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Average Length of Stay (ALOS)

What is average length of stay (ALOS)?

Average length of stay (ALOS) is the number of days (on average) that a patient spends in the hospital.

To calculate ALOS, divide the total number of days in the hospital for all patients during a certain amount of time by the number of admissions or discharges. Day cases are not included in these calculations.

What is the importance of ALOS?

ALOS is often used to indicate efficiency in a hospital. In general, a shorter stay reduces the cost per discharge and frees up more beds for new patients.

A shorter length of stay (LOS) is also more beneficial for the patient. This is because the longer a patient is in the hospital, the greater their risk of developing a healthcare-acquired infection (HAI).

In general, a high LOS correlates to higher mortality rates, which is why it is crucial for hospitals to implement practices that lower ALOS.