Column density of NH₂CHO versus column density of HNCO. Top panel: data points from the ALMAGAL survey found in this work with the best fit plotted as the middle solid line and the shaded green area showing the 68 percentile scatter in the data. Bottom panel: compares the fitted data in our work by studies from López-Sepulcre et al. (2015), Quénard et al. (2018), Ligterink et al. (2020), Law et al. (2021) and Colzi et al. (2021). The curves for López-Sepulcre et al. (2015), Quénard et al. (2018) and Colzi et al. (2021) are taken from the fit to abundances of NH₂CHO and HNCO and are normalized here as explained in the text: only slopes can be compared, not the absolute values.