Table 3 Proportional Hazards Model of Malignant Transformation for Related Factors(n = 148)¹

Age

<=45 years

1.00

1.00

> 45 years

1.42

(0.93,2.22)

0.1007

1.42

(0.90,2.31)

0.1184

OPMDs

Hyperkeratosis or epithelial hyperplasia

1.00

1.00

Verrucous hyperplasia

1.38

(0.81,2.44)

0.2304

1.23

(0.66,2.31)

0.5077

Epithelial dysplasia

1.56

(0.92,2.82)

0.0991

1.51

(0.86,2.73)

0.1493

Location

Buccal²

1.00

1.00

Tongue

2.31

(1.46,3.71)

< 0.001

2.41

(1.43,4.16)

0.0012

Other³

1.34

(0.62,2.50)

0.4103

1.37

(0.62,2.68)

0.4062

Smoking

No

1.00

1.00

Yes

0.77

(0.47,1.44)

0.3958

0.98

(0.48,2.31)

0.9556

Alcohol use

No

1.00

1.00

Yes

0.99

(0.65,1.58)

0.9809

1.10

(0.68,1.87)

0.7134

Areca quid use

No

1.00

1.00

Yes

0.53

(0.28,1.34)

0.1505

0.98

(0.36,2.97)

0.9682