Oxygen abundances as determined from the strong-line calibration methods described in the Sect. 4.3 against the direct method oxygen abundance for ten regions in J0921 (from J20) and the Leo P HII region (taken from Skillman et al. 2013), with the single Leo P region having the lowest 12 + log(O/H)_direct. The dashed black line indicates where the derived abundances are equivalent to the direct, temperature-based values.