Structure of Search Strategies for Systematic Reviews: Line by Line versus Block by Block versus Single-Line

6 min readJun 6, 2021
Search Strategy for Systematic Review

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Over the past 18 years, I have had this discussion several times with information specialists, researchers, students, and colleagues. Some seem to be defending a single approach at the beginning of the conversation, but as we go forward, they change their minds.

Unsurprisingly, all three approaches of structuring the search strategies are useful at the right time and place. There is no advice in PRESS, PRISMA, MECIR, or PRISMA-S to push you to follow one of the approaches.

Since there is no best practice guide, many get confused about what structure to choose for each purpose. Before I start explaining and avoiding wasting your time, this post is not about structuring the search based on PICO families (PECO, PIPOH, PICOS, etc.).

Line by Line Search Strategy

Borrowed from computer programming, we put the single term in each line in this structure, and there is no guide on how much information you can put in each line. Since each line is concise — usually one term or one set of terms followed by field tags — the entirety of the structure becomes long, and you have to scroll from top to…




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