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How to instruct the database to include narrower terms in a MeSH thesaurus search and/or to retrieve only those terms considered main subject terms.
Ovid MEDLINE <1946 to Present>
Ovid Training Team
2024-10-27
Training
This Focused Search provides further background on the structure and system of the MeSH thesaurus. The MeSH thesaurus is a controlled vocabulary, based upon medical subject headings. It has been created and is maintained by the National Library of Medicine (NLM) in the USA. The MeSH thesaurus is a domain specific knowledge base curated by humans, that aids both document classification as well as discoverability and retrieval.
MeSH Structure and System
Ovid MEDLINE is Ovid’s rendering of the PubMed database, it too created and maintained by NLM. The content of this kind of bibliographic database consists, for the most part, of records of documents that have been indexed using a controlled vocabulary. A controlled vocabulary is a hierarchical term classification system where terms, representing a thing or concept, can be located within the controlled vocabulary system, along with its broader and narrower terms. Broader terms are those for which your chosen term is a narrower term or sub-concept. Narrower terms on the other hand are the narrower terms or sub-concepts of your chosen term.
Using MeSH for Targeted Searching
We have already seen how, on Ovid, you can use the Advanced Search search mode to locate a term in a specific field (i.e. migraine.ti., see line #1 in this Focused Search) or in a group of fields (i.e. migraine.mp., see line #2).
In the Advanced Search, with mapping turned on (which for most users is a default setting) you can search for a thing not just in terms of the characters that describe it i.e. ‘migraine’, but also in a conceptual sense. That is you are able to automatically include additional terms and phrases that more fully represent the concept that best describes the thing you are looking for. In this Focused Search the entry term for all 10 search lines, using the Advanced Search with mapping turned on, is migraine. With mapping turned on, our search journey starts and continues through the MeSH thesaurus where at various stages we are offered opportunities to expand upon or narrow the scope of our search (see lines #3 to #10).
To investigate this further, let’s consider the following research question and subsequent task.
Is acupuncture effective in the treatment of migraines? Find randomised controlled trials.
From the research question, let us describe the population group as ‘migraine sufferers’ and that by proceeding with the search term ‘migraine’ we are likely to capture a relatively high proportion of relevant documents.
Upon entering the term migraine into the Advanced Search search mode with mapping turned on, Ovid maps our entered term onto a MeSH term, in this case Migraine Disorders/ (see line #3). Clicking on the MeSH terms displays it in the context of its occurrence and positioning within the controlled vocabulary as displayed below. Here we can see that Migraine Disorders is a sub-term of the broader term, Headache Disorders, Primary. But Migraine Disorders is itself the broader term for its narrower terms, namely Alice in Wonderland Syndrome, Migraine with Aura, Migraine without Aura and Ophthalmoplegic Migraine.
The returned display, which highlights the mapped to term Migraine Disorders/, also tells us that a specific number of documents, indicated by the search results have been indexed with that specific term. In other words, the concept or idea represented by the term ‘migraine’ within a constellation of scope defining broader and narrower terms, has been identified in the database. This, as opposed to ‘just’ occurrences of the word ‘migraine’ as is the case in lines #1 and #2.
Explode and Focus Options
The MeSH thesaurus, both in terms of its structure and direct integration in Ovid MEDLINE, also facilitates systematic searching. The scope of a selected MeSH term can be expanded upon by selecting the Explode option next to the selected term. See the green highlighting in the screen shot above. MeSH terms displayed in a search strategy with the ‘exp’, as shown in line #5 of the displayed Focused Search, tells us that the total number of records returned for that search line includes the MeSH term along with its narrower terms. By contrast, selecting the Focus option, highlighted in purple above, reduces the scope of the term, whether exploded or not, to records where the selected MeSH term represents one of the main topics as described in the article. The ‘*’ character placed before the MeSH term, as displayed in line #4 , indicates that the search has been run with this more specific requirement in mind.
MeSH Subheadings
Each MeSH term has a collection of subheadings associated with it. The list of subheadings for the MeSH term Migraine Disorders is displayed in the screen shot below.
