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When carrying out tests for proportions what makes them valid in a one sample test?

when r>5 and (n-r)>5 where r is the number in the sample with the characteristic of interest


In a two-sample test of proportion what is necessary to make it valid?

r1, R2, (n1-r1) and (n2-r2) are all >5


What is the simplest approach of carrying out a test of association?

Chi-squared test


What is the Chi-squared test?

X2 = sigma (obs-exp)2/exp


What are the assumptions for a Chi-squared test?

observations are from independent subjects or experimental units
The expected values are not too small as a rough rule, no more than 20% of the expected values should be <5 and none should be <1


What test should be used instead of a Chi-squared test if the variables are ordered?

Chi square test for trend (trend needs to be linear to be appropriate)


In the case of a 2X2 table, what test should be carried out when the values of interest are very small?

Chi squared test with continuity correction (conservative) or Fisher's exact test


What tests can be used for comparisons of proportions from paired samples?

Paired confidence interval
McNemar's test


What test should be used for 1 variable with 2 categories?

1 proportion CI and test


What test should be used in a 2x2 table?

2 proportion CI and test
Chi-squared test of association
Chi-squared test of association with continuity correction
Fishers exact test


What test should be used in >2x>2 table

Chi-squared test of association
Chi-squared test for trend( if categories ordered)
or collapse rows and/or columns to 2x2


What test should be used for paired data?

McNemars or CI for paired data