Primary Outcome | ||||
K-means Variability Group | Low Variability | Medium Variability | High Variability | Total |
Mean Value of HbA1c | Â | P for interaction: 0.05 | ||
One linear-regression model | 1.33 (1.14, 1.56) P < 0.01 | 1.14 (0.99, 1.30) P = 0.06 | 1.06 (0.90, 1.23) P = 0.49 | 1.16 (1.07, 1.27) P < 0.01 |
 Two-piecewise linear-regression model |  | |||
  Inflection point (K and 95%CI) (%) | 6.74 (6.57, 6.95) | 7.49 (7.34, 7.65) | 7.88 (7.68, 8.09) | 8.82 (8.17, 8.87) |
  <K Effect size β (95%CI) | 1.12 (0.70, 1.79) P = 0.63 | 0.88 (0.67, 1.15) P = 0.36 | 0.80 (0.54, 1.18) P = 0.27 | 1.18 (1.07, 1.31) P < 0.01 |
  >K Effect size β (95%CI) | 1.42 (1.13, 1.78) P < 0.01 | 1.38 (1.11, 1.71) P < 0.01 | 1.19 (0.96, 1.47) P = 0.11 | 1.08 (0.79, 1.47) P = 0.61 |
  P for Log-likelihood ratio test | 0.46 | 0.04 | 0.15 | 0.60 |
All-cause Mortality | ||||
K-means Variability Group | Low Variability | Medium Variability | High Variability | Total |
Mean Value of HbA1c | Â | P for interaction: 0.02 | ||
One linear-regression model | 1.23 (1.01, 1.51) P = 0.04 | 0.92 (0.76, 1.11) P = 0.38 | 0.86 (0.72, 1.03) P = 0.10 | 0.98 (0.88, 1.09) P = 0.65 |
 Two-piecewise linear-regression model |  | |||
  Inflection point (K and 95%CI) (%) | 5.99 (5.97, 6.21) | 7.44 (7.30, 7.59) | 7.86 (7.66, 8.06) | 6.11 (6.10, 6.43) |
  <K Effect size β (95%CI) | None | 0.49 (0.36, 0.69) P < 0.01 | 0.63 (0.42, 0.95) P < 0.01 | None |
  >K Effect size β (95%CI) | 1.19 (0.96, 1.47) P = 0.11 | 1.57 (1.19, 2.08) P < 0.01 | 1.01 (0.78, 1.31) P = 0.11 | 0.95 (0.85, 1.07) P = 0.14 |
  P for Log-likelihood ratio test | 0.29 | < 0.01 | 0.12 | 0.10 |