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Short Term Educational Experiences for Research in Environmental Health (STEER): Starting Library Research

Welcome to the Library Session for STEER!

Dinosaur in VLSB; click for library home page

Presented by Michael Sholinbeck (

The Scientific Literature: Books, Handbooks and Protocols, Articles

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.

For more detailed exploration of a topic, books provide the focus you want.

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:

  • An article’s introduction explains the context of the work and the importance of the research
  • The materials and/or methods section describes the experimental procedures
  • The results report on the data and the outcomes of the work
  • The discussion section interprets the results, whereby the authors explain the meaning and the implications of the research
  • Lastly, there are references to the scholarly works (other articles, etc.) used by the authors

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. PubMed, Web of Science, and Embase are examples of article databases at UC Berkeley.

The Library catalog

Books, handbooks, etc. may be found in OskiCat, the current UC Berkeley library catalog.

On July 27, 2021, OskiCat is going away, and a new UC-wide catalog makes its debut, called UC Library Search.

About Your Topic

What to consider when thinking about your research topic
Much current research in environmental health is interdisciplinary.
The terms you use when searching PubMed, Web of Science, or other databases may need to include concepts from different fields of science.

Is your topic researchable?
  Effects of vehicular emissions from 1995 Toyotas on elderly women in Berkeley
  Health effects of seasonal variation in PM2.5 levels in the San Francisco Bay Area
  Air pollution in the United States

Information on chemicals/substances
Before you delve into the research literature on a topic, it can be helpful to get some basic information on the substance(s) of interest.

  • ChemIDplus
    Search over 400,000 chemicals by chemical name, registry number, molecular formula, structure, LD50, physical/chemical properties, molecular weight, and more. Links to other databases with information on carcinogenicity, toxicity, occupational health, etc.

Let's talk about indexing!
  Do you want articles on HIV (a virus) or articles on HIV diseases?
  Do you want articles on nanofibers or articles on nanofibres?
  Is lead a noun or a verb?

Indexing means a controlled vocabulary (a finite list of terms) is used to assign subject terms to articles.
Controlled vocabulary schemes are often hierarchical; any given term will have broader and (possibly) narrower terms. Example:

  • Environmental Pollution > Air Pollution > Indoor Air Pollution

Subject terms tend to have a single, unambiguous definition. Example:

  • Air Pollution: "The presence of contaminants or pollutant substances in the air that interfere with human health or welfare, or produce other harmful environmental effects. The substances may include gases particulate matter, or volatile organic chemicals."

Subject terms may also be called thesaurus terms, descriptors, or (in PubMed) Medical Subject Headings (MeSH).

Critically Evaluating What You Find

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

Is there an agenda (bias)?
It's 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's relevant. 

Things to consider:

  • The question being addressed: What kind of research gets funded?
  • Publication bias: Research that shows no effect tends not to get published
  • Conflict of interest, author affiliation, source(s) of funding: Does the researcher have a vested interest in the outcome?
  • Documentation and assumptions: Are all stated "facts" referenced?
  • Peer review: Peer review refers to a process whereby a scholarly work (ie, an article) is reviewed and critiqued by experts to ensure it meets some standards of acceptance before it is published. Does this process make for better science?
  • Authority: Does the researcher have the knowledge to work in this area?
  • Significance of a single study: Science is an incremental process; one study rarely "changes everything"

Who pays for science? Does it matter?  (There is evidence that it does matter)
Research may be funded by:

  • Government
  • Industry/trade groups
  • Private foundations/associations
  • etc.

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:

  • Look at sample sizes and survey response rates - representative of your population? Enough responses to be valid?
  • Who was surveyed? - representative of population being compared to? Include group you are interested in?
  • Were the survey respondents from heterogeneous groups? Do the survey questions have a similar meaning to members of different groups?
  • How was survey conducted? Via telephone? - Many people only have cell phones. Random selection or targeted group?
  • What assumptions and methods were used for extrapolating the data?
  • Look at definitions of characteristics - Does this match your own definitions?
  • When was the data collected?

Literature Review Tips Handouts

Ten simple rules for writing a literature review.
Pautasso M. PLoS Comput Biol. 2013;9(7):e1003149. doi:10.1371/journal.pcbi.1003149

Conducting the Literature Search.
Chapter 4 of Chasan-Taber L. Writing Dissertation and Grant Proposals: Epidemiology, Preventive Medicine and Biostatistics. New York: Chapman and Hall/CRC, 2014.

A step-by-step guide to writing a research paper, from idea to full manuscript. Excellent and easy to follow blog post by Dr. Raul Pacheco-Vega.