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3 Average Length of Stay
Description | Specific Indicators | Corresponding Mandatory Objectives | Corresponding National Indicators | Data Sources |  Alternative Data Sources | ICD Codes | Analysis Check List | Method of Calculation |  Basic Categories | Indicator Comments | Cross-References to Other Sections | References  

  • Annual (by fiscal or calendar year) number of in-patient hospitalization days divided by the total number of in-patient hospital separations for each ICD Chapter, reported in days.


Specific Indicators
  • Average length of stay

Corresponding Mandatory Objectives

  • None

Corresponding National Indicators

  • None

Data Sources (see Resources: Data Sources)
Numerator & Denominator: Hospitalization
Original source: Canadian Institute for Health Information (CIHI)
Distributed by: Provincial Health Planning Database (PHPDB), Health Planning Branch, Ontario MOHLTC
Suggested citation (see Data Citation Notes):
Hospital In-Patient Data [years], Provincial Health Planning Database (PHPDB) Extracted: [date], Health Planning Branch, Ontario MOHLTC

ICD Codes  

Chapter  Chapter Title  ICD Codes


Infectious and Parasitic Diseases  001-139
II   Neoplasms 140-239
III  Endocrine, Nutritional, and Metabolic Diseases and Immunity Disorders 240-279
IV  Diseases of Blood and Blood Forming Organs 280-289
V   Mental Disorders 290-319
VI   Diseases of the Nervous System and Sense Organs 320-389
VII   Diseases of the Circulatory System Cardiovascular Disease 390-459
VIII  Diseases of the Respiratory System  460-519
IX   Diseases of the Digestive System 520-579
X   Disease of the Genitourinary System 580-629
XI   Complications of Pregnancy, Childbirth, and the Puerperium 630-676
XII   Diseases of the Skin and Subcutaneous Tissue 680-709
XIII  Diseases of the Musculoskeletal System and Connective Tissue  710-739
XIV  Congenital Anomalies  740-759
XV  Certain Conditions Originating in the Perinatal Period  760-779
XVI   Symptoms, Signs, and Ill-Defined Conditions 780-799
XVII   Injury and Poisoning 800-999
Supp  External Causes of Injury and Poisoning  E800-E999


Certain infectious and parasitic diseases  A00–B99
II   Neoplasms C00–D49
III   Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism D50–D59
IV   Endocrine, nutritional and metabolic diseases E00–E99
V   Mental and behavioural disorders F00–F99
VI   Diseases of the nervous system G00–G99
VII  Diseases of the eye and adnexa  H00–H59
VIII  Diseases of the ear and mastoid process  H60–H99
IX  Diseases of the circulatory system  I00–I99
Diseases of the respiratory system  J00–J99
XI   Diseases of the digestive system K00–K99
XII   Diseases of the skin and subcutaneous tissue L00–L99
XIII   Diseases of the musculoskeletal system and connective tissue M00–M99
XIV  Diseases of the genitourinary system  N00–N99
XV  Pregnancy, childbirth and the puerperium  O00–O99
XVI   Certain conditions originating in the perinatal period P00–P99
XVII  Congenital malformations, deformations, and chromosomal abnormalities  Q00–Q99
XVIII   Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified R00–R99
XIX   Injury, poisoning and certain other consequences of external causes S00–T99
XX  External causes of morbidity and mortality  V00–Y99

Analysis Check List

  • Suppress numbers <5 or rates and proportions based on counts less than 5.
  • For PHPDB:
    • For numerator: use Inpatient Discharges table from Hospital section of model, use Sum function on “Acute Care Length of Stay”, “ALC Length of Stay” or “Total Length of Stay” attribute.
    • For denominator: use Inpatient Discharges table from Hospital section of model, use Count Distinct function on “CIHI Key” attribute.
  • Select on geography of patient (geography could be postal code, postal code FSA, province, county-municipality, county, region, district health council or public health unit) using geography code not geography name. If geography code is not known, “Prompts” can be used or codes can be looked up in “Geo Names” Code Table. Institution geography can also be selected by linking to “Institution #” table.
  • In hospital data, ICD-9 codes 800-999 refer to the Injury and Poisoning codes whereas these codes in the mortality data set refer to External Causes of Injury and Poisoning codes (e-codes). E-codes can be accessed by linking to the “External Causes” table but problems with double counting can be encountered.

Method of Calculation

annual # of hospitalization days for specific ICD chapter


total number of hospital separations

Basic Categories

  • Age groups: 0-9, 10-19, 20-44, 45-64, 65-74, 75+
  • Sex: male, female
  • Geographic areas of patient residence: health planning region, public health unit, district health council, county, municipality, forward sortation area (FSA) or postal code.
  • ICD Chapter
  • Acute Days, Alternative Level of Care (ALC) Days, Total Days

Indicator Comments

  • Causes are based on the most responsible diagnosis (diagnosis associated with the longest duration of treatment) during a given hospital stay.
  • Length of stay is strongly correlated with number of available hospital beds and is also affected by other factors not related to health status (availability of home care services, characteristics of physician/hospital, time of year etc).
  • Hospitalizations in psychiatric hospitals are excluded.

Alternative Level of Care (ALC) – An ALC patient is one who does not require acute care treatment, but is occupying an acute care bed while awaiting placement. The patient is classified as ALC when the physician gives an order to change the patient's status to "Medically Discharged".

Cross-References to Other Sections

  • None


  • None


Date of Last Revision:January 07, 2003.

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