Fast‐acting nicotine replacement therapy showed no clear difference in smoking cessation compared with nicotine patch (high certainty).
Preloading nicotine replacement therapy (NRT) probably leads to higher smoking cessation compared with standard‐use NRT (moderate certainty).
Nicotine replacement therapy may leads to higher biochemically validated smoking cessation at the latest point in… compared with control (low certainty).
Bupropion plus nicotine replacement therapy (NRT) showed no clear difference in smoking cessation (at least six months of compared with NRT alone (low certainty).
Combination leads to higher smoking cessation compared with single‐form nicotine replacement therapy (high certainty).
Longer showed no clear difference in smoking cessation ‐ 6 weeks versus 2 weeks compared with shorter duration of combination nicotine replacement therapy (low certainty).
It is very uncertain whether longer changes smoking cessation ‐ 16 weeks versus 8 weeks compared with shorter duration of combination nicotine replacement therapy (very low certainty).
Higher‐dose showed no clear difference in smoking cessation ‐ 42/44 mg versus 21/22 mg (24‐hour patches) compared with lower‐dose nicotine patch (moderate certainty).
The intervention leads to higher smoking cessation at 6+ months (high certainty).
It is very uncertain whether the intervention changes smoking cessation ‐ gum versus inhaler (very low certainty).
It is very uncertain whether the intervention changes smoking cessation ‐ oral spray versus gum (very low certainty).
It is very uncertain whether the intervention changes smoking cessation ‐ oral spray versus inhaler (very low certainty).