Comparison 2. Cognition‐focused versus enhanced usual care.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Diabetes‐related distress (with types of setting subgroup)	4	2233	Std. Mean Difference (IV, Random, 95% CI)	‐0.03 [‐0.11, 0.06]
1.1 Community‐based studies	3	2099	Std. Mean Difference (IV, Random, 95% CI)	‐0.03 [‐0.11, 0.06]
1.2 Hospital‐based studies	1	134	Std. Mean Difference (IV, Random, 95% CI)	‐0.04 [‐0.37, 0.30]
2 Diabetes‐related distress (with types of intervention subgroup)	4	2233	Std. Mean Difference (IV, Random, 95% CI)	‐0.03 [‐0.11, 0.06]
2.1 Longer and more advanced interventions	2	1275	Std. Mean Difference (IV, Random, 95% CI)	‐0.06 [‐0.19, 0.08]
2.2 Brief and simple interventions	2	958	Std. Mean Difference (IV, Random, 95% CI)	0.00 [‐0.13, 0.13]
3 Diabetes‐related distress (with age subgroup)	4	2233	Std. Mean Difference (IV, Random, 95% CI)	‐0.01 [‐0.09, 0.08]
3.1 Age < 60 years	3	1347	Std. Mean Difference (IV, Random, 95% CI)	‐0.02 [‐0.17, 0.12]
3.2 Age ≥ 60 years	1	886	Std. Mean Difference (IV, Random, 95% CI)	‐0.00 [‐0.13, 0.13]
4 Health‐related quality of life	1		Std. Mean Difference (IV, Fixed, 95% CI)	Totals not selected
5 Adverse events	2	597	Risk Ratio (M‐H, Random, 95% CI)	1.29 [0.39, 4.31]
6 Self‐efficacy (with types of intervention subgroup)	2	1018	Std. Mean Difference (IV, Random, 95% CI)	‐0.04 [‐0.39, 0.31]
6.1 Longer and more advanced interventions	1	884	Std. Mean Difference (IV, Random, 95% CI)	0.11 [‐0.02, 0.24]
6.2 Brief and simple interventions	1	134	Std. Mean Difference (IV, Random, 95% CI)	‐0.26 [‐0.60, 0.08]
7 Self‐efficacy (with age subgroup)	2		Std. Mean Difference (IV, Random, 95% CI)	Subtotals only
7.1 Age < 60 years	2	1018	Std. Mean Difference (IV, Random, 95% CI)	‐0.04 [‐0.39, 0.31]
8 HbA1c (with types of setting subgroup)	4	1958	Mean Difference (IV, Random, 95% CI)	0.03 [‐0.18, 0.24]
8.1 Community‐based studies	3	1837	Mean Difference (IV, Random, 95% CI)	‐0.02 [‐0.18, 0.14]
8.2 Hospital‐based studies	1	121	Mean Difference (IV, Random, 95% CI)	0.44 [0.00, 0.88]
9 HbA1c (with types of intervention subgroup)	4	1958	Mean Difference (IV, Random, 95% CI)	0.03 [‐0.18, 0.24]
9.1 Longer and more advanced interventions	2	1013	Mean Difference (IV, Random, 95% CI)	‐0.15 [‐0.50, 0.20]
9.2 Brief and simple interventions	2	945	Mean Difference (IV, Random, 95% CI)	0.19 [‐0.18, 0.55]
10 HbA1c (with age subgroup)	4	1958	Mean Difference (IV, Random, 95% CI)	0.03 [‐0.18, 0.24]
10.1 Age < 60 years	2	945	Mean Difference (IV, Random, 95% CI)	0.19 [‐0.18, 0.55]
10.2 Age ≥ 60 years	2	1013	Mean Difference (IV, Random, 95% CI)	‐0.15 [‐0.50, 0.20]
11 Systolic blood pressure (with types of interventions subgroup)	3	1085	Mean Difference (IV, Random, 95% CI)	0.40 [‐1.70, 2.50]
11.1 Longer and more advanced interventions	1	127	Mean Difference (IV, Random, 95% CI)	‐1.30 [‐6.02, 3.42]
11.2 Brief and simple interventions	2	958	Mean Difference (IV, Random, 95% CI)	0.82 [‐1.53, 3.17]
12 Diastolic blood pressure (with types of interventions subgroup)	3	1085	Mean Difference (IV, Random, 95% CI)	1.52 [‐0.68, 3.72]
12.1 Longer and more advanced interventions	1	127	Mean Difference (IV, Random, 95% CI)	5.0 [0.59, 9.41]
12.2 Brief and simple interventions	2	958	Mean Difference (IV, Random, 95% CI)	0.54 [‐0.71, 1.79]
13 All‐cause mortality	2	1822	Risk Ratio (M‐H, Random, 95% CI)	0.69 [0.23, 2.07]
13.1 At more than 12 months	1	824	Risk Ratio (M‐H, Random, 95% CI)	0.30 [0.01, 7.23]
13.2 At less than 12 months	2	998	Risk Ratio (M‐H, Random, 95% CI)	0.77 [0.24, 2.48]
14 All‐cause mortality (with age subgroup)	3	1488	Odds Ratio (M‐H, Random, 95% CI)	1.25 [0.27, 5.79]
14.1 Age < 60 years	2	1369	Odds Ratio (M‐H, Random, 95% CI)	1.25 [0.08, 18.55]
14.2 Age ≥ 60 years	1	119	Odds Ratio (M‐H, Random, 95% CI)	1.5 [0.24, 9.32]