The Cow's Milk-related Symptom Score (CoMiSS™) is a scoring system that reflects the appearance and intensity of symptoms possibly related to consumption of cow's milk. The original tool was recently updated by changing the cut-off, and the stool scale and by adding angioedema. There is no data available regarding the natural evolution of CoMiSS in infants with no cow's milk allergy (no-CMA) or a comparison between original and updated CoMiSS values. We determined the original and the updated CoMiSS in infants not diagnosed with cow's milk allergy. The evolution of CoMiSS during the first year of life was assessed repetitively during predefined check-ups at 1.5, 3, 4, 6, 8, 10, and 12 months. The original and updated scores were compared with the Wilcoxon Signed-Rank Test. We also tested the impact of feeding type, age, gender, and order in the family on the CoMiSS. One hundred and twenty-two infants were included. CoMiSS values during the first year of life showed an inverse relation to age. The difference in CoMiSS between the original and updated versions was significant at 6,8,10, and 12 months (p < 0.001), related to the switch from the Bristol Stool Form Scale to the Brussels Infants and Toddlers Stool Scale (BITSS). The difference between both versions of CoMiSS was not significantly different in infants < 6 months (p = 0.999 at 1.5 and 4 months, and p = 0.586 at 3 months, respectively).Conclusion: CoMiSS decreases with age during the first year of life. While there is no difference between the two CoMiSS versions in healthy infants under 6 months of age, the CoMiSS value in the updated version is lower than the original 1 in infants aged 6 to 12 months. What is known? • The Cow's Milk-related Symptom Score (CoMiSS) is a validated awareness tool for cow's milk allergy (CMA). • A CoMiSS of ≥ 10 indicates a risk for cow's milk allergy. What is new? • The natural evolution of CoMiSS in infants not diagnosed with CMA (no-CMA) shows an inverse relation to age. • There is no difference between the original and the updated CoMiSS versions in no-CMA-infants under six months of age, but the updated CoMiSS is lower in infants 6-12 months than the original one.

• Klíčová slova
• Awareness tool, CoMiSS, Cow’s milk allergy,
• MeSH
• alergie na mléko * diagnóza   MeSH
• kojenec MeSH
• lidé MeSH
• mléko škodlivé účinky   MeSH
• novorozenec MeSH
• stupeň závažnosti nemoci MeSH
• zvířata MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The Cow's Milk-related Symptom Score (CoMiSS) is an awareness tool for evaluating cow's milk-related symptoms. Previous studies have focused on providing CoMiSS values for healthy and symptomatic infants aged 0-6 months. However, there is a notable gap in the literature concerning CoMiSS values for infants older than 6 months. This cross-sectional study aimed to determine CoMiSS values in presumed healthy infants who have completed 6 months and are up to 12 months old, hereafter referred to as 6 to 12 months old. Physicians from six European countries prospectively determined CoMiSS values in infants attending well-child clinics. Exclusion criteria included preterm delivery, acute or chronic disease, and the consumption of a therapeutic formula, dietary supplements (except vitamins), or medication. The following information was collected: gestational age, gender, age, type of feed (breast milk or infant formula), and complementary feeding. Descriptive statistics were summarized with mean and standard deviation for normally distributed continuous variables, median and IQR for non-normally distributed variables, and differences in CoMiSS values were analyzed with appropriate tests. Data from 609 infants were obtained. The overall median (Q1-Q3) CoMiSS values were 3 (1-5). Significant differences were found across age groups (p < 0.001), but not across groups based on gender (p = 0.551) or feeding type (p = 0.880). Conclusions: This study provided CoMiSS values in presumed healthy infants aged 6-12 months. Additional studies should be conducted to establish the use of CoMiSS to assess cow's milk-related symptoms in infants 6 months and older. What is Known: • The Cow's Milk-related Symptom Score (CoMiSS) is an awareness tool for evaluating symptoms related to cow's milk. • CoMiSS values for presumed healthy infants aged 0-6 months infants are already available. What is New: • CoMiSS values in European infants aged 6-12 months are provided. • These CoMiSS values differed across various age groups but not across groups based on gender or feeding type.

• Klíčová slova
• Awareness, CoMiSS, Cow’s milk allergy, Infant feeding, Tool,
• MeSH
• alergeny MeSH
• alergie na mléko * diagnóza   MeSH
• kojenec MeSH
• lidé MeSH
• mateřské mléko MeSH
• mléko * MeSH
• náhražky mateřského mléka MeSH
• novorozenec MeSH
• průřezové studie MeSH
• skot MeSH
• zvířata MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• novorozenec MeSH
• skot MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• alergeny MeSH