--- title: Emergency department patients who left within four hours by hospital and patient group, Australia resource: https://publicdata.au/d/au-ed-time-within-4-hours/ publisher: Australian Institute of Health and Welfare licence: CC BY 4.0 licence_url: https://creativecommons.org/licenses/by/4.0/ version: 2026-10-27 rows: 36289 fields: 9 source: https://myhospitalsapi.aihw.gov.au/api/v1/measure-downloads/myh-ed source_sha256: 49d99ec1517e3ef43abe55678bfc93d595339aee14d1fae24dae44ef460e0a92 language: en-AU operator: National Digital not_endorsed: true --- # Emergency department patients who left within four hours by hospital and patient group, Australia The share of emergency department patients who left within four hours of arriving, for each public hospital, network and state each year since 2011-12, from AIHW MyHospitals. Published by Australian Institute of Health and Welfare under CC BY 4.0. National Digital converted the publisher's file to other formats. It renamed and typed the columns and kept only those the schema lists. It made each suppressed value a null with a flag. It kept the publisher's marker for each empty cell in a markers column. National Digital made these changes, and the publisher is not responsible for them. Australian Institute of Health and Welfare has not endorsed this site. Also called: ED four hour rule by hospital, Emergency department length of stay within 4 hours, Patients leaving ED within four hours. ## Download Latest version, redirects to `https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/`: - csv: https://publicdata.au/d/au-ed-time-within-4-hours/latest/data.csv (4.4 MB) - xlsx: https://publicdata.au/d/au-ed-time-within-4-hours/latest/data.xlsx (1.5 MB) - json: https://publicdata.au/d/au-ed-time-within-4-hours/latest/data.json (11 MB) - parquet: https://publicdata.au/d/au-ed-time-within-4-hours/latest/data.parquet (168 KB) - sqlite: https://publicdata.au/d/au-ed-time-within-4-hours/latest/data.sqlite (7.0 MB) - duckdb: https://publicdata.au/d/au-ed-time-within-4-hours/latest/data.duckdb - ndjson: https://publicdata.au/d/au-ed-time-within-4-hours/latest/data.ndjson (11 MB) - csv.gz: https://publicdata.au/d/au-ed-time-within-4-hours/latest/data.csv.gz (353 KB) Pinned version 2026-10-27: `https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/data.`. Dated versions keep their content. ## Query The query API returns only the rows you ask for, as JSON, NDJSON or CSV, from the same typed rows as the files. It needs no key. Rows: https://publicdata.au/api/v1/datasets/au-ed-time-within-4-hours/rows. Counts and sums: https://publicdata.au/api/v1/datasets/au-ed-time-within-4-hours/aggregate. - Rows: https://publicdata.au/api/v1/datasets/au-ed-time-within-4-hours/rows?year=eq.2024%E2%80%9325&reporting_unit_type=eq.State&patient_cohort=eq.All%20patients&limit=5 - Aggregate: https://publicdata.au/api/v1/datasets/au-ed-time-within-4-hours/aggregate?group=reporting_unit&metric=avg.share_within_4_hours&year=eq.2024%E2%80%9325&reporting_unit_type=eq.State&patient_cohort=eq.All%20patients Each filter is `field=operator.value` in the query string, and every filter must match. A number or date field compares as a number or date, and a text field compares as text. Values are case-sensitive, except that `like` and `ilike` ignore case in the ASCII letters A to Z. Prefix `not.` to negate a filter, as `not.eq.value`. Operators: `eq.value`, `neq.value`, `gt.value`, `gte.value`, `lt.value`, `lte.value`, `like.*text*`, `ilike.*text*`, `in.(a,b,c)`, `is.null`. - `select`: Fields to return, comma-separated. Every field when absent. - `order`: `field.asc` or `field.desc`, comma-separated. When absent, rows come in the order of the file they are read from. For the newest versions that is the version's own data.parquet, which keeps the publisher's order unless the dataset sorted it. Any other version is read from the Parquet file the answer names in `file`, and when that file is sorted the answer names its sort in `order`, which ties follow too. - `limit`: Rows per page, 1 to 10,000. 100 when absent. - `offset`: Rows to skip. The `next` URL in each answer sets it for you. - `group`: On `aggregate`, fields to group by, comma-separated. - `metric`: On `aggregate`, `count`, `sum.field`, `avg.field`, `min.field` or `max.field`, comma-separated. `count` when absent. - `format`: `json`, `ndjson` or `csv`. JSON carries the provenance header, and the others carry it in response headers. Without a version the API answers from the newest version, and that answer changes when the publisher releases again. Put `versions//` before `rows` or `aggregate` for an answer from that version alone. Every version with a table can be queried, and `/api/v1/datasets//versions` lists them. A query on a version the database does not hold is read from its Parquet file, and one that would read too much of it is refused with DuckDB SQL that answers it from the file. The API allows 60 requests in 10 seconds from one address. Above that it answers 429 for 10 seconds with a `Retry-After` header, a `RateLimit-Policy` header and a JSON body that gives the limit. Every API answer carries the same `RateLimit-Policy`. A