All data in the birth query pertain to live births to New Jersey resident mothers regardless of where the birth occurred. A live birth is defined as the complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of pregnancy, which, after such separation, breathes or shows any evidence of life, such as beating of the heart, pulsation of the umbilical cord, or definite movement of voluntary muscles. The vital statistics term for stillbirths is fetal deaths and they are not included in the birth query.

Births

The birth certificate is the source document for data included in the birth query. New Jersey law requires that the attending physician, midwife, or person acting as midwife file a certificate of birth with the Local Registrar within five days of a birth within the state. Birth records are filed electronically by hospitals, birthing centers, and midwives who attend home births. Medical records staff use standard mother and facility worksheets and medical charts to complete the birth registration. Training is provided by the Office of Vital Statistics and Registry (OVSR). The electronic birth registration system has online edits and records are reviewed by OVSR and the Center for Health Statistics (CHS). Additionally, the National Center for Health Statistics (NCHS) provides feedback to OVSR on data quality. OVSR also provides feedback to hospitals to improve data quality and contacts hospital staff for clarification of missing, inconsistent, or incorrect entries. The data included in the query are for New Jersey residents regardless of where the birth occurred. The inclusion of statistics on births to New Jersey residents which occurred in other states is made possible through the Vital Statistics Cooperative Program (VSCP) with NCHS and Inter-Jurisdictional Exchange (IJE) agreement between states, which encourage the exchange of information on vital events between the states of occurrence and residence.

The birth data in the query system were generated from data files available at the time of preparation of the back-end dataset. Any data pertaining to a birth for which a certificate was filed after that time or relating to corrections or revisions made since the data were processed for the electronic file are not included. Vital events computer files are periodically updated by OVSR and CHS staff based on correction reports received from local registrars and from data quality control analyses conducted by CHS. The query incorporates data from the most recently updated files.

Data Collection System Changes Over Time

• In 1990, where NJSHAD birth data begins, all birth certificate information was collected on paper and keyed into a computer database by New Jersey Department of Health staff.
• New Jersey's first electronic birth registration system, called the Electronic Birth Certificate (EBC), was piloted in 1996 and installed in all birthing facilites by the end of 1998. The EBC allowed for the collection of more information than ever before.
• 2014 and 2015 were transitional years in New Jersey birth data collection as the old EBC system was retired and the new Vital Information Platform (VIP) was rolled out in hospitals across the state over a one year period from July 2014 through June 2015. Several birth certificate items were collected differently in the VIP than they were in the EBC and are not directly comparable, therefore all data for those items that were collected through the VIP are shown as Unknown in those years.
• 2021 was another transitional year as VIP was replaced by the Vital Event Registry Information for New Jersey (VERI-NJ) system from mid-July through mid-August 2021. The Center for Health Statistics backcoded 2021 records collected in VERI-NJ to the VIP format and 2022 was the first year of data completely collected through VERI-NJ.

Population

Population estimates used to calculate state and county birth and fertility rates were derived from the Bridged-race intercensal population estimates for 1990-1999 and 2000-2009 and Vintage 2020 Bridged-race postcensal population estimates for 2010-2019 prepared by NCHS in collaboration with the U.S. Census Bureau. These estimates resulted from bridging the 31 race categories used in the 2000 Census, as specified in the 1997 federal OMB standards for the collection of data on race and ethnicity, to the four race categories specified under the 1977 standards.  Many data systems, including birth statistics, continued to use the 1977 standards during the transition to full implementation of the 1997 standards. Estimates were developed for each state and its counties by five-year age groups, sex, Hispanic ethnicity, and four race groups (White, Black, Asian and Pacific Islander, and American Indian and Alaska Native).

Population estimates used to calculate state and county birth and fertility rates for 2020 onward were derived from the most recent vintage of postcensal population estimates from the U.S. Census Bureau.

