I'm currently working on a project involving group-based trajectory modelling and am seeking advice on handling multi-level factors within this context. Specifically, I'm interested in understanding the following:

  • Multi-Level Factors in Trajectory Modelling: How can multi-level factors (e.g., individual-level and group-level variables) be effectively addressed in group-based trajectory modelling? Are there specific methods or best practices recommended for incorporating these factors?
  • Flexmix Package: I’ve come across the Flexmix package in R, which supports flexible mixture modelling. How can this package be utilised to handle multi-level factors in trajectory modelling? Are there specific advantages or limitations of using Flexmix compared to other methods?
  • Comparison with Other Approaches: In what scenarios would you recommend using Flexmix over other trajectory modelling approaches like LCMM, TRAJ, or GBTM? How do these methods compare in terms of handling multi-level data and providing accurate trajectory classifications?
  • Adjusting for Covariates: When identifying initial trajectories (e.g., highly adherent, moderately adherent, low adherent), is it necessary to adjust for covariates such as age, sex, and socioeconomic status (SES)? Or is focusing on adherence levels at each time point sufficient for accurate trajectory identification? What are the best practices for incorporating these covariates into the modelling process?
  • Any insights, experiences, or references to relevant literature would be greatly appreciated!

    Similar questions and discussions