As part of MeSH thesaurus construction and maintenance, the indexers at NLM allocate subheadings to MeSH terms. Subheadings provide an additional means of further fine-tuning the context within which the MeSH term, i.e. the concept, is being sought. In the displayed Focused Search, lines #6, #7 and #8 return records that cover Migraine Disorders but specifically those related to the etiology, diagnosis and prevention and control of the condition respectively. It is also possible to select multiple subheadings as shown with respect to therapy, in line #9.
Practice Suggestions
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-10-27
Expiry Date: 2025-10-27
Ovid Training Team
OvidGO! / Skills Videos
What are Boolean Operators?
What is an adjacency operator?
What are wildcards?
Truncation of keywords
Phrase searching on Ovid
Subject heading searching
migraine.ti.
migraine.mp.
Migraine Disorders/
*Migraine Disorders/
exp Migraine Disorders/
exp Migraine Disorders/et [Etiology]
exp Migraine Disorders/di [Diagnosis]
exp Migraine Disorders/pc [Prevention & Control]
exp Migraine Disorders/dh, dt, th [Diet Therapy, Drug Therapy, Therapy]
exp Migraine Disorders/ or migraine.mp.
Database: Ovid MEDLINE <1946 to Present>
How to instruct the database to include narrower terms in a MeSH thesaurus search and/or to retrieve only those terms considered main subject terms.
This Focused Search provides further background on the structure and system of the MeSH thesaurus. The MeSH thesaurus is a controlled vocabulary, based upon medical subject headings. It has been created and is maintained by the National Library of Medicine (NLM) in the USA. The MeSH thesaurus is a domain specific knowledge base curated by humans, that aids both document classification as well as discoverability and retrieval.
MeSH Structure and System
Ovid MEDLINE is Ovid’s rendering of the PubMed database, it too created and maintained by NLM. The content of this kind of bibliographic database consists, for the most part, of records of documents that have been indexed using a controlled vocabulary. A controlled vocabulary is a hierarchical term classification system where terms, representing a thing or concept, can be located within the controlled vocabulary system, along with its broader and narrower terms. Broader terms are those for which your chosen term is a narrower term or sub-concept. Narrower terms on the other hand are the narrower terms or sub-concepts of your chosen term.
Using MeSH for Targeted Searching
We have already seen how, on Ovid, you can use the Advanced Search search mode to locate a term in a specific field (i.e. migraine.ti., see line #1 in this Focused Search) or in a group of fields (i.e. migraine.mp., see line #2).
In the Advanced Search, with mapping turned on (which for most users is a default setting) you can search for a thing not just in terms of the characters that describe it i.e. ‘migraine’, but also in a conceptual sense. That is you are able to automatically include additional terms and phrases that more fully represent the concept that best describes the thing you are looking for. In this Focused Search the entry term for all 10 search lines, using the Advanced Search with mapping turned on, is migraine. With mapping turned on, our search journey starts and continues through the MeSH thesaurus where at various stages we are offered opportunities to expand upon or narrow the scope of our search (see lines #3 to #10).
To investigate this further, let’s consider the following research question and subsequent task.
Is acupuncture effective in the treatment of migraines? Find randomised controlled trials.
From the research question, let us describe the population group as ‘migraine sufferers’ and that by proceeding with the search term ‘migraine’ we are likely to capture a relatively high proportion of relevant documents.
Upon entering the term migraine into the Advanced Search search mode with mapping turned on, Ovid maps our entered term onto a MeSH term, in this case Migraine Disorders/ (see line #3). Clicking on the MeSH terms displays it in the context of its occurrence and positioning within the controlled vocabulary as displayed below. Here we can see that Migraine Disorders is a sub-term of the broader term, Headache Disorders, Primary. But Migraine Disorders is itself the broader term for its narrower terms, namely Alice in Wonderland Syndrome, Migraine with Aura, Migraine without Aura and Ophthalmoplegic Migraine.
The returned display, which highlights the mapped to term Migraine Disorders/, also tells us that a specific number of documents, indicated by the search results have been indexed with that specific term. In other words, the concept or idea represented by the term ‘migraine’ within a constellation of scope defining broader and narrower terms, has been identified in the database. This, as opposed to ‘just’ occurrences of the word ‘migraine’ as is the case in lines #1 and #2.
