Release notes

The MIMIC-III database will be periodically updated as more data becomes available, as data linkage and extraction methods improve, and when the community provides feedback regarding the database content. To ensure transparency in this process, updates to the database will be made in batch, and the version number of the MIMIC-III database will be updated. This page lists the current version, and all previous versions which have existed, in sequential, reverse chronological order. Each version will address a finite set of updates which are tracked using a unique issue number, usually of the form #100, #101, etc.

Note that the changes between MIMIC-II and MIMIC-III are not listed here, due to the large number of differences between the databases. A separate document has been provided for that purpose here. The release notes for MIMIC-II versions is available here.

Current version

The current version of the database is v1.4. When referencing this version, we recommend using the full title: MIMIC-III v1.4.


MIMIC-III v1.4 was released on 2 September 2016. It was a major release enhancing data quality and providing a large amount of additional data for Metavision patients.

Issues addressed include:

  • #88 - Text data sourced from drop down menus or “pick lists” has been added to the database for Metavision patients. Users interested in the exact concepts added can query them as follows:
    select * from d_items
    where linksto = 'chartevents'
    and dbsource = 'metavision'
    and param_type = 'Text'.
    All data was added to the chartevents table, increasing the raw (uncompressed) size of the datafile by 5 GB.
  • #201 - Data in tables may now only occur within 1 year of a patient’s hospital admission admittime and dischtime. Observations outside this range corresponded to typographical errors in the charttime, and this unreliable data has been removed.
  • #197 - A small issue where a single observation was duplicated and assigned to two icustay_id (and sometimes two hadm_id) has been corrected: this affected 37 icustay_id and 80 hadm_id. Thanks @matteobonvini on GitHub for the report.
  • #191 - A subset of patients were missing data due to the transition from CareVue to Metavision: this data has been restored.
  • #193 - Some laboratory concepts (particularly CD counts) were conflated (i.e. percentages mixed with counts) - these have been corrected. Thanks Yuqi Si for the report (via StackExchange).
  • #196 - The amount column in inputevents_mv did not correspond to amountuom (unit of measurement) - instead it corresponded to a “base” unit (e.g. grams instead of milligrams). Data in the amount has been updated to match the amountuom where appropriate. This also effected the procedureevents_mv table. Thanks @ngageorange on GitHub for the report.
  • #198 - NULL values for character fields are now properly represented in the CSV file as empty fields with no double quotes. Database systems such as PostgreSQL will now recognize these fields as null when copying with the NULL “ qualifier.
  • #199 - Addendums to discharge summaries in the notes can now be distinguished in the noteevents table: their category has remained ‘Discharge summary’, but their description has been changed from ‘Report’ to ‘Addendum’
  • #194 - The LOINC code for Total CO2 has been corrected (was 1959-6 total bicarb, is now 34728-6 total CO2)
  • #186 - Data has been harmonized into EST.
  • #180 - Some patients were erroneously labelled as in care unit ‘TSICU’: these have been corrected to ‘CSRU’
  • #189 - Schema change: The has_ioevents_data column in admissions has been removed as it was no longer meaningful.
  • #185 - Three text concepts (GCS, code status, RASS) had a null linksto field in d_items, even though the data existed in chartevents. This has been corrected. Note these were the only three text concepts available for Metavision patients in MIMIC-III v1.3 (see #88).
  • #60 - The date shift for dates in the text field of noteevents has been corrected: before it corresponded to a different date shifted used in MIMIC-II (easily identifiable by years occurring between 2500-3500). It now matches the dates in the structured data.
  • #188 - Negative microbiology cultures are now recorded in micriobiologyevents - negative cultures can be identified by a NULL value for the organism name (org_name).

Be sure to validate the checksum of the resultant file to ensure you have the correct version.

Past versions

This section lists past versions in reverse chronological order.


MIMIC-III v1.3 was released on 10 December 2015. It was a minor release enhancing the consistency of the dataset.

Issues addressed include:

  • #175 - A new value for DRG_VERSION was added to the DRGCODES table to clarify why the same code matched to multiple descriptions.
  • #174 - The EDTIMEOUT column was renamed to EDOUTTIME in the ADMISSIONS table for consistency with other timestamp columns.
  • #173 - The UOM column was renamed to VALUEUOM in the CHARTEVENTS, DATETIMEEVENTS, and LABEVENTS tables for consistency with other UOM columns.
  • #172, #177 - Several careunit acronyms were merged in the TRANSFERS and ICUSTAYS tables for ease of interpretation.
  • #168 - A set of ITEMIDs in the INPUTEVENTS_CV table were inappropriately low (<30000), they have no been corrected.
  • #167 - Duplicate radiology reports were removed from the NOTEEVENTS table. These duplicates were present in the raw data.
  • #166 - The DBSOURCE column was corrected from Metavision to CareVue for a set of patients in the TRANSFERS and ICUSTAYS tables.


