Number of calendar days a patient remains in a health care facility or is an inpatient in the hospital during an episode of illness or due to an injury. LOS statistics report the average number of days spent in a health care facility per admission and discharge. Also referred to as average length of stay, days of stay, discharge days, duration of inpatient hospitalization , and inpatient days of stay .

Type of group insurance in which an employee is insured for an amount dependent on the length of time he or she has been employed for the employer.

Type of cases that fall outside, either longer or shorter than typical, from the average for a specific diagnosis, procedure, or diagnostic-related group.

Curved transparent pieces of plastic or glass that are shaped, molded, or ground to refract light in a specific way, as in eyeglasses, microscopes, or cameras. Corrective lenses may be prescribed by an ophthalmologist or optometrist to improve vision.

On organizational letterhead, a formal document detailing needs and purposes by a requestor for a federally funded project. In addition, a letter of support is required from the federal project officer on his or her organizational letterhead.

On organizational letterhead, a document from the federal project officer justifying the need for Centers for Medicare and Medicaid Services (CMS) data and supporting the requestor’s use of such data.

System of applying the same insurance commission payment rate to the premium for each year that a policy is in force.

Medical services provided to patients for conditions arising, often unexpectedly, that need at least one physician experienced in emergency care on duty in the emergency care area. There must be in-hospital physician coverage by members of the medical staff or by senior-level residents for at least medical, surgical, orthopedic, obstetric, gynecologic, pediatric, and anesthesiology services. When coverage can be demonstrated to meet suitably through another mechanism, an equivalent will be considered to exist for purposes of compliance with the requirement. Other specialty consultation must be available within approximately 30 minutes. Initial consultation through two-way voice communication is acceptable. The hospital’s scope of services must include in-house capabilities for managing physical and related emotional problems on a definitive basis. Also see emergency services .