Mean abundance ratios and rms scatters for [Sc/Fe], [V/Fe], and [Zn/Fe] in NGC 6388 from the present study (red points with errorbars) and in NGC 6388 (orange points), NGC 6441 (black points), NGC 5927 (light green points), and NGC 6496 (dark green points) from Minelli et al. (2021b). Empty grey circles are field disc and bulge stars from Adibekyan et al. (2012), Battistini & Bensby (2015), Bensby et al. (2005, 2014, 2017), Bihain et al. (2004), Brewer et al. (2016), da Silveira et al. (2018), Delgado-Mena et al. (2017), Gratton et al. (2003), Ishigaki et al. (2012, 2013), Lomaeva et al. (2019), Lucey et al. (2019), and Reddy et al. (2003, 2006). Open blue circles and filled violet circles are the high-α and low-α stars in the local sample by Nissen & Schuster (2011).