Global Index Medicus Help Guide

Basic Searches

1. Add your search terms to the search box.

   On the homepage
   

   On search results page
   

   • By default, your search terms will be searched for in the Title, Abstract, Subject, and Keywords of all articles in the database. This type of search is called Text Words and is denoted as: (tw:)  It will also search in the synonyms section of DeCS/MeSH terms.
   • For example: "rural health" AND nursing will search the Title, Abstract, Subject, Keywords, and synonyms for the exact phrase "rural health" and the word nursing; only articles containing both search terms in at least one of the fields listed above will be returned in the results.
   • Learn more about Boolean operators (AND, OR, and NOT). 
2. Explore initial results for relevant articles. 
3. Consider adding keywords from relevant search results to your search. 
4. Keep track of your searches in a text document to enable re-running them.

Learn more about how to: 

1. Refine search results.
2. Manage results (e.g., using filters and emailing your results). 
3. Go to full text.

Advanced Search Page

Use the Advanced Search page to combine concepts in a structured way or to limit a search to specific fields.

Combining concepts

Example search topic: Use of telemedicine for ischemic stroke. The concepts need to be joined with AND, and there are multiple ways to write each. The Advanced Search helps you combine them.

• Enter the synonyms for one concept in the first field.
  • Example: "ischemic stroke" OR "ischemic strokes" OR "ischaemic stroke" OR "ischaemic strokes"
• Leave the dropdown set to AND, then enter the synonyms for the second concept in the second field.
  • Example: telemedicine OR telestroke
• Repeat for each concept, then click Search to combine. GIM will add the appropriate parentheses.

Limit search to fields

By default, your search terms will be searched for in the Title, Abstract, Subject, Keywords and DeCS/MeSH synonyms of all articles in the database. This type of search is called Text Words and is denoted as: (tw:)

If you want to search different fields than those or just a subset of those, you can use the dropdown in Advanced Search to select a different field. Searchers working on a systematic review or other formal evidence synthesis may prefer to use mh:() OR ti:() OR ab:() OR kw:() to more closely match their other databases.

Fields and Abbreviations in Advanced Search

Each term is followed by the abbreviation GIM will recognize in parentheses. 

• Title, Abstract, Subject (tw:) 
  • Searches Title, Abstract, Subject, Keywords, and entry terms in DeCS/MeSH dictionary. 
  • Also known as Text Words. 
• Title (ti:) 
• Author (au:) 
• Subject descriptor (mh:)
  • MeSH/DeCS term; phrases must be in double quotes 
• Main subject (mj:)
  • Main topic(s) of article, based on MeSH/DeCS terms; the equivalent of [Majr] in PubMed
• Abstract (ab:)
• Author keywords (kw:)
• Journal (ta:)
• Publication date (da:)
  • For all months of one year, use the year followed by *. Example: 2021*
  • For all records from a particular month through the present day, use the year and month followed by *. Example: 202102* for all records since the start of February 2021
  • For a span of years that does not go to the present day, use year cluster. Example: year_cluster:[YYYY TO YYYY] This is how the year range filter will format the string.
• Publication country (cp:)
  • Terms must be in capital letters and in quotes. Example: cp:("BRAZIL")
  • Note: not reliable for countries outside of Latin America
• Subject limits (sh:)
  • Age, sex, and human/animal as in the filter on the results page
• Affiliation country (pais_afiliacao:)
  • Dropdown option "pais_afiliacao:" does not work; use field tag afp: instead. Example: afp:(Brazil)
  • Note: not reliable for countries outside of Latin America
• Unique identifier (id:) 
  • Number assigned to the article within GIM. Example: id:(biblio-1393000)

The abbreviations for these fields can be built into the text of a complex search if it is necessary.

Complex Searches

“Complex searches” refers to searches that join two or more concepts, or include multiple DeCS/MeSH terms and keyword terms. They may be new searches or translations of searches initially developed in other databases.

For these, we recommend building your search in a Word or Google document, or other text editor. GIM does not provide a search history for combining strings. The Search Details box displayed on the search results page allows you to edit your most recent search. 

