An Associate of Science in Nursing (ASN) is a tertiary education nursing degree which typically take 2–3 years to complete. In the United States, this type of degree is usually awarded by community colleges or similar nursing schools. Some four year colleges also offer this degree. Students awarded an Associate of Science in Nursing are qualified to sit for the NCLEX-RN and apply for licensure as a Registered Nurse. Students enrolled in an Associate of Science in Nursing program would take courses in nursing, anatomy, physiology, microbiology, chemistry, nutrition, psychology and other social and behavioral sciences. The curriculum will also require supervised clinical experience. Some hospital-based nursing schools that granted diplomas altered their curriculum to offer associate degrees.