Stat Med, 2023 · DOI: 10.1002/sim.9716 · Published: June 15, 2023
This paper addresses how to analyze clustered time-to-event data using pseudo-value regression when the size of the clusters is informative. Informative cluster size (ICS) means there's a relationship between the number of participants in a cluster and the outcome being measured. The authors explore different strategies for adjusting for ICS by reweighting, in the context of pseudo-value regression, which is used to model the effect of covariates on the progression of a disease. The paper includes theoretical arguments and simulation experiments to determine the most accurate strategy for adjusting for ICS. The methods are demonstrated using real-world datasets from a periodontal study and a study of spinal cord injury patients undergoing locomotor-training rehabilitation.
Using the correct ICS adjustment strategy in pseudo-value regression leads to more accurate and reliable statistical inferences about covariate effects.
The proposed methods enable researchers to effectively analyze clustered time-to-event data, particularly in situations where cluster size is informative.
The findings have broad implications for medical research and other fields where clustered data and informative cluster size are common, such as dental studies and rehabilitation research.