Table 1. Clinical scoring system used to determine the individualized activity of radioiodine to be administered (Mooney, 1994).

Score	Severity of clinical signs	Serum total T4 concentration (nmol/l)	Size of goiter	Total score and recommended activity
1	Mild	< 80	Palpable with difficulty	<9: <120 MBq
2	Mild to moderate	<100	1.0 × 0.5 cm	9–12: 120–150 MBq
3	Moderate	100–150	1.5 × 0.5 cm	>12: 150–180 MBq
4	Moderate to severe	150–400	>1.5 × 0.5 cm	If bilateral disease, the higher end of the dose interval was used
5	Severe	>400	Visible to naked eye