MemoA01
ClientDr. ABC
Client OrganizationABC Department
Version2.0
StatusDraft
ClassificationInternal use only
Note: Data preparation is completed in Memo A00. This memo summarizes the analytic NACRS file.

1 Overview

1.1 Introduction

The purpose of this memo is to summarize selected variables from the analytic NACRS file. It provides a concise description of the data source and presents coverage, standardized descriptive statistics, and data-quality results.

Data preparation is completed in Memo A00. That memo reads the source workbook, constructs the research variables, and writes analytic_nacrs.rds. This memo does not rebuild those fields and does not repeat their definitions. CTAS remains a source field. Emergency stay (los_min), hospitalization (admitted_flag), and the related indicators are already present in the analytic file.

The memo is organized as follows:

  • Data identifies the analytic file written by Memo A00, reports the number of records and variables, and lists all available variables, without displaying row-level records.
  • Analysis reports date and fiscal-year coverage, summarizes registered measures with methods suited to each variable type, and presents quality-status distributions and consistency checks.

1.2 Data

Training data notice: The NACRS data used in this memo are randomly generated synthetic data intended solely for training and demonstration purposes. They do not represent real patients or actual operational records. Preprocessing, including construction of the derived research variables, is completed in Memo A00. This memo reads that analytic file only.

Data directory: data

Loaded NACRS analytic data set
Dataset Alias File Rows Columns Class
imported_data_001 nacrs analytic_nacrs.rds 30000 50 tbl_df, tbl, data.frame
Variables (50)
  1. patient_id
  2. visit_id
  3. facility_id
  4. health_zone
  5. sex
  6. age
  7. postal_fsa
  8. arrival_datetime
  9. arrival_mode
  10. ctas_level
  11. chief_complaint
  12. main_diagnosis_icd10
  13. secondary_diagnosis_1
  14. secondary_diagnosis_2
  15. intervention_1
  16. intervention_2
  17. consult_service
  18. injury_flag
  19. mental_health_flag
  20. pain_score
  21. triage_wait_min
  22. physician_wait_min
  23. disposition
  24. revisit_72h_flag
  25. discharge_datetime
  26. disposition_decision_datetime
  27. hospital_id
  28. hospital_region
  29. patient_residence
  30. smoking
  31. obesity
  32. cardiometabolic_history
  33. asthma_history
  34. prior_ed_visits
  35. ed_arrival_severity
  36. dataset_version
  37. hospital_name
  38. hospital_city
  39. ed_service_listed
  40. age10
  41. season
  42. asthma_visit
  43. pre_disposition_los_min
  44. post_disposition_los_min
  45. los_min
  46. admitted_flag
  47. lwbs_flag
  48. ambulance_flag
  49. fiscal_year
  50. timing_quality_flag

2 Analysis

2.1 NACRS standardized profile

The variable registry maps 50 of 50 registered NACRS variables. The loaded data contain 30000 records.

2.2 Coverage

Datetime ranges are displayed in UTC.

NACRS datetime coverage
Variable Non-missing Missing Earliest Latest
Arrival datetime 30000 0 2025-01-01 00:17 2025-12-28 23:42
Discharge datetime 30000 0 2025-01-01 02:42 2025-12-29 02:58
Disposition decision datetime 30000 0 2025-01-01 02:20 2025-12-29 02:23
NACRS reporting-period coverage
Variable Coverage
Fiscal year 2024-25, 2025-26

2.3 Main measures

The registry selects 8 continuous measures and 31 categorical measures for the main profile.