Explode and Focus Options
The MeSH thesaurus, both in terms of its structure and direct integration in Ovid MEDLINE, also facilitates systematic searching. The scope of a selected MeSH term can be expanded upon by selecting the Explode option next to the selected term. See the green highlighting in the screen shot above. MeSH terms displayed in a search strategy with the ‘exp’, as shown in line #5 of the displayed Focused Search, tells us that the total number of records returned for that search line includes the MeSH term along with its narrower terms. By contrast, selecting the Focus option, highlighted in purple above, reduces the scope of the term, whether exploded or not, to records where the selected MeSH term represents one of the main topics as described in the article. The ‘*’ character placed before the MeSH term, as displayed in line #4 , indicates that the search has been run with this more specific requirement in mind.
MeSH Subheadings
Each MeSH term has a collection of subheadings associated with it. The list of subheadings for the MeSH term Migraine Disorders is displayed in the screen shot below.
As part of MeSH thesaurus construction and maintenance, the indexers at NLM allocate subheadings to MeSH terms. Subheadings provide an additional means of further fine-tuning the context within which the MeSH term, i.e. the concept, is being sought. In the displayed Focused Search, lines #6, #7 and #8 return records that cover Migraine Disorders but specifically those related to the etiology, diagnosis and prevention and control of the condition respectively. It is also possible to select multiple subheadings as shown with respect to therapy, in line #9.
Practice Suggestions
migraine.ti.
migraine.mp.
Migraine Disorders/
*Migraine Disorders/
exp Migraine Disorders/
exp Migraine Disorders/et [Etiology]
exp Migraine Disorders/di [Diagnosis]
exp Migraine Disorders/pc [Prevention & Control]
exp Migraine Disorders/dh, dt, th [Diet Therapy, Drug Therapy, Therapy]
exp Migraine Disorders/ or migraine.mp.
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-10-27
Expiry Date: 2025-10-27
Ovid Training Team
OvidGO! / Skills Videos
What are Boolean Operators?
What is an adjacency operator?
What are wildcards?
Truncation of keywords
Phrase searching on Ovid
Subject heading searching
Version: 2024-10-27
Visited:
OvidGo! - Wolters Kluwer - Health Learning, Research and Practice
OvidGO! Portal. Focused Searches: Knowledge Discovery with MeSH (Explode & Focus) – Ovid MEDLINE [Internet]. London (UK): Ovid Training Team (Editors); 2024 [updated 25 October 2024; cited 30 October 2024]. Available from: https://tools.ovid.com/ovidgo/searches/view.php?id=58
Version: 2024-10-27
Visited:
How to use the controlled vocabulary in Ovid MEDLINE to contrast terms, assess their coverage, relevance to the research question and then select them accordingly.
Ovid MEDLINE <1946 to Present>
Ovid Training Team
2024-10-27
Training
The structure, system and sheer depth of database controlled vocabularies also provides searchers with various means of selecting terms, of considering their relevance and of refining them so that they better suit the search at hand. To illustrate this, let us refer again to the following research question and subsequent task.
Is acupuncture effective in the treatment of migraines? Find randomised controlled trials.
Here we need to consider how to proceed with the term ‘acupuncture’. This Focused Search looks at how the MeSH thesaurus as an highly structured and contextually deep knowledge base can help researchers refine their search terms. And that via Ovid MEDLINE, the MeSH thesaurus knowledge base provides researchers with a means of being able to (a). navigate through it, (b). select specific terms and (c). deselect others.
Exact versus Near Matches
Entered into the Advanced Search with the mapping turned on, the entry term acupuncture yields a list of MeSH term possibilities as shown in the screen shot below. As marked by the ticked Select box, the entry term acupuncture is an exact match. The other possibilities are near matches.
From this initial display, or by running the MesH term search in Ovid MEDLINE (line #1), it is not possible to determine whether or not Acupuncture/ has narrower terms. Running the term again but with the Explode option activated, indicates that it does not (#2). However, Acupuncture Therapy/ does have narrower terms (compare lines #3 and #4), terms that might be more appropriate for the research question.
