Abstract
Total length ( L T ) and mass measurements of 28 596 specimens of European chub Leuciscus cephalus , collected from a variety of waterways across Italy, were used to compute standard mass ( W s ) equations by both empirical percentile (EmP) and regression line percentile (RLP) methods. The use of the EmP W s equation [log 10 W s = −4·79 + 2·68log 10 L T + 0·10(log 10 L T ) 2 ] to compute relative mass ( W r ) of L. cephalus in Italy is suggested, as it was not influenced by length‐related bias ( L T range of application = 70–470 mm).