Process

For each concept:

1. Identify your DeCS/MeSH terms, also called subject headings or subject descriptors. 
   • Note: Pressing Enter will stop the lookup and clear the search box.
2. Copy the category number followed by a * for any that need to include narrower terms and paste into your document. For an explanation of narrower terms, visit "Hierarchy" in What else could I need to know?
   • You may use mh:( ) to group these or paste your term(s) into the Advanced Search page with the Subject field selected. 
   • Example search strings:
     PubMed search: "Chlamydia Infections"[Mesh:NoExp] OR "Lymphogranuloma Venereum"[Mesh] OR "Urinary Tract Infections"[Mesh] OR "Vaginosis, Bacterial"[MeSH]
     GIM search (translated from PubMed search above): mh:(C01.150.252.734.301 OR C01.150.252.734.301.490 OR C01.915* OR C01.150.252.954) 
   • Note that for terms where you do not need the narrower terms or that do not have narrower terms, you may use either the phrase or the code without a *. This string will produce the same results as the string above:mh:("Chlamydia Infections" OR "Lymphogranuloma Venereum" OR C01.915* OR "Vaginosis, Bacterial")
3. In your document, join your keyword terms with OR using appropriate syntax. 
   • If these may be searched in title, abstract, author keywords, and subject headings, use tw:( ) to group these.
   • If you wish to limit it to title, abstract, and author keywords, use ti:( ) OR ab:( ) OR kw:( )
   • More search fields detailed above.
   • Example search strings: 
     PubMed search: "urinary tract infection*"[tiab] OR "urogenital infection*"[tiab] OR bacteriuria*[tiab] OR pyuria[tiab] OR "bacterial vaginosis"[tiab] OR "BV"[tiab]
     GIM search (translated from PubMed search above): tw:("urinary tract infection" OR "urinary tract infections" OR "urogenital infection" OR "urogenital infections" OR bacteriuria* OR pyuria OR "bacterial vaginosis" OR "BV")
4. Join the DeCS block and the keyword block with OR
5. Enclose the whole string within parentheses.
   • Example search string: 
     (mh:(C01.150.252.734.301 OR C01.150.252.734.301.490 OR C01.915* OR C01.150.252.954) OR tw:(chlamydia OR "urinary tract infection*" OR "urogenital infection*" OR bacteriuria* OR pyuria OR "bacterial vaginosis" OR "BV"))
6. Repeat for each concept, then join the concepts with AND
7. Recommended: Copy the search and paste it into Medsyntax to check for unbalanced quotation marks and parentheses. GIM will not provide an error notification if they are unbalanced but errors will affect your search.
8. Once your search is built in another document, you may copy and paste it into either search bar to run it and view the results.

By searching Global Index Medicus (GIM), you can search any or all the following regional databases. 

• African Index Medicus (AIM) 
• Index Medicus for the Eastern Mediterranean Region (IMEMR) 
  • GIM is three years behind on adding the latest research from IMEMR in GIM as of March 2024. Search IMEMR directly to view the latest research! 
• Index Medicus for the South-East Asia Region (IMSEAR)
  • GIM is two years behind on adding the latest research from IMSEAR in GIM as of March 2024. Search IMSEAR directly to view the latest research! 
• Latin America and the Caribbean Literature on Health Sciences (LILACS)
• Western Pacific Region Index Medicus (WPRO)

• GIM uses DeCS/MeSH for controlled vocabulary.
  • DeCS stands for Descritores em Ciências da Saúde (Portuguese), Descriptores en Ciencias de la Salud (Spanish), and means Health Science Descriptors (English).
  • MeSH stands for Medical Subject Headings.
• Controlled vocabularies
  • Are often generally referred to as Subject Headings, and are also called Subject Descriptor in GIM.
  • Attempt to designate one term per concept and to make all articles in the database related to that concept findable by searching the database for the controlled vocabulary term.
  • To learn more, jump to Deep Dive into Controlled Vocabulary.
• Important notes: 
  • Not every article will have DeCS and/or MeSH terms assigned to it. 
  • You may not agree with the indexer (person who assigns controlled vocabulary to articles), but you must use the terms as they're defined and exactly how they're spelled.
  • Searching with a combination of DeCS/MESH and text words (words in titles, abstracts, and keywords) will retrieve the most complete results!

Recommended Use

• Use both keywords and controlled vocabulary. 
• Search the DeCS/MeSH "Subject descriptor lookup" for relevant terms and add them to your search (you do not get to select any term, you must use an existing DeCS/MeSH term). 

Finding DeCS/MeSH Terms

1. From GIM's homepage, click Search by DeCS/MeSH descriptors above the search box, or from the search results page, click on the Subject descriptor lookup link above the search box. 
2. Then type the term into the "Subject descriptor lookup" box. 
   • Note: Pressing Enter will stop the lookup and clear the search box.
3. Select from the dropdown. 
4. Confirm that the definition listed matches your subject OR
5. Explore narrower and broader terms in the DeCS/MeSH hierarchy.
   • When a term is in multiple hierarchy trees, the narrower terms sometimes differ depending on which hierarchy tree you look in.
   • Select the broader term in each tree to reveal your term's narrower terms and make sure that all are acceptable.
   • Navigate by selecting terms within the tree; avoid using your browser's back button.
6. Optional: Under the definition of the selected term, the section "Restrict search by these aspects" refers to Subheadings and Qualifiers. Learn more about these below. 

