Table 2.
Parameter estimates using the Generalized Estimating Equations (GEE) model (imputed) (N = 244).
| Parameter | B | Std. error | 95% Wald confidence interval | Hypothesis test | |||
|---|---|---|---|---|---|---|---|
| Lower | Upper | Wald chi-square | df | Sig. | |||
| (Intercept) | 1.990 | .5912 | .831 | 3.149 | 11.326 | 1 | .001 |
| Years diagnosed | |||||||
| >20 years | .467 | .2467 | −.016 | .951 | 3.590 | 1 | .058 |
| 16–20 years | .319 | .2447 | −.161 | .798 | 1.697 | 1 | .193 |
| 11–15 years | .366 | .2301 | −.085 | .817 | 2.528 | 1 | .112 |
| 6–10 years | .292 | .2186 | −.137 | .720 | 1.780 | 1 | .182 |
| 1–5 years | 0a | — | — | — | — | — | — |
| Employment status | |||||||
| No | −.118 | .1402 | −.393 | .157 | .707 | 1 | .401 |
| Yes | 0a | — | — | — | — | — | — |
| Race | |||||||
| Indian | −.116 | .1250 | −.361 | .129 | .865 | 1 | .352 |
| Chinese | −.201 | .1122 | −.421 | .019 | 3.218 | 1 | .073 |
| Malay | 0a | — | — | — | — | — | — |
| Marital status | |||||||
| Widower | .163 | .3932 | −.607 | .934 | .173 | 1 | .678 |
| Divorced | .274 | .2920 | −.299 | .846 | .878 | 1 | .349 |
| Married | .136 | .2674 | −.388 | .660 | .259 | 1 | .611 |
| Single | 0a | — | — | — | — | — | — |
| Gender | |||||||
| Female | .047 | .985 | −.147 | .240 | .223 | 1 | .637 |
| Male | 0a | — | — | — | — | — | — |
| Time of HbA1c level | |||||||
| 7–12 months after sitagliptin | −.562 | .0941 | −.746 | −.377 | 35.586 | 1 | .000 |
| 3–6 months after sitagliptin | −.831 | .0801 | −.988 | −.674 | 107.550 | 1 | .000 |
| Before initiation of sitagliptin (Baseline) | 0a | — | — | — | — | — | — |
| Number of antidiabetes | −.038 | .1301 | −.292 | .217 | .084 | 1 | .773 |
| Age | −.010 | .0065 | −.023 | .003 | 2.345 | 1 | .126 |
| Changes in regimen | |||||||
| During initiation of sitagliptin | .101 | .2169 | −.324 | .526 | .216 | 1 | .642 |
| After initiation of sitagliptin | .020 | .0981 | −.172 | .213 | .043 | 1 | .837 |
| No change | 0a | — | — | — | — | — | — |
| Initiation dose of sitagliptin | |||||||
| 100 mg | .057 | .3022 | −.536 | .649 | .035 | 1 | .852 |
| 50 mg | .273 | .2901 | −.295 | .842 | .887 | 1 | .346 |
| 25 mg | 0a | ||||||
| Medications prior to sitagliptin initiation | |||||||
| Others | .281 | .2851 | −.278 | .840 | .969 | 1 | .325 |
| Biguanide, sulphonylurea, and insulin | .384 | .3392 | −.281 | 1.049 | 1.281 | 1 | .258 |
| Sulphonylurea and insulin | .009 | .3411 | −.660 | .678 | .001 | 1 | .979 |
| Biguanide and insulin | .226 | .3094 | −.381 | .832 | .533 | 1 | .465 |
| Biguanide and sulphonylurea | .194 | .1855 | −.170 | .558 | 1.092 | 1 | .296 |
| Insulin alone | .140 | .4808 | −.802 | 1.083 | .085 | 1 | .770 |
| Sulphonylurea alone | .062 | .1920 | −.314 | .438 | .104 | 1 | .747 |
| Biguanide alone | 0a | ||||||
| Initiation of sitagliptin | |||||||
| Added to current regime | −.159 | .1385 | −.431 | .112 | 1.318 | 1 | .251 |
| Switched from current regime | 0a | ||||||
| Baseline HbA1c | .790 | .0407 | .711 | .870 | 377.159 | 1 | 000 |
| (Scale) | 1.114 | ||||||
Dependent variable: HbA1c.
aSet to zero because this parameter is redundant.