Table 2.
Multivariate analysis by non-conditional logistic regression for the detection of culturable and unculturable microorganisms by periodontal health status and country
| Independent variables | Unadjusted OR (95% CI) | Adjusted OR (95% CI) | LR (p-value) BIC | |
|---|---|---|---|---|
| P. gingivalis | Country | |||
| Spain | 1.0 (Ref.) | 1.0 (Ref.) | ||
| Colombia | 3.22 (1.53–6.76) | 3.84 (1.38–10.74) | ||
| Groups | ||||
| Health/gingivitis | 1.0 (Ref.) | 1.0 (Ref.) |
LR (chi2) = 0.62 Unadjusted BIC = 203.28 Adjusted BIC = 208.23 Difference = − 4.95 |
|
| Stages I–II | 2.44 (1.08–5.47) | 2.71 (1.09–7.72) | ||
| Stages III–IV | 6.43 (2.43–16.9) | 7.68 (2.28–25.8) | ||
| T. forsythia | Groups | |||
| Health/gingivitis | 1.0 (Ref.) | 1.0 (Ref.) |
LR (chi2) = 0.35 Unadjusted BIC = 172.91 Adjusted BIC = 181.20 Difference =−8.29 |
|
| Stages I–II | 1.76 (0.74–2.86) | 1.73 (0.72–4.14) | ||
| Stages III–IV | 7.53 (2.07–27.4) | 7.01 (1.88–26) | ||
| T. denticola | Country | |||
| Spain | 1.0 (Ref.) | 1.0 (Ref.) | ||
| Colombia | 2.55 (1.24–5.23) | 2.33 (0.82–6.57) | ||
| Groups | ||||
| Health/gingivitis | 1.0 (Ref.) | 1.0 (Ref.) |
LR (chi2) = 0.35 Unadjusted BIC = 204.43 Adjusted BIC = 209.54 Difference =−8.29 |
|
| Stages I–II | 2.53 (1.17–5.46) | 2.36 (0.92–6.18) | ||
| Stages III–IV | 21.6 (7.27–77.45) | 19.5 (4.94–73.3) | ||
| E. nodatum | Groups | |||
| Health/gingivitis | 1.0 (Ref.) | 1.0 (Ref.) |
LR (chi2) = 0.35 Unadjusted BIC= 204.43 Adjusted BIC = 209.54 Difference =−5.11 |
|
| Stages I–II | 2.01 (0.81–5) | 2.01 (0.81–5) | ||
| Stages III–IV | 15.6 (4.49–67.3) | 17.4 (5.7–42.7) | ||
| D. oralis | Groups | |||
| Health/gingivitis | 1.0 (Ref.) | 1.0 (Ref.) |
LR (chi2) = 0.62 Unadjusted BIC = 241.59 Adjusted BIC = 252.88 Difference = -11.29 |
|
| Stages I–II | 1.54 (0.74–4.18) | 1.74 (0.68–4.4) | ||
| Stages III–IV | 5.99 (2.71 -13.23) | 7.61 (2.11–20.4) | ||
| F. alocis | Groups | |||
| Health/gingivitis | 1.0 (Ref.) | 1.0 (Ref.) |
LR (chi2) = 0.82 Unadjusted BIC = 231.33 Adjusted BIC = 246.01 Difference =−14.68 |
|
| Stages I–II | 1.74 (0.83–2.74) | 1.48 (0.83–2.74) | ||
| Stages III–IV | 10.9 (4.56–23.2) | 7.72 (2.00–28.9) | ||
| E. brachy | Groups | |||
| Health/gingivitis | 1.0 (Ref.) | 1.0 (Ref.) |
LR (chi2) = 0.31 Unadjusted BIC = 203.28 Adjusted BIC = 208.23 Difference =−4.95 |
|
| Stages I–II | 0.53 (0.25–1.11) | 0.56 (0.25–2.11) | ||
| Stages III–IV | 3.57 (1.40–9.11) | 5.38 (1.30–12.11) | ||
| E. saphenum | Country | |||
| Spain | 1.0 (Ref.) | 1.0 (Ref.) | ||
| Colombia | 2.18 (1.22–4.79) | 2.42 (1.22–4.79) | ||
| Groups | ||||
| Health/gingivitis | 1.0 (Ref.) | 1.0 (Ref.) |
LR (chi2) = 0.30 Unadjusted BIC = 227.50 Adjusted BIC = 235.49 Difference =−7.99 |
|
| Stages I–II | 1.43 (0.67–3.01) | 1.36 (0.64–2.89) | ||
| Stages III–IV | 4.85 (1.99–11.7) | 4.18 (1.69–10.3) | ||
Model adjusted for country, age, and smoking
OR odds ratio, 95% CI 95 % confidence interval, LR likelihood ratio test, BIC Bayesian information criterion
All models showed no differences in the likelihood ratio test. The unadjusted model should be reported for all models because they present a lower BIC22