Average Length of Stay (ALOS)
Average days patients remain admitted in hospital per episode of care
What is Average Length of Stay (ALOS)?
Average length of stay is the average number of days a patient spends in hospital per admission. It shows how efficiently beds are used and how quickly patients move through care.
Shorter stays free beds for other patients, but stays that are too short can lead to readmissions.
How this KPI is measured
- Function
- Operations & Supply Chain
- Sub-function
- Patient Flow
- Industry
- Healthcare
- Type
- Lagging
- Impact
- Operational
- Unit
- days
- Measurement frequency
- Monthly
- Formula
- Total inpatient bed days / Number of discharges in period
How to calculate it
Divide total inpatient bed days by the number of discharges in the period.
For example, if patients used 12,000 bed days and there were 2,000 discharges, ALOS is 6 days.
Compare by specialty and condition, and adjust for case mix, since some conditions naturally need longer stays.
Where it is used
Managing bed capacity
Free beds for demand.
Improving flow
Find delays in discharge.
Comparing services
Benchmark similar cases.
How to improve it
Tips and common mistakes
- Shorter is not always better. Watch readmissions and outcomes.
- Adjust for case mix.
- Separate day cases.
More Operations & Supply Chain kpi library
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