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Systematic Review: Case Study - Starting - Developing a question

Case study - question

Cari is investigating different approaches to obesity. At a recent conference she heard about research showing that chocolate could be used to control cholesterol levels in people who are at risk of cardiometabolic disorders. While the results of the study sounded promising, Cari is concerned that more evidence would be needed to support changes in practice.


After talking to the conference presenter to learn more, Cari does some background reading about the topic. She makes a list of initial questions to investigate, including:


  • How much research has been done into this topic?

  • What compounds does cocoa contain?

  • Have any of these compounds been studied in relation to obesity or cholesterol?

  • What population groups were used in the existing research? (Are they all healthy, or has the research looked at those with obesity? Have studies focussed on humans or animals?)

  • What research links cocoa products to different health outcomes?

Cari starts by reading a couple of good reviews suggested by the conference presenter. Based on her findings, she decides to conduct a systematic review
into the topic to get a detailed picture of the available research.


Developing a question

Looking at the story above, we can see some concepts emerging. Let’s put them into a PICO table.




Developing a question

Cari’s initial question could therefore be:


In people at risk of cardiometabolic disorders whose weight is classified as obese (P), how effectively does chocolate (I) reduce cholesterol level (O)?

At this stage it is important for Cari to see what research is available through a preliminary background search on some of these concepts. This will help her to identify how much literature is available, as well as any areas where she might need to broaden or narrow her search question (e.g. to focus on specific types of chocolate or cholesterol). She might need to refine the question further while developing her search strategy.


Further example questions