Exam 1-Biostatistics

Question 1

Continous

Answer 1

variables that can theoretically have values between points (decimal points)-i.e. peoples weight/height

Question 2

discrete

Answer 2

no intermediate values (i.e. BP as hypotensive, normal, or hypertensive-OR number of students in a class)

Question 3

Central tendency

Answer 3

most frequently used is mean, very sensitive to outliers (mean, median, and mode)

Question 4

measures of dispersion

Answer 4

range (highest and lowest), interquartile range (75th percentile value minus 25th percentile value) and variance (spread data around the mean)

Question 5

Dependent variable

Answer 5

outcome of interest

Question 6

independent

Answer 6

risk factors or indicators of disease

Question 7

Parametric vs non-parametric

Answer 7

parametric: make an assumption about the underlying distribution

non-parametric: do not make any assumptions about the distribution, therefore considered robust

Question 8

Sample size determination-MED

Answer 8

minimum expected difference; smallest measured difference between comparison groups that the investigator would like the study to detect

Question 9

Sample size determination-p-value

Answer 9

probability that the finding is by chance; if P is LESS than .05 study is statistically SIGNIFICANT

Question 10

Sample size determination-Power

Answer 10

Ability to find a difference when there is a difference (80%) ,probability of rejecting the null hypothesis

Question 11

Sample size determination-Confidence interval

Answer 11

a range that you think will contain the true population parameter that you are measuring, it can be a measure of statistical significance and precision

Question 12

Sample size determination-Type 1 error

Answer 12

False discover, when we reject a true null hypothesis

Question 13

Sample size determination-Type 2 error

Answer 13

when we fail to reject the null hypothesis that is false