1 London School of Paediatrics in Out-Of-Program placement for Research (OOP-R), London, UK; Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA. Electronic address: heidimakrinioti@gmail.com.
2 Department of Emergency Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA.
3 Department of Paediatrics, Turku University Hospital and Turku University, Turku, Finland; PEDEGO Research Unit, Medical Research Center, University of Oulu, Turku, Finland; Department of Pediatrics, Oulu University Hospital, Turku, Finland.