Learning with Scope Notes
The MeSH thesaurus created and cultivated by the NLM is an exceptionally information laden example of a controlled vocabulary. In addition to a hierarchical term classification scheme, rich structure and subheadings, MeSH terms also have scope notes allocated to them. This MeSH term specific annotation gives an indication of the coverage of the term (from the indexers point of view), flags points to note, provides information on the year of entry of the MeSH term into the thesaurus, indicates any previous indexing, gives references and lists other terms the given MeSH term would additionally capture when used in a search. In this Focused Search example the scope note for Acupuncture Therapy/ helpfully draws a distinction between the term ‘acupuncture’ meaning the specialty as opposed to ‘acupuncture’, a form of therapy. See lines #6 and #7.
Targeted Term Selection
In contrast to the MeSH term Acupuncture/ which has no narrower terms, Acupuncture Therapy/ has several. However, not all of them might be pertinent to the research question at hand. In Ovid MEDLINE it is possible to fully display the chosen MeSH term and all its narrower terms and their narrower terms, yet only select specific narrower terms. In the screen shot example below the Acupuncture Therapy/ narrower terms Electroacupuncture and Moxibustion as highlighted in red, have been excluded.
Practice Suggestions:
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-10-27
Expiry Date: 2025-10-27
Ovid Training Team
OvidGO! / Skills Videos
What is Ovid MEDLINE
Ovid MEDLINE segments explained
How to customize Ovid MEDLINE segments
How is indexing done in MEDLINE
Subject heading searching
Acupuncture/
exp Acupuncture/
Acupuncture Therapy/
exp Acupuncture Therapy/
acupuncture therapy/ or acupuncture analgesia/ or acupuncture, ear/ or meridians/ or acupuncture points/
Acupuncture/ [A sub-category of "Health Occupations"]
Acupuncture Therapy/ [A sub-category of "Complementary Therapies"]
Database: Ovid MEDLINE <1946 to Present>
How to use the controlled vocabulary in Ovid MEDLINE to contrast terms, assess their coverage, relevance to the research question and then select them accordingly.
The structure, system and sheer depth of database controlled vocabularies also provides searchers with various means of selecting terms, of considering their relevance and of refining them so that they better suit the search at hand. To illustrate this, let us refer again to the following research question and subsequent task.
Is acupuncture effective in the treatment of migraines? Find randomised controlled trials.
Here we need to consider how to proceed with the term ‘acupuncture’. This Focused Search looks at how the MeSH thesaurus as an highly structured and contextually deep knowledge base can help researchers refine their search terms. And that via Ovid MEDLINE, the MeSH thesaurus knowledge base provides researchers with a means of being able to (a). navigate through it, (b). select specific terms and (c). deselect others.
Exact versus Near Matches
Entered into the Advanced Search with the mapping turned on, the entry term acupuncture yields a list of MeSH term possibilities as shown in the screen shot below. As marked by the ticked Select box, the entry term acupuncture is an exact match. The other possibilities are near matches.
From this initial display, or by running the MesH term search in Ovid MEDLINE (line #1), it is not possible to determine whether or not Acupuncture/ has narrower terms. Running the term again but with the Explode option activated, indicates that it does not (#2). However, Acupuncture Therapy/ does have narrower terms (compare lines #3 and #4), terms that might be more appropriate for the research question.
Learning with Scope Notes
The MeSH thesaurus created and cultivated by the NLM is an exceptionally information laden example of a controlled vocabulary. In addition to a hierarchical term classification scheme, rich structure and subheadings, MeSH terms also have scope notes allocated to them. This MeSH term specific annotation gives an indication of the coverage of the term (from the indexers point of view), flags points to note, provides information on the year of entry of the MeSH term into the thesaurus, indicates any previous indexing, gives references and lists other terms the given MeSH term would additionally capture when used in a search. In this Focused Search example the scope note for Acupuncture Therapy/ helpfully draws a distinction between the term ‘acupuncture’ meaning the specialty as opposed to ‘acupuncture’, a form of therapy. See lines #6 and #7.
Targeted Term Selection
In contrast to the MeSH term Acupuncture/ which has no narrower terms, Acupuncture Therapy/ has several. However, not all of them might be pertinent to the research question at hand. In Ovid MEDLINE it is possible to fully display the chosen MeSH term and all its narrower terms and their narrower terms, yet only select specific narrower terms. In the screen shot example below the Acupuncture Therapy/ narrower terms Electroacupuncture and Moxibustion as highlighted in red, have been excluded.
