Scaling relations obtained when including or excluding clusters of the XMM-Newton sample. Left: Comparison of the scaling relation obtained with the Chandra sample restricted to the 56 clusters present in both Chandra and XMM-Newton samples (black line with uncertainty and intrinsic scatter) and the relation obtained with the full Chandra sample (green line). Right: Comparison of the scaling relation obtained with the Chandra sample restricted to the 110 clusters present in the Chandra sample and absent from the XMM-Newton sample (black line with uncertainty and intrinsic scatter) and the relation obtained with the full Chandra sample (green line).