Table 1.

Number of patients from hospital participating in the study.

Hospital Name, City	Number of Patients
Upper Silesian Child Health Centre, Katowice	9
University Child Hospital, Lublin	9
University Hospital, Poznan	7
University Hospital Nr 1, Szczecin	4
University Child Hospital, Białystok	4
University Hospital, Rzeszów	3
Copernicus Hospital, Gdansk	2
University Clinical Centre of the Medical University of Warsaw	2
University Children’s Hospital of Cracow	2
University Clinical Hospital in Wroclaw	2
Children’s Memorial Health Institute, Warsaw	1