Table 1.

Clinical Parameters

Parameter	Base Case Value	Range Examined	Reference
Natural History
Incidence of precancer	0.008	0.002–0.02	12,15,16,18
Probability of spontaneous regression of precancerous lesion at 7 years	0.3	0.1–0.5	17
Probability of regression of precancer upon treatment and counseling	0.28	0.1–0.8	35
Probability of developing Stage I/II cancer from precancer	0.008	0.006–0.05	12,17,18,38
Probability of developing Stage III/IV cancer from undiagnosed Stage I/II cancer	0.5	0.25–0.75	Assumption
Treatment, Recurrence and Survival
Probability of occult neck disease found on neck dissection for Stage I/II treatment	0.25	0.06–0.46	21
5 year local control failure rate for Stage I/II disease	0.42**	0.3–0.5	22
5 year local control failure rate for Stage III/IV disease	0.67**	0.5–0.8	3,22,24
Probability of Stage I/II presenting with local cancer recurrence	0.18	0.1–0.3	23
5 year survival for Stage I/II	0.80**	0.6–0.9	3
5 year survival for Stage III/IV	0.46**	0.3–0.6	3
5 year survival for Stage I/II recurrence	0.46**	0.3–0.6	25
2 year survival for Stage III/IV recurrence	0.16**	0.05–0.25	25
Screening and Compliance
Sensitivity of oral exam	0.74	0.6–0.9	27
Specificity of oral exam	0.99	0.95–0.99	5,27
Probability of oral exam among healthy and precancer patients – No Screen	0.13	0.05–0.25	2
Probability of oral exam among healthy and precancer patients – Screen	0.5	0.1–0.9	Assumption
Probability of oral exam among patients with undiagnosed Stage I/II cancer	0.6	0.2–0.9	Assumption
Probability of oral exam among patients with undiagnosed Stage III/IV cancer	0.9	0.6–0.9	Assumption
Probability of compliance with biopsy – No Screen	0.67	0.39–1	5,8,9
Probability of compliance with biopsy – Screen	0.8	0.5–1	Assumption

All probabilities are based on a 1-year cycle unless otherwise noted

^**Yearly rates derived from probability using Declining Exponential Approximation of Life Expectancy (DEALE)