Please help ill give brainliest

A new screening test for Lyme disease is developed for use in the general population. The sensitivity and specificity of the new

Anit [1.1K]

Answer:

predictive value of a positive test = 18.18%

predictive value of a negative test = 94.03%

Step-by-step explanation:

Sensitivity = 60% = 0.6

Specificity = 70% = 0.7

Let True Positive = TP

True Negative = TN

False Negative = FN

$Sensitivity = \frac{TP}{TP + FN} \\0.6 = \frac{TP}{TP + FN} \\0.6TP + 0.6FN = TP\\0.4TP = 0.6FN\\TP = 1.5 FN$

$Specificity = \frac{TN}{TN + FP} \\0.7 = \frac{TN}{TN + FP} \\0.7TN + 0.7FP = TN\\0.7FP = 0.3 TN\\TN = 7/3 FP$

Prevalence = 10% = 0.1

Three hundred people are screened, $T_{total} = 300$

Total number of people having the disease, $T_{disease} = ?$

$Prevalence = \frac{T_{disease} }{T_{total} } \\0.1 = \frac{T_{disease} }{300 }\\T_{disease} = 30$

$T_{disease} = TP + FN\\30 = TP + FN$

But TP = 1.5 FN

30 = 1.5 FN + FN

30 = 2.5 FN

FN = 30/2.5

FN = 12

TP = 1.5 FN = 1.5 * 12

TP = 18

$FP + TN = T_{total} - T_{disease} \\FP + TN = 300 - 30\\FP + TN = 270\\FP + \frac{7}{3} FP = 270\\\frac{10}{3} FP = 270\\FP = 27 * 3\\FP = 81$

81 + TN = 270

TN = 189

To calculate the Predictive value of positive test (PPT)

$PPT = \frac{TP}{TP + FP} * 100\\PPT = \frac{18}{18+81} * 100\\PPT = \frac{18}{99} * 100\\PPT = 18.18 \%$

To calculate the Predictive value of negative test (PNT)

$PPT = \frac{TN}{FN + TN} * 100\\PPT = \frac{189}{189+12} * 100\\PPT = \frac{189}{201} * 100\\PPT = 94.03 \%$

7 0

3 years ago

Help me please!!!!!!

maks197457 [2]

To find the median, find the middle number. Since there are 10 numbers, find the 5th one and the 6th one and find their average.

The two numbers are both 9, so its safe to say that the median is 9.

to find the median of the first and quartile, you have to place a line where the median should be and find the median of that. Q1 and Q2 will be 5 and 11 (respectively).

Its easy to see that all the lines start at the lowest point given and end at the largest point given, so match Q1, the median, and Q3

The only line that has lines at the Q1, median, and Q3 we figured out is answer C, so therefore it is the answer.

8 0

3 years ago

Dave has $15 to spend on an $8 book and two baseball cards (c) costing $2 each. for his friends. Write an inequality to show how

kenny6666 [7]

The inequality would be 15-12

4 0

3 years ago

The equation of a linear function in point-slope form is y-y1=m(x-x1). Harold correctly wrote the equation y=3(x-7) using a poin

grin007 [14]

Answer:

(7, 0).

Step-by-step explanation:

We have y = 3(x - 7)

y = 3x - 21

Point-slope form is

y - y1 = 3(x - x1)

y - y1 = 3x - 3x1

Comparing this to the equation y = 4x - 21 we see that y1 = 0 and x1 = 7.

5 0

3 years ago

What is the least common multiple of 4, 5, and 12 ?

OLEGan [10]

Answer:

60

Step-by-step explanation:

4 0

3 years ago