Cover: Informing the Development of Standardized Clinical Definitions of Neonatal Abstinence Syndrome and Neonatal Opioid Withdrawal Syndrome

Informing the Development of Standardized Clinical Definitions of Neonatal Abstinence Syndrome and Neonatal Opioid Withdrawal Syndrome

Results of Two Modified-Delphi Expert Panels

Published May 3, 2021

by Laura J. Faherty, Stephanie Dellva, Emily Dao, Dmitry Khodyakov

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Research Questions

  1. What are the key components of standardized clinical definitions of NAS and NOWS?
  2. What are experts' proposed definitions of these terms?

From 2010 to 2017, the United States experienced a significant increase in maternal opioid-related diagnoses and neonatal abstinence syndrome (NAS). NAS is increasingly being referred to as neonatal opioid withdrawal syndrome (NOWS), as opioids are becoming the most common cause of neonatal withdrawal, whether alone or in the presence of other substances. A major challenge in the field is the lack of a standardized clinical definition of NAS.

To address this challenge, the authors convened two modified-Delphi expert panels consisting of national experts on substance-exposed mother-infant dyads. Through these online panels, the authors solicited expert opinion to inform the development of clinical definitions of NAS and NOWS for use at the bedside as part of the U.S. Department of Health and Human Services initiative on NAS. To convene the panels, the authors used ExpertLensTM, a previously evaluated platform for conducting iterative online modified-Delphi panels. Participants provided initial responses to study questions about key components of the clinical definition of NAS and NOWS; reviewed how their responses compared to those of other participants; and revised their responses based on group feedback and discussion, if needed.

Eighteen experts provided numeric ratings and free-text comments to contextualize their responses. Simple descriptive statistics, including frequency distributions, medians, interquartile ranges, as well as the RAND/UCLA Appropriateness Method Manual's approach to determining consensus in expert panels were used to analyze rating data, and the authors thematically analyzed the experts' free-text comments.

Key Findings

  • Experts agreed that the information about presence of clinical signs of withdrawal in the context of in utero substance exposure (whether known or "reasonably suspected") is necessary for a definition of NAS or NOWS.
  • The experts identified five clinical signs that are most characteristic of NAS and NOWS but emphasized that the combination of signs of withdrawal, which can present differently in each infant, is most important for making these diagnoses, not any particular sign in isolation.
  • Experts agreed that maternal and infant toxicology test results may be helpful for understanding an infant's clinical presentation but that test results are not required for the diagnosis of NAS or NOWS.
  • The experts generally agreed that the terms NAS and NOWS are used inconsistently and often interchangeably when in utero opioid exposure is present. Many viewed NOWS as a subcategory of NAS and typically use this term when the dominant exposure is opioids.
  • There is a pressing need for the field to continue efforts to standardize terminology around substance-exposed mother-infant dyads, develop precise clinical definitions that inform both short- and long-term support of the dyad, and provide clear guidance in future work on the implementation of these definitions.

Research conducted by

This study was funded by the Office of the Assistant Secretary of Health within the U.S. Department of Health and Human Services (HHS) and conducted by RAND Health Care.

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