General:
* Observational
* Experimental
* Factual
* Data-driven
* Evidence-based
* Practical
* Real-world
* Objective
More specific:
* Scientific: Scientifically proven, verifiable
* Experimental: Based on experimentation, controlled study
* Quantitative: Measured, numerical, statistical
* Inductive: Based on observation and generalization
* Pragmatic: Practical, focused on results
The best synonym depends on the specific meaning you want to convey.