biostatistics & pharmacoeconomics Flashcards
RR equation
risk in tx group / risk in control group
RR interpretation
RR >1 greater risk of outcome in tx
RR <1 lower risk
RR = 1 same risk
patients are AS LIKELY to have disease progression as placebo group
RRR equation and interpretation
1 - RR
LESS LIKELY to have progression
ARR equation and interpretation
(% risk in control) - (% risk in tx)
x out of every 100 patients benefit from treatment OR for every 100 patients, x fewer will have disease progression
NNT and NNH equation
1 / ARR
ROUND UP for NNT
ROUND DOWN for NNH
odds ratio equation
AD / BC
hazard ratio equation
hazard rate in tx / hazard rate in control
what is ratio data
continuous
0 = NONE
what is interval data
continuous
0 does not = NONE
what is nominal data
categorical/discrete
age, gender, mortality
what is ordinal data
categorical/discrete
pain scale, NYHA class
what type of data will have a gaussian distribution
large sample sets of continuous data
examples of independent variables
drugs, doses, placebos, patients
anything changed by the researcher
examples of dependent variables
HF progression, BP, mortality
the effect from the independent variable
CI equation
CI = 1 - alpha