Municipality population estimates by age and sex are statistically unreliable for all but the largest municipalities, therefore fertility rates are not provided at the municipal level. Municipality population estimates used to calculate birth rates are provided by the New Jersey Department of Labor and Workforce Development's State Data Center.

The reporting of births is considered to be essentially complete. According to the National Center for Health Statistics (NCHS), more than 99% of births are registered. The completeness of reporting by residence is dependent on the effective functioning of the interstate data exchange program for certificates which is fostered and encouraged by NCHS and the National Association for Public Health Statistics and Information Systems (NAPHSIS). Research has shown that there is some degree of slippage in receiving information on all births of New Jersey residents occurring in other states. However, the number of missing events is thought to be small, relative to the overall number of births.

The quality of the data included in the query is a function of the accuracy and completeness of the information recorded in the respective electronic systems and of the quality control procedures employed in the coding and keying processes. A query program in which the individual(s) responsible for completing the certificate data entry is questioned about missing or conflicting information is carried out by OVSR staff. This process is augmented by the data quality control analyses performed by CHS using all of the NCHS edit criteria.

Alcohol, tobacco, and drug use during pregnancy are self-reported by the mother and thus should be interpreted with caution. Reporting of drug use during pregnancy was incomplete before 1996, therefore all maternal drug use data for 1990-1995 are shown as Unknown. Health insurance information and type of feeding at the time of discharge were not collected with birth certificate data prior to 1997, therefore all Medicaid status and infant feeding data for 1990-1996 are shown as Unknown. New birth data collection standards began in 2014 and eliminated our ability to report maternal drug and alcohol use during pregnancy, so those items are again shown as Unknown for all years after 2013.

For public health planning and policy determination, the most useful population to study is usually the resident population of an area. In the case of births, the existence of resident certificate exchange agreements among the registration areas in the country permits analysis of resident birth statistics regardless of where the birth occurred. In the query system, the data presented represent births to New Jersey resident mothers, regardless of where the birth occurred. Births that occurred in New Jersey to non-NJ residents are not included.

Allocation of births by place of residence within the state is sometimes difficult because classification depends on the statement of the usual place of residence provided by the informant at the time the certificate is completed. For a variety of reasons, the information given may be incorrectly recorded. A common source of error is the confusion of mailing address with residence address. For this reason, all records are run through geocoding software to properly assign the county and municipality of residence.

Race and ethnicity of the child are not recorded on birth certificates and that of the mother is used for statistical analysis.

Race and Ethnicity (separately)

Prior to 2014, one race group (White, Black, American Indian/Alaska Native, Chinese, Japanese, Hawaiian, Filipino, Asian Indian, Korean, Samoan, Vietnamese, Guamanian, other Asian/Pacific Islander, other race, and an unknown race category) and an ethnicity (Non-Hispanic, Mexican, Puerto Rican, Cuban, Central or South American, other Hispanic, and an unknown ethnicity category) were recorded for each parent of each individual for whom a birth certificate was filed in New Jersey.

Beginning in 2014, two or more races could be selected for each parent on New Jersey birth certificates.

• One or more of the following may be used to describe the race of the parent: White, Black, American Indian/Alaska Native, Chinese, Japanese, Filipino, Asian Indian, Korean, Vietnamese, other Asian, Native Hawaiian, Samoan, Guamanian/Chamorro, other Pacific Islander, other race, and an unknown race category.
• An ethnicity (Non-Hispanic, Cuban, Mexican, Puerto Rican, other Hispanic, and an unknown ethnicity category) is also recorded for each parent of each individual for whom a birth certificate is filed.

Race/Ethnicity (combined)

Race and ethnicity can be combined to make a Hispanic "race" group and this is the standard way the New Jersey Department of Health reports birth data. When combining race and ethnicity, Hispanic ethnicity takes precedence over whatever race or races are recorded.

