RESUMEN
INTRODUCTION AND AIMS: The prevalence of cow's milk protein allergy in the first year of life varies from 1.8 to 7.5%. The Cow's Milk-related Symptom Score (CoMiSS) was published in 2014 and facilitates the diagnosis of cow's milk protein allergy. It is not meant to replace the clinical diagnosis, but rather to guide the treating team in the diagnostic process and reduce unnecessary diets. The aim was to translate the CoMiSS from English to Spanish and culturally adapt and validate the resulting Spanish version. MATERIALS AND METHODS: An adaptation and validation study on the CoMiSS questionnaire was carried out in two phases: First, the CoMiSS was translated from English to Spanish, after which interrater reliability of the translated score was assessed. Second, interrater reliability tests were carried out on 32 pediatric patients under 7 years of age that were treated for the first time at the Food Allergy Clinic of the Hospital Italiano de Buenos Aires, were suspected of having cow's milk protein allergy, and had not received any treatment, within the time frame of May 2018 and May 2019. RESULTS: Thirty-two patients were evaluated, 14 of whom were females (45%), and the median patient age was 3 months (IQR 2-4). The median result of the first measurement of the scale was 7.0 (IQR 4.5-9.0) and the median of the second measurement was 5.0 (IQR 4.0-8.0). The final intraclass correlation coefficient was 0.80 (95% CI 0.63-0.9). CONCLUSION: The Spanish translation of the CoMiSS was comparable to the original English version, with excellent interrater reliability. This simple and little-known tool has the benefit of being a noninvasive, rapid, reliable, and easy-to-use strategy.