Estimating and interpreting psychometric networks in neuropsychology: A tutorial with conceptual extensions

Network psychometrics has emerged as a promising framework for modelling the structure of neuropsychological data, offering a complementary perspective to traditional latent variable approaches or single test approaches. In neuropsychology, test performance is rarely interpreted in isolation, but rather as reflecting interacting cognitive processes. Network models provide a formal framework to represent these interdependencies by estimating conditional associations among observed variables. The present article provides a comprehensive tutorial on the estimation and interpretation of psychometric networks in neuropsychology. First, we offer a step-by-step guide to estimating a cross-sectional Gaussian Graphical Model (GGM), including data preparation, model selection, regularization, visualization and stability assessment, using a neuropsychological dataset from patients with Alzheimer's disease. Particular emphasis is placed on best practices for ensuring reproducibility and robustness, including the use of bootstrap procedures and reporting standards. Second, we outline key methodological extensions, including Exploratory Graph Analysis for dimensionality assessment, joint graphical models and Network Comparison Test for group comparisons, mixed graphical models for heterogeneous data and longitudinal network approaches. These methods are presented conceptually to illustrate how network analysis can be extended beyond basic cross-sectional applications. Finally, we discuss the strengths and limitations of network psychometrics in neuropsychology. We emphasize that network models represent statistical associations among observed test scores rather than direct representations of cognitive architecture and that their interpretation requires theoretical caution. When applied with methodological rigour and conceptual restraint, network analysis provides a flexible and integrative framework for investigating the structure of cognitive systems.