client should wait the `Retry-After` seconds, or read the files, which have no limit. OpenAPI for this dataset: https://publicdata.au/d/au-ed-time-within-4-hours/openapi.json ## Explore Charts and dashboards in the browser: https://publicdata.au/d/au-ed-time-within-4-hours/explore/. A dashboard can be shared as a link or embedded. ## Smaller files - by `state`: https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/by/state/index.json lists 9 files ## Fields | field | type | publisher's header | note | |---|---|---|---| | `reporting_unit` | string | Reporting unit | | | `reporting_unit_type` | string | Reporting unit type | | | `state` | string | State | | | `peer_group` | string | Peer group | | | `year` | string | Year | | | `patient_cohort` | string | Patient cohort | | | `presentations` | integer | Number of presentations | | | `share_within_4_hours` | number | Percentage who depart ED within 4 hrs | The fraction of patients who departed the emergency department within four hours of arrival, 0.8 for 80 per cent. | | `peer_group_average` | number | Peer group average | | Key: `reporting_unit, reporting_unit_type, year, patient_cohort`. ## Versions - 2026-10-27: 36289 rows, 9 fields, sha256 49d99ec1517e. https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/ Machine-readable: https://publicdata.au/d/au-ed-time-within-4-hours/versions.json, https://publicdata.au/d/au-ed-time-within-4-hours/changes.json, https://publicdata.au/d/au-ed-time-within-4-hours/datapackage.json, https://publicdata.au/d/au-ed-time-within-4-hours/schema.json, https://publicdata.au/d/au-ed-time-within-4-hours/history.tar.zst ## Part of AIHW MyHospitals - [Hospitals, Local Hospital Networks and Primary Health Networks in MyHospitals, Australia](https://publicdata.au/d/au-hospitals-myhospitals/) - [Reported measures and their codes in MyHospitals, Australia](https://publicdata.au/d/au-myhospitals-reported-measures/) - [Reporting unit mappings to health networks and states in MyHospitals, Australia](https://publicdata.au/d/au-myhospitals-reporting-unit-mappings/) - [Reporting unit codes and alternative names in MyHospitals, Australia](https://publicdata.au/d/au-myhospitals-reporting-units/) - [Emergency department patients seen on time by hospital and triage category, Australia](https://publicdata.au/d/au-ed-patients-seen-on-time/) - [Emergency department presentations by hospital and triage category, Australia](https://publicdata.au/d/au-ed-presentations/) - [Time spent in emergency departments by hospital and patient group, Australia](https://publicdata.au/d/au-ed-time-in-ed/) - [Cancer surgery waiting times by hospital and cancer type, Australia](https://publicdata.au/d/au-cancer-surgery-waiting-times/) - [Elective surgery waiting times by hospital and urgency category, Australia](https://publicdata.au/d/au-elective-surgery-waiting-times/) - [Elective surgery waiting times by hospital and intended procedure, Australia](https://publicdata.au/d/au-elective-surgery-waiting-times-by-procedure/) - [Elective surgery waiting times by hospital and surgical specialty, Australia](https://publicdata.au/d/au-elective-surgery-waiting-times-by-specialty/) ## Same subject, other publishers - [Emergency department busyness by day and hour, Queensland](https://publicdata.au/d/qld-emergency-department-busyness/) (Qld) - [Public hospital emergency departments and minor injury clinics, Queensland, live list](https://publicdata.au/d/qld-emergency-department-facilities/) (Qld) - [People waiting and median waits in emergency departments, Queensland, live](https://publicdata.au/d/qld-emergency-department-waits-now/) (Qld) - [Public hospital locations, South Australia](https://publicdata.au/d/sa-public-hospitals/) (SA) - [Measles public exposure sites, Victoria](https://publicdata.au/d/vic-measles-exposure-sites/) (Vic) - [Air quality monitoring by hour, ACT](https://publicdata.au/d/act-air-quality/) (ACT) - [Public dental waiting lists by clinic, Queensland, latest quarter](https://publicdata.au/d/qld-public-dental-waiting-lists/) (Qld) - [Elective surgery by specialty and hospital, Queensland, each quarter](https://publicdata.au/d/qld-elective-surgery-by-specialty/) (Qld) - [Elective surgery by urgency category and hospital, Queensland, each quarter](https://publicdata.au/d/qld-elective-surgery-by-category/) (Qld) - [Private hospital locations, South Australia](https://publicdata.au/d/sa-private-hospitals/) (SA) ## Attribution and citation Based on Australian Institute of Health and Welfare material. Australian Institute of Health and Welfare, Australian Government, MyHospitals Data API, emergency department data extract, sourced 26 October 2026, https://myhospitalsapi.aihw.gov.au/, licensed under CC BY 4.0. The licence requires the publisher's attribution. We ask that you also name publicdata.au and link to the version you used. Plain text: Based on Australian Institute of Health and Welfare material. Australian Institute of Health and Welfare, Australian Government, MyHospitals Data API, emergency department data extract, sourced 26 October 2026, https://myhospitalsapi.aihw.gov.au/, licensed under CC BY 4.0. Serialised and versioned by National