
| Cedrick
Forum Fanatic
Topics: 320
Posts: 1,928
|
Thanks
Choice C
|
| docarchana
Forum Guru
Topics: 70
Posts: 515
|
yes C
|
| young_doc
Forum Guru
Topics: 55
Posts: 732
|
So if the patient was JUST told that he had cancer....then his chances of survival to 4 years are:
62 x 80 x 84 x 84?????????
I'm not saying that's not right, but it just doesn't make sense, because the 4 year survival percentage is already given!!!!!!!!!! EIGHTY-FOUR!
Can someone explain to me why i'm wrong?
___________________
First Aid is my Bible...
|
| klimt
Forum Guru
Topics: 27
Posts: 605
|
well I think the chance would have been indeed only 0.85 if the patient had made it to the third year. But he only made it to the second year so there's 0.84 chance to make it to the third and then another 0.85 to make it to the fourth....so 0.84*0.85 and that's C
___________________
Traveler, there are no roads. Roads are made by walking.
|
| GardenGuy
Forum Newbie
Topics: 5
Posts: 13
|
With only the number of pts given (not percentage), do you need to calculi the percentage before ending up with the answer?
|
| Musuq
Forum Guru
Topics: 103
Posts: 425
|
C then, thanks Robbins 
|
|
| |
| | | | | | | | | | | | |
