Appraising Dx Research studies

Question 1

Variables are categorical with no order and example

Answer 1

Nominal

Gender

Question 2

Variables are in ordered Category and example

Answer 2

Ordinal

MMT

Question 3

Variables are ordered precisely and continously
Has true 0

example?

Answer 3

Ratio

Muscle strength test

Question 4

Variables are ordered precisely and continously has no true 0

Example

Answer 4

Interval

Temperature

Question 5

Dx study includes

Answer 5

Pt. History
Systems review
Informed use of test and measures

Question 6

Distinguish between people who have movement disorder and those who dont

Answer 6

Dx test.

Question 7

Range of scores that captures individuals w/o mvt disorders

Answer 7

Reference interval

Question 8

Individuals with mvt disorder fall where in reference interval

Answer 8

Outside

Question 9

Most comon design for development of Dx test

Answer 9

Cohort

Question 10

▪ Forward planning to collect data on both the clinical test (index test) under study and a gold standard comparison test

Answer 10

Prospective study

Question 11

Looks back at previously collected findings and examines exposures to suspected risk or protection factors in relation to an outcome that is established at the start of the study

Answer 11

Retrospective

Question 12

Which study has possible risk for bias

Answer 12

Retrospective

Question 13

Masked application of both tests means that you require

Answer 13

At least 2 examiners completing only 1 of the tests

Question 14

Pt definitely has condition

Answer 14

True +

Question 15

Pt def doesnt have condition

Answer 15

True -

Question 16

Doesnt have condition with gold standard, but + with clinical test

Answer 16

False +

Question 17

Test positive on gold standard

Negative on clinical test

Answer 17

False -

Question 18

Tests accuracy in correctly identifying presence of problem

Answer 18

Sensitivity

Question 19

True positive rate ratio

Answer 19

Sensitivity

A/a+c

Question 20

False negative rate

Answer 20

1-sensitivity

Question 21

Tests ability to correctly identify absence of problem

Answer 21

Specificity

Question 22

True negative Rate

Answer 22

Specificity

D/b+d

Question 23

False positive rater

Answer 23

1- specificity

Question 24

SpPin

Answer 24

High specificity, + test rules in Dx

Question 25

SnNout

Answer 25

High sensitivity, - result rules out Dx

Question 26

Plot of specificity and sensitivity values generated from a series of cutpoints in Dx test

Answer 26

Receiver operating Characteristic ROC curve

Question 27

Used to determine optimal cutoff threshold in Dx test

Answer 27

ROC curve

Question 28

Represent trade off b/w TPR and FPR

Answer 28

ROC curve

Question 29

Likelihood a person testing positive actually has disease

Answer 29

Positive predictive value

Question 30

PPV equation

Answer 30

A/a+b

Question 31

Likelihood person testing negative is disease-free

Answer 31

Negative predictive Value

Question 32

NPV equation

Answer 32

D/d+c

Question 33

The probability of the target disorder before a diagnostic test result is known (i.e. the prevalence of a disease).

Answer 33

Pre-test Probability

Question 34

When pre-test probability is VERY low

Answer 34

Disease is unlikely and test not needed

Question 35

o When pre-test probability is VERY high,

Answer 35

Disease is likely and test may not be needed

Question 36

Pre-test probability in midrange

Answer 36

May be worth pursuing

Question 37

probability of a disease based on the outcome of a test.

Answer 37

Post-test probability

Question 38

High Post test probability Low? Midrange??

Answer 38

Confirms Dx Rule out Dx More testing needed

Question 39

Aids in determining post test probability

Answer 39

Likelihood ratios

Question 40

how much more likely a positive test will be seen in someone with the disorder than someone without the disorder

Answer 40

LR+

Question 41

LR+ equation

Answer 41

Sensitivity/1-specificity

Question 42

Large LR+ rules a disease

Answer 42

IN

Question 43

how much more likely a negative test will be seen in those with the disorder than in those without the disorder

Answer 43

Negative Likelihood ratio LR-

Question 44

LR- equation

Answer 44

1-sensitivity/specificity

Question 45

Low LR- rules disease

Answer 45

OUT

Question 46

plot of both pre-test positive and negative likelihood ratios to visualize and quantify post-test probabilities

Answer 46

nomogram

Question 47

Large LR+ Mod Small Negligible

Answer 47

>10 5-10 2-5 <2

Question 48

Large LR- Mod Small Negligible