Table 3.
Mixed regression models evaluating study effects (exposure: INVEST versus SHIP (ref.), half-mouth with four sites, regression coefficients (B) or Odds Ratios (OR) listed in the last column) on periodontal variables adjusting for remaining covariates. Model predicted values according to study are given as mean (SE). Subjects were 55–81 years old.
| SHIP | INVEST | Study effect | |
|---|---|---|---|
| N-AL/N-PD | 1158/1285 | 670/688 | |
| Prevalence of subjects with, % | OR (95% CI) | ||
| AL≥4 mm | 96.1 (0.2) | 90.1 (0.2) | 0.4 (0.2; 0.8) ** |
| AL≥5 mm | 86.8 (0.1) | 74.6 (0.2) | 0.4 (0.3; 0.8) ** |
| AL≥6 mm | 69.5 (0.1) | 58.4 (0.2) | 0.6 (0.4; 1.0) * |
| Mean percentage of sites/subject with, % | B (95% CI) | ||
| AL≥4 mm | 52.2 (1.4) | 29.5 (2.2) | −22.7 (−29.1; −16.3) *** |
| AL≥5 mm | 35.7 (1.3) | 17.8 (2.1) | −18.0 (−24.0; −11.9) *** |
| AL≥6 mm | 23.4 (1.1) | 9.8 (1.8) | −13.6 (−18.9; −8.4) *** |
| Mean AL, mm | 4.0 (0.08) | 2.8 (0.12) | −1.2 (−1.5; −0.8) *** |
| Mean AL, mm # | 3.9 (0.08) | 2.8 (0.12) | −1.0 (−1.4; −0.7) *** |
| Prevalence of subjects with, % | OR (95% CI) | ||
| PD≥4 mm | 75.6 (0.1) | 70.5 (0.2) | 0.8 (0.5; 1.2) |
| PD≥5 mm | 53.1 (0.1) | 40.0 (0.2) | 0.6 (0.4; 0.9) * |
| PD≥6 mm | 34.3 (0.1) | 16.5 (0.2) | 0.4 (0.2; 0.7) ** |
| Mean percentage of sites/subject with, % | B (95% CI) | ||
| PD≥4 mm | 17.7 (0.8) | 11.6 (1.4) | −6.1 (−10.2; −2.1) ** |
| PD≥5 mm | 9.2 (0.6) | 5.8 (1.1) | −3.3 (−6.4; −0.2) * |
| PD≥6 mm | 4.8 (0.5) | 2.4 (0.8) | −2.4 (−4.7; −0.2) * |
| Mean PD, mm | 2.7 (0.04) | 2.4 (0.06) | −0.3 (−0.5; −0.2) *** |
| Mean PD, mm $ | 2.6 (0.04) | 2.4 (0.06) | −0.2 (−0.4; −0.05) * |
| CDC/AAP classification, % | OR (95% CI) | ||
| moderate/severe versus no or mild | 70.0 (0.1) | 62.3 (0.2) | 0.7 (0.4; 1.1) |
| severe versus no or mild | 67.1 (0.1) | 32.6 (0.2) | 0.2 (0.1; 0.5) *** |
p<0.05,
p<0.01,
p<0.001,
before calculation of mean values, periodontal site measurements were corrected using probe correction values (see Online Supplement).
Mixed linear (for mean and extent values) or logistic models (for prevalences and CDC/AAP classification) with ‘study’ as the exposure variable adjusting for age, gender, race/ethnicity, smoking status, pack years, education, diabetic status, BMI, last dental visit was within last 12 months, tooth brushing frequency, and use of interdental care devices.
N-AL, number of subjects in models where attachment loss (AL) was the dependent variable; N-PD, number of subjects in models where probing depth (PD) was the dependent variable.
For dichotomous periodontal variables (prevalence, CDC/AAP classification), adjusted predicted probabilities with standard errors (SE) for linear predictions are given. For continuous periodontal variables (mean, mean percentage of sites/subject) adjusted linear predictions with their standard errors (SE) are given.