---
title: "Psychiatry Expert Witness’ Opinions Regarding the Clinical Sufficiency of Certain Guidelines Admitted"
meta:
  "og:description": "Psychiatry expert witness did cite to the record—specifically the language of the applicable guidelines she opines on"
  "og:title": "Psychiatry Expert Witness’ Opinions Regarding the Clinical Sufficiency of Certain Guidelines Admitted"
  author: "Expert Witness Profiler"
  description: "Psychiatry expert witness did cite to the record—specifically the language of the applicable guidelines she opines on"
---

# Psychiatry Expert Witness’ Opinions Regarding the Clinical Sufficiency of Certain Guidelines Admitted

Posted on February 13, 2025 by Expert Witness Profiler

Kirsten W. sought payment of benefits for her son C.W.’s treatment at Open Sky Wilderness Therapy (“Open Sky”) and Telos Residential Treatment Center (“Telos”) from Defendants California Physicians’ Service d/b/a Blue Shield of California (“BSC”). C.W. was admitted to Open Sky and Telos for treatment of his depression, anxiety, drug and alcohol use disorders, poor impulse control, and other self-destructive behaviors.

To evaluate coverage of Residential Treatment Center (“RTC”) level of treatment for children and adolescents, BSC has relied on various different criteria that were in effect during different periods. Of particular relevance, BSC utilized the 2018 MCG 21st Edition Residential Acute Behavioral Health Level of Care Guidelines (“MCG Guidelines”) and Version 20 of The Child and Adolescent Level of Care Utilization System Guidelines (“CALOCUS”).

Defendants denied Kirsten’s claims for coverage, relying on statements such as “there was never a significant risk that you would harm yourself or others,”and “there is no active suicidal ideation with intent or plan, homicidal ideation, or overt psychosis” to support the decision to deny benefits.

Plaintiff additionally claimed that Defendants violated the Mental Health Parity and Addiction Equity Act of 2008 (the “Parity Act” or “MHPAEA”) by applying acute requirements to subacute mental health treatment.

BSC disclosed [Caitlin R. Costello](https://expertwitnessprofiler.com/expert-witness/Caitlin-Costello/1562611) as an expert for the purpose of providing opinions “regarding the clinical sufficiency of certain guidelines that [BSC] consulted when evaluating the medical necessity of the services allegedly provided to [C.W.].”

Given that Defendants relied on Costello in disputing Plaintiff’s purported MHPAEA violations, the Court first considers whether her report and opinions are admissible under [Federal Rule of Evidence 702](https://www.law.cornell.edu/rules/fre/rule_702#:~:text=Rule%20702%20sets%20forth%20the,is%20a%20relatively%20narrow%20inquiry.).

## **Psychiatry Expert Witness**

[Caitlin Costello](https://expertwitnessprofiler.com/expert-witness/Caitlin-Costello/1562611) is an associate clinical professor in the Division of Child and Adolescent Psychiatry, Department of Psychiatry, at the University of California, San Francisco. She also serves as the chief of child forensic psychiatry in the Psychiatry and Law Program at the University of California, San Francisco. Additionally, she is the medical director for child and adolescent ambulatory psychiatry at UCSF-West Bay. Costello is also the Training Director of the Child and Adolescent Psychiatry Training Program at the University of California, San Francisco.

She is licensed to practice medicine in the state of California and is certified by the American Board of Psychiatry and Neurology in General Psychiatry, Child and Adolescent Psychiatry, and Forensic Psychiatry.

[Want to know more about the challenges Caitlin Costello has faced? Get the full details with our Challenge Study report.](https://app.expertwitnessprofiler.com/login?eId=1562611)

## **Discussion by the Court**

In her expert report, Costello takes no position on whether the disputed services were “medically necessary.” Instead, she opined that utilization of the MCG Guidelines was “clinically appropriate for Blue Shield to consider” in its medical necessity evaluation.

Costello further opined that the MCG Guidelines did not focus solely, primarily, or improperly on acute symptomology, and that BSC’s reliance on the guidelines did not show any clinically improper focus on acute symptomology.

First, Plaintiff argued that Costello’s report did not compare analogous guidelines (such as those of skilled nursing facilities with the MCG Guidelines) and was thus unhelpful to the Court’s analysis. Second, Plaintiff argued that Costello’s report was unreliable because it ignored the language of the Plan and the relevant MCG Guidelines.

#### **Costello’s Report did not Compare Analogous Guidelines**

Plaintiff’s parity act claim is entirely based on her reading of the terms of the MCG Guidelines as requiring acute symptoms in contrast with treatment in a skilled nursing facility, which requires there be “no acute hospital care needs.”

Demonstration that the MCG Guidelines did not require “acute” symptoms was sufficient to defeat Plaintiff’s Parity Act argument. The Court held that Costello’s report is directly relevant to this point.

#### **Costello’s Report was Unreliable because it Ignored the Language of the Plan and the Relevant MCG Guidelines**

Plaintiff essentially argued that Costello’s opinion is incorrect as to whether the MCG Guidelines improperly focus on acute symptomology, based on an alleged lack of “citation to any evidence” and in light of a footnote that mentions “acute” symptoms.

First, the Court held that Costello did cite to the record—specifically the language of the applicable guidelines she opines on. Any interpretations of these guidelines, particularly as to whether they employ acute symptomology criteria, fell under her training and experience.

And it was not unreasonable for Costello to not specifically describe every footnote in her report that she did not believe would change her analysis, particularly when Plaintiff did not mention this footnote previously. A threshold showing of reliability did not mean the “expert’s testimony is ‘undisputably correct’ or without uncertainty.”

Plaintiff also argues that discussion of this footnote in Costello’s supplemental declaration attached to Defendants’ Opposition to Plaintiff’s motion for summary judgment amounts to “untimely” expert testimony because the text of the footnote was available upon review of the MCG Guidelines.

The meaning attributed to the footnote falls within “the contested issue of whether Blue Shield improperly applied guidelines that were too restrictive or otherwise inappropriate,” which Defendants disclosed Costello would testify regarding in their expert disclosures.

There was no indication prior to the summary judgment briefing that Plaintiff intended to argue that this single footnote altered the reasonable interpretation of the MCG Guidelines. Plaintiff also chose not to submit an expert report, a rebuttal expert report, or depose Costello.

Therefore, Costello’s declaration was appropriate to rebut Plaintiff’s new argument. Accordingly, the Court finds Costello’s report and opinions sufficiently reliable for the Court to consider regarding the language and meaning of the MCG Guidelines.

## **Held**

The Court denied the Plaintiff’s motion to exclude the opinions of Dr. Caitlin Costello.

## **Key Takeaway**:

A threshold showing of reliability does not mean the “expert’s testimony is ‘undisputably correct’ or without uncertainty.

Costello’s opinion is not incorrect in light of a footnote that mentions “acute” symptoms because it was reasonable for Costello to not specifically describe every footnote in her report that she did not believe would change her analysis, particularly when Plaintiff did not mention this footnote previously. Moreover, Costello does cite to the record—specifically the language of the applicable guidelines she opines on. Any interpretations of these guidelines, particularly as to whether they employ acute symptomology criteria, falls under her training and experience.

## **Case Details:**

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