Table 4 Recommendations compared to the Russell standard

Self-report

Prolonged abstinence

Over the whole follow-up period

Prolonged abstinence

6 or/and 12 months

Prolonged abstinence

6 or/and 12 months

Point prevalence abstinence

7 days^a

Point prevalence abstinence

7 days^a

Continuous abstinence

6 months^a

Number of cigarettes smoked

7 days^a

Number of cigarettes smoked

7 days^a

Grace period

Undefined

Undefined

Two weeks

Biochemical validation

Carbon monoxide

(9 p.p.m. in) expired air

Carbon monoxide

expired air

Cotinine^b

saliva^a

Cotinine^b

(15 ng/ml in) saliva^a

Follow-up

6 or/and 12 months

6 or/and 12 months

6 or/and 12 months