Patient, Clinician, Practice Design, and Treatment Predictors of HbA1cFrom Multilevel Regression Analyses
| Domain/Variable | Model Predicting HbA1c as Continuous Variable (n = 666) β (95% CI) | Model Predicting HbA1c >7% (Poor Control) (n = 666) OR (95% CI) |
|---|---|---|
| HbA1c = glycosylated hemoglobin; OR = odds ratio; CI = confidence interval; GED = general equivalency diploma. | ||
| Note. Results from 2 models presented. For the model predicting values of HbA1c as a continuous variable to regression coefficients represent either (1) the change in HbA1c associated with 1 unit change in the predictor variable (for continuous predictors) to or (2) the difference in HbA1c for the predictor variable compared with the reference group (for categorical predictors). In the continuous HbA1c model, if a CI that does not include 0, the regression coefficient is significant at P <.05. In the model predicting poor control; a OR that does not include 1.0 is significant at P <.05. | ||
| * Estimate significant at P <.05. | ||
| † Clinician characteristics and practice design features were entered one at a time after all patient characteristics and treatment are in the model. | ||
| Patient Characteristics | ||
| Age | −0.01 (−0.02 to 0.00) | 0.99 (0.98 to 1.00) |
| Ethnicity (white is reference group) | ||
| African American | 0.47 (0.12 to 0.82)* | 1.31 (0.77 to 2.23) |
| Hispanic | 0.55 (0.10 to 0.99)* | 1.25 (0.66 to 2.40) |
| Other | 0.74 (0.18 to 1.30)* | 4.33 (1.63 to 11.47)* |
| Sex, male | 0.18 (−0.06 to 0.42) | 1.26 (0.89 to 1.78) |
| Education (college graduate is reference group) | ||
| Not a high school graduate | −0.02 (−0.36 to 0.32) | 0.87 (0.53 to 1.41) |
| High school graduate or GED | −0.15 (−0.43 to 0.13) | 0.89 (0.60 to 1.32) |
| Duration of diabetes | −0.00 (−0.02 to 0.02) | 1.01 (0.99 to 1.03) |
| Provider characteristics† | ||
| Years in practice | −0.01 (−0.02 to 0.01) | 0.99 (0.98 to 1.01) |
| Sex, male | −0.15 (−0.43 to 0.13) | 0.71 (0.44 to 1.37) |
| No. of patients with diabetes seen in typical month | −0.00 (−0.00 to 0.00) | 1.00 (0.99 to 1.01) |
| Practice type (single specialty is reference group) | ||
| Academic setting | 0.61 (0.25 to 0.97)* | 2.90 (1.56 to 5.38)* |
| Solo practice | 0.40 (0.03 to 0.77)* | 1.88 (1.01 to 3.50)* |
| Multispecialty group | 0.39 (0.03 to 0.75)* | 1.59 (0.88 to 2.88) |
| Combination of settings | 0.21 (−0.16 to 0.58) | 1.27 (0.69 to 2.36) |
| Practice design features† | ||
| Flow sheets | −0.09 (−0.37 to 0.19) | 0.81 (0.50 to 1.30) |
| Electronic medical record | −0.22 (−0.49 to 0.05) | 0.75 (0.47 to 1.19) |
| Involvement of nurse-practitioners or physician’s assistants | −0.37 (−0.67 to −0.08)* | 0.67 (0.41 to 1.11) |
| Patient registries | 0.06 (−0.38 to 0.49) | 1.24 (0.57 to 2.70) |
| Dietician | 0.28 (−0.09 to 0.64) | 1.45 (0.77 to 2.70) |
| Diabetes educators | 0.05 (−0.29 to 039) | 0.88 (0.49 to 1.56) |
| Endocrinologists | −0.03 (−0.28 to 0.21) | 1.09 (0.71 to 1.67) |
| Treatment (diet only is reference group) | ||
| 1 oral medication | 0.48 (0.06 to 0.90)* | 1.48 (0.84 to 2.62) |
| ≥ 2 oral medications | 1.10 (0.68 to 1.51)* | 2.97 (1.68 to 5.24)* |
| ≥ 1 oral medication and insulin | 1.54 (1.03 to 2.04)* | 5.72 (2.74 to 11.93)* |
| Insulin | 1.62 (1.00 to 2.23)* | 5.06 (2.06 to 12.43)* |