Public Health Law Research Guide

Identifying empirical studies

Empirical research uses quantitative or qualitative data to learn about the world – a very broad definition, but good empirical research also follows certain rules to ensure it is rigorous and reliable.

When conducting this research, you are looking for sources that report on a scientific study.  Lee Epstein and Gary King’s article The Rules of Inference, 69 U. Chi. L. Rev. 1 (2002), discusses, with examples, what constitutes “good” empirical research and how legal scholarship often does not qualify.  While the entire article is worth reading, some of their main points are that good empirical research:

• Is replicable and valid – the research method is described in enough detail that someone else could replicate the results. See Critically Assessing Empirical Studies for more details.
• Is peer reviewed – although a rarity in legal publications, journals in most other fields are peer-reviewed.
• Has a large and unbiased sample set and does not rely merely on string citations or “key” cases.
• Acknowledges uncertainties – because no research can incorporate all facts or account for all possible factors, the researcher needs to look for and acknowledge the choices and weak links in the research, as well as potential alternate reasons for the observed results.

For further information on this topic, the books Public Health Law Research: Theory and Methods (2013), available online and in print, and Legal Epidemiology: Theory and Methods (2023), available in print, are good resources.  

Important considerations:

• Use primary sources.  Preliminary research may yield news articles about or synopses of others’ research.  Rather than relying on other people’s summaries and interpretations, review the cited studies and publications so that you can evaluate the research methodology and form your own opinion as to the information’s value and reliability.

• Look at grey (gray) literature.  Sometimes useful information exists outside the realm of published, mainstream materials in what is called grey literature.  Industry, research institutes, nonprofits, and government entities all can generate reports, newsletters, and presentation materials that contain information unavailable elsewhere.  Grey literature will not be peer-reviewed, so you should evaluate its reliability and strength as you review it.

• Think about the types and locations of resources.  Not all relevant literature will be in law or public health publications.  To think more broadly about potential sources, consider what types of outcomes (i.e., health, behavioral, or financial) might occur as a result of a public health measure.  This can help determine where relevant literature may be found – whether medical journals, education publications, or government spending reports.  As an example, an anti-bullying public health law might have outcomes related to school graduation rates, time spent on discipline, or other outcomes that may be found in materials not specifically focused on public health law.

Some suggested places to start a search for reliable public health sources:

• Medline
  The US National Library of Medicine’s bibliographic database contains references to life sciences journal articles, with a biomed focus.  The Temple Libraries provide access to Medline via various platforms, which offer different search interfaces.  PubMed, a popular choice, searches "biomedical literature from MEDLINE, life science journals, and online books."

• SSRN
  The Social Science Research Network database contains scholarship in law, health and life sciences, health economics, and many other topics.  One of SSRN’s strength is its inclusion of working papers that cannot be found elsewhere.

• Google Scholar
  This search tool is especially useful for grey literature.

• Temple University Health Statistics and Data research guide
  This research guide links to health statistics from the local to the national level, as well as tools and data sets.

• Campbell Collaboration
  “The Campbell Collaboration is an international social science research network that produces high quality, open and policy-relevant evidence syntheses, plain language summaries and policy briefs.”  It publishes the journal Campbell Systematic Reviews and produces evidence and gap maps to show graphically where evidence does – and does not – exist.

• Cochrane Public Health
  Cochrane “support[s], facilitate[s], edit[s] and publish[es] systematic reviews of population level interventions that address the structural and social determinants of health, qualitative questions relevant to public health, and other questions that need an unbiased thorough approach.”  The Cochrane Public Health website's Resources and Guidance section includes both Cochrane's own publications and links to other public health review sources.

• The Community Guide
  “The Guide to Community Preventive Services (The Community Guide) is a collection of evidence-based findings of the Community Preventive Services Task Force.”  Its Publications page allows the user to sort by topic or perform simple searches.

Additional sources are discussed in Chapter 7 of The New Public Health Law: A Transdisciplinary Approach to Practice and Advocacy (2d ed. 2023), available in print and online.

Tips and tricks for finding sources:

• Find a previously-done literature review
  Finding work someone else did will save you time and effort, but be sure to update the review and to conduct additional searches on your own for missed materials.  Also, review the primary materials cited to form your own opinions on them.

• Chain citations forward and backward
  Use the materials you find as a springboard to find additional materials, both forwards and backwards.  First, when you find a good article - or one that's close to good - check the articles and other materials it cites; many also will be relevant.  In addition, look for articles that cite the good one you found.  Many databases - including Web of Science, PubMed, and HeinOnline's Law Journal Library - will tell you how many times the article you're viewing has been cited and will link to those citing articles.  Finally, PubMed offers suggestions of "similar articles" to the one you're viewing.

• Use Startpage instead of Google for internet searches
  Google identifies you and personalizes your search results based on your prior searches and clicks.  As a result, you can get boxed into a narrow set of search results even when conducting new searches.  Startpage uses Google’s search engine but anonymizes you so that you don’t get trapped in the Google filter bubble.

• Look at CVs
  Scholars tend to work on multiple projects in the same area.  If you find a study of interest, look for the authors’ CVs online and check whether they have published additional materials on the topic.

• Use DOIs to pull articles quickly
  Use the Find by Citation tool to find an article by its DOI number.