BioStats Flashcards
Relative Risk Reduction (RRR)
(Risk in unexposed)-(Risk in exposed)/Risk in unexposed
ARR/Rate in the control
Number Needed to Harm (NNH)
1/Absolute Risk Increase (ARI)
Absolute Risk Increase (ARI)
ARI=Rate in treatment- Rate in the placebo
Normal Distribution
1 STD - 68%
2 STD - 95%
3 STD - 99.7%
Positive Likelihood Ratio
LR + = Sensitivity/(1-Specificity)
Negative Likelihood Ratio
LR - = (1-Sensitivity)/Specificity
Likelihood Ratio Interpretation
The higher the number, like 10, the more evidence to rule in disease
the lower the number, like <0.1, the more evidence to rule out disease
Absolute Risk Reduction (ARR)
ARR = Rate in control - Rate in the treatment
Relative Risk (RR)
Rate in the treatment/Rate in the control
Number Needed to Treat (NNT)
1/ARR
Attributable Risk Percentage (ARP)
ARP=Risk in exposed - Risk in control/Risk in exposed
(RR-1)/RR
Hazard Ratio
Rate disease/Rate in the control
False Positive Rate
1-specificity
False Negative Rate
1-Sensitivity
Odds Ratio
(A/C)/(B/D)
AD/BC