Expert opinion as 'validiation' of risk assessment applied to calf welfare

Background - Recently, a Risk Assessment methodology was applied to animal welfare issues in a report of the European Food Safety Authority (EFSA) on intensively housed calves. Methods - Because this is a new and potentially influential approach to derive conclusions on animal welfare issues, a so-called semantic-modelling type 'validation' study was conducted by asking expert scientists, who had been involved or quoted in the report, to give welfare scores for housing systems and for welfare hazards. Results - Kendall's coefficient of concordance among experts (n = 24) was highly significant (P