Hospital Inpatient and Outpatient Data

Hospitals must file with the MHDO a completed hospital inpatient and outpatient data set for every service provided to each patient. See Rule Chapter 241 on our Rules and Statutes page for a complete definition of the data which must be submitted, and by which hospitals.

For those involved with or impacted by the development and implementation of our new hospital data submission system and testing the addition of ICD-10 fields, please see the Hospital Data Submitters page.

Available Datasets

The elements available in the various data sets can be reviewed in the document Hospital Encounter Release Elements.
In addition you may review the specific set of validations the hospital data are measured against before the MHDO accepts into our database.
If you are interested in requesting data, our Request Data or Reports page has all the information you need.

Recent Releases

Note: Expected release dates of hospital inpatient and outpatient encounter data can be found on our Data Release Schedules page.

12/1/17 2017 Q1 & Q2 Inpatient Hospital Encounter Data Released

The following information was provided to the users as part of the release.

Hospital Encounter FAQ's (updated)

Note ID Release Version Note Text Start Data Year End Data Year
5 6 This release contains January-June (Q1 & Q2) 2017 Hospital Inpatient Encounter data.
It contains inpatient encounter data for all Maine hospitals required to submit according to
Chapter 241 and there are no data quality issues to note.
1/1/2017 6/30/2017
6/30/17 2016 Outpatient Hospital Encounter Data Released today

The following documents were provided to users as part of the release.

6/13/17 2016 Inpatient Hospital Encounter Data Released 6/13/17

The following documents were provided to users as part of the release.

4/21/17 2015 Outpatient Hospital Encounter Data Released 4/21/17

The following documents were provided to users as part of the release.

3/20/17 2015 Inpatient Hospital Encounter Data Released 3/17/17

The following documents were provided to users as part of the release.

5/2/16 2014 Inpatient and Oupatient Hospital Encounter Data Released 4/29/16

The following documents were provided to users as part of the release.

Update 4/11/16 2013 Outpatient Data Released on 3/11/16: See the 2013 Hospital Outpatient Data Release Notes

Update 4/11/16 2012 Hospital Data and 2013 Inpatient Hospital Data Refresh

On 3/11/16 MHDO released a refresh of the 2012 Inpatient and Outpatient data and of the 2013 Inpatient data.

The refresh release notes are below.

Update 12/4/15 Corrections/Clarifications to the release notes for 2012 hospital inpatient and outpatient, and 2013 inpatient data were made available. The release documentation is available upon request. Call 207 287-6722 or email

11/4/15 Data Release: 2012 Inpatient, 2012 Outpatient, and 2013 Inpatient Data Were Released

Information Regarding 2012 Outpatient Data Release of 8/15/14:

In spite of the extensive internal and external QC that is performed on data prior to release, an issue involving duplicate records has only now been uncovered in the Maine 2012 Outpatient data which was released in August of 2014. In total, there were 49,985 records that appear more than once, most often under two different hospitals. This represents 0.8% of the total release data.

The duplicate system ID file contains a list of record ID (Sysid) that need to be removed from the release data to correct for this error. Any record on either the Encounter or Detail table that has a Sysid on the list should be removed from any analysis of the data.

Removing these records from the previously sent data seems to be the most expedient way to resolve this issue, as users will have already loaded the data into their systems. Any user that would prefer to receive a complete replacement of the release files should contact the MHDO.

Going forward an additional check will be added to the internal QC process to identify and remove any exact duplicate records prior to release.

If you have any questions or concerns, please contact Karynlee Harrington at 207-446-0890.

Outpatient Hospital Encounter Data for CY 2012 were released 8/15/2014. As we continue to work on improving our documentation we provided users with several documents as part of the release.