Third-Party Administrator (TPA) ESIS recently switched bill review vendors, which unfortunately delayed the delivery of thousands of electronic Explanations of Review (e-EORs).

e-EORs are critical to e-billing, automatically posting payment information to the provider’s electronic billing (e-billing) system and confirming the payment's timeliness. Accordingly, California law and regulations require payers to send providers e-EORs in response to all e-bills.

Notably, ESIS’s vendors worked admirably to address the problem. daisyBill initially contacted CompIQ, ESIS’s previous bill review vendor, which immediately put our team in touch with StrataCare, ESIS’s current bill review vendor. These vendors, along with ESIS’s clearinghouse, Data Dimensions (reportedly soon to be acquired by OneCall), made remarkable progress in solving the non-compliance and retroactively delivered the bulk of the missing e-EORs.

However, the underlying e-EOR problem remains for ESIS.

daisyBill will continue to monitor the situation closely. As of this writing, ESIS has failed to deliver e-EORs for roughly 8% of e-bills providers submitted from January 2025 through March 2026. Given the diligence CompIQ and StrataCare have demonstrated so far, we are hopeful that ESIS will reach 100% e-EOR compliance soon.

ESIS e-EOR Non-Compliance Rate Spikes

In January 2026, our daisyData revealed a troubling trend: the rate at which ESIS failed to send e-EORs had crept up throughout the second half of 2025 before spiking in the final two months of the year:

1. Through the first half of 2025, ESIS's missing e-EOR rate hovered between 2% and 3%.
2. Starting in July, the rate began climbing, hitting 20% in July and 29% in August.
3. By November, nearly half of all e-bills submitted to ESIS were missing e-EORs.
4. By December, the ESIS e-EOR non-compliance rate had reached an abysmal 74%.

As of January 21, 2026, over 11,000 ESIS e-EORs were missing, giving ESIS a 20% overall non-compliance rate for 2025.

On January 22, 2026, daisyBill reported the spike to CompIQ, ESIS's bill review platform. CompIQ revealed that ESIS was in the middle of a major migration from CompIQ to StrataCare.

According to CompIQ, ESIS’s rapid uptick in e-EOR failures in November and December 2025 tracked with the increased volume of bills moving to StrataCare. Admirably, CompIQ did not hesitate to help tackle the problem, despite winding down its partnership with ESIS. CompIQ gave daisyBill a direct contact at Stratacare, a critical introduction.

CompIQ, StrataCare, and Data Dimensions Make Progress

On January 23, 2026, daisyBill contacted StrataCare and copied ESIS, reporting the e-EOR failures and requesting a timeline for ESIS's compliance. StrataCare responded the same day, confirming it was investigating.

Over the next two months, StrataCare, CompIQ, and Data Dimensions actively collaborated to address the problem. The coordinated effort paid off; by April 10, 2026, the data reflected a remarkable turnaround. For November 2025, the percentage of missing e-EORs had fallen from 48% to 6%. For December 2025 e-bills, the rate dropped from 74% to 2%.

While the proactive efforts to remediate these failures are laudable and welcome, ultimately, nothing less than 100% compliance with state law and regulations is acceptable. That acknowledged, CompIQ and StrataCare’s efforts so far give us confidence that full compliance is attainable for ESIS.

Responsible Vendors: A Payer’s Best Friend

The California Division of Workers’ Compensation (CA DWC)’s Electronic Medical Billing and Payment Companion Guide is clear: no matter what vendors are involved, the payer is legally “responsible for the acts or omissions” of its vendors.

In this case, the e-EOR failure is ESIS’s sole responsibility. Fortunately, its vendors are clearly working hard to resolve it. Most admirably, CompIQ connected daisyBill with StrataCare and worked closely with both, rather than washing its hands of a soon-to-be-former client’s crisis.

daisyBill will continue pressing ESIS and its vendors for the missing e-EORs, the lack of which has imposed real administrative friction on practices. While ESIS still has a legal obligation to reach 100% compliance, the team effort to turn this situation around is a mark of real professionalism for the TPA’s vendors.

The correspondence timeline below outlines the efforts of daisyBill and the vendors to get ESIS on track.

Correspondence Timeline

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