What causes disease?
How you conceptualize your topic affects how you search for relevant information. All inquiries are partial and are shaped by ingrained assumptions and values. (Source).
Consider first the interaction of environmental factors (eg, pollution, outbreaks) and social factors (eg, smoking, drug use). But you may also wish to consider other aspects of your topic.
Think about the wider context of your topic. Do some preliminary exploration, both in the literature and in discussions with your instructors, advisors, and peers. What are the relevant scientific and policy circumstances?
Especially when researching for policy-related questions, determine whether you are looking for evidence to clarify a policy issue, options to address a problem, implementation considerations, or evaluation concerns. This will help refine your question and your search. (Source).
Is your topic researchable?
You may need to broaden or narrow the focus of your topic.
This may become more apparent as you search for and find information. It may prove difficult to find research on very narrow topics, or to cope with the vast literature on an unfocused, broad topic.
What is the scope of your search?
Literature searching often involves balancing finding all relevant citations (which means you may also find many non-relevant citations), with finding only relevant citations (which means you may miss some relevant citations).
The search scope, as well as the purpose and audience of your literature search, influences how you focus your search when using online databases, as well as when you decide you have "enough."
Remember that research is not a linear process; you may find yourself modifying your search terms as you explore your topic.
Which disciplines are concerned with your topic? Which aspect(s) of your topic - legal, political, environmental, behavioral etc. - is/are of interest?
Answering these questions will help you decide which databases to search for literature. Although PubMed may be the best place to start for most public health topics, you may miss key literature if you do not use other resources.
What to consider as you find articles and other documents:
Below are some examples of questions or lines of inquiry.
Considering what question a research article addresses may help you determine if it is relevant to your needs:
What is a good Research Question? It is a question that:
This blog post has tips on how to write a good research question, including examples of bad, good, and great questions.
To reduce bias, it may be best to pose your question in a neutral manner. Examples:
What is the question being addressed in the study you are reading? Compare:
When you read an article, answer (briefly) the following (source):
Finding a systematic review that addresses the question you are interested in can be very helpful: take a look at the search strategy and databases used in the systematic review for tips on your search.
It may be useful to have a structure to help guide you when searching.
When you formulate a research question, consider these elements:
Note: It is possible that not all of the above elements will be appropriate for your search topic.
This worksheet (docx) will take you through the process of formulating a search.
PICO is another popular way to structure a search.
PICO stands for:
Worksheet: Developing an Efficient Search Strategy Using PICO (docx): A fillable form that provides a PICO example and prompts you to document synonyms and MeSH headings.
Embase has a PICO search form to guide you.
SPIDER is a search structure used in qualitative research. SPIDER stands for:
Once you have a search strategy, you can try the Polyglot Search tool, which helps to translate a PubMed search into the correct syntax for several other databases, including Embase, Scopus, Web of Science, and more.
"Research users are not passive recipients of distilled wisdom, they are active agents of critique and creative analysis."
- from "How to 'QuantCrit:' Practices and Questions for Education Data Researchers and Users," W. Castillo and D. Gillborn, 2018.
Evaluation is about determining the quality, value, or importance of something in order to take action. It is underpinned by the systematic collection of information and evidence.
What is evidence?
All research is (potentially) "evidence" and there are no "perfect" studies.
Critically evaluating what you read will help any unearth biases or methodological shortcomings that may be present.
Examples of problematic methods descriptions. From: T. Greenhalgh. How to Read a Paper: The Basics of Evidence-Based Medicine and Healthcare. John Wiley & Sons, 2019.
Is there an agenda (bias)?
It is doubtful that any study of humans is without some kind of bias, either in the study design, or in the author's pre-existing beliefs. How bias in methodology was controlled and the significance of bias in any particular study is what is relevant. Also relevant is whether the researchers addressed their biases intentionally.
Things to consider:
Who pays for science? Does it matter? (There is evidence that it does matter).
Research is usually funded by:
This article (PDF) discusses the "manufactured uncertainty" created by industry groups that sponsor research and publishing on chemicals.
Is qualitative research "evidence"?
If your goal is to understand beliefs and meanings in the group with whom you are working, then qualitative studies can be important.
Reliability and validity
Reliable data collection: relatively free from "measurement error:"
Is the survey written at a reading level too high for the people completing it?
If I measure something today, then measure it again tomorrow using the same scale, will it vary? Why?
Validity refers to how well a measure assesses what it claims to measure:
If the survey is supposed to measure "quality of life," how is that concept defined? Is it measurable?
What to consider when looking at survey or estimated data:
How is race/ethnicity reported in the studies you read?:
Off-campus access is limited to current UC Berkeley faculty, staff and students. Choose one of the following methods:
Library Proxy (aka EZproxy):
When you click on a link to an article, database, etc., from a library web page. you will be prompted to authenticate via CalNet.
If you click on an article (etc.) link found via a search engine or a non-UCB Library webpage, you should use this bookmarklet to access the licensed resource.
Virtual Private Network (VPN):
Download and install the VPN client to allow access the UC Berkeley licensed resources.
Make sure you select Library Access - Full Tunnel VPN when you log on.
Students: Problems setting up Library Proxy or VPN? Contact your librarian, or Student Technology Services: (510) 642-HELP, or firstname.lastname@example.org.
The "Evidence Pyramid" is a graphic representation of strength of evidence of various publication types. A typical evidence pyramid looks like this:
However, recently a modified evidence pyramid has been proposed, which looks like this:
The proposed new evidence-based medicine pyramid. (A) The traditional pyramid. (B) Revising the pyramid: (1) lines separating the study designs become wavy, (2) systematic reviews are ‘chopped off’ the pyramid. (C) The revised pyramid: systematic reviews are a lens through which evidence is viewed. (from Murad MH, Asi N, Alsawas M, et al. New evidence pyramid. BMJ Evidence-Based Medicine 2016;21:125-127.
When a topic is new to you and you need an overview of the topic, encyclopediae and textbooks are great at giving an overview or introduction.
Use UC Library Search to find encyclopediae and textbooks.
For more detailed exploration of a topic, books provide the focus you want. UC Berkeley has millions of books!
Use UC Library Search to find books on your topic.
For lab research, handbooks and lab protocols provide information on the materials and procedures for experimental work.
The next format type is journals. They report on the findings of current research studies, offering the most up-to-date and detailed information on a topic.
A single journal issue will have many articles, and each article is devoted to a research study. There is a standard pattern in how journal articles are written, and knowing this pattern will help you find the information you need:
Finally, databases are what you use to find journal articles. Databases let you search across many (often millions) of journal articles to find the papers relevant to your research topic.
If you need data or statistics for your research topic, here are some places to start: