Table 3.

Estimated effects of the intervention by incentive arms and the incremental effect of outcome-based incentive^a (N = 240)

Source: Author calculations using the data collected from the study

	Incentive arms		Incremental effect of outcome-based vs. process-based incentives
	Process	Outcome	Estimate	[95% CI]
Primary outcome
Mean change in HbA1c at month 6	− 1.04	− 1.10	− 0.05	[− 0.42 to 0.31]
Secondary outcomes
Mean no. of glucose readings within acceptable range (out of 3 tests) during the last week of intervention	0.44	0.51	0.07	[− 0.21 to 0.34]
Mean no. of glucose readings (out of 3 tests) during the last week of intervention	1.20	1.14	− 0.06	[− 0.45 to 0.32]
Mean no. of medication adherent days during the last week of intervention	2.02	1.38	− 0.64	[− 1.32 to 0.04]
Mean no. of physically active days during the last week of intervention	3.12	1.76	− 1.37	[− 2.13 to −0.60]
Mean incentive payout during the last week of intervention	5.43	6.21	0.79	[− 1.62 to 3.19]
Mean time (in minutes) taken by the intervention during the last week of intervention	15.74	12.91	− 2.84	[− 4.84 to −0.83]
Exploratory outcomes
Proportion of participants who titrated up their oral medication during the intervention	0.43	0.36	− 0.08	[− 0.22 to 0.07]
Proportion of participants who switched to insulin treatment during the intervention	0.05	0.05	0.00	[− 0.07 to 0.07]
Mean change in EQ-5D-5L at month 6	0.03	− 0.01	− 0.04	[− 0.07 to −0.004]
Mean change in BIPQ at month 6	− 0.78	− 3.09	− 2.31	[− 4.92 to 0.31]
Mean change in BIPQ Treatment Control score at month 6	0.35	0.51	0.16	[− 0.42 to 0.73]
Mean change in SMBG score at month 6	0.49	0.51	0.02	[0.10 to 0.14]
Mean change in BMQ Specific score at month 6	0.06	0.43	0.37	[− 0.90 to 1.64]
Additional outcomes
Proportion of participants who had improvement in HbA1c at month 6	0.82	0.80	− 0.02	[− 0.14 to 0.11]

BIPQ Brief Illness Perception Questionnaire, BMQ Beliefs about Medication Questionnaire, CI confidence interval, EQ-5D-5L European Quality of Life–5 Dimensions–5 Levels, HbA1c glycated hemoglobin, SMBQ Self-Monitoring of Blood Glucose

^aCalculated as the difference in change from baseline at month 6 between that adherence outcome and process groups