Using DeCS/MeSH Terms

1. If you are not familiar with working with MeSH or other subject headings, you may wish to use the more in-depth guidance in What else could I need to know?
2. DeCS/MeSH terms can be written as their name or as their category number.
3. Unlike PubMed, GIM does not automatically explode DeCS/MeSH terms to include its narrower terms. To explode the term, use the category number.
   • Example:
     • With explosion: The equivalent of "Renal Dialysis"[Mesh] would be mh:E02.870.300*.
     • Without explosion: The equivalent of "Renal Dialysis"[Mesh:noexp] would be mh:E02.870.300 or would be mh:"Renal dialysis".
     • If you use the category number of the descriptor, do not use quotes around it.
   • Please note: The asterisk for explode does not work with text descriptor and it may make the website hang if you try. 
4. What I should do if there is more than one Category for my DeCS/MeSH term? Should I search with each code?
   • When a term appears in multiple hierarchy trees, it will have multiple category codes. Example: "Spinal Cord Injuries" is in trees for "Spinal Cord Diseases", "Trauma, Nervous System", and "Wounds and Injuries".
   • You only need to use one category code for your term.
   • Sometimes the narrower terms differ depending on which hierarchy tree it is in. Select the broader term in each tree to reveal your term's narrower terms and make sure that all are acceptable. Navigate by selecting terms within the tree, avoiding using your browser's back button.
   • Example:
     • I am considering using the DeCS/MeSH term "Blood Pressure".
     • “Blood Pressure” is a narrower term under "Vital Signs" and under "Hemodynamics".
     • Under “Vital Signs”, the category number for "Blood Pressure" is  E01.370.600.875.249. It has no narrower terms. A search on mh:(E01.370.600.875.249*) returns 10,044 results.
     • Under “Hemodynamics”, the category number for "Blood Pressure" is  G09.330.380.076. It has the narrower terms "Arterial Pressure", "Pulmonary Wedge Pressure", and "Venous Pressure". A search on mh:(G09.330.380.076*) returns 13,610 results.
     • If I want to also include the DeCS/MeSH terms "Arterial Pressure", "Pulmonary Wedge Pressure", and "Venous Pressure", the category number for "Blood Pressure" under "Hemodynamics" is the better choice.
   • You can also check the narrower terms for MeSH terms in NNLM's MeSH dictionary. The tree numbers for each entry correspond to GIM's category numbers.

Narrowing Concepts by Subheadings or Qualifiers

• Subheadings are controlled similar to the rest of the controlled vocabulary.
  • I.e., there are a limited number controlled by the vocabulary's organization.
  • Not every DeCS/MeSH term will have all subheadings available
    • Check the term's entry in the "Subject descriptor lookup" to determine which subheadings can be applied to it. 
    • Example: There are no articles published about the DeCS/MeSH term Cell Phones with the subheading Etiology, so you cannot select Etiology as a subheading for the DeCS/MeSH term Cell Phones. 

Subheadings with a DeCS/MeSH Term

• When a subheading is added to a subject heading, the database retrieves articles tagged with the selected DeCS/MeSH term that also have the selected subheading assigned to that particular DeCS/MeSH term. 
• You may find and add subheadings when viewing a term from the "Subject descriptor lookup" described above under "Finding DeCS/MeSH Terms". 
• Subheadings can be used with the word version of DeCS/MeSH descriptors but not the category number of the descriptor.
  • Example: mh:("Cleft Palate/EP"), which can also be searched as mh:("Cleft Palate/epidemiology").
  • Because of this, if you want to include the narrower terms for your DeCS/MeSH term, you must list each, applying the subheading to each. Example, applying the Drug Effects subheading to Blood Pressure and its narrower terms: mh:("Blood Pressure/DE" OR "Arterial Pressure/DE" OR "Pulmonary Wedge Pressure/DE" OR "Venous Pressure/DE")
  • For the two-letter tags, see the MeSH table of qualifiers.
  • If using the non-English DeCS term, use the two-letter tag rather than the whole word (EP, not epidemiology).
    • For example: write as mh:("Fissura palatina/EP") not as mh:("Fissura palatina/epidemiology").

