Table 2.

Pittsburgh Predictor, a 4-factor lung cancer risk prediction model

Risk factor		Points
1. Duration of smoking, years	<30	−10
	30–39	0
	40–49	8
	≥50	14
2. Age, years [1]	younger	0
2. Age, years [1]	older	4
3. Smoking status [2]	current	0
3. Smoking status [2]	former	−3
4. Smoking intensity, cigarettes/day	<20	−4
	20–29	0
	30–39	2
	≥40	5

Older age defined as age ≥57, ≥59, ≥61, and ≥68 years for persons smoking <30, 30–39, 40–49, and ≥50 years, respectively.

The quit smoking category includes former smokers with current attained age at least one year greater than age quit.