L2- Clinical Epidemiology Intro

Question 1

define EBM

Answer 1

(evidence based medicine)

application of clinical epidemiology to the care of individual patients

Question 2

compare ordinal to nominal

Answer 2

in ordinal, order is essential

in nominal order doesn’t matter and is arbitrary

Question 3

define mode, in terms of distribution curve

Answer 3

the most frequently occurring data point

Question 4

SD = ____________

Answer 4

(standard deviation)

SD = sqrt(Variance)

Question 5

plus or minus one SD from the mean includes __% of all data points

Answer 5

68% (34% either direction from mean)

Question 6

plus or minus two SD from the mean includes __% of all data points

Answer 6

95% (47.5% either direction from mean, 13.5% beyond one SD in either direction)

Question 7

plus or minus three SD from the mean includes __% of all data points

Answer 7

99% (2% beyond two SDs in either direction)

Question 8

a negatively skewed distribution can also be called…. (2 names)

Answer 8

Right Modal
Left Skewed
(peak is towards R side)

Question 9

a positively skewed distribution can also be called…. (2 names)

Answer 9

Left Modal
Right Skewed
(peak is towards L side)

Question 10

negative skewed distribution has a peak towards (R/L) side

Answer 10

Right side (Right Modal, Left Skewed)

Question 11

positively skewed distribution has a peak towards (R/L) side

Answer 11

Left side (Left Modal, Right Skewed)

Question 12

describe order of mean, median, and mode values in a symmetrical distribution

Answer 12

mean = median = mode

Question 13

describe order of mean, median, and mode values in a positively skewed distribution

Answer 13

mode < median < mean

L sided peak

Question 14

describe order of mean, median, and mode values in a negatively skewed distribution

Answer 14

mean < median < mode

R sided peak

Question 15

a data set with two peaks is called….

Answer 15

bimodal distribution

Question 16

validity refers to (accuracy/precision)

Answer 16

accuracy (is measurement representative of its actual value)

Question 17

reliability refers to (accuracy/precision)

Answer 17

precision (consistency, reproducibility- extent that repeated measurements are accurate)

Question 18

what are some sources of variation in clinical measurements

Answer 18

Biological variation: within individuals (intra-variability), between individuals (inter-variability)

Measurement variation: instrumental, observer