Oxnard - Systemic Inequities in Ambulance Service

The new ALS Unit, Squad 68, is stationed in the south side of Oxnard which routinely experiences the highest number and concentration of delayed response times.

Using data from the local dispatch system, the Oxnard GIS team was able to map the location and density of ambulance responses that did not meet performance standards from 2017 through 2021.

The performance standards were calculated using the time from assignment to time arriving on scene from the incident data.

Priority dispatch code calls that arrived after 8 minutes, and non-priority code calls that arrived after 15 minutes were identified as not meeting the response standards.

By adding U.S Department of Housing and Urban Development (HUD) Low and Moderate Income (LMI) data, the GIS team was able to analyze the relationship between low income areas and the density of underperforming ambulance responses.

The data revealed that areas with more than 50% of residents considered low to moderate income (LMI>50%) had the highest density of underperforming ambulance responses.

Areas with LMI >50% had nearly twice as many underperforming ambulance responses (4,373) compared to more affluent areas of LMI<50% (2,270).

Properly used, system status management would adapt to these high density areas to make more resources available.

Unfortunately, the higher density of underperforming ambulance responses followed a very similar trend year after year from 2017 through 2021.

In 2017 the number of underperforming calls were as follows:

• LMI < 50%
• 458 delayed responses
• 46.07 delayed responses per sq mile

• LMI > 50%
• 903 delayed responses
• 52.62 delayed responses per sq mile

• LMI < 50%
• 446 delayed responses
• 44.86 delayed responses per sq mile

• LMI > 50%
• 841 delayed responses
• 49.01 delayed responses per sq mile

• LMI < 50%
• 366 delayed responses
• 36.81 delayed responses per sq mile

• LMI > 50%
• 711 delayed responses
• 41.43 delayed responses per sq mile

• LMI < 50%
• 482 delayed responses
• 48.48 delayed responses per sq mile

• LMI > 50%
• 996 delayed responses
• 58.04 delayed responses per sq mile

• LMI < 50%
• 518 delayed responses
• 52.1 delayed responses per sq mile

• LMI > 50%
• 922 delayed responses
• 53.73 delayed responses per sq mile

Current private ambulance company agreements with the local EMS agency only utilize one performance measure to ensure contractual compliance.

EOAs 1-7 are treated as one single large EOA, ambulance units are permitted to move freely between EOAs.

This results in a manipulation of SSM. Rather than utilizing predictive analysis to enhance SSMs ability to place units where the calls occur, the private ambulance company shifts units to meet its contract target percentage across all EOAs.

Oxnard EOA 6, having the highest volume and call density, loses resources to respond to adjacent areas.

When an ambulance unit leaves its designated EOA, a nearby unit from an adjacent EOA is supposed to "move up" and "bump cover" for the missing unit.

Unfortunately in Oxnard this is not the case. Current private ambulance coverage practice is to "draw down" resources and only backfill when coverage levels become dangerously low.

The 9 identified ambulance units from EOA6 spent a combined 763 days (12% of total time) operating outside of EOA6 from 2017 through 2020.

In return, the 40 ambulance units from the surrounding EOAs spent a total of 362 days inside EOA6.

This represents only a 47.4% reciprocation of service. Less than half of what would be expected.

The private ambulance company has allocated a specific number of unit hours per EOA as part of their contractual agreement with the local EMS agency.

The unit AVL data reveals a different picture.

EOA6 consistently had the lowest percentage of actual unit hours vs the planned unit hours.

Even under scrutiny and with additional pressure by Oxnard, EOA6 was the only area not reaching 100% of planned unit hours.

EOA5, which covers the affluent City of Camarillo, received the highest percentage of of unit hours in the latest available data.

MDC Calibration Issues

Analysis of response data from 2017 through 2021 indicated that 297 incidents reported "on scene" times before the "assignment time"

This could potentially indicate clock calibration issues on the MDCs, which would potentially impact all performance stats.

This phenomenon was verified by the regional dispatch center and is attributable to modem clock desynchronization.

Cancelled Calls

The local EMS agency plan allows for a number exemptions on calls. Cancelled calls are all treated as compliant. These cancelled calls have a significant impact on overall compliance.

Even with allowing exemptions, the ambulance providers did not meet response standards in 3 out of 4 observed years.

Improvement is response delays was directly correlated to planned hour fulfillment as exemplified in 2019 response standard improvements.