I do not have a form to share with you, although I use one. It is extremely simple with a check box for full duty and one for modified duty with a box for listing accommodations/restrictions and a place for the physician/nurse practitioner to sign and one for the employee, of particular value when they are returning with modifications. There is, then a place for the employee to sign acknowledging review of any accommodations.
In general, the concept of a return to work note from the occupational health/employee health service is to state to management that the employee is either fit to safely and effectively perform the essential job functions of their position, not necessarily the specific job assignment unless it has additional job function capacity requirements, or that they have a disability for which accommodations are being recommended.
For example, your institution might have a class of employees as housekeepers with certain lifting, pushing, pulling, bending, etc, activities which the employee must be deemed capable of safely performing. Some of your housekeeping staff might be assigned to certain areas such as laboratory areas where they may need to wear personal protective equipment, possibly including respirators, to safely enter the area. These housekeepers would then need to be assessed for the additional job function of wearing a respirator prior to clearance. You may want to have such items on your form for the necessary times.
Additionally, you would want an area on the form for listing accommodations/modifications to either the physical activities of the employee or to the work environment. For example, a person who has a cervical strain but needs to manage phone calls and enter data on a computer at the same time, might benefit from being provided with a telephone headset if they do not already have one for their worksite.
Key to all of this is a strong understanding of the essential job tasks of different classes of employees, including issues around safety of the employee to others, which, in a health care setting, includes risks of disease transmission to patients or other employees. Thus, if a practitioner other than the occupational physician/nurse practitioner is being relied on for a preliminary decision, that practitioner should be supplied with a job function description that they should be required to sign and return to employee health. Ideally, your office would then review both the clinical care issues, as much as you are allowed to in non-work-related conditions, and any documentation of capability to perform expected functions prior to final release to work at whatever level is appropriate. Additionally, if there is a question, use of a job/injury-focused functional capacity evaluation can become a part of the clearance and the clearance form information.
You and other list members probably know all this, but it is sometimes helpful to put out all the issues to help construct your own most relevant process and associated forms.
Best.