Comparison between the star formation rate determined using different tracers. SFR_{Hα + BD} stands for star formation rates determined using Hα luminosities corrected for Balmer decrement (using the gandalf dataset), and SFR_{Hα + 24 μm} corrected using the prescription of Calzetti et al. (2010) based on the 24 μm emission. SFR_{FUV + 24 μm} were determined using GALEX FUV data corrected for dust attenuation using the 24 μm emission following Hao et al. (2011), and SFR_radio using the 20 cm radio emission following Bell (2003) (see Appendix C). Black symbols are for galaxies with a spectroscopic σ [C(Hβ)] ≤ 0.1, red symbols for galaxies with σ [C(Hβ)] > 0.1. Filled dots are for galaxies with a normal gas content (HI - def ≤ 0.4), empty symbols for gas-poor objects (HI - def > 0.4). The black solid line shows the 1:1 relation, the black dotted line the bisector fit (and σ its dispersion) determined using the best quality sample (σ [C(Hβ)] ≤ 0.1).