This form allows you to enter important sample information that will help you calculate your performance metrics. Ripple is very flexible and thus allows you to define very specific study samples with multiple combinations of demographic variables, such as defining multiple age ranges or unique age or sex distributions per custom groups. Yet, the default variables will be enough for most studies. So if you see something that does not apply to you, simply leave it blank.
An important section of this form is the Custom Categories section. Here you will be able to create categories and their subgroups that are critical to your study sample and enrollment. For example, you may need to track enrollment among participants assigned to a treatment vs. a control group, smokers vs. non-smokers, etc.