Behavioral/Biostats

Question 1

Odds ratio is used with which of study?

Answer 1

Case-control study

Question 2

Relative risk is used with which type of study?

Answer 2

Cohort study

Question 3

Describe Phase IV clinical trials?

Answer 3

Postmarketing surveillance trial of patients after approval of drug/therapy

Question 4

How is odds ratio calculated?

Answer 4

OR = (ad)/(bc)

Question 5

How is relative risk calculated?

Answer 5

Risk of developing disease in the exposed group divided by risk of developing disease in the unexposed group; RR = (a/[a+b])/(c/[c+d])

Question 6

How is relative risk reduction calculated?

Answer 6

RRR = 1-RR

Question 7

How is attributable risk calculated?

Answer 7

AR = (a/[a+b])-(c/[c+d[)

Question 8

How is absolute risk reduction calculated?

Answer 8

The difference in risk attributable to the intervention as compared to a control (e.g., if 8% of people who receive a placebo vaccine develop flu vs. 2% of those who receive a flu vaccine, then ARR = 8%-2% = 6% = 0.6)

Question 9

How is number needed to treat calculated?

Answer 9

NNT = 1/ARR

Question 10

How is number needed to harm calculated?

Answer 10

NNH = 1/AR

Question 11

What is another word for “precision” of a test?

Answer 11

Reliability - not necessarily accurate

Question 12

Does random error reduce the precision or accuracy of a test?

Answer 12

Precision

Question 13

Does systematic error reduce the precision or accuracy of a test?

Answer 13

Accuracy

Question 14

What is selection bias?

Answer 14

Nonrandom assignment to participate in a study group

Question 15

What is measurement bias?

Answer 15

Information is gathered in a way that distorts it

Question 16

What is procedure bias?

Answer 16

Subjects in different groups are not treated the same

Question 17

What is observer-expectancy bias?

Answer 17

Researcher’s belief in the efficacy of a treatment changes the outcome of that treatment (aka Pygmalion effect)

Question 18

What is Berkson bias?

Answer 18

A specific type of selection bias - looking only at inpatients

Question 19

How is standard error of the mean calculated? *standard error of the mean is an estimation of how much variability exists between the sample mean and the true population mean

Answer 19

SEM = SD/square root of n; SEM decreases as n (sample size) increases

Question 20

In Gaussian distribution, what percentage of the sample size falls within 1 SD of the mean?

Answer 20

68%

Question 21

In Gaussian distribution, what percentage of the sample size falls within 2s SD of the mean?

Answer 21

95%

Question 22

In Gaussian distribution, what percentage of the sample size falls within 3 SDs of the mean?

Answer 22

99.7%

Question 23

In positive skew distribution, list mean median and mode from greatest to largest

Answer 23

mean > median > mode

Question 24

In negative skew distribution, list mean median and mode from greatest to largest

Answer 24

mode > median > mean

Question 25

What is a Type I error?

Answer 25

Rejection of null hypothesis when in reality there is no difference

Question 26

What is a Type II error?

Answer 26

Acceptance of null hypothesis when in reality there is a difference

Question 27

When is a t-test used?

Answer 27

Checks differences between means of 2 groups.

Question 28

When is an ANOVA (analysis of variance) test used?

Answer 28

Checks differences between means of 3+ groups

Question 29

When is a chi-square test use?

Answer 29

Checks difference between 2 or more percentages or proportions of categorical outcomes (not mean values)

Question 30

What is quaternary disease prevention?

Answer 30

Identifying patients at risk of unnecessary treatment, protecting them from the harm of new interventions

Question 31

What are the four core ethical principles?

Answer 31

Respect patient autonomy, beneficence, nonmaleficence, justice

Question 32

Low birth weight is defined as what?

Question 33

What are the top three causes of death of infants under 1 year of age?

Answer 33

1. Congenital malformations 2. Preterm birth 3. SIDS

Question 34

What are the top three causes of death of children 1-14 YO?

Answer 34

1. Unintentional injury 2. Cancer 3. Homicide

Question 35

What are the top three causes of death of young adults aged 15-24?

Answer 35

1. Unintentional injury 2. Homicide 3. Suicide

Question 36

What are the top three causes of death of adults 25-34 years of age?

Answer 36

1. Unintentional injury 2. Suicide 3. Homicide

Question 37

What are the top three causes of death of adults 35-44 YO?

Answer 37

1. Unintentional injury 2. Cancer 3. Heart disease

Question 38

What are the top three causes of death of adults 45-64 YO?

Answer 38

1. Cancer 2. Heart disease 3. Unintentional injury

Question 39

What are the top three causes of death of adults over 65 YO?

Answer 39

1. Heart disease 2. Cancer 3. Chronic respiratory

Question 40

What is a crossover study?

Answer 40

Subjects are randomly allocated to a sequence of 2 or more treatments given consecutively, with a washout period.

Question 41

What is a "sentinel" event?

Answer 41

An unexpected occurrence involving death or serious physical or psychological injury that requires immediate investigation