Studies like these can be overwhelming at first glance. Here are two helpful tips:
1. When trying to determine if it's empirical...
Look for the methodology and results section first. These sections will help you determine if the research is original to the author(s). If it's empirical, there will be very few to no in-text citations in these sections.
2. When reading for content...
Think of it like a sandwich and consume the outside bread first - the introduction and conclusion. This will give you a good overview before diving in to the deeper, meatier content in the middle.