Research Questions with PICO: A Universal Mnemonic

A well-formulated research question should incorporate the components of a ‘problem’, an ‘intervention’, a ‘control’, and an ‘outcome’—at least according to the PICO mnemonic. The utility of this format, however, has been said to be limited to clinical studies that pose ‘which’ questions demanding correlational study designs. In contrast, its suitability for descriptive approaches outside of clinical investigations has been doubted. This paper disagrees with the alleged limitations of PICO. Instead, it argues that the scheme can be used universally for every scientific endeavour in any discipline with all study designs. This argument draws from four abstract components common to every research, namely, a research object, a theory/method, a (null) hypothesis, and the goal of knowledge generation. Various examples of how highly heterogenous studies from different disciplines can be grounded in the single scheme of PICO are offered. The finding implies that PICO is indeed a universal technique that can be used for teaching academic writing in any discipline, beyond clinical settings, regardless of a preferred study design.