Wiki CT Scan audit

[MnTwins29]

Been given a new assignment and having never done one of these types of audits, I am looking here for anything I might be missing. I have developed an audit tool where I am reviewing the order for the test (provider, documentation, signature), the report for identifying site and that it is signed, CPT code accuracy, ICD-9 code accuracy, medical necessity against the LCD (Medicare or Medicaid pts only). Is there anything else I should add to this?

Thanks!