First, the AEP (Appropriateness Evaluation Protocol) is an instrument to measure a hospital's operating efficiency with respect to acute patients, not specific clinical appropriateness. Consequently, I do not consider the lack of agreement between this tool and the judgement of a panel of experts to be remarkable: the AEP tool measures provision levels whereas the panel expressed a clinical opinion. Second, the quality of clinical documentation may dramatically influence the appropriateness of services; appropriateness tends to be underestimated in retrospective surveys. Lastly, the panel of experts seems to have based its judgement on a methodology that was only partially structured and that does not lend itself to standardization.