1 | Developing complex intervention | ||
 1.1 | Identifying evidence base by reviewing published literature and existing systematic reviews | i | Epidemiology of high blood pressure and its control |
ii | Evidence base on treatment adherence | ||
iii | Identified existing systematic reviews and trials of interventions delivered by mobile phone | ||
 1.2 | Identifying and developing appropriate theory | i | Literature review and meeting with stakeholders and experts to decide on theory, behaviour change techniques, and intervention strategies |
ii | Qualitative studies with stakeholder groups to refine content and test delivery system | ||
 1.3 | Modelling process and outcomes | i | Used causal modelling approach to link determinants of behaviour to behaviours and subsequent health outcomes |
2 | Assessing feasibility and piloting methods | ||
 2.1 | Testing procedures for acceptability, compliance, and intervention delivery | i. | Tested components for feasibility and acceptability |
ii. | Service tested full intervention over 8-week period | ||
 2.2 | Estimating recruitment and retention | i. | Recruitment from general outpatient department of a large, single primary care facility |
ii. | Review of literature to determine best practice for ongoing retention of trial participants | ||
 2.3 | Determining sample size | i. | Data from observational studies used to calculate sample size |
3 | Evaluating complex intervention | ||
 3.1 | Assessing effectiveness | i. | Set up a large pilot RCT (South African National Clinical Trials Register DOH-27-1212-386; 28/12/2012; Pan Africa Trial Register PACTR201411000724141; 14/12/2013); ClinicalTrials.gov NCT02019823; 24/12/2013). Primary outcome change in mean systolic blood pressure at 1 year, data on secondary outcomes along hypothesised casual pathway also collected. Usual care group get infrequent non-health related SMS text messages, intervention groups get regular SMS text messages designed to support treatment adherence |
 3.2 | Understanding change processes | i. | Intervention fidelity assessed using message delivery logs and logs of participant contact |
ii. | In final phase of the trial qualitative study of participants, health care workers, and service providers to explore how the intervention might work (necessary pre-requisites), could be optimised, contextual factors, specific key ingredients which could be included in future interventions | ||
 3.3 | Cost-effectiveness | i. | Data on costs of developing, testing, and delivering intervention as well as health service costs collected and analyses in process |
4 | Implementation and beyond | ||
 4.1 | Dissemination | i. | Peer review publications, conference presentations, public engagement activities, making available tools used to develop and deliver intervention |
 4.2 | Surveillance, monitoring, and long-term outcomes | i. | Consent to access routinely collected health data. If intervention shown to be effective then process and outcome data could inform additional pragmatic trials. |