# Presentation: 918839

## Using The American Community Survey and GIS in Breast Cancer Screening

- Jane L. McCall Garb
- Amy K. Pasini
- Jessica R. Schueler
- Isha A. Mustafa
- Richard B. Wait

- Baystate Medical Center GIS Program
*Springfield, Massachusetts*

- Sponsored by the US Census Bureau

## Who are we?

- culture, commerce and government
- in Western Massachusetts.

**Springfield, Massachusetts**

- Springfield is a medium-sized
- city located at the crossroads
- of New England

***Springfield***

-  Serves a metropolitan
- area of more than 500,000 residents

*Who are we?*

**Notes:**
Springfield is a mid-sized city of approximately 150,000.
The surrounding metropolitan area is comprised of more than 500,000 residents.
Springfield is the major urban center located in Western Massachusetts.
Demographic and socioeconomic diversity make Springfield an ideal climate for investigating the uses of census data. 

## How ACS data can be used to help address health problems with GIS?

***How ACS data can be used to help address health problems with GIS?***

**Notes:**
Our project demonstrates how data from the American Community Survey (ACS) can be used to help address healthcare problems, using a geographic information system. 
This presentation will focus on our approach and methodology rather than on specific results or conclusions.

## What is the American Community Survey (ACS)?

- survey by the US Census
- uses questions from the Census long-form
- data collected monthly and reported annually on a sample of the population

**Notes:**
The American Community Survey is a new program underway at the Census Bureau.  If funded by Congress, it will begin producing annual data in 2004, and will replace the long form in the 2010 census.

Even small areas will benefit from the American Community Survey; data for the smallest areas, census tracts, will be aggregated for 5 years and produced as an annually refreshed 5-year average.

The program has been tested over the last several years in a number of sites and under a variety of circumstance to ensure the successful feasibility of conducting a nation-wide operation beginning in 2003.  At that time, the annual sample will be 3 million households.

The content of the American Community Survey is the same as the census long form, and has a few extra questions.

## ACS Comparison Sites

- American Community Survey
- (1999 - 2002)
- 31 Comparison Sites

**Notes:**
Currently there are 31 pilot sites for the American Community Survey, which have been chosen to demonstrate the utility of yearly data collection. 
Hampden County, MA where Springfield is located is one of these sites.
The Citywide partnership in Springfield, MA, with Baystate Medical Center as the identified contractor, was chosen to undertake two demonstration projects:  advanced Breast Cancer and Youth Violence.

## Advantages of ACS 

- most current/accurate estimates
- yearly updates allow tracking of  time trends
- additional questions not included in Census

**Notes:**
The American Community Survey has several advantages over the once-every-ten years or decennial census:
--Provides most current available data on population estimates
--Yearly updates allow tracking population shifts over time
--Additional questions not included in Census

## Limitations of Current ACS Data

- estimates from a sample
- estimates based on weights from 1990 Census
- 2002 profiles will be more accurate

**Notes:**
Limitations on current use of American Community Survey data include: 
--Produces estimates from a sample of population -  not exact counts
--Estimates are weighted to give greater representation to areas of greater population size
--Current weights based on 1990 census population proportions; beginning in 2002, estimates revised with 2000 census weights, resulting in more accurate estimates

Current American Community Survey estimates should be used as community profiles with emphasis on relative proportions in each population subgroup rather than as exact numbers of people.  

An example, in using estimates of ethnicity, focuses more on determining what is the predominant ethnic subgroup in a geographic area rather than on a count of how many people there are from each subgroup.

Standard errors for the American Community Survey are conservative -- actual variances are smaller than the American Community Survey estimates. This makes ACS confidence intervals wider than the actual confidence intervals. The result is that the true range of values is actually less than given by the American Community Survey estimates, to be safe. 

## Defining the Problem

**Notes:**
In choosing a demonstration project we first had to define a relevant problem to be studied in our community. 
We employed visualization to do this.

