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Flashcards in Stats Deck (10):
1

T Test

-used to compare the difference between the means of two groups

2

Analysis of Variance

-ANOVA
-compares the difference between the means of two or more groups

3

Chi Square Test

-used to check for an association between 2 categorical variables (ie. gender and smoking status random vs. correlation)
-given as number of people for example, not mean number

4

Normal Distribution Rule

68/95/99

68% within -1 and +1 standard deviations, etc.

5

Hawthorne Effect

Subjects change their behavior once they realize they are being studied.

6

Alpha

-probability of rejecting null hypothesis when null hypothesis is true
-related to type 1 error (you are pregnant to a dude)

7

Beta

-probability of failing to reject null hypothesis when null hypothesis is false
-type 2 error (you are not pregnant to pregnant lady)
-1-B = power (how many people needed to find significant difference)

8

Case Series

-medical research that tracks subjects with known exposure
-no control necessarily

9

How to Find Number Needed to Harm/Treat

-calculate absolute risk difference between treatment and placebo
-NNH or T = 1/absolute risk difference

10

Effect Modification

-when the effect of the main exposure on the outcome is modified by another variable
-not bias or confounding
-significant difference with stratification (not so with confounding)