Unit 6 & 7: Evidence Based Practices

Question 1

SNOUT

Answer 1

Highly SENsitive rules OUT when NEGATIVE

Question 2

SPPIN

Answer 2

Highly SPecific rules IN when POSITIVE

Question 3

POSITIVE Liklihood Ratio (+LR)

Answer 3

measure of how well a test:
when POSITIVE rules IN
+LR = 1.0 is USELESS

Question 4

2, 5, 10 rule

Answer 4

LR 2 = FAIR = +15%
LR 5 = GOOD = +30%
LR 10 = EXCELLENT = +45%

Question 5

NEGATIVE Liklihood Ratio

-LR

Answer 5

measures how well a test when NEGATIVE rules the condition OUT
-LR = 1.0 USELESS

Question 6

KAPPA (K)

Answer 6

measure of test reproducibility BEYOND CHANCE ALONE between INDEPENDENT examiners (not within the same examiner)

Question 7

Acceptable Kappa reliability

Answer 7

greater or equal to 60%

Question 8

Sensitivity + Specificity = 100%

Answer 8

completely USELESS

Question 9

The Reciprocal (-LR)

Answer 9

0. 5 recip of 2 Good -15% from prevalence
1. 2 recip of 5 Fair -30%
2. 1 recip of 10 Excellent -45%

-LR = 1.0 is completely useless

Question 10

Standard Mean Difference (SMD)

Answer 10

raw difference between AVERAGE scores in the treatment group & control group

raw difference between average scores at beginning of RCT and end of RCT WITHIN the SAME GROUP

typically a negative number

Question 11

When is Standard Mean Difference (SMD) statistically SIGNIFICANT

Answer 11

p < 0.05, then statistically SIGNIFICANT

LESS THAN

Question 12

Relative Risk (RR)
definition

Answer 12

Chance of OUTCOME occurring in the treatment group/chance of it happening in control group

OR treatment/control

Question 13

Odds Ratio (OR)
definition

Answer 13

Chance of EVENT occurring in the treatment group/chance of same thing happening in the control group

Question 14

Relative Risk GREATER than 1.0

Answer 14

RR > 1.0 = GREATER chance of outcome occurring in TREATMENT group compared to control group

Question 15

Relative Risk LESS than 1.0

Answer 15

RR < 1.0 = REDUCED chance of outcome occurring in the TREATMENT group compared to the control group

Question 16

Relative Risk = 1.0

Answer 16

RR = 1.0: NO DIFFERENCE in chance of outcome occurring in either treatment or control group. the treatment is USELESS!

Question 17

Odds Ratio GREATER than 1.0

Answer 17

OR > 1.0 = odds of event occurring in TREATMENT group is GREATER than same event in the control group

Question 18

Odds Ratio LESS than 1.0

Answer 18

OR < 1.0 = odds of event occurring in TREATMENT group is LESS than same event in control group.

Question 19

Odds Ratio = 1.0

Answer 19

OR = 1.0: NO DIFFERENCE in odds of event occurring in treatment and control group

Question 20

2 Ways to Determine Statistical Significance

Answer 20

P-Value and Confidence Intervals (CI)

Question 21

P-Value

Answer 21

measure of the probability that a result is PURELY due to CHANCE

(only implies the presence or absence of statistical significance)

Question 22

Statistically significant/insignificant P-values

Answer 22

statistically significant <0.05

statistically insignificant >0.05

Question 23

Confidence Intervals (CI)

Answer 23

An estimate of the RANGE OF VALUES that are likely to include the result of the study

Question 24

The Narrower the CI…

Answer 24

The narrower the CI,
the more PRESCICE the point estimate is
the LARGER the RCT

thus, the SMALLER the trial, the WIDER the confidence interval, the LESS confidence

the LARGER the trial, the NARROWER the interval, the MORE confidence