| Study | Reason for exclusion |
|---|---|
| Adelman 2009 | Study of nicotine nasal spray in adolescents. 12 weeks follow‐up |
| Allen 2005 | Short‐term study of effect of nicotine patch on weight change during early abstinence |
| Allen 2011 | Trial of NRT for reduction of agitation and aggression in smokers with schizophrenia |
| Aubin 2006 | Short‐term study of the effect of different types of nicotine patch on sleep and smoking urges |
| Batra 2005 | Trial of nicotine gum for smoking reduction in people not making a quit attempt. See Cochrane Review of harm reduction interventions, Lindson‐Hawley 2016 |
| Berlin 2011 | Trial of standard NRT dosing vs dose adaptation according to salivary cotinine |
| Bock 2010 | Trial of computer software quit programme, treatment group offered free NRT. Control group could also use NRT (unsubsidized) |
| Bolliger 2000a | Trial of nicotine inhaler for smoking reduction in people not making a quit attempt. See Cochrane Review of harm reduction interventions, Lindson‐Hawley 2016 |
| Bolliger 2007 | Pilot study, not powered to detect efficacy differences between gum, inhaler and mouth spray |
| Brantmark 1973a | Double‐blind gum/placebo only for 1st week of clinic, then both groups offered active gum during 6‐month follow‐up period |
| Caldwell 2016 | All arms received pharmacotherapy |
| Carpenter 2003 | Compared 2 methods of reducing smoking. Control group also offered NRT if a quit attempt planned |
| Carpenter 2011 | Measured effect of providing NRT samples on participants not initially motivated to quit. Participants were encouraged but not required to make a practice quit attempt. Intervention participants were provided with up to 2 boxes of nicotine lozenges |
| Chan 2010 | Measured effect of counselling + 2 weeks free NRT. No data on whether control group also using NRT; unclear if outcome due to counselling or free NRT |
| Chan 2011 | Measured effect of adherence counselling as opposed to effect of NRT itself |
| Chou 2004 | Only 3 months follow‐up |
| Christen 1984 | Only 15 weeks follow‐up |
| Cohen 1989a | Primarily a trial of training dentists. Included in Cochrane Review of training of health professionals (Carson 2012) |
| Cohen 1989b | Primarily a trial of training doctors. Included in Cochrane Review of training of health professionals (Carson 2012) |
| Croghan 2007 | Provides a short‐term comparison between nicotine patch, bupropion, and combination therapy. Initial failures randomized to retreatment so no long‐term control group |
| Cummings 2011 | Compared provision of free NRT, but participants able to use additional NRT as desired |
| Dey 1999 | Compared free and paid prescription for nicotine patch. Only 14 weeks follow‐up |
| Donny 2009 | Endpoint not cessation |
| Ebbert 2009 | Study of NRT for smokeless tobacco users |
| Ebbert 2010 | Study of mailed NRT for smokeless tobacco users |
| Elan Pharm 88‐02 | No long‐term follow‐up. Long‐term follow‐up for 1 site included as Hurt 1990 |
| Elan Pharm 90‐03 | No long‐term follow‐up. Long‐term follow‐up for 1 site included as Fiore 1994a |
| Etter 2004 | Trial of a choice of NRT products for smoking reduction in people not making a quit attempt. See Cochrane Review of harm reduction interventions, Lindson‐Hawley 2016 |
| Fagerström 1993 | Endpoint withdrawal symptoms, not cessation |
| Fagerström 1997 | Short‐term cross‐over trial of different types of NRT. For 2 weeks smokers could choose a method, for other 2 they were randomly assigned to one of gum, patch, spray, inhaler or tablet. Smoking reduction assessed |
| Fagerström 2000 | Short‐term cross‐over trial comparing 2 nicotine delivery devices |
| Ferguson 2012 | Study of offer of free NRT via NHS Quitline services. Control group had access to and used free NRT and other stop‐smoking medications at high levels; study conditions were very similar for both groups |
