Schrama, E.

limit amplitude study interval percentile month age groups children measurement sampling rate heart group paediatric sex di fferences fidence intervals 0·16 fference qrs duration 0·11 davignon value 0·13 paediatric ecg sampling duration heart rate 0·10 0·18 table 0·20 0·15 0·12 0·22 ecg measurements 0·17 1–3 0·30 qtc interval fidence age-dependent percentile curves eur heart j q-wave amplitude 16 years 0·09 0·19 0·24 0·21 age group percentile estimates 1200 hz r-wave precordial hypertrophy p-wave amplitude di fferences parameter amplitude di fferences 0·23 0·34 right atrial hypertrophy electrocardiogram april macfarlane issue 12–16 qtc interval prolongation 0·4 analysis curve 0·25 3 years fi ndings 500 hz qt interval 3–5 change estimate r-wave amplitude q-wave e ffects