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Overall trial status
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Plain English Summary

Background and study aims
It can be very difficult to quit smoking and there are many different methods to try and stop smoking. A recent study showed that providing support to reduce cigarettes and increase physical activity may reduce smoking, and induce more quit attempts and short-term abstinence. By also focusing on increasing healthy behaviours some smokers may want to reduce and ultimately quit altogether. There are recent national guidelines to help smokers who are not ready to quit but until a larger study provides evidence that reducing smoking and increasing physical activity is effective, such an approach will not feature in any future updated guidelines. The overall aim of the this study is to examine if supporting smokers (who do not want to quit immediately) to reduce smoking and increase physical activity results in a reduction in smoking and, most importantly, in more smokers deciding to quit, and remain abstinent for at least 12 months, compared to those receiving usual support.

Who can participate?
Adult smokers aged 18 and older who are wishing to reduce but not quit in the next month.

What does the study involve?
Suitable smokers recruited from primary health care are randomly allocated to one of two groups. Those in the first group receive usual advice on reducing smoking and where to get further support. Those in the second group receive up to 8 face to face or phone contacts with a health trainer for up to eight weeks with support to reduce smoking and increase physical activity as decided by the smoker. After completing an initial assessment, all participants are asked to complete various surveys and measures after three, and nine months. Only if participants report that they are no longer smoking at three and nine months will they be asked to attend a face to face meeting with a researcher, to confirm abstinence using expired air levels of carbon monoxide. Only if after nine months they are abstinent will they be followed up after 15 months.

What are the possible benefits and risks of participating?
Participants receive a shopping voucher for completing and returning the questionnaire booklet at baseline, 3 and 9 months. We are mostly interested in moderate exercise, if participants who report that they would like to try heavy exercise during the intervention with the health trainer will be advised to check first with their GP as heavy exercise may pose a health risk.

Where is the study run from?
1. Plymouth University (Lead Centre) (UK)
2. Oxford University (UK)
3. Nottingham University (UK)
4. St George’s University of London (UK)

When is the study starting and how long is it expected to run for?
May 2017 to December 2020

Who is funding the study?
NIHR Evaluation, Trials and Studies Co-ordinating Centre (NETSCC) (UK)

Who is the main contact?
Dr Helen Hancocks

Trial website

Contact information



Primary contact

Dr Helen Hancocks


Contact details

Peninsula Clinical Trials Unit
Plymouth University
ITTC Building 1
Plymouth Science Park
United Kingdom
+44 1752315252

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Trial of physical Activity assisted Reduction of Smoking (TARS): A multi-centred, parallel, two group, randomised controlled clinical trial, with internal pilot, to compare tailored support to reduce smoking and increase physical activity as an aid to smoking reduction with brief advice to reduce or quit smoking



Study hypothesis

The overall aim of the proposed research is to examine if supporting smokers (who do not want to quit immediately) to reduce smoking and increase physical activity results in a reduction in smoking and, most importantly, in more smokers deciding to quit, and remain abstinent for at least 12 months, compared to those receiving usual support.

Ethics approval

South West - Central Bristol Research Ethics Committee, 05/10/2017, ref: 17/SW/0223

Study design

Randomised; Interventional; Design type: Prevention, Process of Care, Education or Self-Management, Psychological & Behavioural, Complex Intervention, Physical

Primary study design


Secondary study design

Non randomised study

Trial setting


Trial type


Patient information sheet

No participant information sheet available


Specialty: Primary Care, Primary sub-specialty: Public Health; UKCRC code/ Disease: Respiratory/ Lung diseases due to external agents, Cancer/ Malignant neoplasms of respiratory and intrathoracic organs, Cardiovascular/ Other forms of heart disease, Reproductive Health and Childbirth/ Disorders related to length of gestation and fetal growth


During the intervention participants meet with a health trainer once a week for eight weeks. Meetings are a combination of face-to-face, at a convenient place for the participant, and telephone. The health trainer help participants to reduce the amount they smoke in a way that suits the individual participant. The health trainer also helps participants to do more physical activity or exercise, if they want to. This could include help in setting goals, access to exercise classes, and a free step counter. There is no set amount of physical activity in this study; participants can choose to do as little or as much as is comfortable for them. If participants decide to try any hard physical activity, they are advised to talk to their doctor. Hard physical activity can have risks. We aim to look mainly at moderate physical activity. If participants want further help from their local NHS Stop Smoking Service or GP the health trainer may be able to help with that. If a smoker wishes to quit at any time during theeight week intervention period, they are offered 6 weeks of additional behavioural and motivational support from the health trainer, as well as support to access services as part of usual care to stop smoking (as available at each location) if desired.

All participants are followed up at three and nine months. Only those reporting a quit attempt at 9 months will be followed up at 15 months.

