Well-defined search strategies can provide efficient and effective tools to help addressing specific research questions in the field of evidence-based prevention in occupational health. The planning of a preventive intervention is a fundamental process for the evaluation of the effectiveness of the intervention. The first step is to explore the scientific literature to retrieve all the relevant information. Developing a well-formulated research question is one of the challenging tasks an occupational health professional encounters when planning a public health intervention.
The detailed specification of the question will guide many aspects of the research including the formulation of the search strategy. The structure of the search strategy should be based on a clearly defined research question. The World Health Organisation suggests the PICO model to help defining the question. This acronym stands for Population (P), Intervention (I), Comparison (C), and Outcome (O). You cannot simply use the PICO terms to search in PubMed – the free search engine maintained by the US National Library of Medicine. You have to translate them into search terms. There are two types of search terms: the Medical Subject Headings (MeSH) terms and the ‘free text words’ (ie. non-MeSH terms). First, you have to define the MeSH terms from the PubMed thesaurus to produce highly specific searches. Then, it is recommended to include ‘free-text words’ considering that these search strategies are usually more sensitive than those containing MeSH terms only. When using non-MeSH terms, it is important to check for synonyms of the selected non-MeSH terms (eg. tennis elbow and epicondylitis), taking into account differences between British and American spelling and vocabulary.
In addition, you can take advantage of ready-to-use search filters for prompt identification of pertinent literature available in PubMed.