Facility Market Share and Patient Origin, 2017 and 2022

Facility Market Share and Patient Origin, 2017 and 2022#

The Market Share Area Map by Facility, 2017 and 2022, provides a side-by-side comparison of two healthcare facilities and identifies the market share changes for each facility from 2017 and 2022 by ZIP code. A facility’s market share in a ZIP code area represents the percentage of patients from that specific area who went to that facility for IP, ED, or AS treatment^†. Each ZIP code from which the selected facility received patients is categorized into one of three categories (indicated by color):

1. Lost Market Share (orange) if the facility had market share in the ZIP code area in 2017 which dropped to 0 in 2022,
2. Maintained Market Share (grey) if the facility had market share in the ZIP code area in both years, and
3. Gained Market Share (blue) if the facility went from having no market share in the area in 2017 to having some market share in 2022.

Hovering over a ZIP code area within either map will display the market shares of up to five facilities in that specific area for the years 2017 and 2022. All facilities below a 10 percent threshold are combined to form an ‘Other Facilities’ group, possibly including the facility of interest.

The Market Share Area Map by ZIP Code, 2022 identifies where patients from a specified ZIP code went to for IP, ED, or AS treatment^† (darker colors represent higher volume of encounters). In addition, the top five Major Diagnostic Categories (MDCs) are provided for the same ZIP code. Each MDC corresponds to a major organ system (e.g., Respiratory System, Circulatory System, Digestive System) rather than a specific disease (e.g., cancer, sepsis). The MDCs are generated using only the IP hospital records but are shown regardless of which “Patient Type” is selected. Hovering over a facility within the map will display the number of patients of the selected type who went to that facility from the selected ZIP code for the years 2017 and 2022.

Note^†: Physician-owned AS clinics do not report their data to HCAI and, therefore, are not included here.

How HCAI Created This Product#

These visualizations were built using HCAI’s Patient Discharge Data, Emergency Department Data, and Ambulatory Surgery Data for 2017 and 2022. Only facilities that were open in both 2017 and 2022 were included. HCAI also provides market share comparisons between 2013 and 2018, as well as 2015 and 2020.

To protect patient personal information, the California Health and Human Services Agency has adopted a policy of statistically masking or de-identifying sensitive data (CalHHS Data De-identification guidelines). Based on these guidelines, ZIP codes providing 10 percent or fewer of the patients for the selected facility and patient type were removed from the first visualization and the accompanying dataset. Patients counts of 11 or fewer (but greater than 0) were suppressed in the second visualization and the accompanying dataset.