Please answer the questions below regarding the details of your study. Upon answering all the questions, the form will generate the required sample size for your study. If you are unsure about a particular aspect of the study design you will be using, you may select the 'unsure/undecided' option for certain questions. In these instances, a sample size will be calculated for you across all options for that particular facet, irrespective of a particular option.

All sample sizes assume a power of .8 and effect size will be displayed when providing the required sample size. Power estimates for each effect were determined using two-tailed, a-priori two group independent samples t tests. The allocation ratio was assumed equivalent for each group, and the error probability was set to 0.05 for each effect.

The effect size used to compute sample size is based on the effect sizes (adjusted for publication bias where required) as reported in Supplement 1 of Gillath, Karantzas, Romano & Karantzas (unpublished manuscript).