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- Select the type of calculation. You may choose either to enter hazard rates(default) or survial proportions.
- Select the type of input. You may choose either to calculate power (default) or total sample size.
- Enter the number of strata(default is 1). If you have changed any of the defaults for
type of calculation, type of input, or number of strata, press
*Change types or strata*to configure the remainder of the inputs. - Boxes with a yellow background are for your input. Boxes with a blue background are
calculated by the program. Boxes with a red background do not apply to this type of
calculation.
- If you are calculating power, enter an accrual rate. Values in the power text box are ignored.
- Likewise, if you are calculating accrual rate, a value in the accrual rate text box is ignored. Enter a power in the power text box.

- Select test type: Choose either to make a one-sided (default) or two-side test.
- Enter values for years of accrual, years follow-up, proportion in standard group, and alpha (default .05). These years must be nonnegative and proportions in the closed interval [0,1].
- Enter values for hazard rate, standard; hazard ratio, proportion surviving, and survival time entries as indicated, according to your type of calculation.
- If number of strata is greater than 1, then enter proportion for each strata except the last one which is calculated for you.
- Do not use comma separators for numbers (eg. enter '1000', not '1,000').
- Press the
*Calculate*button to make the calculations.