Research Terms Aka NERDS 🤓

Question 1

When reporting epidemiologic data, INCIDENCE is defined as?

Answer 1

of cases developing per unit of population per unit of time.

Question 2

What percentage of the observations in a normally distributed sample are expected to fall within a range defined as MEAN +/- 1.96 times the standard deviation?

Answer 2

+/- 1.96 = 96%

+/- 1.0 = 70%
+/- 3.0 = 99%

Question 3

What is a Crossover Study?

Answer 3

A type of clinical trial in which all participants receive the same two or more treatments, but the order in which they receive them depends on the group to which they are randomly assigned.
For example, one group is randomly assigned to receive drug A followed by drug B.

Unique in that the case serves as his/her own control and is used to investigate the transient effects of an intermittent exposure on the onset of acute outcomes.

Question 4

What is Prevalence?

Answer 4

Ratio of the number of cases to the number of non-affected individuals in a population

Question 5

What is a Cohort study?

CO-

Answer 5

2 groups - period of time

A study of two groups of patients observed over a period of time

A longitudinal study that samples a cohort (a group of people who share a defining characteristic, typically those who experienced a common event in a selected period, such as birth or graduation), performing a cross-section at intervals through time.

Question 6

Statistically Significant

Answer 6

Statistical significance is a way of mathematically proving that a certain statistic is reliable. When you make decisions based on the results of experiments that you’re running, you will want to make sure that a relationship actually exists.

It is likely not caused by chance for a given statistical significance level. Your statistical significance level reflects your risk tolerance and confidence level.

The smaller the p-value, the stronger the evidence that you should reject the null hypothesis. A p-value less than 0.05 (typically ≤ 0.05) is statistically significant. It indicates strong evidence against the null hypothesis, as there is less than a 5% probability the null is correct

Question 7

A study consists of 10 US Dental schools picked by random and then takes a random sample of 20 students within each institution.

What type of sampling is this?

Answer 7

Multistage sampling of simple random

Question 8

What is the hierarchy of evidence from strongest to weakest?

1. Expert committee of reports or opinions
2. Controlled study without randomization
3. Systemic review of randomized controlled trials
4. Randomized controlled trial

Answer 8

1. Systemic review of randomized controlled trials
2. Randomized controlled trial
3. Controlled study without randomization
4. Expert committee of reports or opinions

Question 9

Cross-Sectional Study

Answer 9

A cross-sectional study involves looking at DATA from a POPULATION at ONE specific point in TIME.
The participants in this type of study are selected based on PARTICULAR VARIABLES of interest.

DISTRIBUTION PATTERNS of sample variables

Question 10

Degree to which a research variable has nearly the same value when measured several times

Answer 10

Concordance

Question 11

What is the Pearson Correlation COefficient and what values determine what?

Answer 11

Pearson’s correlation coefficient is the test statistics that measures the statistical relationship, or association, between TWO continuous variables. … It gives information about the magnitude of the association, or correlation, as well as the direction of the relationship.

The correlation coefficient is a number between -1 and 1

-1. A perfect downhill (negative) linear relationship.
–0.70. A strong downhill (negative) linear relationship.
–0.50. A moderate downhill (negative) relationship.
–0.30. …
No linear relationship.
+0.30. …
+0.50. …
+0.70.
+1. A perfect uphill (positive) linear relationship

Question 12

Synthesizing results by combining studies?

Answer 12

Meta Analysis

Question 13

True Positive Rate

Answer 13

Sensitivity:

measures the proportion of actual positives that are correctly identified as such (e.g., the percentage of sick people who are correctly identified as having the condition)

Question 14

True Negative Rate

Answer 14

Specificity

Measures the proportion of actual negatives that are correctly identified as such (e.g., the percentage of healthy people who are correctly identified as not having the condition).

Question 15

In statistical analysis, what is correlation between two groups?

Answer 15

Direction of Relationship

Question 16

The measure most frequently used for expressing inter-examiner
reliability in a cross-sectional study is?

Answer 16

Kappa Statistic

• The kappa statistic is frequently used to test interrater reliability.
• The extent of agreement among data collectors is called “interrater reliability”
• The kappa can range from -1 to +1.
• values ≤ 0 as indicating no agreement and 0.01–0.20 as none to slight, 0.21–0.40 as fair, 0.41– 0.60 as moderate, 0.61–0.80 as substantial, and 0.81–1.00 as almost perfect agreement.

Question 17

What is Incidence?

Answer 17

Cases - Unit of population - Unit of time

A measure of the probability of occurrence of a given medical condition in a population within a specified period of time.

Although sometimes loosely expressed simply as the number of new cases during some time period, it is better expressed as a proportion or a rate with a denominator.

Question 18

The main purpose of SURVEILLANCE in public health is to?

Answer 18

DEVELOP INTERVENTION PROGRAMS

Public health surveillance provides the scientific and factual database essential to informed decision making and appropriate public health action.
The key objective of surveillance is to provide information to guide interventions.