Field Notes
Sampling size without false comfort
Clients sometimes ask for “ten percent of all claims” because that figure sounds objective. In healthcare billing audit reviews, a flat percentage can undersample the risky specialty and oversample stable routine visits.
Start from concentration
If eighty percent of write-offs sit in orthopaedic day surgery, the sample should lean there even if that specialty is a minority of total visits. Document the rationale in the engagement letter so later readers understand the bias was intentional.
Stop conditions
Agree in advance when to stop expanding the sample: for example, after two consecutive batches with no new finding types. Endless expansion burns fees without teaching the billing team anything new.
Communicate uncertainty honestly
Findings packs should say what the sample can and cannot support. Extrapolating a dollar figure to the full year from eighty claims is a management choice, not an audit proof. We would rather leave that multiplication to your finance committee.