Maddison 2014.

Study characteristics
Methods	Study design: single‐blind multicentre RCT (2 sites) Country: New Zealand Dates participants recruited: 2010 to 2012 Maximum follow‐up: 24 weeks
Participants	Inclusion criteria: aged 18 years or more, with a diagnosis of IHD, defined as angina, myocardial infarction, revascularisation, including angioplasty, stent or coronary artery bypass graft within the previous 3 to 24 months. All participants were clinically stable as outpatients, able to perform exercise, able to understand and write English, and had access to the Internet (e.g. at home, work, library or through friends or relatives). Exclusion criteria: participants were excluded if they had been admitted to hospital with heart disease within the previous 6 weeks; had terminal cancer, or had significant exercise limitations other than IHD N randomised: total: 171; intervention: 85; comparator: 86 Diagnosis (% of participants): IHD: 100% MI: 74% Angina: 50% Age (mean ±SD): total: 60.2 ± 9.3; intervention: 61.4 ± 8.9; comparator: 59.0 ± 9.5 Percentage male: total: 81%; intervention: 81%; comparator: 81% Ethnicity: NZ Maori: total: 8%; intervention: 7%; comparator: 8% Pacific: total: 6%; intervention: 6%; comparator: 6% Asian: total: 10%; intervention: 9%; comparator: 10% NZ European/other: total: 76%; intervention: 78%; comparator: 76%
Interventions	Intervention: the HEART programme is a personalised, automated package of text messages via mobile phones aimed at increasing exercise behaviour over 24 weeks. Participants received six messages per week for the first 12 weeks, five messages per week for 6 weeks, and then four messages per week for the remaining 6 weeks. Components: exercise Setting: home Exercise programme modality: moderate to vigorous aerobic‐based exercise (e.g. walking and household chores) Length of session: minimum of 30 minutes Frequency: at least 5 days/week. Intensity: NR Resistance training included? No Total duration: 24 weeks Co‐interventions: focus on altering the key mediators of behaviour change, including self‐efficacy, social support and motivation. Comparator: usual care, with encouragement to be physically active and attend a cardiac club. Co‐interventions: all participants were free to participate in any other CR service or support that they wished to use (e.g. participating in community‐based CR education sessions on modifying CVD risk factors and psychological support), as well as encouragement to be physically active.
Outcomes	HRQoL, costs
Source of funding	Health Research Council of New Zealand and the Heart Foundation. Dr Maddison was supported by a Heart Foundation Research Fellowship and a Health Research Council Sir Charles Hercus Research Fellowship.
Conflicts of interest	None declared
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"....were randomly allocated..... by means of a central computerized service. Randomization was conducted using the minimization method, stratifying by sex (male and female), ethnicity (Maori – indigenous – and non‐Maori), and exercise history"
Allocation concealment (selection bias)	Low risk	"Allocation concealment was maintained up to the point of randomization"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"This was a single‐blind trial, where outcome assessors were blinded to treatment allocation"
Incomplete outcome data (attrition bias) All outcomes	Low risk	Loss to follow‐up was well reported and was similar in both groups. 10/85 (12%) and 8/86 (9%) were lost to follow‐up from the intervention and control groups, respectively.
Selective reporting (reporting bias)	Low risk	All outcomes described in the methods section are reported in results.