Employments may differ in terms of how much the employee is supposed to work – part time or full time, right? But how do you refer to this phenomenon? Do you talk about "the extent of the employment" or "the work rate of the employment" or... what?
I want to say
The work rate of an adjunct position should be dictated by the requirements of the relevant institution.
but I'm not sure whether "work rate" is the correct word to use here, or whether it should be "extent" or something else entirely.