Sub-centres have been established for every 5,000 population (3,000 in hilly, tribal and backward areas) and are manned by a female health worker, also called the Auxiliary Nurse Mid-wife (ANM) and a male health worker.
Primary Health Centres which are referral units for about six sub-centres have been established for every 30,000 population (20,000 in hilly, tribal and backward areas).
PHCs provide outpatient services, and the majority also have four to six in-patient beds and staff comprises of one medical officer and 14 para-medical workers
Community Health Centres are the first referral units for four PHCs and also provides specialist care. According to the norms each CHC (for every 1 lakh population) should have at least 30 beds, one operation theatre, X-ray machine, labour room and laboratory facilities and should be staffed by at least four specialists i.e. a surgeon, a physician, a gynaecologist and a paediatrician supported by 21 para-medical and other staff.
Primary health care - services offered by the doctors, nurses and other small clinics which are contacted first by the patient for any sickness
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