Floating Subheadings

• In contrast, when a floating subheading is added to a search (not a particular subject heading), the database retrieves articles tagged with the selected subheading attached to any DeCS/MeSH term. 
• Locate the subheading in the "DeCS/MeSH descriptors lookup". Use the category number with mh: to search.
  • For example, mh:Q55.010 searches on the floating subheading Epidemiology. 

Deep Dive into Controlled Vocabulary

Click to expand and learn more about controlled vocabulary in Global Index Medicus (GIM).

Learn more about managing results, like using the filters on the search results page! 

Syntax refers to how the user must enter information into the database to change the meaning and results of their search. 

Global Index Medicus (GIM) uses different syntax than other databases. Below are some elements to keep in mind when constructing a new search or translating from another database.

Search Details Box

The Search Details box appears on the side of the search results page. You may edit your search in this box and review how GIM added syntax to your search string (like parentheses and field tags).

Quotes

• To perform an exact phrase or word search, phrases or words must be enclosed in quotes; the AND operator between the words in a phrase is assumed otherwise.
  • Example: tw:(calcium blocker OR calcium blockers) will be interpreted as tw:(calcium AND (blocker OR calcium) AND blockers) 
  • This revised search would likely retrieve results closer to what the user intended: tw:("calcium blocker" OR "calcium blockers")
• Quotes must be straight (simple) quotes, not curly quotes (also known as smart quotes).
  • Example: "anti depressants" (note straight quotes), rather than “anti depressants” (note curly or smart quotes). 
  • How to turn off smart quotes in Microsoft Word.
• Phrases in GIM can include words that are "stop words" in PubMed, and these searches with quotes are interpreted as exactly that phrase in GIM. In other databases, stop words like 'the' and 'of' are ignored; GIM does not do this. 
  • Example: "women in the hospital" will not be searched in PubMed but will be searched in GIM.

Hyphens

• Hyphens do not work for creating phrases or adding prefixes; the hyphens will be ignored and the words will be searched as if there were an AND between them. Enclose the phrase or word in quotes.
  • Example: pre-hospital will be searched as pre AND hospital; use "pre-hospital" or "pre hospital" to avoid the assumed AND operator. 

Truncation

• The US dollar or asterisk symbols, i.e., $ or *, can be used at the end of a term to stand in for one or more letters. It cannot be used within quotes.
  • Example: "community health worker" OR "community health workers" not "community health worker*".
  • Because of this, your GIM search may be longer than the equivalent search in another database. That is OK! It can accept long search strings
    • Reminder: Keep track of your search in another document because GIM won't save it for you.

No stemming or lemmatization

• Stemming and lemmatization refers to a function of other databases that automatically include variations on search terms, such as different verb forms.
  • Example: GIM does not return a search for treating with other forms like treat, treats, and treated; these must be added to the search individually or with the truncation symbols described above. 
  • Example: GIM also does not retrieve alternate spellings, like American and British spellings (e.g., pediatrics/paediatrics, behavior/behaviour), unless you add the alternatives to your search. 

No proximity searching

• Web of Science and some other databases allow you to search for words within a certain number of words of each other. GIM does not do this.

Using NOT

• GIM uses AND NOT rather than NOT. 
• Learn more about the risks of using NOT in your search. 
• AND NOT can be used anywhere that NOT would be used in another database search, including in double-not exclusion using MeSH/DeCS terms.
  • Example: NOT ("Animals"[Mesh] NOT "Humans"[Mesh]) would be written AND NOT ((mh: B01.050*) AND NOT mh:(Humans))

No warnings about errors

GIM will not notify you if there are structural errors in your search. It will interpret the search as well as it can, which may produce results that don't make sense. Use your judgement: if you get 0 results or far more results than seem likely, there may be an error in your string.

Unbalanced parentheses or quotation marks are among the errors that can dramatically alter your results. Paste your search string into the Medsyntax editor tool to check for these issues.

Hanging Boolean operator

A search string that ends with an OR or an AND will return unpredictable results.

The page is taking a long time to load

There are two main times this occurs:

• After the researcher used the browser back button when in the Search Descriptor Lookup. While in part of GIM, navigate using broader and narrower terms or by searching on your term again instead of using the back button.
  • If you used the back button and it is not resolving, use the forward button on your browser.
• When running a complex or very long search. This will usually resolve on its own after a few minutes, producing the results of the search.

Learn more about troubleshooting your search and results. 

No Search History

GIM does not save your search history nor display past searches within the session. 

Some browsers will cache your search string for a time. 

Reporting Your Search Strategy

GIM displays your current search string on the search results page. Look for Search Detail and copy the contents of that box to report your search for publication or to come back to and continue editing another day.