Clinics are a department of a hospital where outpatients receive treatment, advice or consultations. It can be a private hospital or a nursing-home, or else a specialized hospital. Clinics may admit patients for overnight stays. Clinics are often associated with general health care; their functions differ from country to country, with expertise, from a general out-patient clinic offering a community general diagnoses or treatments without an overnight stay, to a polyclinic where a wide range of health care services (including diagnostics) are offered and a specialist clinic providing advanced diagnostic or treatment services for specific diseases. Doctors at these Clinics refer their patients to a specialist if the need arises. Also, treatment at clinics is less expensive, though they are not open 24/7.