Outcome	High risk of bias (category A)a	High risk of bias (category D)b	High risk of bias (category E)c	High risk of bias (category G)d
Barczynski 2012	N/A
Chi 2005	All‐cause mortality				x
Jarhult 2005	All‐cause mortality				x
	Rate of recurrent hyperthyroidism		x
Witte 2000	All‐cause mortality				x
Muller 2001	N/A
aClear that outcome was measured and analysed; trial report states that outcome was analysed but only reports that result was not significant (Classification 'A', table 2, Kirkham 2010). bClear that outcome was measured and analysed; trial report states that outcome was analysed but no results reported (Classification 'D', table 2, Kirkham 2010). cClear that outcome was measured but not necessarily analysed; judgement says likely to have been analysed but not reported because of non‐significant results (Classification 'E', table 2, Kirkham 2010). dUnclear whether the outcome was measured; not mentioned but clinical judgement says likely to have been measured and analysed but not reported on the basis of non‐significant results (Classification 'G', table 2, Kirkham 2010). N/A: not applicable; ORBIT: Outcome Reporting Bias In Trials.