Medical statistics may contribute to ameliorate research by improving the design of studies and identifying the optimal method for the analysis of results. Sometimes, nevertheless, it could be misemployed flawing the benefit potential. Allergic diseases pathogenesis is recognized to be systemic but global initiatives such as GINA and ARIA documents define allergic asthma and rhinitis as organ diseases; such an asymmetrical view raises a set of known and unknown confounding that could influence the quality of the process of evidence-based decision-making (topic symptomatic therapeutic interventions versus systemic pathogenetic interventions). This article shows the first scoring system for the assessment of atopic dermatitis lesions developed in the allergy-area. A four-step severity score (FSSS) was chosen in agreement with those developed for asthma and rhinitis in global initiatives, to avoid any further differences in evaluating the severity of allergic diseases. FSSS relates each step with the objective signs of the SCORAD and rates the disease course as intermittent or persistent. A devoted electronic program has been also framed to allow a quick and simple contemporary evaluation of the SCORAD Index (Section I) and of the FSSS (Section II); the program furthermore foresees a third section named ESAS (Extra Skin Allergic Signs) (Section III) in which it is possible to check whether organs other than the skin are involved by the allergic inflammation. The limitations potential generated by a misemployment of medical statistics for clinical trials designed to establish benefits rising from specific immunotherapy for allergic diseases have been also discussed extensively.