2.3.1 Continuous measures

Selected NACRS continuous measures
Variable Mean (SD) Median Min-Max P1 P5 P10 Q1 Q2 Q3 P90 P95 P99 Missing N Non-missing Missing %
Age (years) 44.16 (21.55) 46.00 0.00 - 89.00 1.00 5.00 10.00 30.00 46.00 61.00 71.00 76.00 83.00 0 30000 30000 0.000000
Pain score (points) 4.98 (3.17) 5.00 0.00 - 10.00 0.00 0.00 1.00 2.00 5.00 8.00 9.00 10.00 10.00 0 30000 30000 0.000000
Triage wait (min) 14.00 (3.87) 14.00 1.00 - 31.00 5.00 8.00 9.00 11.00 14.00 17.00 19.00 20.00 23.00 0 30000 30000 0.000000
Physician wait (min) 37.77 (11.43) 36.00 10.00 - 109.00 18.00 22.00 25.00 29.00 36.00 44.00 53.00 59.00 70.00 605 30000 29395 2.016667
Length of stay (min) 213.87 (88.57) 196.00 49.00 - 1054.00 83.00 105.00 120.00 152.00 196.00 257.00 329.00 380.00 503.00 0 30000 30000 0.000000
Prior 12-month ED visits (visits) 0.60 (0.77) 0.00 0.00 - 5.00 0.00 0.00 0.00 0.00 0.00 1.00 2.00 2.00 3.00 0 30000 30000 0.000000
Pre-care ED severity (arbitrary score) 0.24 (1.15) 0.23 -4.32 - 4.88 -2.39 -1.63 -1.24 -0.54 0.23 1.02 1.72 2.14 2.93 0 30000 30000 0.000000
Age centered at 50 per 10 years (decades) -0.58 (2.16) -0.40 -5.00 - 3.90 -4.90 -4.50 -4.00 -2.00 -0.40 1.10 2.10 2.60 3.30 0 30000 30000 0.000000

2.3.2 Timing measures

Timing summaries use 29395 quality-eligible records and exclude 605 records. Excluded records remain visible in the Data quality section.

Quality-eligible NACRS timing measures
Variable Mean (SD) Median Min-Max P1 P5 P10 Q1 Q2 Q3 P90 P95 P99 Missing N Non-missing Missing %
Pre-disposition length of stay (min) 187.35 (85.92) 170.00 40.00 - 1014.00 63.00 83.00 97.00 127.00 170.00 228.00 298.00 350.00 471.00 0 29395 29395 0
Post-disposition length of stay (min) 26.60 (15.28) 22.00 4.00 - 173.00 8.00 11.00 13.00 16.00 22.00 32.00 46.00 57.00 83.00 0 29395 29395 0

2.3.3 Categorical measures

Each variable is displayed separately. Coded variables show up to the 20 most frequent codes, followed by Other and Missing where applicable.

2.3.3.1 Hospital health zone (legacy labels)

health_zone
Category Count n (%)
Edmonton 10530 (35.1%)
Calgary 10328 (34.4%)
Central 3734 (12.4%)
South 2755 (9.2%)
North 2653 (8.8%)

2.3.3.2 Sex

sex
Category Count n (%)
F 15087 (50.3%)
M 14913 (49.7%)

2.3.3.3 Postal FSA

postal_fsa
Category Count n (%)
T5J 10583 (35.3%)
T2P 10444 (34.8%)
T8V 8973 (29.9%)

2.3.3.4 Arrival mode

arrival_mode
Category Count n (%)
Walk-in 25790 (86.0%)
Ground ambulance 4210 (14.0%)

2.3.3.5 CTAS level

ctas_level
Category Count n (%)
1 3872 (12.9%)
2 6906 (23.0%)
3 8618 (28.7%)
4 6876 (22.9%)
5 3728 (12.4%)

2.3.3.6 Chief complaint

chief_complaint
Category Count n (%)
Shortness of breath 6399 (21.3%)
Wheezing 2726 (9.1%)
Nausea/vomiting 1445 (4.8%)
Minor trauma 1440 (4.8%)
Mental health concern 1413 (4.7%)
Cough 1410 (4.7%)
Laceration 1402 (4.7%)
Abdominal pain 1400 (4.7%)
Urinary symptoms 1397 (4.7%)
Syncope 1394 (4.6%)
Allergic reaction 1393 (4.6%)
Headache 1383 (4.6%)
Dizziness 1380 (4.6%)
Fever 1379 (4.6%)
Chest pain 1373 (4.6%)
Back pain 1351 (4.5%)
Weakness 1315 (4.4%)

