Types of OSHPD Patient-Level Data

Patient Discharge Data (PDD)

The Patient Discharge Data set consists of a record for each inpatient discharge from a California-licensed hospital. Licensed hospitals include general acute care, acute psychiatric, chemical dependency recovery, and psychiatric health facilities. For more information on the data and reporting requirements, see the California Inpatient Data Reporting Manual. These data sets are available starting in 1983.

For detailed information about the data elements within the PDD, view the data dictionaries on the Data Documentation page.

Emergency Department Data (ED)

The emergency department data set includes demographic, clinical, payer, and facility information from hospitals licensed to provide emergency medical services. The ED encounters include those patients who had face-to-face contact with the provider. In the event that the patient left without being seen, the patient would not have had a face-to-face encounter with a provider and therefore the ED encounter would not be reported. A provider is defined as the person who has primary responsibility for assessing and treating the condition of a patient at a given contact and exercises independent judgment in the care of the patient. Providers include medical doctors, doctors of osteopathy, doctors of dental surgery, or doctors of podiatric medicine. If the ED encounter resulted in a same-hospital admission, the ED encounter would be combined with the inpatient record and a separate ED record would not be reported. When analyzing ED records, you may want to include the records identified in the inpatient database as having the hospital’s own ED as the source of admission. For more information on the data and reporting requirements, see the California Emergency Department and Ambulatory Surgery Data Reporting Manual. These data sets are available beginning January 2005.

For detailed information about the data elements within the ED, view the data dictionaries on the Data Documentation page.

Ambulatory Surgery Center Data (AS)

The ambulatory surgery data set includes encounters from general acute care hospitals and licensed freestanding Ambulatory Surgery Centers, during which at least one ambulatory surgery procedure is performed. A freestanding ambulatory surgery clinic is defined as a surgical clinic licensed by the California Department of Public Health (CDPH). Many facilities that are called ambulatory surgery centers are not required to be licensed as surgical clinics, and do not report data to the Office. An ambulatory surgery procedure is defined as those procedures performed on an outpatient basis in the general operating rooms, ambulatory surgery rooms, endoscopy units, or cardiac catheterization laboratories of a hospital or a freestanding ambulatory surgery clinic. If a procedure was done elsewhere (such as in a radiology unit), no ambulatory surgery record is required to be filed. If a hospital-based AS encounter resulted in a same-hospital admission, the AS encounter would be combined with the inpatient record and a separate AS record would not be reported. When analyzing hospital-based AS records, you may want to include AS direct admissions, which are identified in the hospital’s inpatient data as having Ambulatory Surgery at the same hospital as the source of admission. For more information on the data and reporting requirements, see the California Emergency Department and Ambulatory Surgery Data Reporting Manual. These data sets are available beginning January 2005.

For detailed information about the data elements within the AS, view the data dictionaries on the Data Documentation page.

Linked Files – Birth and Death Data

The OSHPD patient record-level data is linked with the Vital Statistics Birth Statistical Master File, Birth Cohort File and Death Statistical Master Files. The vital statistics files themselves are available from the California Department of Public Health at the Vital Statistics Data Web site. The linked data files are available to qualified researchers through requests submitted to OSHPD.

Linked Birth File

The Linked Birth File is a research database created for the purpose of studying delivery and birth outcomes. This linkage utilizes information from the following data sets:

  • California Patient Discharge Data
  • Vital Statistics Birth Certificate Data
  • Vital Statistics Death Certificate Data
  • Vital Statistics Fetal Death File
  • Vital Statistics Birth Cohort File

It includes maternal antepartum and postpartum hospital records for the nine months prior to delivery and one-year post delivery. In addition, the linked file includes birth records and all infant readmissions occurring within the first year of life. The linked pairs of birth/delivery records include information associated with a mother/baby pair from the baby’s discharge data record, the mother’s discharge data record, and the birth certificate data. All associated records (prenatal, postnatal, transfers and infant readmissions) are identified by the variable _BRTHID and are sorted in admission date order.

The file contains all infants that were born in a given year including births that occurred in a California hospital that report to OSHPD, births that occurred in a California hospital that did not report to OSHPD, and births that occurred outside California. It includes all infants and mothers irrespective of whether they were linked to a birth record or not. Linked Birth files are available to qualified researchers beginning with the 1991 calendar year reporting period. See the Master Variable Grid for available years. Note: The most recent year may not be a full cohort file depending on availability of the input cohort file.

Linked Death File

OSHPD has developed validated research data sets linking patient data with the state death statistical master file. These data sets allow researchers to track mortality outcomes within and outside of the hospital.

Probabilistic Linked Death File

This data file provides a unique best match of a single death record to a patient’s last identifiable record in the Patient Discharge Data. Two versions of the probabilistic Linked Death file are available beginning with calendar year 1990.

Probabilistic Linked Death File
  • Version A - Death records are linked to the last PDD discharge record, regardless of type of care.
  • Version B - Death records are linked to the last PDD discharge record for acute type of care.
Deterministic Linked Death File

The deterministic linkage, available beginning with calendar year 2005, links the state death statistical master file to the PDD, ED, and AS files. Requesting all 3 files can provide mortality outcomes for any inpatient, emergency department, or licensed ambulatory surgery care setting.

Coronary Artery Bypass Graft (CABG) Data

The Coronary Artery Bypass Graft (CABG) File is a research database created for the purpose of studying outcomes related to the most common surgical procedure for treating coronary artery disease. In this surgery, a vein or artery from another part of the body is used to create a new path for blood to flow to the heart, bypassing the blocked artery. Coronary artery disease is the leading cause of all adult non-maternal admissions to California hospitals, representing nearly 9% of all admissions. CABG data is collected from California-licensed hospitals where surgeons performed isolated CABG surgery, via the California Coronary Artery Bypass Graft (CABG) Outcomes Reporting Program (CCORP). The data is analyzed for quality of care reporting purposes, in compliance with California Health and Safety Code Sections 128745-128750. Data from the California Coronary Artery Bypass Graft (CABG) Outcomes Reporting Program (CCORP) are available for research purposes, subject to review and approval by OSHPD. CABG files are available to qualified researchers beginning with the 2006 calendar year. See the Master Variable Grid for available years.


This page was last updated on Friday, January 27, 2017.

Data Years Available
  PDD ED/AS
PUF 2010-2014 2010-2014
AB 2876 1983-2016 2005-2016
IPA 1983-2016 2005-2016
Custom 1983-2016 2005-2016

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