Skip to Main Content

_PSYC5131: Meta Analysis: Theory and Practice — Developing & Documenting Your Search Strategy

Library research guide for students in PSYC 5131.

How Do You Start?

Where do you begin when developing a search strategy? Start from what you know! You probably have a few articles you feel are right on target for your research question, or at least ones that are close to your area of interest. You might have literature reviews (standard or systematic) that relate to it. All of those will yield valuable terminology, authors, references, and other information that can help you design an effective search.

You'll start with lots of exploratory searches to determine the most useful vocabulary and databases on which to focus your efforts. The more thoroughly you document your efforts, the more comprehensive and successful your final searches will be. Below are some strategies that will help you with this process. 

Create a Concept Table

You'll be crafting a complex search strategy. Creating a concept table is one effective way to ensure your search is thorough and replicable. You'll use it to define the main ideas in your research question and track all the terminology you've used.

You can open and copy a concept table (either the Sheets or Docs version, depending on your preference) to your own Google Drive to develop your concept table in preparation for searching.

Planning Your Search: Keywords

There are two kinds of search terms: keywords and controlled vocabulary.

  • Keywords are any words you can think of about your topic. They can include scholarly or technical language or words a layperson might understand.
  • Controlled vocabulary, sometimes referred to as subject headings or descriptors, are the standardized terminology used by databases. These are generally organized in a hierarchy and explain what the terms mean and how they are interrelated. Most databases have a unique controlled vocabulary. That includes PubMed, which uses MeSH, and APA PsycInfo, which uses the APA Thesaurus of Psychological Index Terms, the two databases I'll be covering in detail on this guide.

When you being brainstorming keywords:

  • Identify the main ideas of your research question
  • In your concept table, write down literally any word or phrase that might be used to describe each component of the question
  • Lots of words may be written in different ways, such as differences in spelling, or singular and plural forms; see the Different Forms of the Same Word tab in this box for some suggestions of how to deal with that

Watch this short video to see how you might approach this process in your concept table!

Consider whether there are different forms of a word that interests you. In library databases, searching for any ending of a word is called "truncation." Frequently you can use a * to truncate a word, but the symbol can vary among different databases. In some cases, you can use a "wildcard" to find alternative spellings that fall inside a word, rather than at the end.

Some examples are below. Different databases allow for different truncation and wildcard options. In the examples below, you'll notice that PubMed allows for truncation (use the * symbol) but not wildcard searching. PsycInfo allows for both: * for multiple characters, # for one optional character, and ? for exactly one character.

Terms may be spelled differently depending on the researchers' language background

  • ischemic vs. ischaemic
    • In PubMed, search ischemic OR ischaemic
    • In PsycInfo, search isch#emic

Abbreviations may be useful

  • COPD vs. chronic obstructive pulmonary disease
    • In PubMed or PsycInfo, search COPD OR "chronic obstructive pulmonary disease"

Singular, plural, and more

  • physiology vs. physiological
    • In PubMed or PsycInfo, search physiol*
  • stroke vs. strokes
    • In PubMed or PsycInfo, search stroke*

Some words have even more forms

  • anemic vs. anemia vs aenemic vs. aenemia
    • In PubMed, search anemi* OR aenemi*
    • In PsycInfo, search a#nemi*

Documenting Your Search

In an evidence synthesis like a meta-analysis, it's vital to document:

  • Where you searched
    • This could be specific databases, but it would also include things like Google Scholar or other grey literature sources you used
  • What search strategies you used
    • Your concept table is essential to keep track of the terminology you have used (and what you've decided not to use) in your searching
    • You also need to track exactly how you searched: the exact strategy for how you combined your search terms; the easiest way to do this is to copy the line-by-line search strategy you used in each database when you run it
  • How many citations you found and retained at various stages of your process, starting with your searches
    • A meta-analysis requires you to track how many search results you got from each place you searched, how many you had after deduplication, how many were retained at each stage of screening, and how many you ultimately analyzed

A common reporting mechanism for this is PRISMA (now PRISMA 2020); the PRISMA-S extension is designed to provide the most accurate and replicable reporting of your search