Trial ID	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
Altuntas 2003	All‐cause mortality	No	Yes	No	No
	Severe hypoglycaemic episodes	No	Yes	No	No
	All hypoglycaemic episodes	Yes	No	No	No
	Other adverse events	No	Yes	No	No
Bastyr 2000	All‐cause mortality	No	No	Yes	No
	Severe hypoglycaemic episodes	No	No	No	Yes
	All hypoglycaemic episodes	No	No	Yes	No
	HbA1c	No	No	Yes	No
	Health‐related quality of life	No	Yes	No	No
Dailey 2004	N/A
Hermann 2013	All‐cause mortality	No	No	Yes	No
	Severe hypoglycaemic episodes	No	No	No	Yes
NCT01650129	N/Ae
Pfützner 2013	All‐cause mortality	No	No	Yes	No
	Severe hypoglycaemic episodes	No	Yes	No	No
	All hypoglycaemic episodes	No	Yes	No	No
Rayman 2007	N/A
Ross 2001	Severe hypoglycaemic episodes	No	Yes	No	No
	Other adverse events	No	No	No	Yes
Z012 1997	All‐cause mortality	No	Yes	No	No
	Severe hypoglycaemic episodes	No	Yes	No	No
	Other adverse events	Yes	No	No	No
Z014 1997	All‐cause mortality	No	Yes	No	No
	Severe hypoglycaemic episodes	No	Yes	No	No
	Other adverse events	Yes	No	No	No
aClear that outcome was measured and analysed; trial report states that outcome was analysed but reports only 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 report no results ( Classification D, table 2, Kirkham 2010) cClear that outcome was measured but was 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 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) eNone of the data have been published, therefore assessment of risk of outcome reporting bias is not applicable. N/A: not applicable; HbA1c: glycosylated haemoglobin A1c; ORBIT: Outcome Reporting Bias In Trials