Health & Medicinearticle2026-08-10

Percentiles for crying, regurgitation, stool consistency, and CoMiSSTM in presumed healthy infants

Open access0 citations

Abstract

Parents frequently consult health care professionals because of infant regurgitation, crying and stool consistency. The Cow’s Milk-related Symptom Score (CoMiSS TM ) is an awareness tool for cow’s milk allergy. We aimed to characterize the distribution of CoMiSS items in presumed healthy infants and developed centiles with these data. Data from 2500 infants (median age 5.3 months [Q1–Q3: 2.6–8.8]) across 10 countries were analyzed by pooling individual-level data. Age distribution differed between countries ( p < 0.001). Median (Q1; Q3) and mean (SD) total CoMiSS were 4 (2; 6) and 4 (2.6), respectively. Overall CoMiSS <10 was observed in 99%. Crying >3 hours/day occurred in 6.1% at 1–2 months, 4% between birth and 4 months, and <1.5% thereafter. Regurgitating > 5x/day occurred in 7–11% during the first 7 months (peak at 1–4 months: 16–17%) and decreased to <2–4% thereafter. Stool consistency accounted for 93.9% of the score. Atopic dermatitis and respiratory symptom scores are very low. CoMiSS is stable across age, with transiently higher crying and regurgitation scores below 4 months. CoMiSS ≥10 is uncommon in healthy infants. Age-specific CoMiSS centile charts provide a framework for interpreting common infant symptoms and identifying values warranting further evaluation. These data report on the prevalence of common manifestations in healthy infants and inform about normality according to age and different regions. Crying or distress and regurgitation scores are transiently more frequent during the first 4 months of life. Eczema and respiratory symptoms are seldom reported in presumed healthy infants. While caregivers and health care professionals consider regurgitation and crying or distress up to a certain limit as normal, atopic dermatitis and respiratory symptoms are not. These age-specific centile charts provide information on common infant symptoms and identify conditions that may warrant further evaluation.

// Source

View paper (DOI)Open access versionOpenAlexPediatric ResearchPublished 2026-08-10

Institutions: University of Colorado Denver, KU Leuven, University of Helsinki, Vrije Universiteit Brussel, New York University, Université Paris Cité, Helsinki University Hospital, University of Indonesia, Masaryk University, Medical University of Warsaw, University of Naples Federico II, University of Warmia and Mazury in Olsztyn, Universidade Federal de Sergipe, Schneider Children's Medical Center, Children's Hospital Colorado, Instituto de Investigación Sanitaria La Fe, Vietnam National Children's Hospital, Menoufia University, University of Insubria, Ospedale Filippo Del Ponte Varese, Institut Marcel Mauss