Where to search
Where to search depends on what kind of information you need. Are you looking for background information? Do you have a specific research question?
TYPES OF DATABASES (OVERVIEW)
If you have a specific research question you may need to search for scholarly literature via a citation database.
What is a citation database? A citation database is an online collection of referenced articles, books, and other materials. Depending on your topic, you may need to search in interdisciplinary and/or subject-specific databases.
Below are examples of citation databases. There is also a "cheat sheet" for a quick overview of some of the popular databases you will use for literature searching.
A comprehensive guide to searching and databases is RefHunter - Manual zur Literaturrecherche in Fachdatenbanken (pdf, German).
PubMed
What is it?
PubMed is the free interface for searching MEDLINE records. MEDLINE is the largest database of biomedical literature. PubMed also contains other resources and tools.
Scope/content
PubMed contains more than 30 million citations from the biomedical, life sciences literature.
Features
You can access other resources such as PubMed Central, NCBI Bookshelf, and search tools such as the MeSH database to find subject headings for your literature search. You can create an account to save references, search strategies, create search alerts, etc.
Search techniques
You can conduct a basic or an advanced search. The basic search is useful to explore a topic. PubMed's advanced search builder is helpful for systematic searches (when you have identified your research question and key concepts).
| Technique |
Explanation |
|---|---|
| Truncation * | Truncate at the end of the word: Child* finds child, children, Note: word must have more than 3 characters |
| Phrase Search | Use quotes to find exact phrases "lung damage" Note: can truncate within a phrase "lung damage*" |
| Field Search | Field tags to search parts of a record "lung damage*"[tiab] (searches in the title and abstract) |
| MeSH Search | Use MeSH terms for topic searches "Lung Injury"[Mesh] |
| Boolean Operators |
AND, OR, NOT |
Tutorials and handouts for PubMed
CINAHL
What is it?
CINAHL stands for the Cumulative Index of Nursing and Allied Health Literature. It is a database via the EBSCOhost platform.
Scope/content
Scope coverage in nursing, biomedicine, health sciences, alternative/complementary medicine, consumer health, etc. Other resources include health care books, nursing dissertations, selected conference proceedings, book chapters, and standards of practice materials.
Features
Access to evidence-based summaries of diseases, treatment options, etc. Nursing staff members can obtain continuing education units from the modules available. Basic and advanced search options are available. You can create an account to save your searches and references. Export search results from CINAHL to citation management tools.
Search techniques
| Technique | Explanation |
|---|---|
| Truncation * | arthroplast* finds arthroplasty, arthroplasties, arthroplastic, arthroplastics |
| Wildcard ? | wom?n finds women and woman |
| CINAHL Search | Topic search |
| Phrase Search | Place free text words in quotes to search in a phrase: "lung damage" |
| Field Search | Search in title and abstract: TI AB |
| Proximity Search | Proximity search is possible: N means near W means within |
| Boolean Operators | AND, OR, NOT |
Tutorial and handouts for CINAHL
MEDLINE via Ovid
What is it?
Ovid MEDLINE® is produced by the U.S. National Library of Medicine (NLM). Ovid is the searching platform for MEDLINE, the largest biomedical database.
Scope/content
The database contains more than 23 million references. It covers topics such as biomedicine, allied health, veterinary sciences, biological and physical sciences, humanities, and information science dating back to 1946.
Features
Basic and advanced search modes available. Other search features citation search, similar articles. For topic searches, you can access the MeSH database to identify subject headings.
Search techniques
| Technique |
Explanation |
|---|---|
| Truncation: *, $ | Unlimited truncation: Child* finds child, child's, children, children Limited truncation (set a number after the truncation symbol): |
| Wildcards: ?, # |
? cover zero to one character, for example, p?ediatric finds pediatric, paediatric # covers one mandatory character, for example, random#ed finds randomized, randomised |
| Field Search | Search free text terms in a field of a records Examples: .ti,ab,kw. (searches in the title, abstract, author keywords fields) |
| MeSH Search | Searches based on content rather than free text words MeSH terms are in a hierarchy, you can explode (exp) MeSH to search narrower MeSH terms exp Diabetes Mellitus/ |
| Proximity Search | ADJ, ADJN (N=number of words within 2 terms) adj finds terms in a specific order, for example, brain adj tumor* finds brain tumor, brain tumors adjn find terms in either order within a certain number of words adj3 finds for example brain adj3 tumor* finds brain tumors, tumors in the brain |
| Boolean Operators |
AND, OR, NOT |
Tutorial and handouts for MEDLINE via Ovid
Scopus
What is it?
