Table 3.
Effectiveness of the intervention on coprimary outcomes.
| Coprimary outcomes and analysis models and Arms | Between arm differences at 6 months (95% CI) | P value | Between arm differences at 12 months (95% CI) | P value | Estimated mean changes between baseline and 6 months (95% CI)a | P value | Estimated mean changes between baseline and 12 months (95% CI)a | P value | ||
| Glycated hemoglobin (%) | ||||||||||
|
|
Primary (Intention-to-treat) modelb | |||||||||
|
|
|
Intervention | 0.06 (−0.35 to 0.47) | .78 | −0.04 (−0.45 to 0.36) | .84 | −0.20 (−0.49 to 0.09) | .17 | −0.33 (−0.62 to −0.04) | .03 |
|
|
|
Control | Reference | N/Ac | Reference | N/A | −0.26 (−0.55 to 0.03) | .08 | −0.28 (−0.57 to 0.00) | .05 |
|
|
Adjusted modeld | |||||||||
|
|
|
Intervention | 0.06 (−0.35 to 0.46) | .79 | −0.04 (−0.44 to 0.37) | .87 | −0.20 (−0.49 to 0.09) | .18 | −0.32 (−0.61 to −0.03) | .03 |
|
|
|
Control | Reference | N/A | Reference | N/A | −0.25 (−0.54 to 0.03) | .09 | −0.28 (−0.57 to 0.00) | .05 |
|
|
Per-protocol modele | |||||||||
|
|
|
Intervention | −0.05 (−0.47 to 0.37) | .81 | −0.14 (−0.56 to 0.28) | .52 | −0.26 (−0.59 to 0.07) | .12 | −0.40 (−0.73 to −0.06) | .02 |
|
|
|
Control | Reference | — | Reference | — | −0.21 (−0.47 to 0.05) | .11 | −0.26 (−0.51 to −0.00) | .05 |
| Health Related Quality of Life: Assessment of Quality of Life-8D utility score | ||||||||||
|
|
Primary (Intention-to-treat) modelb | |||||||||
|
|
|
Intervention | 0.05 (0.01 to 0.08) | .006 | 0.04 (0.00 to 0.07) | .039 | 0.04 (0.01 to 0.07) | .002 | 0.04 (0.01 to 0.06) | .007 |
|
|
|
Control | Reference | N/A | Reference | N/A | −0.01 (−0.03 to 0.02) | .48 | 0.00 (−0.03 to 0.02） | .92 |
|
|
Adjusted modeld | |||||||||
|
|
|
Intervention | 0.05 (0.01 to 0.08) | .005 | 0.03 (0.00 to 0.07) | .047 | 0.04 (0.01 to 0.06) | .002 | 0.03 (0.01 to 0.06) | .009 |
|
|
|
Control | Reference | N/A | Reference | N/A | −0.01 (−0.03 to 0.01) | .46 | −0.00 (−0.02 to 0.02) | .93 |
|
|
Per-protocol modele | |||||||||
|
|
|
Intervention | 0.06 (0.02 to 0.09) | .002 | 0.06 (0.02 to 0.09) | .003 | 0.05 (0.02 to 0.08) | .001 | 0.05 (0.02 to 0.08) | .001 |
|
|
|
Control | Reference | N/A | Reference | N/A | −0.01 (−0.03 to 0.01) | .49 | −0.01 (−0.03 to 0.02) | .63 |
aMean changes in outcomes were estimated based on the linear mixed-effect regression model.
bFor HbA1c, the intraclass correlation coefficient (ICC) for the primary model was 0.551 (95% CI 0.465-0.634). For HRQoL, the ICC for the unadjusted model was 0.847 (95% CI 0.806-0.880). Number of participants with valid data at each time point: n for HbA1c (intervention vs control): 93 vs 94 at baseline, 78 vs 78 at 6 months, and 77 vs 79 at 12 months. Number of participants at each time point for HRQoL (intervention vs control): 93 vs 94 at baseline, 67 vs 77 at 6 months, and 60 vs 78 at 12 months.
cN/A: not applicable.
dThe adjusted model adjusted baseline values of variables that were either imbalanced by intervention allocation by chance (baseline age and depression score) or associated with loss to follow-up (baseline AQoL-8D utility value and HADS Anxiety score).
eThe per-protocol analysis considered participants who had completed more than 6 chats with Laura as following the study protocol.