EBM Day 3 Flashcards
CI=
mean+1.96(SE)
+/- 2SD
SE=
SD/sqrtN
Types of data (3)
Nominal (categroical)-yes/no, blood types
Ordinal-first second
Interval-Continous/discrete(counts)
Validity
Accuracy
2x2 of reliability vs vadlity
Precision vs accuracy
3 types of variaition
measurement-instrument/observor (inter obs)
biological-over time in 1 indiv (intra), inter-individual
voerall- measurement+biological
right skew
more data to the left
3 types of abnormal
Unusual-2 sd away from mean IF NORMALLY DIST (95th percentile), based on healthy population, some diseases less than 2sd away
Associated with Disease or Risk increase-
values of clinical variable associated with current disease or increased disease rate-continuum diseases (diabetes), most clinical values do not easily fit into normal/abnormal
Past the point where trx does more good than harm-all treatments can harm as well as heal
Sensitivity
test is positive when should be positive
-very few false negatives
TP/(TP+FN)
Specificity
test is negative when should be negative
-very few false positive
TN/(Tn+FP)
Be sensitive when
consequences of missing diagnosis is high (false neg costly)
Be specific when
consequences of confirmatory tests are serious (false positive costly)
Labeling (2 exs)
Can be positive and negative effects
You have hypertension and should take this pill
You have dementia-gg
1 attributable cause of death
suboptimal blood pressure
Normal Bp
120/80