2.3.3.7 Main diagnosis ICD-10

main_diagnosis_icd10
Category Count n (%)
J45.9 9159 (30.5%)
R11 1445 (4.8%)
S09.9 1440 (4.8%)
F41.9 1413 (4.7%)
S01.9 1402 (4.7%)
R10.9 1400 (4.7%)
N39.0 1397 (4.7%)
R55 1394 (4.6%)
T78.4 1393 (4.6%)
R51.9 1383 (4.6%)
R42 1380 (4.6%)
R50.9 1379 (4.6%)
R06.0 1376 (4.6%)
R07.4 1373 (4.6%)
M54.5 1351 (4.5%)
R53 1315 (4.4%)

2.3.3.8 Secondary diagnosis 1

secondary_diagnosis_1
Category Count n (%)
J45.9 5990 (20.0%)
MissingNA 24010 (80.0%)

2.3.3.9 Secondary diagnosis 2

secondary_diagnosis_2
Category Count n (%)
E11.9 5979 (19.9%)
MissingNA 24021 (80.1%)

2.3.3.10 Intervention 1

intervention_1
Category Count n (%)
Bronchodilator 8991 (30.0%)
None 7393 (24.6%)
X-ray 6862 (22.9%)
ECG 6754 (22.5%)

2.3.3.11 Intervention 2

intervention_2
Category Count n (%)
None 21009 (70.0%)
Pulse oximetry 8991 (30.0%)

2.3.3.12 Consult service

consult_service
Category Count n (%)
None 20589 (68.6%)
Internal Medicine 9411 (31.4%)

2.3.3.13 Ambulance arrival

ambulance_flag
Category Count n (%)
No 25790 (86.0%)
Yes 4210 (14.0%)

2.3.3.14 Injury indicator

injury_flag
Category Count n (%)
No 27158 (90.5%)
Yes 2842 (9.5%)

2.3.3.15 Mental health indicator

mental_health_flag
Category Count n (%)
No 28587 (95.3%)
Yes 1413 (4.7%)

2.3.3.16 Disposition

disposition
Category Count n (%)
Discharged home 23585 (78.6%)
Admitted inpatient 5810 (19.4%)
Left without being seen 605 (2.0%)

2.3.3.17 Admitted

admitted_flag
Category Count n (%)
No 24190 (80.6%)
Yes 5810 (19.4%)

2.3.3.18 Left without being seen

lwbs_flag
Category Count n (%)
No 29395 (98.0%)
Yes 605 (2.0%)

2.3.3.19 72-hour revisit

revisit_72h_flag
Category Count n (%)
No 28123 (93.7%)
Yes 1877 (6.3%)

2.3.3.20 Hospital region

hospital_region
Category Count n (%)
Edmonton 10530 (35.1%)
Calgary 10328 (34.4%)
Other 9142 (30.5%)

2.3.3.21 Patient residence

patient_residence
Category Count n (%)
Edmonton 10583 (35.3%)
Calgary 10444 (34.8%)
Other 8973 (29.9%)

2.3.3.22 Pre-episode smoking

smoking
Category Count n (%)
No 23324 (77.7%)
Yes 6676 (22.3%)

2.3.3.23 Pre-episode obesity

obesity
Category Count n (%)
No 22204 (74.0%)
Yes 7796 (26.0%)

2.3.3.24 Cardiometabolic history

cardiometabolic_history
Category Count n (%)
No 24021 (80.1%)
Yes 5979 (19.9%)

2.3.3.25 Prior asthma history

asthma_history
Category Count n (%)
No 24010 (80.0%)
Yes 5990 (20.0%)

2.3.3.26 Data release

dataset_version
Category Count n (%)
2.0-2026-10-09 30000 (100.0%)

2.3.3.27 Season of ED arrival

season
Category Count n (%)
Summer 7550 (25.2%)
Spring 7498 (25.0%)
Winter 7497 (25.0%)
Autumn 7455 (24.9%)

