1. Discharge Abstract Database (DAD) Product Review
Alexandra Cooper
Queen’s University
DLI Ontario Training, November 2016

2. Background
Originally developed in 1963, the Discharge Abstract Database (DAD) captures administrative, clinical and demographic information on hospital discharges (including deaths, sign-outs and transfers). Some provinces and territories also use the DAD to capture day surgery.

3. Background Data availability: Most recent full year – 2015-2016
Historical series – to
Access to full database from CIHI
Data request form
Graduate Student Data Access Program
Data request - $$$
CIHI does have publically accessible data (Quick Stats) and analytical publications – not DAD data but health care statistics
DAD data is also used to populate other CIHI databases, including:
The Hospital Morbidity Database (HMDB)
The Hospital Mental Health Database (HMHDB)

4. Data Source Data is received directly from acute care facilities or
their respective health/regional authority or
ministry/department of health
Facilities in all provinces and territories except Quebec are required to report.
Data from Quebec is submitted to CIHI directly by the ministère de la Santé et des Services sociaux du Québec.

5. Data elements Abstract Identification Length of Stay
Patient Demographics
Admission Data
Discharge Data
Patient Service Information
Service Transfers
Provider Information
Diagnosis Information
Intervention Information
Special Care Information
Blood Information
Reproductive Care Information
Not all in DLI sample files

6. DLI DAD Sample Files 10% sampling of persons from the database
Acute inpatient cases form all provinces/territories except Quebec and British Columbia
Reference dates are randomly assigned to selected individuals
2 files received from CIHI - Clinical and Geographic
Enhanced Clinical and Geographic Files – created by Vince Grey, Western University
Key uses of the DAD
Researchers can become familiar with the structure and content of DAD data
Researchers can explore inter-relationships among DAD data elements (e.g. diagnoses and interventions, Case Mix information)
Researchers can perform preliminary analyses and data mining
Test hypotheses
Reference question answered with DAD - economic burden of diabetic foot complication (foot ulcers and amputations) in Canada

7. DLI DAD Sample Files Fiscal years 2009-2010 to 2010-2011
Geography
Province and Territory (grouped)
Health Region
DLI received first sample files in 2013
Excluded
Stillbirths (ENT_CODE = S)
Cadaveric donations (ADM_CAT = R)
All therapeutic abortion (TA) records

8. DLI DAD Sample Files Access
CIHI DAD Sample files are included in the DLI License as an appendix
Download from the DLI EFT
MAD_CIHI_ICIS_DAM folder (including the Vince’s Enhanced files)
Download from <odesi>
Before accessing files user must accept the license agreement

9. DLI DAD Sample Files Clinical Data File Clinical details:
Diagnoses (1-25): code (ICD-10-CA) and type
Interventions (1-20): code (CCI), status, location, anaesthetic technique
Special care unit visits (1-6): type/number and hours
Length of stay: seven categories (0, 1, 2, 3, 4-5, 6-9, 10+ days)
Newborn weights: six categories (under 750, , , , , grams)
Gestation weeks at delivery: four categories (under 32, 32-33, 34-36, 37+ weeks)

10. DLI DAD Sample Files Geographic Data File Health Region
Case Mix variables:
Major Clinical Category (MCC)
Case Mix Group (CMG)
CMG age category
Resource Intensity Weight (RIW)
Expected Length Of Stay (ELOS)
RIW Atypical code
Resource Intensity Level
Length of Stay: three categories (0, 1-2, 3+ days)
Case-mix methodologies categorize patients into statistically and clinically homogeneous groups based on the collection of clinical and administrative data.
for grouping acute care episodes captured in CIHI’s databases.

11. DLI DAD Sample Files Common Data Elements
Person identifier – meaningless except to identify discharge records for same person within file
Facility province or territories (grouped)
Discharge day – relative to reference day
Admission day – relative to reference day; calculated using collapsed total length of stay
Gender (male or female only)
Age group

12. DLI DAD Sample Files Enhanced Data File
File created by Vince Grey, Western University, to address issue with ICD-10* and CCI* variables in CIHI files
Documentation and Readme about Enhanced files available in <odesi>
*ICD-10 - International Statistical Classification of Diseases and Related Health Problems, 10th revision
*CCI – Canadian Classification of Health Interventions

13. DLI DAD Sample Files Enhanced Data File
Problems in DAD files as distributed by CIHI
Primarily string variables – poses analytical problems and problems for STATA users
No value labels
ICD10 and CCI variables have non-alphabetic characters stripped
e.g. ICD-10 code of A05.80 is in distributed file as A0580; CCI code of 1.AB.86.ML-XX-A is recorded as 1AB86MLXXA
Difficulties in matching codes to the documentation
Files contain up to 25 ICD-10 classifications and up to 20 CCI classifications per record; users may have trouble identifying records in which they are interested
Analytical problems - age when coded as a string may not be treated as an ordinal variable.

14. DLI DAD Sample Files Enhanced Data File
Enhancements to address problems – Clinical file
Creation of 435 flag variables – users can select records that have a broad category of ICD-10 and CCI codes, based on first three characters
Created 2 variables that record the number of ICD-10 and CCI codes on each record (ICDCOUNT; CCICOUNT)
Common disease names added to ICD-10 coding (e.g. chicken pox, measles)
Values of the IDC-10 and CCI variables modified (punctuation added back)
e.g ICD-10 code A0580 now is A05.80
Frequencies for ICD-10 and CCI variables provided

15. DLI DAD Sample Files Enhanced Data File
Enhancements to address problems – Clinical and Geographic files
String variables converted to code
Value labels added

16. Questions