Digital at publicdata.au, https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/ Harvard: Australian Institute of Health and Welfare (2026) Emergency department patients who left within four hours by hospital and patient group, Australia, version 2026-10-27 [data set], CC BY 4.0, sourced 26 October 2026. Serialised and versioned by National Digital at publicdata.au. Available at: https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/ Markdown: Data: [AIHW MyHospitals](https://www.aihw.gov.au/copyright), Australian Institute of Health and Welfare, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), sourced 26 October 2026. Files: [publicdata.au](https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/) by [National Digital](https://nationaldigital.com.au/). ## Questions ### How do I download Emergency department patients who left within four hours by hospital and patient group as a CSV file? Open https://publicdata.au/d/au-ed-time-within-4-hours/latest/data.csv. It redirects to the newest dated version, which is https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/data.csv today. The same path serves Excel, JSON, Parquet, SQLite, DuckDB, NDJSON. A dated URL never changes, so use it when the file must stay the same. ### Can I open Emergency department patients who left within four hours by hospital and patient group in Excel? Yes. https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/data.xlsx is a workbook with the 36,289 rows on a records sheet, the field list on a second sheet and the provenance on a third. The CSV also opens in Excel. https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/data.csv.gz is the CSV at about a tenth of the size. ### What years does Emergency department patients who left within four hours by hospital and patient group cover? The current version covers the years since 2011. Each release from AIHW becomes a new dated version here, and earlier versions stay online. ### How often is Emergency department patients who left within four hours by hospital and patient group updated? AIHW releases it several times a year. This site checks the portal every week and adds a dated version when the file changes. ### Can I use Emergency department patients who left within four hours by hospital and patient group commercially? Yes. CC BY 4.0 allows commercial use, redistribution and derived works as long as the attribution is kept. The attribution string is in this page's side column and inside every file. ### Is this the official source for Emergency department patients who left within four hours by hospital and patient group? No. The publisher is Australian Institute of Health and Welfare, and its page is https://www.aihw.gov.au/copyright. National Digital converted the publisher's file to other formats. It renamed and typed the columns and kept only those the schema lists. It made each suppressed value a null with a flag. It kept the publisher's marker for each empty cell in a markers column. National Digital made these changes, and the publisher is not responsible for them. The original sits beside every version as source.xlsx with its SHA-256, so the two can be compared. ### How do I get only the rows for one state? Every version has one JSON file per value of `state`, 9 files in the current version, listed with row counts at https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/by/state/index.json. For example https://publicdata.au/d/au-ed-time-within-4-hours/v/2026-10-27/by/state/nsw.json holds the 19,472 rows where `state` is `NSW`. ### What is in each row? One public hospital, Local Hospital Network, state or the nation, one financial year from 2011-12 and one patient group. It gives the number of emergency presentations and the share of patients who left the emergency department within four hours of arriving, beside the average for the hospital's peer group. ### Which patient groups are there? The Institute gives all patients, patients admitted from the emergency department to the same hospital, patients not admitted, and each of the five triage categories. The share is a fraction, so 0.8 means 80 per cent. ### What do the blanks mean? The Institute writes `<5` for a count under five, `NP` where the data did not meet its criteria to calculate the figure and `NP†` where more than 10 per cent of presentations had missing or invalid time data. Those cells are null here with a suppressed flag. A dash, meaning no patients were reported, and Not peered are null. The markers column keeps each code. The Institute's file also marks with an asterisk the figures to interpret with caution, in a column with no heading, which is not carried here. ## What this site did to the data Cells were typed, headers were renamed to snake_case and the encoding was made UTF-8. Rows were left alone. Nothing is derived. The publisher's file is beside every version as `source.xlsx`. ## Improve this dataset This page is built from [register/au-ed-time-within-4-hours.yaml](https://github.com/National-Digital/publicdata.au/blob/main/register/au-ed-time-within-4-hours.yaml) on GitHub, and a fix to it is welcome as a pull request. https://publicdata.au/contribute/ explains how.