Intervention type



Drug names

Primary outcome measure

Carbon monoxide (CO) verified prolonged abstinence over 6 months – Participants will be invited to have the carbon monoxide levels in their breath measured at 3 and 9 months, if they report a quit attempt upon completion of the 3 and 9 month questionnaire booklets.

Secondary outcome measures

1. Point prevalence CO verified abstinence at three, nine and 15 months post baseline - Only those reporting abstinence by mailed survey at 3 and 9 months will be contacted for CO verification. Only those abstinent at 9 months will be followed up at 15 months by mailed questionnaires and if abstinent by face-to-face assessment of expired CO.
2. Self-reported smoking and use of aids to reduce/quit smoking is assessed using self-reporting on the number of cigarettes smoked and type of nicotine product, i.e. pipes, cigars and roll your own as well as reporting the use of e-cigarettes and NRT (nicotine replacement therapy) products as part of the questionnaire booklets at baseline, 3, 9 and 15 months.
3. Physical activity is measured using self-reported seven-day physical activity questions at baseline, three and nine months A sub set of all participants in the TARS study will be invited to wear an accelerometer for a 7 day period during the study. The accelerometer, and instructions for use will be mailed to selected participants at the 3 month time point from CTU, along with the 3 month questionnaire booklet.
4. Self-reported height and weight is measured using Body Mass Index (BMI) questions that are part of the questionnaire booklet mailed to participants from CTU at baseline, three and nine months
5. Health related quality of life (EQ-5D-5L & SF-12) questions which are part of the questionnaire booklet at baseline, three and nine months
6. Health economic outcomes are measured using a Health service utilisation and costs, including smoking related costs questions which are part of the questionnaire booklet at baseline, three and nine months
7. Process measures - The following process measures are also assessed as part of the self-report questionnaire booklets issued to all participants by CTU at the baseline and three months:
7.1. Importance and confidence in smoking reduction and cessation
7.2. Importance and confidence in being physically active
7.3. Availability of support to reduce smoking and increase physical activity
7.4. Use of physical activity for smoking regulation
7.5. Planning to change smoking
7.6. Planning to change physical activity
7.7. Self-monitoring of smoking
7.8. Self-monitoring of physical activity
7.9. Urge & strength of urge to smoke

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Adult smokers wishing to reduce but not quit in the next month
2. ≥ 18 years
3. ≥ 10 cigarettes per day (for at least 1 year). Irrespective of use of other nicotine containing products, for example, e-cigarettes and/or NRT products.
4. Able to give informed consent

Participant type


Age group




Target number of participants

Planned Sample Size: 900; UK Sample Size: 900

Participant exclusion criteria

1. Unable to walk unaided for at least 15 minutes
2. Any illness or injury that might be exacerbated by moderate or vigorous Physical activity
3. Unable to engage in the intervention or trial procedures due to language or other reasons (eg, provide an unacceptable level of risk to the research team)

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Plymouth University (Lead Centre)
Peninsula Schools of Medicine and Dentistry ITTC Building 1 Plymouth Science Park
United Kingdom

Trial participating centre

Oxford University
Nuffield Department of Primary Care Health Sciences Radcliffe Observatory Quarter Woodstock Road
United Kingdom

Trial participating centre

Nottingham University
Faculty of Medicine & Health Sciences Clinical Sciences Building Nottingham City Hospital Hucknall Road
United Kingdom

Trial participating centre

St George’s University of London
Population Health Research Institute St George's University of London Cranmer Terrace
SW17 0RE
United Kingdom

Sponsor information


Plymouth Hospitals NHS Trust

Sponsor details

The Research Office
Plymouth Hospitals NHS Trust
Level 2
Bircham Park Offices
1 Roscoff Rise
United Kingdom

Sponsor type

Hospital/treatment centre



Funder type


Funder name

NIHR Evaluation, Trials and Studies Co-ordinating Centre (NETSCC)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

The research team will work with stakeholders at each site, and nationally, to help to interpret the results and the implications for policy and practice. Dissemination may involve presentation at meetings of relevant support groups or other lay audiences, as well as NHS strategy forum at local and national level.

There will be a standing item on the agenda for each Project Management Group meeting on the publication plan and establishing authorship rules. It is expected that the trial protocol will be submitted for publication no later than the end of the 4 month internal pilot phase of the study. Reports will comply with current CONSORT guidelines for publishing randomised trials. The study results will be submitted for publication in relevant international, high impact, peer reviewed journals. Names of key collaborators and groups who have contributed to the trial will be clearly stated in all publications. The study findings will be presented at regional, national and international meetings as appropriate. An invitation will be extended to the PPI group members to comment on the findings at a dissemination event, and work with other key stakeholders (ie, public health and lead professionals, commissioners of SSS and health promotion support) to maximise impact (eg, through policy changes such as revisions to NICE guidelines for smoking harm reduction).

IPD sharing statement:
The data sharing plans for the current study are unknown and will be made available at a later date.

Intention to publish date


Participant level data

To be made available at a later date

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes