A Consistent Lack of Consistency: Definitions, Evidentiary Expectations and Potential Use of Meaningful Change Data in Clinical Outcome Assessments Across Stakeholders. Results from a DIA Working Group Literature Review and Survey.

Background: Clinical outcome assessments (COAs) measure how patients feel or function and can be used to understand which patients experience benefits of treatment and which do not. Interpretation of COA data is influenced by how meaningful change is defined. We aimed to compare how different stakeholders define, assess, and use meaningful change for decisions that impact patients.

Methods: A targeted literature review was undertaken in July 2021 using Medline, Embase, online grey literature search engines, and stakeholder organization websites. Additionally, a stakeholder survey on meaningful change was fielded between March and June 2023. Both quantitative and qualitative methods were used to analyze responses and identify key themes.

Results: The literature review resulted in 86 references. These revealed different approaches to define, measure and validate meaningful change. There were 248 survey responses. Many respondents felt the terminology and methods for defining meaningful change are confusing. Respondents also emphasized the importance of distinguishing within-patient and between-group change, and defining meaningfulness from the patient perspective (most patients and caregivers do not share a similar definition of meaningfulness as their healthcare professionals).

Conclusion: Four key recommendations for defining, establishing, and interpreting meaningful change estimates for COAs are: (1) Be clear on the type of "meaningful change" that is discussed or needed for a COA, (2) Ensure the "patient voice" is informing meaningful change estimates/definitions, (3) Acknowledge that a meaningful change estimate for a COA may differ between populations, diseases, and disease states, and (4) Disseminate data in a way that reduces ambiguity.