To ensure that student academic growth in a subject area is accurately captured, it is imperative that the underlying scale remains stable over time. As item parameter stability constitutes one of the factors that affects scale stability, NWEA® periodically conducts studies to check for the stability of the item parameter estimates for MAP® Growth™. This report documents a routine item parameter drift study with its primary purpose to check for the parameter stability of MAP Growth items. The items of interest in the study were those calibrated before May 24, 2013, when iterative grade range (IGR) was used to establish the calibration sample for MAP Growth item calibration. The study started by re-estimating the items of interest with test events administered between Fall 2017 and Spring 2019 to understand the extent of the drift in item parameter estimates, followed by identifying items that were likely unstable using the Robust Z method. The final step was to conduct an impact analysis that examined the impact of the observed item parameter drift on ability estimates for students. The item-level and test-level analysis results indicate that the MAP Growth measurement scales are remaining stable.