Birth and Fertility Rates

Due to the limitations of the corresponding population data as well as birth records for New Jersey resident births that occured in states that had not yet adopted the new race and ethnicity standards, race/ethnicity designations used in the 1990-2019 birth and fertility rate query modules are White, Black, Hispanic, Asian/Pacific Islander, and American Indian/Alaska Native, where Hispanics may be of any race and the other race groups do not include Hispanics (but include those with ethnicity not stated).

• The Hispanic category includes persons of Mexican, Puerto Rican, Cuban, Central/South American, or other Hispanic ethnicity, regardless of race.
• The Asian/Pacific Islander category includes persons of Chinese, Japanese, Hawaiian, Filipino, Asian Indian, Korean, Samoan, Vietnamese, Guamanian, and other Asian and Pacific Islander descent who were not reported as Hispanic.

By 2020, all vital statistics jurisdictions allowed more than one race to be selected on birth records, so race/ethnicity designations in the birth and fertility rate query modules going forward are White, Black, Hispanic, Asian, Native Hawaiian/Pacific Islander, American Indian/Alaska Native, Other Single Race, and Two or More Races, where Hispanics may be of any race and the other race groups do not include Hispanics (but include those with ethnicity not stated).

• The Hispanic category includes persons of Mexican, Puerto Rican, Cuban, or other Hispanic ethnicity, regardless of race.
• The Asian category includes persons of Chinese, Japanese, Filipino, Asian Indian, Korean, Vietnamese, and other Asian descent who were not reported as Hispanic.
• The Native Hawaiian/Pacific Islander category includes persons of Hawaiian, Samoan, Guamanian/Chamorro, and other Pacific Islander descent who were not reported as Hispanic.
• The Other Single Race category includes all race groups other than those mentioned above who were not reported as Hispanic. (There are no corresponding population estimates for this group, so rates are not available.)
• The Two or More Races category includes persons who self-identified as more than one race and who were not reported as Hispanic.

Nativity (Birthplace)

Three nativity categories are used in the query: U.S. States and D.C., U.S. Territories, and Remainder of World. Remainder of World (i.e., foreign-born) includes mothers born anywhere other than the 50 states, the District of Columbia, and the 5 inhabited U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and Northern Marianas).

• Prior to 2014, American Samoa and the Northern Marianas were not coded separately in the electronic birth files and were included in foreign-born.
• Foreign-born also includes those born abroad to American parents because birth certificates do not have an item to distinguish those cases. Numbers of births to New Jersey residents born abroad to American parents are extremely small.

The presentation of birth and fertility rates facilitates comparisons between political subdivisions with populations of different sizes or between subgroups of a population. Crude birth rates are calculated by dividing the number of births to the residents of an area by the resident population of an area or subgroup and are usually expressed per 1,000 residents. Births are limited to those that occur within a specific time period, usually a year, and the population is, in general, the mid-year estimate of the resident population of the area. Fertility, general fertility, and total fertility rates are calculated by dividing the number of births to the residents of an area or demographic subgroup by the female population of that area or subgroup, usually in a specified age range, such as 15-44 years.

In order to compare birth experiences among various ages and races/ethnicities, birth and fertility rates may be computed for subgroups of the population. These are referred to as age- or race/ethnicity-specific rates and are calculated by dividing the number of births within a subgroup by the population in the subgroup.

The definitions of rates used in the query system are on the Definitions of Public Health Terms and Acronyms page. It should be noted that alternative forms exist for some of these statistics. Some other states and the federal government may employ different formulae for the computation of selected rates.

Caution should be exercised in the interpretation of rates based on small numbers. Chance variations in the number of births occurring in sparsely populated areas can cause rates to fluctuate widely over time. In accordance with NCHS standards, rates based on fewer than 20 births or fewer than 20 persons in the population or with a relative standard error greater than 23% are considered unreliable for analysis purposes. Therefore, these rates are not displayed and are indicated by ** in the appropriate cell. For purposes of analyzing birth and fertility rates for small areas, calculation of three- or five-year average rates and other statistical methodologies for analyzing small numbers may provide more meaningful measures.