Statistic Terms

Question 1

Clinical significance

Answer 1

The practical importance of a treatment effect—whether it has a real, genuine, palpable, noticeable effect on daily life. It was originally anchored to the patient’s perception but has since expanded beyond this boundary.

Question 2

Clinical trial

Answer 2

Any research study that prospectively assigns human participants or groups of humans to one or more health-related interventions to evaluate the effects on health outcomes. Clinical trials are divided into four phases which are designed to keep patients safe and to answer dedicated questions about the eficacy or effectiveness of an intervention.

Question 3

Confidence intervals

Answer 3

A range of values so deined that there is a speciied probability that the value of a parameter lies within it.

Question 4

Data

Answer 4

Recorded factual material commonly retained by and accepted in the scientiic community as necessary to validate research indings.

Question 5

Effect Size

Answer 5

This is the magnitude of an intervention relected by an index value. It can be calculated from the data in a clinical trial and is mostly independent of sample size. Most interventions have small to moderate effect sizes.

Question 6

Effectiveness

Answer 6

The performance of an intervention under “real-world” circumstances.

Question 7

Efficacy

Answer 7

The performance of an intervention under ideal and controlled circumstances.

Question 8

False negative

Answer 8

A test result which incorrectly indicates that a particular condition or attribute is absent.

Question 9

False Positive

Answer 9

A test result which incorrectly indicates that a particular condition is present.

Question 10

Fidelity

Answer 10

This is described two ways. The extent to which delivery of an intervention adheres to the protocol or program model originally developed and how close the intervention relects the appropriateness of the care that should be provided.

Question 11

Implementation Science

Answer 11

The science of putting (executing) a project or a research inding into effect.

Question 12

Methodology

Answer 12

Within the research domain, this relects the speciic procedures or techniques used to identify, select, process, and analyze information about a research topic.

Question 13

Minimally clinically important difference

Answer 13

The smallest difference in score in the domain of interest which patients perceive as beneicial and which would mandate, in the absence of troublesome side effects and excessive cost, a change in the patient’s management.

Question 14

Outcomes research

Answer 14

A broad umbrella term without a consistent de nition. However it tends to describe research that is concerned with the effectiveness of public-health interventions and health services.

Question 15

P value

Answer 15

The probability, under an assumption of no difference in groups of obtaining a result equal to or more extreme than what was actually observed. Usually depicted at 5%.

Question 16

Personalized medicine

Answer 16

Within research, this involves the study of tailoring of medical treatment to the individual characteristics of each patient.

Question 17

Precision medicine

Answer 17

A form of medicine that uses information about a person’s genes, proteins, and environment to prevent, diagnose, and treat disease.

Question 18

Reliability

Answer 18

This is measured in several ways. It is the degree to which the result of a measurement, calculation, or speciication can be depended on to be precise.

Question 19

Statistical assumptions

Answer 19

Characteristics about the data that need to be present before performing selected types of inferential statistics.

Question 20

Statistical significance

Answer 20

Refers to the claim that a result from data generated by testing or experimentation is not likely to occur randomly or by chance, but is instead likely to be attributable to a speciic cause.

Question 21

Statistics

Answer 21

The practice or science of collecting and analyzing numerical data in large quantities, especially for the purpose of inferring proportions in a whole from those in a representative sample.

Question 22

True negative

Answer 22

A test result that accurately indicates a condition is absent.

Question 23

True positive

Answer 23

A test result that accurately indicates a condition is present.

Question 24

Variable

Answer 24

A variable, or data item, is any characteristic, number, or quantity that can be measured or counted.

Question 25

Validity

Answer 25

The extent that the instrument measures what it was designed to measure. There are multiple types of validity, each representing a different construct.

Question 26

Nominal

Answer 26

Two categories, such as “yes or no”, boy or girl

Question 27

Ordinal

Answer 27

Has order but not rank. Such as strongly agree, agree, disagree, and strongly disagree

Question 28

Interval

Answer 28

Has rank and order. 1-4, 5-8, 9-12, etc.

