Equivalence Test for 2x2 Crossover Designoverview how to example data see also
Equivalence Test for 2x2 Crossover DesignStat > Equivalence Tests > 2x2 Crossover Design
Use to evaluate the data from a 2x2 crossover design and determine whether the effects of a test drug are equivalent to the effects of a reference drug. For example, you can determine whether the rate of absorption for a new generic pill is equivalent to that of well-established medication.
You can also evaluate whether the test mean is greater than or less than the reference mean.
Data for two sequences are unstacked
Treatment order for sequence 1: Indicate the order of the treatments for Sequence 1.
Response: In each box, enter the column that contains the data for the appropriate period and sequence. For example, in Sequence 1, Period 1, enter the column that contains the data for Period 1 of Sequence 1.
Data for two sequences are stacked
Sequence ID: Enter the column that identifies which sequence each row belongs to.
Response from period 1: Enter the column that contains the data from Period 1.
Response from period 2: Enter the column that contains the data from Period 2.
Treatment order for sequence: Enter the ID value for the sequence that received the reference treatment in Period 1.
Test mean - reference mean: Choose to specify your equivalence criteria in terms of the difference between the test mean and the reference mean.
What do you want to determine? (Alternative hypothesis)
Lower limit < test mean - reference mean < upper limit: Test whether the difference between the means is within the limits that you specify.
Lower limit: Specify the lowest value for the difference that you consider functionally equivalent (for example, -0.2).
Upper limit: Specify the highest value for the difference that you consider functionally equivalent (for example, 0.2).
Multiply by reference mean: Check to specify that the limit represents a proportion of the reference mean. For example, check to specify the limit as 0.2 multiplied by the mean Tmax for the reference sample, rather than as the fixed value of 0.2 hours.
Test mean > reference mean: Test whether the test mean is greater than the reference mean.
Test mean < reference mean: Test whether the test mean is less than the reference mean.
Test mean - reference mean > lower limit: Test whether the test mean is greater than the reference mean by a specific amount. For example, you can test whether the mean Tmax for the test population is at least 0.2 hours greater than the Tmax for the reference population.
Lower limit: Specify the difference to test (for example, 0.2).
Multiply by reference mean: Check to specify that the limit represents a proportion of the reference mean. For example, check to specify the limit as 0.2 multiplied by the mean Tmax for the reference sample, rather than as the fixed value of 0.2 hours.
Test mean - reference mean < upper limit: Test whether the test mean is less than the reference mean by a specific amount. For example, you can test whether the mean Tmax for the test population is at least 0.2 hours less than the Tmax for the reference population.
Upper limit: Specify the difference to test (for example, -0.2).
Multiply by reference mean: Check to specify that the limit represents a proportion of the reference mean. For example, check to specify the limit as 0.2 multiplied by the mean Tmax for the reference sample, rather than as the fixed value of 0.2 hours.
Test mean / reference mean: Choose to specify your equivalence criteria in terms of the ratio of the test mean to the reference mean.
What do you want to determine? (Alternative hypothesis)
Lower limit < test mean / reference mean < upper limit: Test whether the ratio of the test mean to the reference mean is within the limits that you specify. Both limits must be greater than zero. A ratio of 1 indicates that the two means are equal.
Lower limit: Specify the smallest ratio that you consider equivalent (for example, 0.9). The limit must be greater than zero.
Upper limit: Specify the largest ratio that you consider equivalent (for example, 1.1). The limit must be greater than zero.
Test mean / reference mean > lower limit: Test whether the ratio of the test mean to the reference mean is larger than the limit that you specify. For example, you can test whether the mean of the test population is at least twice as large as the mean of the reference population.
Lower limit: Specify the ratio to test (for example, 2). The limit must be greater than zero.
Test mean / reference mean < upper limit: Test whether the ratio of the test mean to the reference mean is smaller than the limit that you specify. For example, you can test whether the mean of the test population is, at most, half as large as the mean of the reference population.
Upper limit: Specify the ratio to test (for example, 0.5). The limit must be greater than zero.
Test mean / reference mean (by log transformation): (This option is not available for summarized data.) Choose to specify your equivalence criteria in terms of the ratio of the test mean to the reference mean, as modeled with a log transformation of the original data. For this option, all observations must be greater than zero.
What do you want to determine? (Alternative hypothesis)
Lower limit < test mean / reference mean < upper limit: Test whether the ratio of the test mean to the reference mean is within the limits that you specify. Both limits must be greater than zero. A ratio of 1 indicates that the two means are equal.
Lower limit: Specify the smallest ratio that you consider equivalent (for example, 0.9). The limit must be greater than zero.
Upper limit: Specify the largest ratio that you consider equivalent (for example, 1.1). The limit must be greater than zero.
Test mean / reference mean > lower limit: Test whether the ratio of the test mean to the reference mean is larger than the limit that you specify. For example, you can test whether the mean of the test population is at least twice as large as the mean of the reference population.
Lower limit: Specify the ratio to test (for example, 2). The limit must be greater than zero.
Test mean / reference mean < upper limit: Test whether the ratio of the test mean to the reference mean is smaller than the limit that you specify. For example, you can test whether the mean of the test population is, at most, half as large as the mean of the reference population.
Upper limit: Specify the ratio to test (for example, 0.5). The limit must be greater than zero.