The table below is a glossary of topic-specific terms used in TAG's reviews. For methodological and statistical terminology used in systematic reviews, see the Cochrane Glossary of Terms by clicking here




A period of being quit, i.e. stopping the use of cigarettes or other tobacco products. May be defined in various ways; see also: point prevalence abstinence; prolonged abstinence;continuous/sustained abstinence

Biochemical verification

Also called 'biochemical validation' or 'biochemical confirmation':

A procedure for checking a tobacco user's report that he or she has not smoked or used tobacco.  It can be measured by testing levels of nicotine or cotinine or other chemicals in blood, urine, or saliva, or by measuring levels of carbon monoxide (CO) in exhaled breath or in blood. See: SRNT Subcommittee on Biochemical Verification. 'Biochemical verification of tobacco use and cessation'; Nicotine & Tobacco Research, 2002: 4 (2); 149-59


A pharmaceutical drug originally developed as an antidepressant, but now also licensed for smoking cessation; trade names Zyban, Wellbutrin (when prescribed as an antidepressant).

Carbon monoxide (CO)

A colourless, odourless highly poisonous gas found in tobacco smoke and in the lungs of people who have recently smoked, or (in smaller amounts) in people who have been exposed to tobacco smoke. May be used for biochemical verification of abstinence.


Also called 'quitting’. The goal of treatment to help people achieve abstinence from smoking or other tobacco use, also used to describe the process of changing the behaviour

Continuous abstinence

Also called 'sustained abstinence'; cf 'prolonged abstinence'

A measure of cessation often used in clinical trials involving avoidance of all tobacco use since the quit day until the time the assessment is made. The definition occasionally allows for lapses. This is the most rigorous measure of abstinence.

'Cold Turkey'

Quitting abruptly, and/or quitting without behavioural or pharmaceutical support


A very intense urge or desire [to smoke]. See: Shiffman et al 'Recommendations for the assessment of tobacco craving and withdrawal in smoking cessation trials' Nicotine & Tobacco Research 2004: 6(4): 599-614


A neurotransmitter in the brain which regulates mood, attention, pleasure, reward, motivation and movement


Also called 'treatment effect' or 'effect size': the difference in outcome between the experimental and control groups

Harm reduction

Strategies to reduce harm caused by continued tobacco/nicotine use, such as reducing the number of cigarettes smoked, or switching to different brands or products, e.g. potentially reduced exposure products (PREPs), smokeless tobacco.

Lapse/ slip

Terms sometimes used for a return to tobacco use after a period of abstinence. A lapse or slip might be defined as a puff or two on a cigarette. This may proceed to relapse, or abstinence may be regained. Some definitions of continuous, sustained or prolonged abstinence require complete abstinence but some allow for a limited number or duration of slips. People who lapse are very likely to relapse, but some treatments may have their effect by helping people recover from a lapse.


[neural nicotinic acetylcholine receptors]:  Areas in the brain which are thought to respond to nicotine, forming the basis of nicotine addiction by stimulating the overflow of dopamine


An alkaloid derived from tobacco, responsible for the psychoactive and addictive effects of smoking.

Nicotine Replacement Therapy (NRT)

A smoking cessation treatment in which nicotine from tobacco is replaced for a limited period by pharmaceutical nicotine. This reduces the craving and withdrawal experienced during the initial period of abstinence while users are learning to be tobacco-free The nicotine dose can be taken through the skin, using patches, by inhaling a spray, or by mouth using gum or lozenges.


Often used to describe the result being measured in trials that is of relevance to the review. For example smoking cessation is the outcome used in reviews of ways to help smokers quit. The exact outcome in terms of the definition of abstinence and the length of time that has elapsed since the quit attempt was made may vary from trial to trial


A treatment using pharmaceutical drugs, e.g. NRT, bupropion, varenicline

Point prevalence abstinence (PPA)

A measure of cessation based on behaviour at a particular point in time, or during a relatively brief specified period, e.g. 24 hours, 7 days. It may include a mixture of recent and long-term quitters. cf. prolonged abstinence, continuous abstinence

Prolonged abstinence

A measure of cessation which typically allows a 'grace period' following the quit date (usually of about two weeks), to allow for slips/lapses during the first few days when the effect of treatment may still be emerging. See: Hughes et al 'Measures of abstinence in clinical trials: issues and recommendations'; Nicotine & Tobacco Research, 2003: 5 (1); 13-25


A return to regular smoking after a period of abstinence

Second-hand smoke

Also called passive smoking or environmental tobacco smoke [ETS]. A mixture of smoke exhaled by smokers and smoke released from smouldering cigarettes, cigars, pipes, bidis, etc. The smoke mixture contains gases and particulates, including nicotine, carcinogens and toxins.


The belief that one will be able to change one's behaviour, e.g. to quit smoking

SPC [Summary of Product Characteristics]

Advice from the manufacturers of a drug, agreed with the relevant licensing authority, to enable health professionals to prescribe and use the treatment safely and effectively.


A gradual decrease in dose at the end of treatment, as an alternative to abruptly stopping treatment


The toxic chemicals found in cigarettes.  In solid form, it is the brown, tacky residue visible in a cigarette filter and deposited in the lungs of smokers.


A technique of dosing at low levels at the beginning of treatment, and gradually increasing to full dose over a few days, to allow the body to get used to the drug.  It is designed to limit side effects.


A variety of behavioural, affective, cognitive and physiological symptoms, usually transient, which occur after use of an addictive drug is reduced or stopped. See: Shiffman et al 'Recommendations for the assessment of tobacco craving and withdrawal in smoking cessation trials' Nicotine & Tobacco Research 2004: 6(4): 599-614