At trial, the expert's direct testimony is divided into five main parts:
- Qualifications as an expert to render opinion testimony.
- The expert's assignment and how it was performed.
- Findings of fact based on research and testing.
- The expert's opinions.
- Reasons that support the conclusions.
Expert opinions may be based on facts found, testing or research conducted, or a series of hypothetical questions developed with the expert by the sponsoring attorney and based on facts, evidence and proof developed at trial.