Modeling Disease Progression in the Presence of an Outcome-Dependent Visiting Process with Application to Cystic Fibrosis Clinical Data
Pub. online: 26 March 2026
Type: Methodology Article
Open Access
Area: Biomedical Research
Accepted
26 January 2026
26 January 2026
Published
26 March 2026
26 March 2026
Abstract
The timing of longitudinal measurements may depend upon outcome or disease severity. In biomedical studies relying on clinical encounter data, patients often have dense, irregular collections of visit data when suffering a worse health condition. In parallel, the longitudinal measurements may be impacted by the period of irregular visiting. Ignoring the impact of the outcome-dependent visiting process when constructing a longitudinal disease progression model can produce biased results. We propose a Bayesian joint model linking a mixed-effects model for the longitudinal marker and Weibull proportional hazards model with a log frailty for the visiting process, adjusting both longitudinal marker and event processes with covariates. We examine different random effect structures and performance characterizing disease trajectory. Motivated by clinical data on cystic fibrosis lung disease, we estimate the longitudinal process for lung function decline. Individuals with lower lung function tend to have more frequent clinical visits than those with higher lung function. Simulation studies suggest that incorporating a time-dependent Gaussian process is more important for model fit than adding the survival model via joint modeling; the random intercepts model exhibits maximum bias, especially when there is an outcome-dependent visiting process.
Supplementary material
Supplementary MaterialESM1.pdf: Extended results on parameter estimates of the joint models with random slopes or intercepts only (Tables S1-S2); performance across models according to fit statistics (Tables Tables S3-S4); simulation study results on model parameter estimates and performance (Tables S5-S6); trace plots and residual diagnostics from the real data application (Figures S1-S2). ESM2: Collection of files that includes the implementation code for the models and a simulated dataset.
References
Disclosure statement
The authors report that there are no competing interests to declare with respect to the research, authorship, and/or publication of this article.
Asar, O., Bolin, D., Diggle, P. and Wallin, J. (2018). Linear Mixed-Effects Models for Non-Gaussian Repeated Measurement Data. Pre-print arXiv:180402592v1. https://doi.org/10.1111/rssc.12405. MR4166856
Celeux, G., Forbes, F., Robert, C. and Titterington, D. (2006). Deviance Information Criteria for Missing Data Models. Bayesian Analysis 1(4) 651–674. https://doi.org/10.1214/06-BA122. MR2282197
Gasparini, A., Abrams, K., Barrett, J., Major, R., Sweeting, M., Brunskill, N. et al. (2020). Mixed-effects models for health care longitudinal data with an informative visiting process: A Monte Carlo simulation study. Stat Neerl 74(1) 5–23. https://doi.org/10.1111/stan.12188. MR4050397
Geisser, S. and Eddy, W. (1979). A Predictive Approach to Model Selection. J Am Stat Assoc 74(365) 153–160. MR0529531
Gelman, A. (2006). Prior distributions for variance parameters in hierarchical models. Bayesian Analysis 1 515–534. https://doi.org/10.1214/06-BA117A. MR2221284
Lipsitz, S., Fitzmaurice, G., Ibrahim, J., Gelber, R. and Lipshultz, S. (2002). Parameter estimation in longitudinal studies with outcome-dependent follow-up. Biometrics 58(3) 621–630. https://doi.org/10.1111/j.0006-341X.2002.00621.x. MR1933535
McCulloch, C., Neuhaus, J. and Olin, R. (2016). Biased and unbiased estimation in longitudinal studies with informative visit processes. Biometrics 72(4) 1315–1324. https://doi.org/10.1111/biom.12501. MR3591616
Neal, R. (2011) MCMC using Hamiltonian Dynamics. CRC Press, Boca Raton. MR2858447
Neuhaus, J., McCulloch, C. and Boylan, R. (2018). Analysis of longitudinal data from outcome-dependent visit processes: Failure of proposed methods in realistic settings and potential improvements. Stat Med 37(29) 4457–4471. https://doi.org/10.1002/sim.7932. MR3879439
Pullenayegum, E. and Lim, L. (2016). Longitudinal data subject to irregular observation: A review of methods with a focus on visit processes, assumptions, and study design. Stat Methods Med Res 25(6) 2992–3014. https://doi.org/10.1177/0962280214536537. MR3572895
Pullenayegum, E., Birken, C., Maguire, J. and Collaboration, T. (2021). Clustered longitudinal data subject to irregular observation. Stat Methods Med Res 30(4) 1081–1100. https://doi.org/10.1177/0962280220986193. MR4259889
Rizopoulos, D. and Ghosh, P. (2011). A Bayesian semiparametric multivariate joint model for multiple longitudinal outcomes and a time-to-event. Stat Med 30(12) 1366–1380. https://doi.org/10.1002/sim.4205. MR2828959
Spiegelhalter, D., Best, N., Carlin, B. and Van der Linde, A. (2002). Bayesian Measures of Model Complexity and Fit (with Discussion). Journal of the Royal Statistical Society, Series B 64(4) 583–616. https://doi.org/10.1111/1467-9868.00353. MR1979380
Su, W. (2020). Flexible Joint Hierarchical Gaussian Process Model for Longitudinal and Recurrent Event Data. University of Cincinnati. MR4533229
Su, W., Wang, X. and Szczesniak, R. (2021). Flexible link functions in a joint hierarchical Gaussian process model. Biometrics 77(2) 754–764. https://doi.org/10.1111/biom.13291. MR4307670
Sun, J. -D., Sun, L. and Zhao, X. (2005). Semiparametric regression analysis of longitudinal data with informative observation times. J Am Stat Assoc 100(471) 882–889. https://doi.org/10.1198/016214505000000060. MR2201016
Szczesniak, R., Su, W., Brokamp, C., Keogh, R., Pestian, J., Seid, M. et al. (2020). Dynamic predictive probabilities to monitor rapid cystic fibrosis disease progression. Stat Med 39(6) 740–756. https://doi.org/10.1002/sim.8443. MR4067763
van Oudenhoven, F., Swinkels, S., Ibrahim, J. and Rizopoulos, D. (2020). A marginal estimate for the overall treatment effect on a survival outcome within the joint modeling framework. Stat Med 39(28) 4120–4132. https://doi.org/10.1002/sim.8713. MR4175019
Watanabe, S. (2010). Asymptotic equivalence of Bayes cross validation and widely applicable information criterion in singular learning theory. Journal of Machine Learning 11 3571–3594. MR2756194