Flowchart of recruitment and participation in the 2015 Pelotas Birth Cohort Study. ^aCohort study catchment area, Pelotas urban area, Jardim America and Colônia Z3 (see Hallal et al. 2018¹). ^bTotal of 4164 singletons, 108 twins, 3 triplets born to 4219 mothers. ^cAll live children were considered eligible for reassessment at each follow-up. As in all previous Pelotas birth cohort studies, follow-up rates are calculated as (4275 less number losses less number refusals)/4275. ^dOnly firstborn children among multiple births were eligible for this assessment. WebCOVID-19 is the name of the follow-up assessment completed by internet during the COVID-19 pandemic, when cohort children were aged 5 years. Some descriptions of the prenatal assessments and children identified as born in 2015 in this flowchart have been clarified, compared with a previous presentation (Hallal et al., 2018).¹ Note also that in some publications we have referred to 4329 births occurring in 2015, which refers to all children included in the cohort (4275) as well as the 54 stillbirths who were not so included