PRECIS-2

Designing clinical trials is challenging. PRECIS – PRagmatic Explanatory Continuum Indicator Summary – is a clever acronym for a tool to help trialists designing clinical trials consider where they would like their trial to be on the pragmatic/explanatory continuum.

his is a 9-spoked ‘wheel’ with nine domains based on trial design decisions (i.e. Eligibility criteria - who is selected to participate in the trial? Recruitment - How are participants recruited into the trial? Setting - Where is the trial being done? Organisation – what expertise and resources are needed to deliver the intervention? Flexibility delivery – How should the intervention be delivered? Flexibility adherence – what measures are in place to make sure participants adhere to the intervention? Follow up – How closely are participants followed-up? Primary outcome – how relevant it is to participants? and Primary analysis – to what extent are all data included?).

The PRECIS-2 ‘wheel’ can visually represent how explanatory/pragmatic a trial is on the pragmatic to explanatory continuum. Trials that take an explanatory approach produce wheels nearer the hub; those with a pragmatic approach are closer to the rim.