Power Analysis for Survival Analysis, Exponential with Accrual & Dropouts (Sample Size Calculation)

Sample Size calculation for Survival Analysis, two-group test of equal exponential with accrual and dropouts, with options for charts of Sample Size vs. Lambda 2, vs. Alpha Level, and vs. Power.

General

Element Name Description
Lambda 1 Exponential parameter for group 1.
Lambda 2 Exponential parameter for group 2.
Accrual Period (T0) Accrual period for the sample size calculation (acceptable range 1 to 10000).
Follow-up Period (T) Follow-up period for the sample size calculation (acceptable range 1 to 10000).
Dropout Rate (D) Dropout Rate for the sample size calculation.
Power Goal Power Goal for the sample size calculation (acceptable range 0.65 to 0.999).
Alpha Level Alpha level (Type I error rate for the overall significance test) (acceptable range 0.0001 to 0.25).
Hypothesis type Null hypothesis to be tested:

 Lambda 2 = Lambda 1, (Two-tailed, null and alternative hypotheses of form - H0: Lambda2 = Lambda1, H1: Lambda2 <> Lambda1)

 Lambda 2 <= Lambda 1, (One-tailed, null and alternative hypotheses of form - H0: Lambda2 <= Lambda1, H1: Lambda2 > Lambda1)
Detail of computed results reported Output level of detail selection:

 Sample Size Calculation produces Sample Size Calculation Spreadsheet;

 Spl Size Calc plus Charts option produces, in addition, Sample Size vs. Lambda 2, Sample Size vs. Alpha Level, and Sample Size vs. Power charts.

Chart Parameters

Element Name Description
Number of Steps. (For charts only). Number of individual steps for which to calculate sample size between the starting and ending parameter values for Sample Size Charts (Min 4, Max 100).
Starting Power (For charts only). Initial power goal for calculation of Sample Size vs. Power chart.

 (Acceptable range 0.05 to 0.99).
Ending Power (For charts only). Final power goal for calculation of Sample Size vs. Power chart.

 (Acceptable range 0.10 to 0.999)
Starting Lambda 2 (For charts only). Initial Lambda 2 value for calculation of Sample Size vs. Lambda 2 chart (acceptable range 1e-010 to 0.9999).
Ending Lambda 2 (For charts only). Final Lambda 2 value for calculation of Sample Size vs. Lambda chart (acceptable range 1e-005 to 0.9999).
Starting Alpha Level (For charts only). Initial alpha level for calculation of Sample Size vs. Alpha Level chart (acceptable range 0.0001 to 0.2499).
Ending Alpha Level. (For charts only). Final alpha level for calculation of Sample Size vs. Alpha Level chart (acceptable range 0.0002 to 0.25).