External validation and comparison of formulae estimating 24-h sodium intake from a fasting morning urine sample: - Vidal-Petiot, Emmanuelle; Joseph, Adrien; Resche-Rigon, Matthieu; d’ Ortho, Marie-Pia; Boutten, Anne; Mullaert, Jimmy; Mp, d' Ortho; Vrtovsnik, François; Pg, Steg; Steg, P.-H. Gabriel; Flamant, Martin (Journal of Hypertension, 2017)