Prognostic factors affecting the short-term efficacy of non-surgical treatment of chronic periodontitis: a multilevel modeling analysis

Table 7 The mixed-effects model

	Coefficient	Standard deviation	Variance component	Inspection value	P value
Fixed effect part
Intercept	2.45	0.41		6.02^a	0.000***
Site location	− 0.3	0.05		− 6.03^a	0.000***
Baseline PD	0.30	0.03		9.60^a	0.000***
Tooth type	− 0.39	0.04		− 8.82^a	0.000***
TM	− 0.32	0.04		− 7.34^a	0.000***
BI	− 0.20	0.03		− 7.17^a	0.000***
CAL	− 0.14	0.02		− 5.93^a	0.000***
Age	0.001	0.004		0.34^a	0.739
Gender	− 0.09	0.07		− 1.30^a	0.199
Smoking	− 0.35	0.08		− 4.36^a	0.000***
Compliance	− 0.21	0.07		− 3.14^a	0.003**
BMI	− 0.01	0.01		− 0.91^a	0.365
Percentage of baseline PD ≥ 5 mm	0.005	0.002		2.50^a	0.016**
OHA score	0.07	0.03		2.35^a	0.023**
Education	0.03	0.06		0.45^a	0.658
Random effect part
Intercept μ₀₀		0.14	0.02	611.03^b	0.047*
Intercept e₀₀₀		0.96	0.93	94.36^b	0.000***
BI		0.13	0.02	51.28^b	0.029**
TM		0.22	0.05	104.47^b	0.000***
CAL		0.10	0.01	64.87^b	0.001**
Baseline PD e₂₀		0.18	0.03	129.10^b	0.000***
− 2logL	7176.81			912.75^c	0.000***

BMI body mass index, PD probing depth, OHA oral health awareness, BI bleeding index, TM tooth mobility, CAL clinical attachment loss, − 2logL, − 2 times the log likelihood
***P < 0.001, **P < 0.01, *P < 0.05
^at value; ^bx² value; ^cx² value compared with the − 2logL goodness of fit of the null model

ISSN: 2047-783X