Top panel: difference between Hα attenuations derived from the ratio of IR/Hα and those obtained using the Balmer decrement as a function of galaxy axial ratio. Solid and dashed black lines correspond to the mean and 1σ values, (0.05 ± 0.43) mag, after applying a rejection of 4σ. Because of the good agreement between both attenuations computed from different methods, we can safely assume that our Balmer decrement attenuations yield proper results. Besides, we do not find any systematic residuals against the axial ratio parameter associated with highly-inclined galaxies. Bottom panel: A(Hα) derived from the Balmer decrement as a function of the axial ratio (used as a proxy for inclination). Gray shadow corresponds to the 1σ intervals around the mean value showed in black solid line.