| Finland unpublished | Only 3‐month follow‐up. Comparison of patch and nasal spray (n = 51) versus nasal spray alone (n = 50). Sustained abstinence rates 18% in each group. Used in a sensitivity analysis of combination therapies |
| Foulds 1993 | Follow‐up less than 6 months |
| Garvey 2006 | Not enough information currently available (abstract only) |
| Glover 1992 | Follow‐up less than 6 months |
| Gross 1989 | Study of weight gain. Abstinence outcomes not reported |
| Guo 2006 | Only 3 months follow‐up |
| Hajek 1999 | Follow‐up less than 6 months |
| Hanson 2003 | Follow‐up only 10 weeks; primary outcomes were withdrawal, craving, safety and compliance among adolescents |
| Haustein 2003 | Trial of nicotine gum for smoking reduction in people not making a quit attempt. See Cochrane Review of harm reduction interventions, Lindson‐Hawley 2016 |
| Hoch 2006 | Not enough information currently available (abstract only) |
| Hotham 2006 | RCT of nicotine patch as adjunct to counselling for pregnant smokers. Only 20 people in each condition, with high withdrawal and low compliance. |
| Hughes 1989b | No long‐term follow‐up, primarily a trial of the effect of instructions |
| Hurt 1995 | Analysis of prior nicotine patch studies (to determine if recovering alcoholic smokers were more nicotine‐dependent than non‐alcoholics and whether the efficacy of nicotine patch therapy was comparable) |
| Hurt 2003 | All participants received nicotine patch |
| Jarvik 1984 | Reports subgroup analysis by level of nicotine dependence. See Schneider 1983a for main outcomes |
| Jibrail 2010 | Only 12 weeks follow‐up. Study of NRT for smoking abstinence and relationship between c‐reactive protein and depressed mood during nicotine abstinence |
| Kapur 2001 | Only 12 weeks follow‐up. Trial of nicotine patch in pregnant smokers. 30 participants |
| Korberly 1999 | Insufficient data in unpublished abstracts to include |
| Kozak 1995 | Open‐label study in which smokers with higher nicotine dependence scores were given higher patch doses |
| Kras 2010 | Study of NRT and hypericum perforatum extract. Only 10 weeks follow‐up |
| Krumpe 1989 | Only 10 weeks follow‐up |
| Krupski 2016 | All arms received pharmacotherapy |
| Kupecz 1996 | Participants were randomized by month of treatment to group therapy with nicotine patch (n = 21) or gum (n = 17) |
| Landfeldt 1998 | Only 12 weeks follow‐up reported in abstract |
| Leischow 1996b | Only 10 weeks follow‐up |
| Levin 1994 | Only 9 weeks follow‐up |
| Lin 1996 | Only 8 weeks follow‐up |
| Marsh 2005 | Only 3 months follow‐up, safety study comparing 4 mg lozenge to 4 mg gum |
| McCarthy 2006 | Only 3 months follow‐up, study of withdrawal symptoms |
| McRobbie 2010 | Short‐term cross‐over study assessing withdrawal symptoms and user satisfaction |
| Meier 1990 | Short‐term follow‐up. Compared dependence individualized to standard dose patch. |
| Merz 1993 | Only 3 months follow‐up |
| Miller 2009 | 1377 low‐income smokers with quitline and subsidized NRT. Participants informed what group they would be in when first invited to participate |
| Millie 1989 | Only 2 months follow‐up |
| Minneker 1989 | Only 9 weeks follow‐up |
| Molander 2000 | Cross‐over study with 2‐day smoke‐free periods |
| Mooney 2005 | All participants used nicotine gum |
| Mulligan 1990 | Only 6 weeks follow‐up |
| Nackaerts 2009 | Insufficient data in published abstract to include (longest follow‐up reported in abstract 1m); NRT delivered for maximum 7 days |
| NCT00000437 | 3‐month follow‐up only. Thank you to Barbara Mason for confirming |
| Okuyemi 2007 | Intervention combined nicotine gum and multiple sessions of motivational interviewing |
| Oncken 2009 | Study of short‐term effects of NRT in pregnant smokers |
| Piper 2016 | All arms received pharmacotherapy |