2.3.3.28 Asthma as main ED diagnosis

asthma_visit
Category Count n (%)
No 20841 (69.5%)
Yes 9159 (30.5%)

2.3.3.29 Hospital Name

hospital_name
Category Count n (%)
Canmore General Hospital 1133 (3.8%)
Devon General Hospital 1100 (3.7%)
Fort Saskatchewan Community Hospital 1083 (3.6%)
Misericordia Community Hospital 1073 (3.6%)
Leduc Community Hospital 1060 (3.5%)
University of Alberta Hospital 1055 (3.5%)
Foothills Medical Centre 1054 (3.5%)
South Health Campus 1051 (3.5%)
WestView Hospital and Continuing Care Centre 1050 (3.5%)
Sturgeon Community Hospital 1041 (3.5%)
Strathmore District Health Services 1040 (3.5%)
Mineral Springs Hospital 1032 (3.4%)
Grey Nuns Community Hospital 1028 (3.4%)
Royal Alexandra Hospital 1023 (3.4%)
Redwater Health Centre 1017 (3.4%)
Peter Lougheed Centre 1011 (3.4%)
Rockyview General Hospital 1011 (3.4%)
Didsbury District Health Services 1006 (3.4%)
Oilfields General Hospital 1003 (3.3%)
High River General Hospital 987 (3.3%)
Drumheller Health Centre 972 (3.2%)
Lacombe Hospital and Care Centre 959 (3.2%)
Medicine Hat Regional Hospital 928 (3.1%)
Brooks Health Centre 921 (3.1%)
Stettler Hospital and Care Centre 915 (3.0%)
Chinook Regional Hospital 906 (3.0%)
Marshall Eliuk Peace River Community Health Centre 894 (3.0%)
Northern Lights Regional Health Centre 894 (3.0%)
Red Deer Regional Hospital Centre 888 (3.0%)
Grande Prairie Regional Hospital 865 (2.9%)

2.3.3.30 Hospital City

hospital_city
Category Count n (%)
Edmonton 4179 (13.9%)
Calgary 4127 (13.8%)
Canmore 1133 (3.8%)
Devon 1100 (3.7%)
Fort Saskatchewan 1083 (3.6%)
Leduc 1060 (3.5%)
Stony Plain 1050 (3.5%)
St. Albert 1041 (3.5%)
Strathmore 1040 (3.5%)
Banff 1032 (3.4%)
Redwater 1017 (3.4%)
Didsbury 1006 (3.4%)
Diamond Valley 1003 (3.3%)
High River 987 (3.3%)
Drumheller 972 (3.2%)
Lacombe 959 (3.2%)
Medicine Hat 928 (3.1%)
Brooks 921 (3.1%)
Stettler 915 (3.0%)
Lethbridge 906 (3.0%)
Fort McMurray 894 (3.0%)
Peace River 894 (3.0%)
Red Deer 888 (3.0%)
Grande Prairie 865 (2.9%)

2.3.3.31 Ed Service Listed

ed_service_listed
Category Count n (%)
Yes 30000 (100.0%)

2.4 Data quality

NACRS quality-status distribution
Variable Status Count n (%)
Timing quality status Pass 29395 (98.0%)
Timing quality status Missing 605 (2.0%)
NACRS timing consistency checks
Check Evaluated Violations Status
Arrival <= decision <= discharge 30000 0 Pass
Pre-disposition LOS matches timestamps 30000 0 Pass
Post-disposition LOS matches timestamps 30000 0 Pass
Pre + post LOS equals total LOS 30000 0 Pass
Timing durations are non-negative 30000 0 Pass

2.4.1 Variable handling

Identifiers and internal provenance fields are registered for schema validation but are excluded from public summary tables. Missing values remain distinct from valid zero values.

3 Shared release

This memo uses unified synthetic release 2.0-2026-10-09, built from the same NACRS/DAD source files as A07–A09. Hospital location and patient residence are separate variables. See A00 for definitions and provenance.