Overview of Data Sources

Population

Census data and county estimates from the U.S. Census Bureau were used to calculate the size of the population at the county-level for each of the Border States.  Population figures used for calculating the health provider-to-population ratios in this report are based on updated data from the U.S. Census Bureau, Population Division, Population Estimates Program (Release Date:  August 11, 2005).

Prevalence Data

Data for 2002 from the Behavioral Risk Factor Surveillance System (BRFSS) were used to estimate the proportion of the population:  without health coverage; ever diagnosed with diabetes; who are overweight or obese; who have had a dental visit within the past year; and, who currently have asthma.   In addition, the proportions of females who had a pap smear or mammogram were also estimated.

The BRFSS is a survey that collects information about adults (18 and older and living in households); persons younger than 18 are not represented by the survey results provided in this report.

While the sample allows estimates to be produced for areas, such as the Border regions in each of the Border States, most counties do not have large enough samples to produce reliable estimates for individual counties.

State Licensure Data

Agencies in each State that handle data for licensed health professionals were contacted to obtain data for the current report.  Among these were State boards for physicians, dentists, registered nurses, physician assistants, psychologists, and social workers.  Psychiatrists and three categories of specialty nurses were identified when specialty information or another designator was included in the data sets.

Delays in obtaining data resulted in inconsistencies in the reporting date of the data as most licensing boards process and compile data requests on an as needed basis and this Study may have had a lower priority rating at one board than at others.  Reporting dates were included in the respective tables in the report.

The health professions data used in this report, in most cases, were purchased from the respective Board in each State.  Licensure Boards most often receive requests for mailing lists.  Consequently, for some boards, a mailing list was purchased only when no other data were available for analysis.  Some boards were able to include additional variables to mailing lists.

State Health Data

Vital statistics, hospital discharge, and incidence data for selected diseases were also requested from State health departments to present the health status of the regions as well as State totals.  Healthy Border 2010 Objectives guided the selection of health indicators used in this report.

Description of Geocoding Process

State Licensure Data

Data received from State licensure boards or State organizations were “geocoded” using Geographic Information Systems (GIS) software in an effort to determine the location of the health professional.  This permitted assignment of health professionals to a county based on the county federal information processing standards (FIPS) code assigned by the GIS software.  The following process describes the method by which an address was “geocoded.”  The address used was determined by staff (in consultation with the suppliers of the data when possible) to best represent the practice location of the health professional.  Using batch processing, on the first pass, addresses were matched only on the exact street name, house number and zip code.  On the second pass,^[109] addresses were matched by “relaxing” the zip code; this allowed a match for address in a different zip code.  On the third pass, street name and house number for the address were relaxed to allow matches for parameters similar to address components (such as misspellings to be matched to the address).  On the final geocoding pass (usually by this stage only a small percentage of records were not matched), records were matched by zip code only.  Once these passes were complete, remaining unmatched records were viewed through interactive mode in GIS to determine if a match could be made by searching for visible errors in the address field.  Once geocoding was completed, data were moved into Statistical Package for the Social Sciences (SPSS) software.  The remaining unmatched records were assigned a county in SPSS based on the city name.  For example, since PO Box addresses could not be geocoded, they were assigned a county FIPS code based on the name of the city.

State Health Data

Health related information such as vital statistics, hospital discharge, and incidence data, were usually assigned a county code by the State agency/office responsible for the data.  Data reported here reflect place of residence of each case, not the place of occurrence.

Data from Licensing Boards in California

Data licensing boards did not have the demographic and specialty data needed for analysis.  Licensing boards were not allowed to collect demographic data; the collection of specialty data for physicians had begun, but this information would not be available in time for the Border Profiles Reports.

Proportion of Missing Data for Physicians, Dentists, and Registered Nurses in California

Variable	Physicians	Dentists	Registered Nurses
Race/Ethnicity	NA	NA	NA
Age	NA	NA	NA
Gender	NA	NA	NA
Patient Care	NA	NA	NA
Specialty	NA	NA	A
Hours/Week or Part-/Full-Time	NA	NA	NA

NA= Not available
A= Available

The “Masterfile” from the California Department of Consumer Affairs (DCA) was purchased because it included comparable information within the State of California for every profession in this Report.  All data runs in this report for health professionals were compiled from data received from the DCA and reflects a date of July 1, 2004.  Problems with the data set include:

• Practice address not available, only address
• Specialty information not available for physicians and dentists; the lack of specialty data for physicians impeded the ability to calculate current psychiatrist to population ratios for the State of California, as well as ratios for primary care physicians
• For physicians, field not available to indicate direct patient care
• For dentists, field not available to indicate private practice
• For all professions, information was not available on the following items:  race/ethnicity; Age or date of birth; Gender; Hours worked per week of part-/full-time employment status; Field to identify health professional as providing patient care

The inability to obtain codes to determine which health professionals provide direct services to the population using data from the DCA hindered analysis.  Thus, this Report includes all professionals with an active license and does not reflect the number of health professionals providing direct patient care in their respective health fields.

An additional problem with health professions data for California was the availability of only one address which was geocoded to determine the location of the health professional’s reported place of practice.  The problem with this assumption was the inability to determine whether the address in the data set reflected the health professional’s home or business/practice address.

Data from Health Offices in California

Vital Statistics

Vital statistics data for 2002 were received from the Office of Health Information and Research, California Department of Health Services.^[110]

Hospital Discharges

Hospital discharge data for 2002 were received from the Office of Statewide Health Planning and Development, California Health and Human Services Agency.

Incidence Data

Breast and Cervical Cancer

Data for breast and cervical cancer cases diagnosed in 2001 were received from the California Cancer Registry, California Department of Health Services.

HIV/AIDS

Data for HIV/AIDS cases diagnosed in 2002 were received from the Office of AIDS, California Department of Health Services.^[111]

Hepatitis A and B

Number of hepatitis A and B cases diagnosed in 2002 and 2003 were received from the Infectious Diseases Branch, Division of Communicable Disease Control, California Department of Health Services.

Tuberculosis

Number of tuberculosis (TB) cases diagnosed in 2002 were provided by the Tuberculosis Control Branch, Division of Communicable Disease Control, California Department of Health Services.

Immunizations

Information about childhood immunization status for 2003 was obtained from the Centers for Disease Control and Prevention, National Immunization Program (NIP).  The National Immunization Survey (NIS) provides immunization status for States, but not counties.  Results were also not available for all race/ethnic groups.  For California, State level results were available for Non-Hispanic Whites and Hispanics/Latinos(as) only.