Statement:
The level of criminal activities is lower in Oman than in Costa Rica

In the The Most Criminal Countries rating Oman holds position #133 ²⁰²² out of 139 and Costa Rica is #43 out of 139 ²⁰²².
Position of Oman is better than position of Costa Rica.
Oman is an outsider of the "The Most Criminal Countries" rating. So in most cases, you can feel safe and unlikely will face a criminal, compared to Costa Rica

Referencies:

1. The Most Criminal Countries ²⁰²² by Numbeo

   The countries in the rating sorted by 'Crime Index' in descending order.

   Costa Rica	'Crime Index' value is	53.86
   Oman	'Crime Index' value is	19.72