## Slide 9

**Notes:**
We used the Atlas of Cancer Mortality to identify a type of cancer that had high mortality rates over the last 25 years in Massachusetts, representing a particular problem in our state. Such was the case with breast cancer in women.  (The darker the red = the higher the mortality rate.)
We then looked at the magnitude of breast cancer mortality in our own county, Hampden County.  While it was not the highest in the state, still the mortality rate of approximately 30 per 100,000 population was of significant concern.
To address the problem of breast cancer mortality, it seemed logical to focus on advanced stage disease.  Previous research has clearly established that by lowering the rate of advanced disease with increased mammography screening,  breast cancer mortality can be reduced. 

## Breast Cancer Rates by County in Massachusetts

- * *Rate per 100,000 women*
*  **Age-adjusted for the 1970 US population*
*   **Source: Atlas of Cancer Mortality*

**Notes:**
We had data on advanced stage disease from the Massachusetts Department  of Public Health. This showed that the proportion of breast cancer cases with advanced disease was higher in Springfield than the rest of the state. 

## Magnitude of Advanced Stage Breast Cancer

*Source: Massachusetts Department of Public Health*

**Notes:**
From this we concluded that advanced stage breast cancer in Springfield was a significant public health problem and worthy of study.  Any findings from this study could be used  to better plan an approach to breast cancer screening intervention.

## Create a profile of communities in Springfield in need of increased breast cancer screening to aid in planning intervention programs

*Purpose*

**Notes:**
Our purpose was to create a profile of communities in Springfield, Massachusetts in need of increased breast cancer screening to aid in planning intervention programs.

## Specific Aims

- identify geographic areas with high rates of advanced disease
- identify socioeconomic and demographic factors in advanced disease

**Notes:**
Specifically we wanted to:
--Identify parts of the city with high rates of advanced disease
--Identify socioeconomic and demographic factors in advanced disease

Knowledge of these factors could then be used to plan intervention programs.

## Data Sources

*Data Sources*

**Notes:**
For this purpose, we forged a citywide collaboration to utilize medical data from the major area hospitals, geographic data from the City of Springfield Planning Department and community characteristics data from the American Community Survey to solve the problem.

## ACS Data 

***Individuals***
- Age
- Race
- Ethnicity
- Income
- Education

***Housing ***
- Value
- Tenancy
- Occupancy

***Families/Households***
- Income
- Assistance
- Composition

**Notes:**
We obtained 1999 estimates from the American Community Survey on various population and housing characteristics. Population estimates were available both for the total population and for women over 40. We used the latter in our study. 

## ACS Sampling Methods

*ACS Sampling Methods*

*Data aggregated by police sector*

*9 police sectors*

*2-4% of population sampled in each sector*

**Notes:**
For this study, American Community Survey data were aggregated at the police sector level, as defined by Springfield Planning Office.  This was the smallest geographic unit giving  reasonably precise estimates. 
There are 9 police sectors in Springfield, Massachusetts.
American Community Survey Sampling rates for the sectors ranged between 2 and 4% of the total population. 

## Hospital and Municipal Data 

- address
- date of diagnosis
- stage at diagnosis
- race
- age
- marital status

***Patient Data***

**Notes:**
We obtained patient clinical and demographic data on all cases of breast cancer from 1995-1999. The Oncology registries of Baystate Medical Center and Mercy Medical Center capture approximately 95% of the reported cases of breast cancer in the city.
We defined cases of advanced disease to be American Joint Cancer Committee (AJCC) Stage 2 or greater. 
The City of Springfield Planning Department keeps accurate, up-to-date geographic data in the form of ArcView shape files which we used for sector boundaries and for geocoding case locations and mammography facilities. 

## Our Approach

**Notes:**
Our approach, as noted, was visualization.  We wanted to see the geographic distribution of cases of advanced disease to determine where they were concentrated. 

## Locating Areas of Concentration

*Locating Areas of Concentration*

**Notes:**
This dot density map was tested for significant geographic clustering use the spatial scan statistic.  This tells us where raw  numbers of cases were greatest and more resources were needed, for example, where mobile mammogram units and educational or other intervention programs would be likely to have the highest yield.
Our current data show no visually or statistically apparent spatial clustering of cases. On this basis, a more global approach to intervention seems warranted. 
We were also interested in whether the location of mammogram facilities influenced the rate of advanced disease in the different police sectors.

