Origin of the title "Charge Nurse?"

I have heard that the title "Charge Nurse" started when hospital/nursing home administrations were trying to avoid paying nurses overtime pay. By elevating them from a plain ole nurse to a "Charge Nurse," the nurses were then going to be considered supervisors who would not need to be paid overtime. (In the same way a fast food joint can have numerous so-called "assistant managers" who, most likely, will never actually become managers, but don't get overtime pay...)

Anyway, that little plot never worked--and thankfully nurses still receive overtime pay-- but the title "Charge Nurse" stuck.
Has anyone else ever heard that explanation for the origin of the title "Charge Nurse?" I've always been curious about whether it is true...