Table 4.
GEE models for the comparison of outcome variables over the study period (N = 128)
| Variables | Group-difference | Time1-difference | Time2-difference | Group*Time1-difference | Group*Time2-difference | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| β (95% CI) | p value | β (95% CI) | p value | β (95% CI) | p value | β (95% CI) | p value | β (95% CI) | p value | |
| HbA1c (%) |
−0.20 (− 0.62, 0.23) |
0.365 | – | – |
0.18 (0.05, 0.30) |
0.006 | – | – |
−0.32 (− 0.49, − 0.14) |
< 0.001 |
| Diabetes self-management behaviors (SDSCA) | ||||||||||
| General diet |
0.30 (−0.38, 0.98) |
0.383 |
0.37 (−0.04, 0.77) |
0.075 |
0.31 (−0.08, 0.70) |
0.114 |
0.01 (−0.49, 0.51) |
0.967 |
0.19 (−0.32, 0.70) |
0.459 |
| Specific diet regarding intake of fruits and vegetables |
−0.04 (− 0.94, 0.86) |
0.934 |
−0.16 (− 0.62, 0.29) |
0.483 |
−0.12 (− 0.59, 0.36) |
0.635 |
1.02 (0.24, 1.80) |
0.011 |
0.98 (0.18, 1.78) |
0.016 |
| Specific diet regarding intake of high fat foods |
0.07 (−0.75, 0.88) |
0.875 |
−0.01 (− 0.48, 0.45) |
0.958 |
0.09 (−0.38, 0.55) |
0.717 |
0.83 (0.12, 1.55) |
0.023 |
0.50 (−0.20, 1.20) |
0.163 |
| Physical activity |
−0.15 (− 0.91, 0.62) |
0.702 |
0.10 (−0.27, 0.48) |
0.586 |
−0.15 (− 0.56, 0.26) |
0.473 |
0.15 (−0.31, 0.62) |
0.525 |
0.39 (−0.12, 0.90) |
0.132 |
| Blood glucose monitoring |
−0.25 (−1.02, 0.53) |
0.532 |
−0.03 (− 0.24, 0.17) |
0.751 |
−0.20 (− 0.51, 0.12) |
0.218 |
0.36 (−0.01, 0.72) |
0.057 |
0.64 (0.20, 1.08) |
0.004 |
| Foot care |
−0.17 (−1.1, 0.76) |
0.717 |
−0.04 (− 0.46, 0.39) |
0.863 |
−0.01 (− 0.46, 0.44) |
0.962 |
1.80 (1.05, 2.54) |
< 0.001 |
2.02 (1.27, 2.77) |
< 0.001 |
| Smoking status (non-smoker to smoker ratio) |
1.23 (0.58, 2.62) |
0.593 |
1.13 (0.85, 1.51) |
0.392 |
1.32 (0.91, 1.91) |
0.141 |
1.38 (0.85, 2.25) |
0.195 |
1.95 (0.95, 4.00) |
0.067 |
| Medication management |
0.56 (−0.43, 1.55) |
0.267 |
− 0.08 (− 0.27, 0.12) |
0.441 |
− 0.13 (− 0.33, 0.08) |
0.230 |
0.83 (0.25, 1.41) |
0.005 |
0.95 (0.31, 1.58) |
0.003 |
| Self-efficacy (DMSES) |
−3.60 (−15.71, 8.50) |
0.560 |
−2.90 (−5.73, −0.08) |
0.044 |
−3.43 (−6.47, −0.39) |
0.027 |
8.73 (3.34, 14.12) |
0.001 |
9.71 (4.03, 15.38) |
0.001 |
Note: β: difference in values; p value: the probability of a true null hypothesis; HbA1c Glycated Hemoglobin A, SDSCA Summary of Diabetes Self-Care Activities DMSES Diabetes Management Self-Efficacy Scale; Group-difference: Difference in indicator values between groups at baseline; Time-difference: Within group change in indicator values in the control group; Group*Time-difference: Additional change of the intervention group in indicator values compared to the control group; CI Confidential interval