You can view which fields and filters are available in a report on the report's Columns and Filters tabs. To access these tabs, click Settings on the report itself. Or, click the icon next to the report.

If you want to compare different reports, you can use the Replicon Reports Field Matrix, available in Replicon's Documentation Archive. This document displays which fields and filters are available in each report template using a tabular format, so you can compare available settings.