Hospital Discharge Data Documentation
DefinitionsAn inpatient hospitalization is one in which the patient was admitted to the hospital directly or through the emergency department or other department.
The Emergency Department Database contains information on ED visits that do not result in admission to the same hospital (i.e., "treated and released," which includes patients who were discharged home, transferred to another health care facility, left against medical advice, left without being seen, transferred to another hospital, or died).
Outpatient and same-day surgery are scheduled in-hospital surgery and the patient is not admitted to the hospital.
Sources of Data
Hospital DischargesThe New Jersey Discharge Data Collection System (NJDDCS) database, modeled under the Uniform Billing (UB) database is the data used for the hospitalization query. The NJDDCS is managed by the Office of Health Care Quality Assessment (HCQA) in the New Jersey Department of Health. The NJDDCS contains information on demographic characteristics of patients, diagnosis and procedure codes following the International Classification of Diseases (ICD), and billing information and charges for services provided.
HCQA receives patient-level hospital discharge data on emergency department (ED), outpatient surgery, same-day surgery and inpatient encounters or episodes. The Inpatient Hospital Discharge Query only contains discharges in which the person had been admitted to the hospital. The Emergency Department Query only contains visits in which the person was discharged from the ED. If the person is admitted to the hospital from the ED, their record is in the Inpatient Hospitalization part of the query.
PopulationPopulation estimates used to calculate discharge rates are derived from the most recent vintage of the mid-year estimates provided by the Population Division of the U.S. Bureau of the Census. These estimates are based on the 2000 Census with 31 race categories aggregated to the following race groups: White alone, Black alone, American Indian/ Alaska Native alone, Asian alone, Native Hawaiian/Pacific Islander alone, and Two or more races. Estimates are available for each state and its counties by age, race, Hispanic ethnicity, and sex categories. Race and ethnicity can be combined to form seven race/ethnicity groups, where Hispanics may be of any race, the other six groups do not include Hispanics, and data for White, Black, Asian, Native Hawaiian/Pacific Islander, and American Indian/Alaska Native are counts of persons who only selected one of those races (i.e., "alone").
There are separate queries for state and county rates because two different sets of population data are used as denominators in the rate calculations. Population estimates for the state are available by single year of age while estimates for counties are only available in 5-year age groups.
Quality of DataHCQA receives patient-level hospital discharge data on a monthly basis through its data intermediary. Each record is subjected to a series of edits that check for accuracy, consistency, completeness, and conformity with the definitions specified in the New Jersey Discharge Data Collection System. Records failing the edit check are returned to the hospital for corrections and resubmission.
Allocation of Data by Residence or OccurrenceFor public health planning and policy determination, the most useful population to study is usually the resident population of an area. Although there are limited hospitalization data exchange agreements among neighboring states, the NJDDCS does not contain hospitalizations that occurred out of state. The query system provides data only on hospital encounters of New Jersey residents that occurred in New Jersey hospitals and does not fully capture all hospitalizations of New Jersey residents.
Allocation of data by place of residence within the state is sometimes difficult because classification depends on the statement of the usual place of residence provided at the time of hospitalization. For a variety of reasons, the information provided may be incorrectly recorded. Another common problem occurs when patients use mailing address for residence address. Currently, there is no mechanism implemented to correct hospitalization data files by running them through geocoding software to properly assign the county and municipality of residence. The place of residence information should be used with caution.
Race and EthnicityA race group (White, Black/African American, American Indian/Alaska Native, Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese, Other Asian, Native Hawaiian, Guamian/Chamorro, Samoan, Other Pacific Islander, Multiracial: White and Black/African American, Multiracial: White and American Indian/Alaska Native, Multiracial: White and Asian, Multiracial: Black/African American and American Indian/Alaska Native, Other Race, Unknown/Unavailable, and Declined to Answer) and an ethnicity (Non-Hispanic, Mexican, Puerto Rican, Cuban, Central or South American, other Hispanic, Unknown/Unavailable and Declined to Answer) are recorded for each individual for whom a hospitalization record is filed. In order to standardize reporting, race and ethnicity categories are used together to create mutually exclusive categories including a Hispanic "race" category as is customary in reporting such data by the New Jersey Department of Health.
Race/ethnicity designations used in the hospitalization query are White, Black, Hispanic, Asian, Native Hawaiian/Other Pacific Islander, American Indian/Alaska Native, Two or More Races, and Other Race, where Hispanics may be of any race and the other race groups do not include Hispanics (but include those with ethnicity unknown). The Hispanic category includes persons of Mexican, Puerto Rican, Cuban, Central/South American, or other Hispanic ethnicity, regardless of race. The Asian category includes persons of Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese, and other Asian descent. The Native Hawaiian/Other Pacific Islander category includes persons of Hawaiian, Guamian, Samoan, and other Pacific Islander descent. The Two of More Races category includes all four multiracial categories. The Other Race category includes all race groups other than White, Black, Asian, Native Hawaiian/Pacific Islander, American Indian/Alaska Native, and the four Multiracial groups. When combining race and ethnicity, Hispanic ethnicity takes precedence over whatever race is recorded for the patient.