Reducing Selection Bias While Maintaining Precision Through an Integrated Analysis: 2-Year Longitudinal Analysis of Imaging Outcomes in the SPondyloArthritis Caught Early Cohort

Poster presenter: Liese de Bruin, MSc, PhD Candidate, Leiden University Medical Center, the Netherlands

Poster title: Reducing Selection Bias While Maintaining Precision Through an Integrated Analysis: 2-Year Longitudinal Analysis of Imaging Outcomes in the SPondyloArthritis Caught Early Cohort

Poster Session C: 10:30 a.m.–12:30 p.m. on Tuesday, October 28

What is your poster about?

“In ongoing cohort studies, imaging outcomes are usually evaluated across multiple reading rounds by several readers. However, often only data from the last reading round are used, in a so-called completers analysis. Using an integrated analysis is a method of incorporating scores from multiple readers and reading rounds, ensuring the use of all available information. We assessed whether an integrated analysis, using available imaging data over time from different reading rounds, affects the precision of change estimates in early axial spondyloarthritis (axSpA), using a completers analysis as reference. In our longitudinal study, the integrated analysis was shown to allow for the inclusion of all available data from all patients, thereby reducing selection bias in determining the population for analysis, while maintaining precision of change estimates in patients with early axSpA.”

Why did you decide to investigate this topic?

“Often, only scores from the most recent reading round are used, disregarding valuable data from previous reading rounds and potentially introducing selection bias by excluding participants lost to follow-up. Using an integrated analysis could be a promising alternative to include most available data into a model for longitudinal analysis.”

What are you working on next related to this research?

“Two related projects I have been working on have also been accepted as posters at ACR Convergence: Longitudinal Analysis on Imaging Outcomes: Should We Use the Individual Scores from Multiple Readers or Rather the Consensus or Average of Readers? (poster #1958) and Which Instrument Measuring Structural Damage Progression in Axial SpA Is Most Sensitive to Change? Analyses from the SPondyloArthritis Caught Early Cohort (poster #0539).

“Furthermore, I am now making use of the integrated analysis, instead of completers analysis only, in projects I am working on.”

What excites you most about your work?

“Related to this project, I enjoy seeing how the method can enhance not only our own research but (possibly) also that of others, which ultimately can contribute to better information to support better clinical care.”

What are you most looking forward to at ACR Convergence 2025 in Chicago?

“I am looking forward to several interesting sessions in rheumatology, presenting my posters, and connecting with colleagues from across the field.”