Scopus is a license-based abstract and citation database by Elsevier.
Scope/content
It comprises over 77.8 million records in the fields of science, technology, medicine, social science, arts, and humanities from 1788 until today.
Features
It provides analytical tools to create citation overviews, view author and affiliation profiles, citation scores, and examine article and journal metrics. You can conduct a basic and advanced search. In the advanced search mode, you can search in various search fields and use advanced searching techniques.
Search techniques
| Technique | Explanation |
|---|---|
| Truncation / Wildcards: ?, * |
* represents any number of characters, even 0. It can be at the beginning or the ending of a term: comput* returns computer, computers, computerize and computerization *tocopherol finds α-tocopherol, γ-tocopherol , δ-tocopherol, tocopherol ? represents any single character: wom?n retrieves both woman and women |
| Field Search/Field Codes |
TITLE-ABS-KEY: terms are searched in title, abstract and author keywords |
| Proximity Operators | Proximity operators find words near/within a specified distance of each other. W/n for example, spine W/2 finds spine fractures, fractures of the spine PRE/n finds in a specific order, for example, posttraumatic PRE/2 disorder* finds posttraumatic disorder, postraumatic stress disorders |
| Exact Phrase: { } |
Put a phrase in curly brackets to find an exact match: {lung damage} |
| Loose Phrase: " " |
"lung damage" is search as (lung AND damage) in the search fields you are searching |
| Boolean Operators |
AND, OR, NOT |
Embase
What is it?
Excerpta Medica Database, known as EMBASE, is a biomedical and pharmacological database. You can access this database via Ovid or Elsevier provider. This guide refers to the Elsevier provider version.
Scope/Content
This database contains 30 million records including articles with strong coverage of drug and pharmaceutical research, pharmacology, and toxicology.
Features
The PV Wizard search tool is helpful for drug and pharmaceutical searches. Basic, PICO, and advanced search modes are available. Access the Emtree Thesaurus to find subject headings for topic searches.
Search techniques
| Technique |
Explanation |
|---|---|
| Truncation: * | therap* finds therapy, therapies, therapeutics |
| Wildcards: ?, * |
? replaces exactly 1 character: wom?n finds women, woman * replaces any number of characters and can be set at the beginning, within or at the end of a term: sul*r finds sulphur or sulfur |
| Field Search | :ti,ab,kw for title, abstract and author keywords. :dn for device trade name :tn for drug trade name |
| Emtree Search | Search by topic/subject headings: 'diabetes mellitus'/exp |
| Proximity Operators |
NEAR/n, NEXT/n (n represents the distance between terms, select from 0-99) NEAR/n searches in either order |
| Phrase Search |
"cancer therap*" finds cancer therapy, cancer therapies, cancer therapeutics, Note: you can truncate in a phrase search |
| Boolean Operators |
AND, OR, NOT |
Tutorial and handouts for Embase
Dimensions
What is it?
Dimensions is a license based platform for linked and enriched research data. A free version is available too.
Scope / content
It comprises records in the fields of medicine, life science and health science but also social sciences and other research area: Publications, clinical trials, grants, policy papers, patents and datasets.
The data is gathered from Crossref, PubMed, Europe PubMed Central, arXiv and from direct contacts with more than 130 publishers.
Stand 6.5.2021, © dimensions.ai
Features
- Linked and enriched data
Dimensions links different data to each other. With a single search it displays publications, grants, data sets, clinical trials, patents, and policy documents at one glance.
