When to avoid using the Scope feature

Whilst it can be tempting to apply Scope criteria in most cohort definitions, it should be pointed out that this is often not needed. For example, if you wished to report upon admissions to Hospital A during 2014 there is no need to restrict your cohort by setting the following Scope filters within the cohort definition:

• Hospital = A
• Date range = 1st Jan 2014 - 31st December 2014

This is because during report creation you have several options when selecting the data to be included in the report. At that stage you can limit the report to admissions to Hospital A in 2014.

Furthermore, if you include Hospital A in the cohort definition then, unless you also select Hospital A as the sole data source during report creation, you could easily end up creating a report that covers data pertaining to admissions to Hospital B as well as Hospital A (patients in your cohort who were admitted to Hospital A in 2014 may also have other data recorded about admissions to Hospital B, which could be included in the report output if you don’t actively exclude it).