Final answer:
The main obstacle of the scientist-practitioner model in psychology is the difficulty integrating research and practice.
Step-by-step explanation:
The main obstacle of the scientist-practitioner model in psychology is the difficulty integrating research and practice. The scientist-practitioner model is based on the idea that psychological practitioners should also be actively involved in conducting and applying research. However, it can be challenging to balance the demands of both research and practice. For example, practitioners may find it difficult to keep up with the latest research findings while also providing quality patient care.