1. Characteristics of included studies.
| Study | Country | Setting (in‐/outpatients) | N randomised | N completed | Intervention 1 | Intervention 2 | Control 1 | Control 2 |
| Anthonisen 1994 | CA & US | In | 5887 | Not reported | BH & PH‐NRT | NA | UC | NA |
| Brandt 1997 | DK | In | 56 | 45 | BH | NA | UC | NA |
| Chen 2014 | CN | Out | 85 | 80 | BH | NA | BH | NA |
| Christenhusz 2007 | NL | Out | 234 | 225 | BH & PH‐BUP | NA | BH | NA |
| Crowley 1995 | US | In & out | 53 | 36 | BH & PH‐NRT | NA | BH & PH‐NRT | BH & PH‐NRT |
| Gorecka 2003 | PL | Out | 70 | 69 | BH & PH‐BUP | NA | BH & PH‐NRT | NA |
| Hilberink 2011 | NL | Out | 697 | Not reported | BH | NA | UC | NA |
| Kotz 2009 | NL | Out | 296 | 248 | BH & PH‐NOR | NA | BH & PH‐NOR | UC |
| Lou 2013 | CN | Out | 3562 | 2607 | BH | NA | UC | NA |
| Pederson 1991 | CA | In | 74 | 64 | BH | NA | BH | NA |
| Sundblad 2008 | SE | Out | 478 | 391 | BH | NA | UC | NA |
| Tashkin 2001 | US | Out | 411 | 278 | BH & PH‐BUP | NA | BH | NA |
| Tashkin 2011 | US | Out | 504 | 499 | BH & PH‐VAR | NA | BH | NA |
| Tonnesen 2006 | DK | Out | 370 | 288 | BH & PH‐NRT | BH & PH‐NRT | BH | BH |
| Wagena 2005 | NL | Out | 255 | 220 | BH & PH‐BUP | BH & PH‐NOR | BH | NA |
| Wilson 2008 | IE | Out | 91 | 68 | BH & PH‐NRT | BH & PH‐NRT | UC | NA |
CA: Canada; CN: China; DK: Denmark; IE: Ireland; NL: Netherlands; PL: Poland; SE: Sweden; US: United States
BH: behavioural; BUP: bupropion; NA: not applicable; NOR: nortriptyline; NRT: nicotine replacement therapy; PH: pharmacological; UC: usual care; VAR: varenicline