Naughton 2014.

Methods	Study design: RCT Country: UK Recruitment: participants were recruited from 32 participating primary care practices opportunistically, through self‐referral or referred by a health professional. Study dates: 2009‐11
Participants	Baseline characteristics (n = 317) Mean age: 41.8 years (SD 13.0) Female: 52.7% (N = 167) High school or lower education: not stated First cigarette in 30 min: 67.9% (N = 215) White: 98.0% (311) Inclusion criteria: participants aged 18‐75 years and current smokers (≥ 1 cigarette/day and smoked within previous 7 days) who were willing to quit within 14 days of randomisation, recruited in primary care. Participants were self‐referred or referred by a health professional, able to read English and provide written informed consent, with a mobile phone and familiar with sending and receiving text messages Exclusion criteria: enrolled in another formal SC study or other cessation programme
Interventions	Control: 'usual care' consisting of routine 'level 2' SC advice delivered by SC adviser. This included a brief discussion about smoking habits and history, measurement of expired‐air CO, brief advice to quit, setting a QD within the next 14 days, options for pharmacotherapy, a prescription and arranging a follow‐up visit. Usually the opportunity for multiple follow‐up visits was offered Intervention: usual care as above, plus a tailored advice report and a 90‐day programme of tailored text messages generated by the iQuit system (number of messages sent each day varied from 0 to 2, mean/day over 90 days 1.2). The messages were designed to advise smokers on their quit attempt, provide information about the consequences of smoking and expectations for quitting, provide encouragement, boost self‐efficacy, maintain motivation to quit and remind smokers how to cope with difficult situations
Outcomes	Definition of abstinence: self‐reported continuous abstinence at 6‐month follow‐up
Funding source	National Institute for Health Research School for Primary Care Research. GP practice costs (NHS Service Support Costs) were provided by the Comprehensive Local Research Network. ATP was supported by the NIHR Biomedical Research Centre at Guy's and St Thomas's NHS Foundation Trust and King's College London.
Conflicts of interest	None declared
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomised by online programme
Allocation concealment (selection bias)	Low risk	Randomised by online programme once baseline data collected
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Outcomes collected via postal questionnaire, with the same amount of investigator contact between groups
Incomplete outcome data (attrition bias) All outcomes	Low risk	65/303 in control and 70/299 in intervention lost to follow‐up at 6 months. ITT analyses presented