1. 'Maziness' and 'window' are useful concepts to illustrate (to our clients) the notions of reliability and unbiasedness when time-dependency is subject of study. • Study design, measurement quality, intervention strategy and validity of sampling procedures are the recurrent key issues in every study, data-analysis comes later on. • Is ‘content reliability’ a strong enough concept to serve as a supervising criterion in strategies that warrant studies of high quality? Is it evaluable? Quantifiable? Unprejudiced? • The peer review should assess the design quality of the study as laid down in the study protocol before the study sets off, not afterwards if the results are offered for publication. It's too late then.