Biostatistics

Question 1

What does ANCOVA stand for??

Answer 1

Analysis of covariance

Question 2

What does ANOVA stand for?

Answer 2

Analysis of variance

Question 3

What are two types of random variables?

Answer 3

Discrete variables (including dichotomous and categorical) and continuous variables

Question 4

What are variables that have a limited number of values within a given range? (Discrete or Continuous)

Answer 4

Discrete

Question 5

What are variables that can take on any value within a given range? (Discrete or Continuous)

Answer 5

Continuous

Question 6

Are nominal and ordinal variables discrete or continuous?

Answer 6

Discrete

Question 7

What are discrete variables that are classified into groups, but have no order or rank?

Answer 7

Nominal variables

Question 8

What are discrete variables that are ranked in a specific order, but with no consistent size or magnitude of difference between ranks?

Answer 8

Ordinal variables

Question 9

Sex, mortality, disease presence, race, and marital status are examples of what type of discrete variables?

Answer 9

Nominal

Question 10

The functional status of patients with heart failure, classified in increasing order of disease severity, is what type of discrete variable?

Answer 10

Ordinal

Question 11

What are three visual methods of describing data (visuals for descriptive statistics)?

Answer 11

Frequency distribution, histogram, and scatterplot

Question 12

What is it called when you convert data to their log values and calculate the mean, which results in the conversion of a skewed to a normal distribution?

Answer 12

Geometric mean

Question 13

Which measure of central tendency is more appropriate if you have significant outliers in your data, mean or median?

Answer 13

Median

Question 14

Name the three measures of central tendency

Answer 14

Mean, median, and mode

Question 15

Name three measures of sample spread or sample variability

Answer 15

Standard deviation, range, and percentiles

Question 16

What does standard deviation measure?

Answer 16

Variability about the mean; SD is the most common measure used to describe the spread of data

Question 17

Should means or SDs be reported with ordinal data?

Answer 17

No

Question 18

By the empirical rule, what percentage of sample values are within +/- 1 standard deviation? +/- 2 SDs?

Answer 18

68% and 99%

Question 19

What is the coefficient of variation?

Answer 19

The ratio of the standard deviation to the mean; gives an idea of the spread of the data

Question 20

What are conclusions or generalizations made about a population from the study of a sample of that population?

Answer 20

Inferential statistics

Question 21

What is it called when there are two possible outcomes, the probability of obtaining either outcome is known, and you want to know the chance of observing a certain number of successes in a certain number of trials?

Answer 21

Binomial distribution

Question 22

What is it called when you are counting events in a certain period of observation, the average number of counts is known, and you want to know the likelihood of observing a various number of events?

Answer 22

Poisson distribution

Question 23

Name two types of discrete distributions

Answer 23

Binomial and Poisson