Knowledge of basic visual testing and diagnostic procedures, including pupillary measurement, visual acuity, extraocular muscle assessment, confrontation visual field testing, auto lensometry, auto refraction, Tonopen and/or iCare intraocular pressure measurement, as well as basic Slit lamp skills such as Goldmann tonometry and anterior chamber angle assessment. The fraudulent LinkedIn messages and emails, which do not originate from any Executives LinkedIn account or of UnitedHealth Group's email domains, or those of any of its operating divisions, supposedly conducts an interview via a Zoom meeting, offers a work from home job at Optum, emails an application, sends a fake check by next day delivery through USPS and asks recipients to pay a vendor a large dollar amount.