| Pomerleau 2003 | Compared extended treatment (18 weeks) to 10‐week treatment with nicotine patch. No follow‐up beyond 18 weeks |
| Rennard 2006 | Trial of nicotine inhaler for smoking reduction in people not making a quit attempt. See Cochrane Review of harm reduction interventions, Lindson‐Hawley 2016 |
| Rey 2009 | All study participants received nicotine nasal spray. Comparison between different types of instructional guidance for dosing |
| Rigotti 2009 | Assessed effectiveness of adding NRT to rimonabant which has not been licensed for smoking cessation and results may not be generalizable |
| Roddy 2006 | Only 13 weeks follow‐up. At this point there were no quitters in either the treatment or control group. There were particularly high losses to follow‐up (64% overall) and low compliance (median duration of patch use 1 week) |
| Rose 1990 | Only 3 weeks follow‐up |
| Rubinstein 2008 | Only 12 weeks follow‐up |
| Sachs 1995 | Only 6 weeks follow‐up |
| Schlam 2016 | All arms received pharmacotherapy |
| Schneider 2004 | Short‐term cross‐over study |
| Schneider 2008 | Outcome was craving and withdrawal, not abstinence |
| Schnoll 2015 | All arms received pharmacotherapy |
| Shahab 2011 | Short‐term cross‐over trial of withdrawal symptom relief |
| Shiffman 2000a | Compared 10 and 6 weeks of patch treatment without longer follow‐up. Main outcome was craving and withdrawal |
| Shiffman 2000b | Comparison between 24‐h and 16‐h patches. Assessment of craving and abstinence over 2 weeks |
| Shiffman 2002a | Only 10 weeks follow‐up |
| Shiffman 2002b | Not a randomized trial. Compared prescription and OTC patch in different populations using different methods |
| Shiffman 2006 | Only 6 weeks follow‐up. High‐dose (35 mg) patch |
| Stapleton 2011 | Only 12 weeks follow‐up |
| Sun 2009 | Only 3 months follow‐up |
| Sussman 2004 | Presents Project EX program for adolescent tobacco use cessation. Mentions trial of nicotine gum vs herbal gum but insufficient detail provided |
| Sutherland 1999 | Only 3 months follow‐up. Comparison of patch and nasal spray (n = 104) versus patch alone (n = 138) or nasal spray alone (n = 138). Used in a sensitivity analysis of combination therapies |
| Sutherland 2005 | Only 12 weeks follow‐up |
| Sutton 1987 | Control group received no treatment so effect of nicotine gum is confounded with the brief counselling |
| Sutton 1988 | Control group received no treatment so effect of nicotine gum is confounded with the behavioural support |
| Thorsteinsson 2001 | No long‐term follow‐up reported |
| Tsukahara 2010 | Follow‐up less than 6 months. Direct comparison of varenicline and nicotine patch for smoking cessation |
| Tundulawessa 2010 | Only 4 weeks follow‐up |
| Tzivoni 1998 | Follow‐up less than 6 months |
| Tønnesen 1996 | All study participants received nicotine nasal spray. Comparison between ad lib and fixed schedule dosing |
| Uyar 2005 | Unpublished, insufficient detail in abstract on nicotine patch dose, length of treatment, level of support |
| Velicer 2006 | Participants were sent nicotine patches if they were assessed as potentially ready to quit. They did not have to set a quit date |
| Vial 2002 | Treatment groups differed from control in amount of counselling as well as use of NRT |
| Vikhireva 2003 | Trial of free choice of NRT product vs assigned NRT product from the outcome; no control group |
| Warner 2005 | Goal of intervention was relief of stress and withdrawal postoperatively |
| Wennike 2003a | Trial of nicotine gum for smoking reduction in people not making a quit attempt. See Cochrane Review of harm reduction interventions, Lindson‐Hawley 2016 |
| Williams 2007 | Only short‐term outcomes reported in conference abstract. Trial terminated early when no benefit of higher dose detected in interim analysis |
| Wiseman 2005 | 2‐week cross‐over study |
| Working Group 1994 | Follow‐up less than 6 months |
h = hour; OTC = over the counter;