Study ID	Intervention(s) and comparator(s)	Participants included in analysis (N)	Participants with a specific adverse event (description)	Participants with at least one specific adverse events (N)	Participants with at least one specific adverse event (%)
Albino 2010	I1: 0.1 mg rhTSH + radioiodine (1.11 GBq)	8	(a) hypothyroidism (b) mild cervical discomfort, localised pain, and palpitations (c) goitre enlargement and/or compressive symptoms with respiratory difficulty	(a) 3 (b) 1 (c) 3	(a) 37.5 (b) 12.5 (c) 37.5
	I2: 0.01 mg rhTSH + radioiodine (1.11 GBq)	6	(a) hypothyroidism (b) mild cervical discomfort, localised pain and palpitations (c) goitre enlargement, or compressive symptoms, or both, with respiratory difficulty	(a) 3 (b) 1 (c) 2	(a) 50 (b) 16.7 (c) 33.3
	C: placebo and radioiodine (1.11 GBq)	8	(a) hypothyroidism (b) mild cervical discomfort, localised pain and palpitations (c) goitre enlargement, or compressive symptoms, or both, with respiratory difficulty	(a) 2 (b) 1 (c) 2	(a) 25 (b) 12.5 (c) 25
Bonnema 2007	I: 0.3 mg rhTSH + radioiodine (aiming for a thyroid dose of 100 Gy)	14	—	—	—
	C: isotonic saline + radioiodine (aiming at a thyroid dose of 100 Gy)	15	—	—	—
Cubas 2009	I1: 0.005 mg rhTSH + radioiodine (1.11 GBq)	9	(a) symptoms of hyperthyroidism, such as palpitation, anxiety, headache, or asthenia (b) enlargement of the thyroid without compressive symptoms, moderate cervical pain	(a) 6 (b) 6	(a) 66.6 (b) 66.6
	I2: 0.1 mg rhTSH + radioiodine (1.11 GBq)	9	(a) symptoms of hyperthyroidism, such as palpitation, anxiety, headache, or asthenia (b) enlargement of the thyroid without compressive symptoms, or moderate cervical pain	(a) 2 (b) 3	(a) 22.2 (b) 33.3
	C: placebo and radioiodine (1.11 GBq)	10	(a) symptoms of hyperthyroidism, such as palpitation, anxiety, headache, or asthenia (b) enlargement of the thyroid without compressive symptoms, or moderate cervical pain	(a) 4 (b) 0	(a) 40 (b) 0
Fast 2010	I: 0.1 mg rhTSH + radioiodine (50 Gy)	60	(a) hyperthyroidism symptoms (b) cervical discomfort or pain (c) biochemical hyperthyroidism (d) mild, transient thyroid‐associated ophthalmopathy (e) permanent hypothyroidism (1‐year follow‐up) (f) therapeutic failure (i.e. failure to relieve goitre‐related symptoms, leading to subsequent thyroid surgery)	(a) 13 (b) 5 (c) 33 (d) 2 (e) 7 (f) 4	(a) 21.7 (b) 8.3 (c) 55 (d) 3.3 (e) 11.7 (f) 6.7
	C: placebo + radioiodine (100 Gy)	30	(a) hyperthyroid symptoms (b) cervical discomfort/pain (c) biochemical hyperthyroidism (d) mild, transient thyroid‐associated ophthalmopathy (e) permanent hypothyroidism (1‐year follow‐up) (f) therapeutic failure (i.e. failure to relieve goitre‐related symptoms, leading to subsequent thyroid surgery)	(a) 7 (b) 4 (c) 19 (d) 0 (e) 2 (f) 2	(a) 23.3 (b) 13.3 (c) 63.3 (d) 0 (e) 6.7 (f) 6.7
Fast 2014	I1: 0.01 mg rhTSH + radioiodine (100 Gy)	30	(a) hyperthyroidism (b) hypothyroidism (c) thyroid pain (d) neck pain	(a) 8 (b) 10 (c) 0 (d) 3	(a) 26.7 (b) 33.3 (c) 0 (d) 10
	I2: 0.03 mg rhTSH + radioiodine (100 Gy)	33	(a) hyperthyroidism (b) hypothyroidism (c) thyroid pain (d) neck pain	(a) 11 (b) 15 (c) 1 (d) 6	(a) 33.3 (b) 45.5 (c) 3 (d) 18.2
	C: placebo and radioiodine (100 Gy)	32	(a) hyperthyroidism (b) hypothyroidism (c) thyroid pain (d) neck pain	(a) 2 (b) 4 (c) 1 (d) 3	(a) 6.3 (b) 12.5 (c) 3.1 (d) 9.4
Nielsen 2006	I: 0.3 mg rhTSH + radioiodine (calculated based on thyroid size, thyroid 131I uptake, and 131I half‐life)	28	(a) hyperthyroid symptoms (b) cervical pain beyond 1 week (c) permanent hypothyroidism	(a) 10 (b) 3 (c) 16	(a) 35.7% (b) 10.7% (c) 57.1
	C: placebo + radioiodine (calculated based on thyroid size, thyroid 131I uptake, and 131I half‐life)	29	(a) hyperthyroid symptoms (b) cervical pain beyond 1 week (c) permanent hypothyroidism	(a) 6 (b) 2 (c) 3	(a) 20.7 (b) 6.9 (c) 10.3
—: denotes not reported 131I: radioactive iodine; C: comparator; GBq: giga Becquerel; Gy: Gray; I: intervention; rhTSH: recombinant human thyrotropin.