Dataset to accompany the manuscript "Use of In Vivo Imaging and Physiologically-Based Kinetic Modelling to Predict Hepatic Transporter Mediated Drug–Drug Interactions in Rats" by Nicola Melillo, Daniel Scotcher, J. Gerry Kenna, Claudia Green, Catherine D. G. Hines, Iina Laitinen, Paul D. Hockings, Kayode Ogungbenro, Ebony R. Gunwhy, Steven Sourbron, John C. Waterton, Gunnar Schuetz, and Aleksandra Galetin (referred to as the 'Six Test Compounds' study). data.zip After extracting the contents within the data.zip folder, the MRI signal data acquired in this study are provided in csv format and can be found inside the data/SixTestCompounds/01_signals subfolder. Each csv file contains the liver and spleen region of interest (ROI) time curve data for a single rat at a specific site and day, after administration of the test compound of interest. The corresponding filename for each file is formatted as a string containing study descriptors (metadata) separated by underscores, i.e., filename = compound_site_RatNumber_dayNumber_dataType, e.g., Asunaprevir_E_Rat2_2_Signals. results.zip The results and figures relating to this manuscript were created using the outputs contained in results/SixTestCompounds/2022-09-01. 01_model_ouputs contains all outputs generated as a result of the tracer kinetic model fitting. Within this, plotted signal time curves for each acquistion per rat may be found in figures/per_rat, while average deltaR1 curves per drug may be found in figures/per_drug. All estimated parameter variables from the fitting are stored in all_parameters.csv. The folder relaxation_rates_and_signals contains the fitted MRI signal data in a similar format to the original csv data in data/01_signals. Additional columns have been included showing the MRI signals converted to R1. 02_effect_sizes contains results of the statistical analysis performed on the tracer kinetic modelling output. This is summarised in tabular format in effect_sizes.csv, while graphical distributions are provided within the figures/ folder. fit_errors.txt contains an ID list for any computational fitting errors found during quality control of the tracer kinetic modelling.