Question 29

Ratio

Answer 29

Has rank, order, and is countable. Examples include weight, temperature, or age.

Question 30

Parametric versus non parametric

Answer 30

Parametric tests are used when data are normally distributed. Nonparametric tests are also called distribution-free tests because they don’t assume that your data follow a speciic distribution. They also can be used with smaller sample sizes, and when you want to be more conservative with your analyses. Parametric analyses test group means, whereas, nonparametric analyses test group medians.

Question 31

Sensitivity

Answer 31

The proportion by percentage of patients who have the disease of interest who register a positive test inding

Question 32

Specificity

Answer 32

The proportion by percentage of patients who do not have the disease of interest who register a negative test inding

Question 33

Positive predictive value

Answer 33

Positive predictive value is the probability that subjects with a positive screening test truly have the disease

Question 34

Negative predictive value

Answer 34

Negative predictive value is the probability that subjects with a negative screening test truly don’t have the disease

Question 35

Positive likelihood ratio

Answer 35

A positive likelihood ratio (LR+) relects the probability of a patient with the disease and a positive test divided by the probability of a patient without the disease and a positive test. It is commonly used to rule in a condition.

Question 36

Negative likelihood ratio

Answer 36

A negative likelihood ratio (LR-) is the probability of a person who has the disease testing negative divided by the probability of a person who does not have the disease testing negative. It is commonly used to rule out a condition.

Question 37

Accuracy

Answer 37

The accuracy of a test can be calculated by examining the proportion of true positive and true negative in all evaluated cases. Accuracy=TP+TN / TP+TN+FP+FN

Question 38

Type 1 error

Answer 38

A type 1 error is also known as a false positive and occurs when a researcher incorrectly rejects a true null hypothesis. This means that your report that your findings are significant when in fact they have occurred by chance.

Question 39

Type 2 error

Answer 39

A type II error is also known as a false negative and occurs when a researcher fails to reject a null hypothesis which is really false. Here a researcher concludes there is not a significant effect, when actually there really is.

Question 40

Norm referenced

Answer 40

Standard point scores
Compares individual performance with group performance
Normal distribution of scores desired
Maximizes differences among individuals
Requires diagnostic skills of the examiner
May not be sensitive to effects of therapy or instruction
Not concerned with task analysis
Summative

Question 41

Criterion referenced

Answer 41

Cutoff scores
Compares performance with described criteria
Variability of scores not obtained, mastery of skills desired
Discriminates between successive performances of one individual
Provides information to plan therapy/instruction
May be sensitive to effects of intervention
Depends on task analysis
Formative

Question 42

Construct validity

Answer 42

is the measure accurately representing the trait to be studied

Question 43

Concurrent validity

Answer 43

two tests administered at the same time to determine correlation

Question 44

Criterion related validity

Answer 44

the degree to which the characteristic in question correlates with other indicators or criterion measures

Question 45

Content validity

Answer 45

relationship between test items or rating and the definition of the construct to be tested

Question 46

Predictive validity

Answer 46

correlation between one measure taken at a particular time to another measure taken at some future time

Question 47

Responsiveness

Answer 47

ability to measure to detect a clinical change. Depends on sensitivity to change

Question 48

Standard error of measurement

Answer 48

Function of a test’s reliability. Measures how much a child’s observed score is expected to vary even when the child doesn’t change: 95% of scores will fall +/-2 standard errors.

Question 49

Confidence interval

Answer 49

Gives range within which 95% of a test score will fall. Usually use 90 or 95%

Question 50

Minimum detectable change

Answer 50

Smallest difference in scores that would be greater than by change alone. Important for determining change over time or with specific intervention.

Question 51

Item response theory

Answer 51

methods of constructing tests that differentiate the difficulty of items and how well the items can detect differences among subgrounds

Question 52

Rasch analysis

Answer 52

one type of IRT. These methods test the reliability, validity, and item difficulty with individuals from subgroups such as children with disabilities.