MIMIC-III v1.2 was released on 10 November 2015. MIMIC-III v1.2 was a major release providing both bug fixes and a large amount of additional data.

Major issues addressed, including additional data made available:

  • #130 and #135 - Duplicate data in various events tables with CGID has been removed
  • #132 - Hospital expire flag was in the wrong table - now moved to ADMISSIONS table. EXPIRE_FLAG added to PATIENTS table.
  • #137 - The ITEMID for input/output items has been properly shifted to range between 30000-40000. Previously it incorrectly ranged between 1-5000, and as a result did not match the dictionary entries in D_ITEMS.
  • #141 - CHARTTIME and STORETIME have been added to NOTEEVENTS, if available. No times were available for ECG and echo reports (only the date).
  • #144 - Dates of birth for patients > 89 are now shifted by 300 years for clarity.
  • #151 - The time of emergency department registration and exit has been added to the admissions table, where available.
  • #154 - A new table, PROCEDUREEVENTS_MV, has been added. This table contains information regarding the start and stop time for various procedures for Metavision patients. Procedures include x-rays, ventilation, dialysis, and others.
  • #158 - The IOEVENTS table has been split into three tables: INPUTEVENTS_CV (CareVue patients only), INPUTEVENTS_MV (Metavision patients only), and OUTPUTEVENTS (all patients).
  • #162 - 5,795,842 rows of data corresponding to yes/no answers have been added for Metavision patients
  • #164 - 10,140 rows of “Non Iv meds” (e.g. vancomycin) have been added for Metavision patients

Minor issues addressed:

  • #126 - ROW_ID, CGID, ORDERID and LINKORDERID now stored as INT instead of BIGINT
  • #134 - The CR/LF characters which prefixed notes in NOTEEVENTS have been removed
  • #136 - The VOLUME column in the events tables for inputs has been changed to AMOUNT
  • #139 - The units for certain solution volumes, erroneously recorded as rate units, have been corrected
  • #140 - The ORIGINALAMOUNT column no longer exists for rows with drug rates, only with drug volumes
  • #148 - Removed RECORD_ID from NOTEEVENTS as it was redundant
  • #149 - ICUSTAYEVENTS has been renamed ICUSTAYS
  • #152 - The STARTTIME and ENDTIME columns have been renamed STARTDATE and ENDDATE for the PRESCRIPTIONS table to reflect the lack of time information.
  • #155 - LINKSTO column in D_ITEMS has been corrected: now correctly refers to PROCEDUREEVENTS_MV, INPUTEVENTS_MV, INPUTEVENTS_CV, and OUTPUTEVENTS.
  • #156 - The SEQUENCE column in DIAGNOSES_ICD and PROCEDURES_ICD has been renamed SEQ_NUM.
  • #159 - A CONCEPTID column has been added to D_ITEMS for future ontology mapping/data harmonization.
  • #163 - The CODE column has been removed from MICROBIOLOGYEVENTS and D_ITEMS as it was redundant to ITEMID


MIMIC-III v1.1 was released on 24 September 2015. It was primarily a bug fix release, and addresses the following issues:

  • #116 - CGID was incorrect in the DATETIMEEVENTS, CHARTEVENTS, IOEVENTS and NOTEEVENTS tables. It has now been corrected.
  • #117 - VALUENUM for GCS verbal response measurements has been corrected for Metavision (it was offset by -1).
  • #118 - VALUENUM for all GCS measurements in CareVue is no longer null, and contains the appropriate value in the scale.
  • #120 - DOD was incorrectly set to DOB - this has been fixed.
  • #121 - IOEVENTS contained incorrect units for certain drugs (sometimes the unit was a rate when the actual observation was an amount, e.g. listed as “mcgkgmin” when it should have been “mg”).
  • #122 - DBSOURCE in the TRANSFERS and ICUSTAYEVENTS tables has been corrected - originally it only contained ‘metavision’ when a patient was in the ICU, so the same patient would be listed as ‘carevue’ when out of the ICU and ‘metavision’ when inside the ICU.
  • #123 - Precision in the IOEVENTS table has been fixed at 10 decimal places.


MIMIC-III v1.0 was released on 25 August 2015. It was a preliminary version and not widely publicized to allow for internal testing. As this was the first release of the database, and the successor of the MIMIC-II database, no changes are listed here. An overview of changes between MIMIC-II and MIMIC-III is provided here.

MIMIC-III v1.4 documentation