A framework is a structure that can help organise the theory that supports or comes from your research. Frameworks can be used both when planning an intervention or when describing the outcomes of an intervention. There are many different frameworks and it is important to thick carefully and critically about which framework will work best for your study. This section will provide information on when, how, and why to use some of the major frameworks that can be found in the adolescent health literature.

Theory of Change in the health sector is defined as “an outcomes- based approach which applies critical thinking to the design, implementation, and evaluation of initiatives and programmes intended to support change in their context”. It essentially answers the question “how” your intervention works to create change or impact in the short, medium and long term. As described in this “How to build a theory of change” guide, your theory of change should be:

• Credible – based on previous experience and insight from your different stakeholders or relevant research where appropriate.
• Achievable – you have the necessary resources to carry out the intervention
• Supported – your stakeholders will be involved in defining and agreeing your theory of change, which builds support for it
• Testable – a complete but not over-complicated description of your work and its outcomes, with prioritised outcomes for measurement and indicators to collect data against them.

An example of the theory of change model used for the DREAMS programme established by PEPFAR to prevent HIV amongst adolescent girls and young women can be found in this 2018 publication.

The development assistance framework defines the theory of change (ToC) as a method that explains how a given intervention, or set of interventions, are expected to lead to a specific development change, drawing on a causal analysis based on available evidence. To draw a linear line of causality between the intervention and the desired outcomes, researchers need to conduct a baseline study by measuring the concept to be changed, e.g. levels of HIV knowledge among young people or disease burden in adolescents that are about to enter clinical trials. The baseline measure is followed by socio-behavioural or clinical interventions over a defined period of time and then an end line assessment at the end. The fundamental point is that researchers gather sufficient evidence to prove that a particular intervention is bringing about the intended outcomes, and that such an intervention can be replicated in similar settings to achieve desired results.