Item no. | Item description | Protocol | Report |
---|---|---|---|
1 | State any divergence from the conventional approach. | √ | √ |
2 | State the primary outcome (and any other outcome which the study sample size calculation is based upon), or state why there is not one. | √ | √ |
3 | Reference the formula and/or simulation approach if the standard binary, continuous or survival outcome formulas are not used [2,11]. The primary analysis should be stated in the statistical analysis section. | √ |  |
4 | State the values used for statistical parameters (such as significance level and power). | √ | √ |
5 | State the underlying basis for determining the target difference: | √ |  |
a. an important difference as judged by a stakeholder, | |||
b. a realistic difference based upon current knowledge or | |||
c. both an important and realistic difference. | |||
6 | Express the target difference according to the outcome type: | √ | √ |
a. Binary: state the target difference as an absolute and/or relative effect, along with the intervention and control group proportions. If both an absolute and a relative difference are provided, clarify if either takes primacy in terms of the sample size calculation. | |||
b. Continuous: state the target mean difference on the natural scale, the common SD and standardised effect size (mean difference/SD). It is preferable to also provide the anticipated control group mean even though it is not required for the sample size calculation. | |||
c. Time-to-event (survival): state the target difference as an absolute and/or relative difference, provide the control group event proportion, along with the intervention and control group survival distributions. Additionally, the planned length of follow-up should be stated along with the assumed accrual pattern. If both an absolute and a relative difference are provided, clarify if either takes primacy in terms of the sample size calculation. | |||
7 | Explain the choice of target difference: specify and reference any formal method used or relevant previous research. | √ |  |
8 | State the sample size based upon the assumptions specified above (for a time-to-event outcome, the number of events required should also be stated). If any factors are incorporated which alter the required sample size (such as allowance for loss-to-follow-up) they should also be specified along with the final sample size. | √ | √ |
9 | Reference the trial protocol |  | √ |