- Analysis of abstracts
Dimensions analyzes abstracts and suggests similar articles or search concepts. The latter can easily be added to a search string.
- Metrics
Dimensions Analytics offers metrics: How is a publication or a researcher's work perceived within the scientific community. Results are displayed in different visual ways.
Search techniques
| Technique |
Explanation |
|---|---|
| Boolean Operators |
AND, OR, NOT |
| Truncation: * |
* finds every ending of a word: therap* finds therapy, therapies, therapeutic etc. |
| Wildcards: ? |
? replaces exactly 1 character. Cannot be used inside of quotes: wom?n finds woman and women |
| Proximity Search: ~n |
Finds words in a distance of n from each other: ambient noise ~4 |
Tutorials and handouts for Dimensions
GREY LITERATURE (OVERVIEW)
Grey Literature is literature that is not published in the traditional sense such as clinical trials data, conference abstracts and proceedings, poster presentations, technical reports, government reports, datasets, thesis/dissertations, newsletters, lab notes, registries. It is important to include grey literature in your review in order to broaden its scope, reduce publication bias, and include emerging research.
We are often asked what database to search for grey literature. The truth is that there isn't just one and it depends on the topic. Consider your topic and its stakeholders. Checking the publications written by organizations and associations relevant to your topic is a good way to start.
Here are some resources for grey literature searching:
Grey Literature Search Guide from the University of Toronto Libraries
From the University of Toronto Libraries' Systematic Reviews in the Sciences & Health Sciences Guide.
Grey Matters: A Practical Tool for Searching Health-Related Grey Literature
CADTH's Directory of grey literature producers, with a focus on health technology assessment and drug resources.
GreyNet (former OpenGrey)
Information on Grey Literature in Europe and access to 700.000 bibliographical references of grey literature (paper) produced in Europe and allows you to export records and locate the documents.
Clinical trials registries
ClinicalTrials.gov
ClinicalTrials.gov is a registry and results database of publicly and privately supported clinical studies of human participants conducted around the world.
European Union Clinical Trials Register
The EU Clinical Trials Register contains information on interventional clinical trials on medicines conducted in the European Union (EU).
ISRCTN registry
The ISRCTN registry is a primary clinical trial registry recognised by WHO and ICMJE that accepts all clinical research studies (whether proposed, ongoing or completed), providing content validation and curation and the unique identification number necessary for publication.
WHO International Clinical Trials Registry Platform (ICTRP)
The main aim of the WHO ICTRP is to facilitate the prospective registration of the WHO Trial Registration Data Set on all clinical trials, and the public accessibility of that information.
Conference proceedings
Conference Proceedings Citation Index (part of Web of Science Core Collection)
Other databases such as Embase and PsycINFO include conference proceedings and papers. You can also search individual conference proceedings to locate relevant papers.
Drugs and medical devices
CADTH (Canadian Agency for Drugs and Technologies in Health)
CADTH is a Canadian independent, not-for-profit organization responsible for providing health care decision-makers with objective evidence.
SuRe Info
Summarized Research Information Retrieval for health technology assessment.
European Medicines Agency
The European Medicines Agency (EMA) is a decentralised agency of the European Union (EU), located in London. It began operating in 1995. The Agency is responsible for the scientific evaluation, supervision, and safety monitoring of medicines in the EU.
Devices@FDA
Devices@FDA is a catalog of cleared and approved medical device information from the United States Food and Drug Administration (FDA). It includes links to the device summary information, manufacturer, approval date, user instructions, and other consumer information.
Drugs@FDA
Information about FDA-approved brand name and generic prescription and over-the-counter human drugs and biological therapeutic products. Drugs@FDA includes most of the drug products approved since 1939.
Google Scholar
Researchers may decide to search Google Scholar for studies but may sometimes limit to a certain number of results such as the first 100 or 200.
Google Scholar searches may retrieve grey literature not indexed in academic databases. Keep in mind that Google Scholar is a search engine not a bibliographic database.
Google Scholar has an “Advanced Search” which can help focus on the vast number of results. Click on the menu icon in the top left corner to access.