Services that Physician Assistants perform can include:

• Evaluation - Eliciting a detailed medical history, performing an appropriate physical examination, delineating problems, and recording information in the medical record.
• Monitoring - Assisting the physician in developing and implementing patient management plans, recording progress notes in office-based and inpatient health care settings.
• Diagnostics - Performing and interpreting (at least to the point of recognizing deviations from the norm) common laboratory, radiologic, cardiographic, and other routine diagnostic procedures used to identify pathophysiologic processes.
• Therapeutics - Performing routine procedures such as infections, immunizations, suturing and wound care, managing simple conditions produced by infection or trauma, participating in the management of more complex illness and injury, and taking initiative in performing evaluation and therapeutic procedures in response to life-threatening situations.
• Counseling - Instructing and counseling patients regarding compliance with prescribed therapeutic regimens, normal growth and development, family planning, situational adjustment reactions and health maintenance.
• Referral - Facilitating the referral patients to the community's health and social service agencies when appropriate.

(http://www.medinfo.ufl.edu/pa/program/pa.htm)

"The extent of the involvement by physician assistants in the assessment and treatment of patients depends largely on the complexity and acuity of the patient's condition as well as their training, experience, and preparation as adjudged by the supervising physician." (http://www.medinfo.ufl.cdu/pa/program/pa.htm)