intro to biostats

Question 1

required assumptions of interval data

Answer 1

normally distributed
equal variances
randomly derived and independent

Question 2

what test can be used to determine equal variance in interval data

Answer 2

levene’s test

Question 3

handling interval data not normally distributed

Answer 3

use non parametric tests

or transform data to standardized value (z score or log)

Question 4

if stem has prediction then what comparisson

Answer 4

regression

Question 5

occurences over time

Answer 5

survival comparison

Question 6

are there differneces btwn to categories

Answer 6

group comparison

Question 7

will say want correlation

Answer 7

correlation

Question 8

nominal correlation test

Answer 8

contingency coefficient

Question 9

ordinal correlation tewst

Answer 9

spearman correlation

Question 10

interval correlation test

Answer 10

pearson correlation

Question 11

special thing about pearson correlation

Answer 11

just assesses for linear correlation, may still be non linear correlations if pearson is non significant

Question 12

what is surivaval tests usually represented by

Answer 12

kaplan meier curve

Question 13

nominal survival
ordinal survival
interval survival

Answer 13

how do you survive?

Long Cox Kill

log rank
cox proportinal hazards test
kaplan meier test

Question 14

nominal regression
ordinal regression
interval regression

Answer 14

Logs multiply linearlly

logistic regression
multinomaial logistic regression
linear regression

Question 15

nominal, 3 groups or more and related

Answer 15

cochran

johnny cochran has worked for 3 or more seperate normal clients

Question 16

nominal 3 groups or more and independent

Answer 16

chi sqauare and fisher exact

cameron fiser nominally has 3 independent crews working for him

Question 17

nominal, 2 groups, related

Answer 17

mcnemar

Question 18

nominal, 2 groups, independent

Answer 18

(pearsons) chi square and fisher’s exact

cam fiser with 2 independent crews

Question 19

follow up confirmation test for nominal

Answer 19

bonferroni test of inequality

normal bon fire

Question 20

ordinal, 3 groups or more, related

Answer 20

friedman

ordinarily 3 related groups are free

Question 21

ordinal, 3 groups or more, independent

Answer 21

kruskal-wallis

krush the wall

Question 22

ordinal, 2 groups, independent

Answer 22

whitney is ordinary, independent of mann

mann whitney

Question 23

ordinal, 2 groups, related

Answer 23

wilcoxon signed rank

mrs wilcox signed rank
she is ordinary and want to be related

Question 24

follow up test ordinal for 3 groups or more

Answer 24

student newman keul
dunnett
dunn

Question 25

nominal, 2 groups or more with expected cell count under 5

Answer 25

fisher’s exact test

Question 26

follow up test interval 3 or more groups

Answer 26

student newman keul
dunett
dunn
tukey or scheffe
bonferroni

Question 27

a correlation test showing relationship or agreement between evaluator (consistency of decisions, determinations)

Answer 27

kappa statistic

Question 28

kappa interpretation

Answer 28

+1 = observers perfectly classify everyone exact same way

0 = no relationship between observers

-1 = boservers classify everyone exact opposite

Question 29

null hypothesis

Answer 29

no true diff btwn groups of comparison

Question 30

type 1 error

Answer 30

rejecting null hypothesis when shouldnt

Question 31

type 2 error

Answer 31

not rejecting null hypothesis when you should

Question 32

the ability of a study design to detect a true difference if one truly exists btwn group comparisons, and therefore the level of accuaracy in correctly accepting/rejecting the null hypotheis

Answer 32

power (1-B error)

Question 33

what increases the power

Answer 33

increasing the sample size

Question 34

interpretation of p value

4

Answer 34

probability of making type 1 error

probability of claiming diff btwn groups when one doesn’t really exist

probability of obtaining group diff as great or greater if the groups were actually same/equal

probability of obtaining a test statisti as high/higher if groups were actually the same/equal

Question 35

interval 2 groups, independent

Answer 35

student t

Question 36

interval, 2 groups, related

Answer 36

paired t test