A Bayesian semi-parametric model for longitudinal growth and appetite phenotypes in children

TL;DR

This paper introduces a Bayesian semi-parametric model that jointly analyzes longitudinal growth and eating behaviour data in children, revealing subgroups and developmental patterns linked to obesity risk.

Contribution

It extends the Partial Credit Model with Bayesian nonparametrics to jointly model growth and eating behaviours over time, capturing heterogeneity in developmental trajectories.

Findings

Identifies clinically relevant subgroups based on growth and eating behaviours.

Demonstrates the model's ability to uncover associations between early eating habits and growth patterns.

Provides a flexible framework for analyzing complex longitudinal childhood data.

Abstract

This study develops a Bayesian semi-parametric model to examine the longitudinal growth and appetite phenotypes in children from the GUSTO cohort, with a focus on understanding the relationship between eating behaviours and growth outcomes over time. While eating behaviours, such as picky eating, have been shown to influence future weight and obesity risk, their developmental patterns and associations with growth trajectories remain under-explored. This work addresses these gaps by modelling longitudinal data, including both growth metrics (e.g., BMI) and eating behaviours (e.g., Child Eating Behaviour Questionnaire, CEBQ), across multiple time points. We extend the Partial Credit Model, commonly used for questionnaire data analysis, to accommodate repeated measurements and incorporate covariates. The growth outcomes are modelled using flexible splines regression. The two components of the model are linked through a shared Bayesian nonparametric prior distribution, specifically a Normalized Generalized Gamma process, allowing to identify clinically relevant subgroups. This joint modelling approach offers a more nuanced understanding of how early eating behaviours relate to growth patterns and developmental outcomes, providing insights into childhood obesity risk.