Developing a Search Strategy
- Formulate your research question: write out your research thesis as completely as possible. If there are multiple objectives, write a statement for each one
- Break the question down into various concepts; do this for each research question you developed, above
- Identify synonyms: for each concept, list various synonyms
After considering your search questions and identifying keywords and synonyms, you have chosen databases that index the information that may provide the answers to your questions. Constructing a search strategy is dependent on the question, the terms, and the database. Databases vary by the type and number of records they contain, their dates of coverage, the formats of literature they consider, and their scope. Databases also vary in how they index and their use of controlled vocabulary, like subject headings or a thesaurus.
Keywords can be combined with subject headings or defined terms, for example, in order to increase the precision of the search. Many databases have help pages explaining their specific features; please contact a librarian with any question at all.
To combine terms, use of Boolean logic: using the connector terms AND, OR, & NOT to structure your search query.
- AND requires that both keywords appear in the same document;
- OR requires that one or the other keyword appears;
- NOT requires that the keword is absent.
Use parentheses ( ) to nest concepts together.
Truncation: search for multiple keywords with the same root by using a truncation symbol such as * or ? at the end of the root (ex: using handl* will find handle, handled, handler, handles, and handling). Check what the truncation symbol is for whichever database you are searching by checking the help pages
Phrase searching: For two or more words that are almost always next to each other, you can force most databases to search for them as a phrase by surrounding them with double quotation marks. For example, "blood sampling"
Subject heading searching: Subject headings, a system of controlled vocabulary used to classify information into specific categories, provide a very powerful way to locate focused, on-topic results. The articles in PubMed, for example, are classified using Medical Subject Headings, or MeSH.
Considering Reproducibility, EBM and SR
ILAR Roundtable on Science and Welfare in Laboratory Animal Use
Institute for Laboratory Animal Research
National Academies of Science, Engineering and Medicine;
Reproducibility Issues in Research with Animals and Animal Models
Transportation of Laboratory Animals
Design, Implementation, Monitoring and Sharing of Performance Standards
Gene Editing to Modify Animal Genomes for Research – Scientific and Ethical Considerations
OHAT Sytematic Review
National Toxicology Program (NTP)
Office of Health Assessment and Translation (OHAT)
Systematic reviews of preclinical animal studies
Marlies Leenaars, SYRCLE (Systematic Review Centre for Laboratory animal Experimentation)
Radboud University Medical Center, Nijmegen, The Netherlands
Cochrane Community Archive
Experimental Design Assistant - EDA
The Experimental Design Assistant (EDA) is an online tool to guide researchers through the design of their experiments, helping to ensure that they use the minimum number of animals consistent with their scientific objectives, methods to reduce subjective bias, and appropriate statistical analysis.
Cressey, D. Better design for animal studies:
Web tool aims to reduce flaws in animal studies.
Nature. 2016. 531(7592)128.
PubMed MeSH and searching examples
When searching PubMed it is helpful to use the Medical Subject Headings (MeSH) to find relevant articles. MeSH headings are assigned to each article within MEDLINE by its staff and are intended to be consistent across articles. This allows them to return more relevant and consistent groups of articles when searched.
"Animal Testing Alternatives"[MeSH]
"Animal Use Alternatives"[MeSH]
"Laboratory Animal Science"[MeSH]
MeSH terms can be combined to produce generalized searches for major topics in animal testing, including the health, welfare, and housing of animal subjects. Listed below are some sample searches for major issues of interest in your literature search.
Environmental Enrichment: "animals, laboratory "[MESH] AND enrichment[Text Word] AND "housing, animal"[MESH]
Laboratory Animal Welfare: "animal welfare"[MESH] AND "animals, laboratory "[MESH])
Transgenic Mice: "mice, transgenic"[MESH] AND ("animal welfare"[MESH] OR "Animal Testing Alternatives"[MESH])
Pain and/or Stress Prevention and Control: ("stress, physiological/prevention and control"[MESH] OR "pain/prevention and control"[MESH] OR "stress, physiological/veterinary"[MESH] OR "pain/veterinary"[MESH]) AND "animal welfare"[MESH] AND ("animals, laboratory"[MESH] OR "research design"[MESH])
Suggested MeSH for: ReplacementTo exclude animals and humans:
your topic/objective NOT ("Animals"[Mesh] OR "Humans"[Mesh])
your topic/objective AND (("Models, Theoretical"[Mesh] NOT "Disease Models, Animal"[Mesh]) OR "Computer Simulation"[Mesh] OR "Cadaver"[Mesh] OR "Culture Techniques"[Mesh] OR "Cells, Cultured"[Mesh] OR "In Vitro "[Publication Type])
To exclude mammals:
your topic/objective AND "Animals" [Mesh] NOT "Mammals"[Mesh]
Suggested MeSH for: RefinementTo minimize pain:
your animal type and/or procedure AND ("Central Nervous System Depressants"[Mesh] OR "Sensory System Agents"[Mesh] OR "Anesthesia and Analgesia"[Mesh])
To minimize complications:
your animal type and/or procedure AND ("Intraoperative Complications"[Mesh] OR "Postoperative Complications"[Mesh] OR "Perioperative Care"[Mesh])
To improve animal welfare:
your animal type AND "Animal Welfare"[Mesh]