- The Birth Data dataset is derived from the information collected by the Massachusetts Department of Public Health to complete a birth certificate. A Massachusetts birth certificate is recorded for every child born to a mother living in Massachusetts. This dataset includes information relating only to births in Boston. - The data to complete the birth certificate is provided by hospital personnel and the child's parents. - Race and ethnicity are generally a matter of self-identification, that is, individuals choose the racial or ethnic group with which they identify. - At times, a parent may not be able to provide the information themselves; in that case the hospital employee working with the family may make a determination based on their best estimate or guess. - Census Tracts containing five or fewer births are reported as 2 in this dataset. - This dataset covers 20047 births of babies by mothers living in Boston during 1990-1991. - Level of aggregation: 1970 Census Tracts all other files conform to the 1990 Census Tracts.