## Risk of Advanced disease:1995-1999 Prevalence per 1000 Women > 40

*Risk of Advanced disease:**1995-1999 Prevalence per 1000 Women > 40*

***Sector H = 7.7***

**Notes:**
To account for the size of the underlying population of women greater than 40 and estimate the risk of getting advanced disease, we used American Community Survey estimates as the denominator to calculate the prevalence rate of advanced disease per thousand women greater than 40 over the five year period.
We mapped these rates using choropleth maps to look for sectors with unusually high rates. 
Sector H has the highest rate of late stage disease. We needed to investigate what characteristics of this sector make women at higher risk for advanced disease.

## tests for factors in rate of advanced disease
police sector is unit of analysis
ACS estimates are independent variables
rate of advanced disease per women older than age 40 is dependent variable
accounts for spatial proximity

- police sector is unit of analysis
- ACS estimates are independent variables
- rate of advanced disease per women older than age 40 is dependent variable
- accounts for spatial proximity

*Spatial Regression: **Factors in Advanced Disease*

**Notes:**
We used spatial regression to test for significant socioeconomic and demographic factors in advanced disease. 
Using regression we hoped to sort out effect of various factors which may not be apparent by mapping and Identify characteristics of high-risk population subgroups. The unit of analysis was the police sector. 
American Community Survey estimates for sector population and housing characteristics were the independent variables in the spatial regression.
The outcome variable was the rate of advanced disease per thousand women over 40.
Spatial regression accounts for effect of spatial proximity of the police sectors. 
The rates used in this study reflect etiologic factors for overall risk of breast cancer as well as risk of advanced disease. Since the purpose of our study was targeting high-risk areas and population subgroups, we did not need to separate out the causes of advanced disease from those of breast cancer.

## Results of Spatial Regression

**Notes:**
This slide shows the results of spatial regression. 
There were four significant factors: black race, presence of a high school diploma, and foreign born or married status in women over 40.  
These factors were all positively related to the rate of advanced disease. 

Rates of advanced disease were higher in sectors with high rates of black, married or immigrant women over 40, or those with a high school diploma. 

The number of mammogram facilities in a sector did not affect the rate of advanced disease in that sector

This information can help us in designing intervention programs. 

## Targeting High-risk Populations

*Targeting High-risk Populations*

***High Rate of ***
***Black Women***

***High Rate of Married ***
***&  High School Graduate***
***Women***

**Notes:**
Since black race and foreign born status are significant risk factors in advanced disease, areas of the city with high concentrations of these populations should be targeted for intervention programs.

## Designing Intervention Programs

- account for educational level of those at risk
- work with organizations for foreign-born
- work with African-American organizations

**Notes:**
We can also use these results to design intervention programs.

The fact that the rates of advanced disease were higher in areas with a greater proportion of women who were high school graduates indicates that educational materials should be at a higher educational level so as not to discourage educated women from participating.

The importance of foreign birth suggests potential avenues for reaching high-risk women through various national and cultural organizatioins such as the Greek Cultural Council of Springfield.

The increased risk for black or African American women suggests working with African American organizations, many of which already target specific health problems.

## Summary: How we can use ACS Data in Healthcare

- demographic profile of communities
- calculation of risks (incidence/prevalence)
- planning/resource allocation
- identification of risk factors in disease
- design of intervention programs

**Notes:**
Summary:
The American Community Survey data, provided on an annual basis, allows us to create a demographic profile of communities or sub-areas within the community 
Provides denominators for calculation of risks (incidence or prevalence rates)
Aids in planning and resource allocation by identifying size and location of high-risk populations
Used in analysis for identification of risk factors in disease which can be applied to the design of intervention and prevention programs

## Further Applications

- neighborhood level
- state rates
- individual level

**Notes:**
With more data from 2000 and 2001(aggregated at neighborhood level) more meaningful geographic areas for community intervention and update rates with data from Massachusetts State Cancer Registry, we plan to examine our individual patient data to determine specifically what patient factors are involved in delaying diagnosis over and above the risk of getting the disease, by examining rates of advanced disease out of all breast cancer patients.

To do this we will use American Community Survey data to augment missing or incomplete socioeconomic characteristics of individual patients by including characteristics of a woman’s area of residence in the analysis along with her individual-level characteristic. 

We will also examine the distance of a women’s residence from the nearest mammographic facility as a factor in advanced disease.