design: The qFit2 study examines the effects of FIT (EXTEL HEMO-AUTO MC) sample storage on the taxonomic abundance observed in human gut microbiome samples. Stool samples collected in FIT cartridges were processed on day 0, day 4, day 7 and day 14. DNA was extracted on the same day as sample processing. FIT cardridges for t=4, t=7 and t=14 were stored at RT until day 4, after which they were stored at 4 degrees C until sample processing, to mimic postage and sample processing conditions of FITs in cancer screening programmes. At time of processing, the FIT buffer was removed from the FIT cardridge, and homogenate was spun down and resuspended in 0.45ml of supernatant, after which DNA extraction took place. These samples were compared to samples collected with the standard method. The standard method consists of homogenising 5g of stool in 10ml of PBS/30% glycerol using gentleMACS; 0.45ml of homogenate is used for DNA extraction.