Table 2.

Results from the subgroup analyses to assess whether surrogacy was moderated by baseline properties of the trials’ sample models

Parameter (Interaction of HbA1c difference and …)	Estimate	95% Confidence interval
Risk difference
Sample size	0.00054%	[− 0.00017%; 0.00124%]
Age at baseline	− 0.01501%	[− 0.05964%; 0.02962%]
Percentage of males	− 0.00422%	[− 0.01977%; 0.01133%]
Duration of diabetes	− 0.00317%	[− 0.03803%; 0.03169%]
HbA1c at baseline	− 0.07969%	[− 0.39406%; 0.23469%]
BMI at baseline	0.00407%	[− 0.03300%; 0.04114%]
Trial duration	− 0.00274%	[− 0.01123%; 0.00575%]
Log relative risk
Sample size	0.0004	[− 0.0004; 0.0013]
Age at baseline	− 0.0038	[− 0.0514; 0.0438]
Percentage of males	− 0.0115	[− 0.0236; 0.0006]
Duration of diabetes	0.0125	[− 0.0458; 0.0707]
HbA1c at baseline	− 0.1341	[− 0.3676; 0.0994]
BMI at baseline	− 0.0176	[− 0.0719; 0.0367]
Trial duration	− 0.0058	[− 0.0145; 0.0029]

The parameter estimates (with 95% confidence interval) of the interaction term of the HbA1c difference with the respective potential moderators are given