Key takeaways
- Plain-English definitions of the terms that appear in expert engagement letters and disclosures.
- Covers retainer, Rule 26 report, Daubert, voir dire, IME, and standard of care.
Core terms
- Affidavit / Certificate of Merit, a sworn statement from a qualified physician, required in many states before filing a malpractice claim, attesting the case has medical merit.
- Causation (general vs. specific), general causation asks whether an exposure or act can cause the injury; specific causation asks whether it did so in this patient.
- Consulting expert, an expert engaged to advise counsel without testifying; generally not disclosed and their work is protected from discovery.
- Daubert motion, a motion asking the court to exclude expert testimony as unreliable under Rule 702.
- Differential diagnosis / etiology, the methodology of systematically ruling in and ruling out potential causes; a mainstay of admissible causation opinions.
- Disclosure, the formal identification of testifying experts and their opinions required by procedural rules (e.g., FRCP 26(a)(2)).
- IME, independent medical examination of a party, typically arranged by the defense or an insurer.
- Learned intermediary, the doctrine that a drug or device maker's duty to warn runs to the prescribing physician rather than the patient.
- Life-care plan, a damages document projecting the future medical and support costs of an injured person.
- Retainer, an advance payment against an expert's hourly fees.
- Standard of care, what a reasonably careful practitioner in the same specialty would have done under similar circumstances.
- Voir dire (of an expert), questioning to test an expert's qualifications before opinions are admitted.
About the author

Sales and Marketing Leader, Retain
Michael has spent more than 25 years leading sales and marketing teams in pharmaceuticals, medical devices, and healthcare diagnostics, including 10 product launches and P&L responsibility up to $150M. He writes about how attorneys and physicians actually work together on expert engagements.
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