Table 4 Association of calculus and plaque with socio-demographic characteristics (n = 365^a)

Increase in age per year ^b

1.060 (1.035–1.085), < 0.001

1.046 (1.011–1.082), 0.009

0.028 (0.006), < 0.001

0.018 (0.007), 0.008

Country of origin (ref. Syrians) ^b

0.610 (0.410–0.917), 0.018

0.856 (0.496–1.477), 0.576

− 0.350 (0.126), 0.006

−0.053 (0.123), 0.667

Gender (ref. Male) ^b

0.298 (0.182–0.487), < 0.001

0.471 (0.260–0.852), 0.013

−0.658 (0.151), < 0.001

− 0.332 (0.144), 0.021

Increase in education per year ^b

0.946 (0.904–0.991), 0.019

0.930 (0.872–0.992), 0.028

−0.031 (0.013), 0.018

− 0.032 (0.013), 0.019

Pseudo R-squared value, P-value

0.048, < 0.001

0.029, 0.002

Wald Chi-squared, P-value

42.02, < 0.001

15.70, 0.003

Hosmer-Lemeshow test: Estimate, P-value ^c

37.729, 0.944^d

40.382, 0.899^d

Lipsitz test: Estimate, P-value ^c

2.022, 0.991^d

9.787, 0.368^d