EBCP

Question 1

Incidence x duration

Answer 1

Prevalence

Question 2

Incidence

Answer 2

of new cases in population at risk/unit time

Question 3

Prevalence = incidence

Answer 3

Acute diseases

Question 4

Prevalence > incidence

Answer 4

Chronic diseases

Question 5

Quantitative measurement of disease

Answer 5

Morbidity

Question 6

Quantitative measure of death

Answer 6

Mortality

Question 7

Probability of developing a disease/complication within a given time interval

Answer 7

Risk

Question 8

A variable or exposure that decreases the probability of developing a disease

Answer 8

Protective factor

Question 9

Ratio of incidence rates in two groups being compared

Answer 9

Relative Risk (RR)

Question 10

Relative Risk =

Answer 10

incidence of exposed group/incidence of non-exposed group

Question 11

RR = 1

Answer 11

No difference in risk

Question 12

RR > 1

Answer 12

factor increases risk

Question 13

RR<1

Answer 13

Factor decreases risk

Question 14

Looks for associations within a population at one point in time

Answer 14

Cross-sectional study

Question 15

Estimates prevalence, but not incidence

Answer 15

Cross-sectional study

Question 16

Uses odds ratio (OR)

Answer 16

Cross-sectional study, Case control

Question 17

Starts with groups with a specified outcome and looks at associated exposures

Answer 17

Case control

Question 18

Always retrospective

Answer 18

Case control

Question 19

Starts with groups of specified exposure and looks at associated outcome

Answer 19

Cohort

Question 20

May be retrospective or prospective

Answer 20

Cohort

Question 21

Uses relative risk ratio

Answer 21

Cohort

Question 22

Error that randomly varies from one measurement to another

Answer 22

Random errors: not accurate, not reliable

Question 23

Error that does not randomly vary, but moves measurements systematically away from their true value (bias)

Answer 23

Systematic errors: reliable but not accurate

Question 24

Precision. Data is reproducible. Related to random error.

Answer 24

Reliability

Question 25

Accuracy. Related to systemic error.

Answer 25

Validity

Question 26

Categorical variables

Answer 26

Place individuals into groups. Described using % or proportions

Question 27

Ordinal

Answer 27

Categorical variable: low, moderate, high

Question 28

Nominal

Answer 28

Categorical variable: have names, no order

Question 29

Dichotomous

Answer 29

Categorical variable: exactly 2 categories: yes or no

Question 30

Continuous variables

Answer 30

Described using measures of central tendency (mean, median, mode) and measures of variability (standard deviation/error) Have numerical values for which arithmetic operations

Question 31

Normal distribution

Answer 31

Mean = median = mode: mean is good measure of clinical tendencies

Question 32

Right skew

Answer 32

mean > median > mode: median is good measure of clinical tendencies

Question 33

Left skew

Answer 33

mean < median < mode: median is good measure of clinical tendencies

Question 34

Bimodal distribution

Answer 34

Distribution with two peaks: modes are good measures of central tendency

Question 35

Standard error

Answer 35

SD/sqrt(n). Accounts for reliability of measurement.

Question 36

Assess statistical difference across groups

Answer 36

Chi-square

Question 37

Assess statistical difference across small groups

Answer 37

Fisher's exact test

Question 38

Comparing 2 groups, if groups have normal distribution (uses means)

Answer 38

T-test

Question 39

Comparing 2 groups that do NOT have normal distribution (compares medians)

Answer 39

Wilcoxon-Mann-Whitney

Question 40

Comparing 3 or more groups, does not require normal distributions

Answer 40

ANOVA

Question 41

Type 1 Error

Answer 41

Identify difference between the groups when one does not exist: Rejecting a null hypothesis in favor or alternative when NULL is actually TRUE

Question 42

Type 2 Error

Answer 42

Data fails to identify a difference between groups when one exists: Failing to reject the null hypothesis when the NULL is FALSE

Question 43

P-value

Answer 43

Probability that difference between groups is due to chance alone. P-value < 0.05 = reject null hypothesis, significant

Question 44

Alpha

Answer 44

Probability of committing a type 1 error.

Question 45

Beta

Answer 45

Probability of committing a type 2 error. Beta = 0.10 or 0.20

Question 46

Power

Answer 46

= 1 - beta. Probability of finding a difference between groups when a difference does exist = probability of rejecting the null hypothesis it is false

Question 47

If CI excludes 0, we can reject null hypothesis when null hypothesis =

Answer 47

Mean 1 = Mean 2. Alternative hypothesis: Mean 1 =/= Mean 2

Question 48

If CI excludes 1.00, we can reject the null hypothesis when null hypothesis =

Answer 48

RR=1, Proportion 1 = Proportion 2, Alternative hypothesis: RR =/= 1