> 1)  How do your organizations handle cash payments to subjects from an accounting perspective?

Miserably.  If the patient owes a dime to the state (taxes, child
support, etc.) state wages (including patient payments) are supposed to
be garnished.  This means a month long process for any payments to be
made, loss of confidentiality, and high patient drop-out rates on
clinical studies. Investigators avoid this method at almost ALL costs.
This process also requires them to have an address (where they will be
30 days from now).

> 2)  Do you have a mechanism to allow for cash payments without completing all of the necessary procurement paperwork or salary papers, etc?

Yes, set up a petty cash account following procedures established by
University Accounting.  This means handling cash and documentation of
all transactions (but can be done in a manner to reduce disclosure of
study participants).

> 3)  Do you have a policy on cash incentive payments to employees for participation (e.g. you do not allow it or you do and treat it as supplemental pay, etc.)?

employees who participate as research subjects are treated as research
subjects.  to be treated as even quasi employees would bring a new set
of conflicts and risks, right?

> 4)  If your cash payments are required to be made by check and normal fiscal processing, how do you maintain confidentiality of the subjects?

Ha!  :)