# EBM Exam 1

 The flashcards below were created by user Rx2013 on FreezingBlue Flashcards. Type of data in non-parametric tests nominalordinal Nominal data mutually exclusiveyes/nomale/female Chi squared test two samplesat least 40 observations (20 per group)nominal data Fisher's Exact similar to chi squared but for smaller sample sizestwo groupsless than 5 per groupusually for uncommon eventsfor nominal data Mantel-Haenszel three or more groupsseries of chi-squarestotals are added up and overall chi-square is calculatedfor nominal data McNemar's Test similar to chi-squareddata is paired (there is a control or pt serves as their own control)for nominal data Ordinal Data categoricalranked on a scale with no consistent distance between valuesex. pain scale Mann-Whitney U/Wilcoxon Rank Sum two groupsranks individual observations rather than valuesdata values are assigned from lowest to highestthe sum of the data is totalled at the bottem fo the chart(rank pain 1-6 and the group with lower number has better pain control) Kruskal-Wallis for observational datafor multiple comparisonsif average ranks are close H0 is not rejectedpost hock analysis needed to determine difference between treatment groupsFriedman's test is similar for 3 or more groups Wilcoxon signed rank similar to paired t-testfor paired datadifferences arranged in order of absolute valueobservations of 0 are excludedaverage rank is assigned continuous data ratio or interval dataplaced on a numerical scale with infinite amount of valuesequal distance between those values T-test "student's T-test"compares the mean of a population to the known mean2 groupsvariance of both groups must be equalinterval or ratio data ANOVA for interval or ratio data3 or more groups ANCOVA for ordinal or ratio datasimilar to ANOVA but controls for covariates ex. study effect of bisphosphonates on osteoprosis, but age and exercise are also factors, control for these to see the difference the drug makes Paired T-test for interval or ratio datacompare the mean difference between 2 groups that are paired or matchedcan be used when the subject is their own control (cross over) ANOVA for repeated measures similar to ANOVA but measures subjects under a different set of conditions in a repeated mannerex. pt with osteoporosis screened anually for next 5 years for changes in BMD correlation measure of association between 2 variablesr ranges from -1 to 1independant variable is xdependent variable is y regression 0.9-1 = excellent correlation, probably predictive0.7-0.9 = good correlation, may be predictive0.6-0.7 = good correlation, may not be predictive<0.6 considered not predictive Kaplan Meier survival analysis survival analysis as a function of timeinterval or ratio data time on the x axis Survivial analysis censored vs. uncensored censored means incomplete data, but is analagous to intent-to-treat Post-Hoc Analyses performed after primary analysis when H0 has been rejectedconsidered inferior to planned comparisonsoften easier to understand AuthorRx2013 ID132680 Card SetEBM Exam 1 DescriptionBiostats 3 Updated2012-02-03T22:35:17Z Show Answers