cmorrison – The Final – Blogpost Edition



The United States spends more on healthcare than any other country. Unfortunately, the United States does not experience benefits that correlate with this increased spending. Currently the US is facing sky rocketing costs of care but an overwhelming lack of coverage, particularly those with decreased income. The solution to this problem is to understand the utilization of healthcare services within the US and develop interventions to alter this pattern. This project focuses on the healthcare utilization in California, and provides a suggestion for an intervention regarding preventive care in Los Angeles County. All health related data for this project came from AskCHIS the online resource for California Health Interview Survey.



Most of the expensive use of healthcare services in California is the result of treating advanced complications (and sometimes not advanced complications) with expensive technology. Most of these visits are downstream events that could have been resolved if care had been sought at the onset of the first symptoms. However, this delay of care is often thought to be associated with income. Here is what California looks like from a county level:

What we would hope to see in the above graph is a clear trend between median income and delay of care. This would mean that the counties who represent the lowest third in terms of median income (white) would have the highest percentage of persons who delayed care (red cross-hatch). Instead, we see no clear trend. This could be for a whole host of reasons: residual confounding due to aggregation of data at the county level, the percentage of population that needed to seek care in that county, or there actually could be no general trend between income and care seeking behavior. Perhaps, if we look at the distribution of hospitals in California it will provide some insight…

What this map demonstrates is that hospitals in California are typically located where people are located. The red line shows the geographic distribution of hospitals (one standard deviation). Though the distribution doesn’t help with our investigation, it certainly is soothing to know that hospitals are distributed in proportion to number of people, and not due to income. But there are other forms of care besides hospitals, and perhaps the most important form of care is preventive medicine or primary care. However, the US does suffer from a lack of Primary Care Physicians, and California has a severe shortage. Let’s look to see if this shortage is related to the distribution of hospitals:

Here we see the health care professional shortage areas for primary care physicians (HPSA-PCP) in bright green. We can see that it is not very well correlated with hospital distribution, but is slightly correlated with lower median income (the green tends to cover grey and white areas). That makes sense, but there is more to the story. Given the lack of detail at the county level, let’s focus on Los Angeles county to figure out what is going on, and what we can do about it.



The first thing to do is to look at the distribution of hospitals within LA county and median income by census tract.

What is interesting about this map is that the geographic distribution of hospitals in LA County (the red circle) almost directly corresponds with the lowest quartile of median income. This means that people who have the least amount of money, have the easiest geographic access to hospitals. Could this account for overuse of emergency rooms?

Let’s see who is using emergency rooms in LA County…

Well. It seems those with the least amount of money ARE the ones using these hospitals. But is that because they live in a Primary Care Physician Shortage Area (HPSA-PCP)?

For Central LA County it is true: Those that live in the center of the hospital distribution (red circle) and live in the center of HPSA – PCP (blue circle) are the ones with the lowest income (white census tract area). Due to this correlation, this is the area that will be the target for a proposed intervention.


The proposed intervention aims to increase use of prevention medicine by those in low income areas. First we will identify the hospitals located in HPSA-PCP areas. We will target those hospitals to either provide directly, or provide direct linkage / access to primary care physicians. They can either develop a section of their hospital, or for places where that is not feasible, they can coordinate with physicians nearby, and contribute financially to the development of primary care centers. Next we will identify schools within the vicinity (5 miles) of these hospitals and provide the information on how to access these new resources, along with education on the importance of primary care.

Let’s begin with identifying the hospitals within the HPSA – PCP areas in LA County, and determining what school districts they are in:

It seems that all of the Hospitals located within HPSA – PCP Areas reside in two school districts: LAUSD and Long Beach School districsts (see references below, when I embed the link for LAUSD it cuts off whatever I have written beyond it).


–Low income areas are surrounded by hospitals, but lack primary care resources
–A new initiative needs to be implemented in order to increase access and utilization of preventive services
–Hospitals in HPSA – PCP areas need to incorporate or link to innovative delivery methods of primary care in a Preventive Care (PC) Initiative
–The PC Initiative should facilitate access and information about preventive services in nearby schools
GIS is incredibly useful when addressing health services utilization, and should be further utilized in health services research.
Models were used to create the PC Initiative targets.
and an additional model for Long Beach Schools:
•Healthcare Facilties  Shapefile –
•HPSA PCP Shapefile –
•All Health related information came from the California health Interview survey – Ask CHIS –
•LB School Address Information (original data) –
•LA USD List –,142911&_dad=ptl&_schema=PTL_EP
•Geographic Shapefiles for California and Counties –