Describing Context


The context (the distinctive features of a trial's setting, participants, clinicians and other staff) in which a trial is done is clearly important when considering how applicable its results are to other contexts (see Intervention Design), or for that matter, routine care within the same context in which the trial was done.  To support interpretation of a trial's results, trialists should do all they can to describe the context of their trial (see Interpretation).

Despite its importance, there is little guidance about what should be reported about context and little work exploring how context might influence the results of a trial (1), or the feasibility of widespread implementation. NPT provides a consistent framework with which to describe context for these purposes. Because NPT focuses on collective action and processes, it can help you to discover what people actually, practically, do. How people do things is is a very important part of the trial's context.  For example, under NPT's Collective Action component, which looks at how work gets done, trialists may find that an important part of their trial's context is a particular element of the existing training offered to nurses working in primary care. In jurisdictions where this element of training is not provided, the intervention may not be successful without provision of additional training to primary care nurses prior to using the intervention.

It is important to note that some of this context-mapping could happen before the trial (as in the example above) but, other elements may only be possible after the trial has started. For example, Reflexive Monitoring requires that individuals have experience of the intervention, which clearly can only be assessed once the trial has started. They may use their experience of the intervention during initial pilot work to critically assess contextual issues and this, in turn, may shape further pilot work and the design of the intervention for the main trial.

Things to consider

  • Describing context is important if others are to make informed judgements about the applicability of your trial's results to their own situation.
  • Describing context is difficult; you may not be conscious of some elements of your own context. NPT will help you to ask questions about your context and to enhance your description
  • Do you already believe that your intervention depends on one or more aspects of the particular context in which the trial is being done? Readers of your trial report need to know this; NPT might help you structure how you describe your trial to readers.
  • If an element of your context is missing (e.g. easy access to a particular piece of equipment) does your trial become an aspirational trial, which would require major structural changes to a healthcare system to implement? Readers of your trial report need to know this.
  • Describing context is important if others are to make informed judgements about the applicability of your trial's results to their own  situation.


  1. Wells M, Williams B, Treweek S, Coyle J, Taylor J. Intervention description is not enough: evidence from an in-depth multiple case study on the untold role and impact of context in randomised controlled trials of seven complex interventions. Trials 2012, 13:95.
  2. Wells EM: Behind the scenes of randomised trials of complex interventions - insiders reveal the importance of context. PhD Thesis. University of Dundee; School of Nursing and Midwifery; 2007.