The current program of research seeks to investigate new and emerging statistical models to develop accurate and efficient instruments that measure the latent relationship between internalising (eg. depression, anxiety), externalising (eg. substance use, anti-social and conduct disorder) and thought disorders (eg. psychosis).
A growing body of empirical evidence has questioned the validity of categorical diagnostic instruments. Converging lines of evidence suggest that models of psychopathology that measure multiple disorders through the use of broad dimensional spectra offer a significant improvement to psychiatric research and clinical practice. This model is commonly referred to as a dimensional-spectrum model. In order to facilitate the use of dimensional models to measure the broad spectra of psychopathology there is a growing need for new assessment tools that measure the dimensionality of psychiatric disorders. Previously, dimensional instruments for individual disorders have been developed however no study has examined the possibility of constructing a tool that measures the complex latent relationship between putatively distinct disorders using a dimensional-spectrum model. Advances in measurement theory, particularly multidimensional Item Response Theory (IRT), offer innovative ways to measure broad dimensional constructs. These methods can be utilised for the development of efficient and accurate diagnostic tools through the use of computerised adaptive testing.
The current research program aims to develop and test an innovative and novel approach for measuring psychiatric disorders in community and clinical populations using a dimensional-spectrum model as the guiding theoretical framework.