Introduction:
Population estimates for intercensal years are obtained from the Massachusetts Institute for Social and Economic Research (MISER). MISER uses four mutually exclusive race classifications: non-Hispanic white; non-Hispanic black; non-Hispanic Asian/Pacific Islander and American Indian; and Hispanic. These classifications are inconsistent with how the Massachusetts Department of Public Health (MDPH) classifies race when determining population for use as denominators in the calculation of rates. Therefore, a methodology was developed to calculate the population for total whites, total blacks, total Asian/Pacific Islanders, total American Indians and Hispanics. The best information available to date regarding the numbers of whites, blacks, Asian/Pacific Islanders, American Indians, and Hispanics comes from the 1990 US Census Modified Age Race Sex (MARS) file.
Goal:
To determine the number of Asian/Pacific Islanders, American Indians, white Hispanics, black Hispanics, Asian/Pacific Islander Hispanics, and American Indian Hispanics living in every town in Massachusetts by gender and five year age group for the calculation of rates.
Methods:
Assumption: the proportion in 1990 has remained the same in 199x
- Calculate the proportion of American Indians: Asian & Pacific Islanders & American Indians from the 1990 US Census for each town by gender and five year age group
- Number of American Indians / Number of Asian & Pacific Islanders + Number of American Indians
- Apply the town/gender/age specific proportion to the 1991-1997 population of Asian & Pacific Islanders & American Indians to calculate the number of American Indians.
- Number of Asian & Pacific Islanders and American Indians in 199x * proportion of American Indians: Asian & Pacific Islanders and American Indians)
- Subtract the number of American Indians calculated from step 2 from the combined Asian & Pacific Islanders and American Indians to obtain the number of Asian & Pacific Islanders in 199x. This step ensures a control total.
- For the town/age/gender cells for which no proportion can be calculated because the number of Asian & Pacific Islanders and American Indians =0, use the town total proportion.
- If a town does not have any Asian & Pacific Islanders or American Indians in 1990, but has at least one combined Asian & Pacific Islander and American Indian in 199x, then use the average of the town proportions in the contiguous towns to assign a proportion to the town in 199x.
- To assign Hispanics to a race category, calculate the proportion of Hispanics in 1990 who were white, black, Asian & Pacific Islander, and American Indian.
- White Hispanics / Total Hispanics
- Black Hispanics / Total Hispanics
- Asian/Pacific Islander Hispanics / Total Hispanics
- American Indian Hispanics / Total Hispanics
- Apply the proportion of black Hispanics, Asian & Pacific Islander Hispanics and American Indian Hispanics in 1990 to the number of Hispanics in 199x.
- Number of Hispanics*proportion of black Hispanics
- Number of Hispanics*proportion of Asian & Pacific Islander Hispanics
- Number of Hispanics*proportion of American Indian Hispanics)
- Subtract the number of black Hispanics + Asian/Pacific Islander Hispanics + American Indian
- Hispanics from the total number of Hispanics to obtain the number of white Hispanics.
- For the town/age/gender cells for which no proportion can be calculated because the number of Hispanics =0, use the town total proportion.)
- There were no towns which had zero Hispanics in 1990, but had greater than zero Hispanics in 199x. Therefore, it was not necessary to create a proportion for this scenario as it was for the Asian & Pacific Islanders and American Indians.
- Add the number of white Hispanics to the number of non-Hispanic whites, number of Hispanic blacks to non-Hispanic blacks, number of Hispanic Asian & Pacific Islanders to non-Hispanic Asian & Pacific Islanders and number of Hispanic American Indians to non-Hispanic American Indians
- White Hispanic + white non-Hispanic
- Black Hispanic + black non-Hispanic
- Asian & Pacific Islander Hispanic + Asian & Pacific Islander non-Hispanic
- American Indian Hispanic + American Indian non-Hispanic
This information is provided by the Division of Research and Epidemiology within the Department of Public Health.
