referring_doctor object format:

Key	Type	POST/PUT requests	Notes
first_name	string	Optional
middle_name	string	Optional
last_name	string	Optional
suffix	string	Optional
npi	string	Optional
provider_qualifier	string	Optional	Can be one of following, '', '0B'(State License #), '1G'(Provider UPIN #), 'G2'(Provider Commercial #)
provider_number	string	Optional
address	string	Optional
email	string	Optional
phone	string	Optional	Should follow format "xxx-xxx-xxxx"
fax	string	Optional	Should follow format "xxx-xxx-xxxx"
specialty	string	Optional	Can be one of following, '', 'Acupuncture', 'Advanced Practice Midwife', 'Aesthetic Medicine', 'Aesthetician', 'Allergist/Immunologist', 'Anesthesiologist', 'Cardiac Electrophysiologist', 'Cardiologist', 'Cardiothoracic Surgeon', 'Child/Adolescent Psychiatry', 'Chiropractor', 'Clinical Social Worker', 'Colorectal Surgeon', 'Correactology', 'Cosmetic Medicine', 'Counselor Mental Health', 'Counselor Professional', 'Counselor', 'Dentist', 'Diabetology', 'Dermatologist', 'Diagnostic Medical Sonographer', 'Dietitian, Registered', 'Ear-Nose-Throat Specialist (ENT)', 'Emergency Medicine Physician', 'Endocrinologist', 'Endodontist', 'Epidemiologist', 'Family Practitioner', 'Gastroenterologist', 'General Practice', 'General Surgeon', 'Geneticist', 'Geriatrician', 'Gerontologist', 'Gynecologist (no OB)', 'Gynegologic Oncologist', 'Hand Surgeon', 'Hematologist', 'Home Care', 'Hospice', 'Hospitalist', 'Infectious Disease Specialist', 'Integrative and Functional Medicine', 'Integrative Medicine', 'Internist', 'Interventional Radiology', 'Laboratory Medicine Specialist', 'Laser Surgery', 'Massage Therapist', 'Naturopathic Physician', 'Neonatologist', 'Nephrologist', 'Neurologist', 'Neuropsychology', 'Neurosurgeon', 'Not Actively Practicing', 'Nuclear Medicine Specialist', 'Nurse Practitioner', 'Nursing', 'Nutritionist', 'Obstetrician/Gynecologist', 'Occupational Medicine', 'Occupational Therapist', 'Oncologist', 'Ophthalmologist', 'Optometrist', 'Oral Surgeon', 'Orofacial Pain', 'Orthodontist', 'Orthopedic Surgeon', 'Orthotist', 'Other', 'Pain Management Specialist', 'Pathologist', 'Pediatric Dentist', 'Pediatric Gastroenterology', 'Pediatric Surgeon', 'Pediatrician', 'Perinatologist', 'Periodontist', 'Physical Medicine and Rehab Specialist', 'Physical Therapist', 'Physician Assistant', 'Plastic Surgeon', 'Podiatrist', 'Preventive-Aging Medicine', 'Preventive Medicine/Occupational-Environmental Medicine', 'Primary Care Physician', 'Prosthetist', 'Prosthodontist', 'Psychiatrist', 'Psychologist', 'Public Health Professional', 'Pulmonologist', 'Radiation Oncologist', 'Radiologist', 'Registered Nurse', 'Religious Nonmedical Practitioner', 'Reproductive Endocrinologist', 'Reproductive Medicine', 'Rheumatologist', 'Sleep Medicine', 'Speech-Language Pathologist', 'Sports Medicine Specialist', 'Urologist', 'Urgent Care', 'Vascular Surgeon'