Study	Reason for exclusion
Carper 2014	Not a randomised controlled trial
Chiu 2016	Less than 6 months follow‐up for diabetes‐related distress. No specific adverse events are reported
Fisher 2014	Not a randomised controlled trial
Fonda 2009	Data of participants with both type 1 and 2 diabetes mellitus are included and no response was received on the request for separate data
Friis 2016	Less than 6 months follow‐up. No specific adverse events are reported within the 3‐month post intervention
Gabbay 2006	Data of participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data
Heisler 2010	Similar psychological interventions with only a difference in the methods of execution. The type of diabetes was not specified
Heisler 2014	Similar psychological interventions with only a difference in the methods of execution. The type of diabetes was not specified
Imazu 2015	Not a randomised controlled trial. No specific adverse events are reported
Izquierdo 2003	Similar psychological interventions with only a difference in the methods of execution; participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data
Jung 2015	Less than 6 months follow‐up. No specific adverse events are reported
Lee 2014	Hospitalisation for cardiac surgery
MacPhail 2014	Less than 6 months follow‐up. No specific adverse events are reported
Mantwill 2015	Less than 6 months follow‐up. No specific adverse events are reported
McMahon 2012	Similar psychological interventions: all were cognition‐focused; participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data
Munshi 2013	Participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data
Nobis 2015	Less than 6 months follow‐up. No specific adverse events are reported
Safford 2015	Similar psychological interventions: both were emotion‐cognition: peer coaches plus brief education compared with brief education alone
Samuel‐Hodge 2008	Not a randomised controlled trial
Schoevers 2013	Participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data. Less than 6 months follow‐up; no reporting on adverse events.
Siminerio 2013	Similar psychological interventions: both were cognition‐focused; participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data.
Simson 2008	Participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data. Less than 1 month follow‐up
Sinclair 2013	Less than 6 months follow‐up. No specific adverse events are reported
Skinner 2010	Not a randomised controlled trial, descriptive statistics on prevalence and persistence of depressive symptoms
Surwit 2002	Did not use the specified diabetes‐related distress scales
Tang 2014	Similar psychological interventions: both were cognition‐focused
Tang 2015	Similar emotion‐cognition interventions: 3‐month diabetes self‐management education programme versus ongoing diabetes self‐management support. The latter has extended peer‐support
Tovote 2014	Participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data. Less than 6 months follow‐up
Trief 2011	Diabetes‐related distress was not reported as measured with the 2 instruments specified in inclusion criteria for this review
Van Bastelaar 2011	Participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data
Van Bastelaar 2012	Not a randomised controlled trial
Van Son 2013	Participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data
Van Son 2014	Participants with both type 1 and 2 diabetes mellitus are included; no response was received on the request for separate data
Welch 2011a	Similar psychological interventions: both were cognition‐focused
Welch 2011b	Similar psychological interventions: both were cognition‐focused
Whittemore 2005	Not a randomised controlled trial
Zagarins 2012	Similar psychological interventions: both were cognition‐focused