Practice Suggestions:
Acupuncture/
exp Acupuncture/
Acupuncture Therapy/
exp Acupuncture Therapy/
acupuncture therapy/ or acupuncture analgesia/ or acupuncture, ear/ or meridians/ or acupuncture points/
Acupuncture/ [A sub-category of "Health Occupations"]
Acupuncture Therapy/ [A sub-category of "Complementary Therapies"]
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-10-27
Expiry Date: 2025-10-27
Ovid Training Team
OvidGO! / Skills Videos
What is Ovid MEDLINE
Ovid MEDLINE segments explained
How to customize Ovid MEDLINE segments
How is indexing done in MEDLINE
Subject heading searching
Version: 2024-10-27
Visited:
OvidGo! - Wolters Kluwer - Health Learning, Research and Practice
OvidGO! Portal. Focused Searches: Term Refinement and Targeted Selection (Term Hierarchies) – Ovid MEDLINE [Internet]. London (UK): Ovid Training Team (Editors); 2024 [updated 25 October 2024; cited 30 October 2024]. Available from: https://tools.ovid.com/ovidgo/searches/view.php?id=59
Version: 2024-10-27
Visited:
How to use the MeSH thesaurus’s scope notes to build up lists of free term search expressions associated with your MeSH terms.
Ovid MEDLINE <1946 to Present>
Ovid Training Team
2024-07-15
Training
A major strength of abstracting and indexing (A&I) databases, such as Ovid MEDLINE and Embase on Ovid, is that their enormous content is indexed against a controlled vocabulary or thesaurus. As discussed in previous Focused Searches, these knowledge resources are used to systematically organize, classify and give structure to the database’s content.
However, not all records can be captured using thesaurus based searches. To remedy this situation it is good practice to search on concepts, not only expressed by their equivalent thesaurus term description, but also using free terms. A ‘free term’ is a word or phrase that describes the thing you are searching for but is not dependent on being part of a controlled vocabulary. A free term search has the additional benefit that we can search for terms across all the database fields that make up the database record.
The question then arises how do we determine which free term words and phrases would be appropriate to use? We can of course simply add them ourselves, drawing them from our own knowledge of the subject matter. Another approach is to avail of the list of terms a thesaurus indicates that its thesaurus term covers. In Ovid MEDLINE, and more specifically the MeSH thesaurus, this information can be found in the respective MeSH term’s Scope Note as indicated below.
Clicking upon the ‘i’ icon displays the full entry for the MeSH term. The scope note describes, as the expression implies, the extent or scope of meaning associated with the term, additional notes on the term, the year of entry of the MeSH term into the thesaurus and a list of Used For terms.
These ‘Used For’ terms, as displayed in the screen shot below, are a list of term variations, singular or plural forms, alternative spellings and synonyms that the indexer watches for in the indexable medical literature. Then, due to their conceptual parity the indexer makes and marks the direct connection between these terms as used in the literature and the term in the thesaurus that, in effect, represents them. So for example, where an article talks of ‘sick headaches’ or ‘status migrainosus’ these articles will be captured by the thesaurus search Migraine Disorders/ but not necessarily by migraine*.ti,ab. or migraine*.mp.
The purpose of this Focused Search is twofold. Firstly, to flag scope notes as a source representing a comprehensive list of free terms that due to their close semantic connection to their associated thesaurus terms can help you supplement your thesaurus based searches. Secondly, to demonstrate that it is not necessary to try and render all the ‘Used For’ terms into a free term search expression. Particularly in the case of MeSH, closer examination shows that many such used for terms are entered twice, i.e. firstly in full and then as an inverted version. And that with truncation the overall number of term variants can be reduced. The screen shot below presents an example of how all the 35 Used For terms for Migraine Disorders/ can be condensed and rendered into a search expression as minimalist as (migraine$ or sick headache$ or status migrainosus).mp.
Book an Ovid Coaching session for this Focused Search to learn how to systematically convert the Used For Terms for both for the MeSH term Migraine Disorders/ and its exploded equivalent exp Migraine Disorders/ using a five step process so as to be able to construct the comprehensive concept searches as indicated in lines #1 to #3 and #4 to #6 respectively.
Step 1. Prepare the List of Used For Terms
Step 2. Remove the Inversions
Step 3. Truncate the Terms
Step 4. Construct the Search Expression
Step 5. Save the Search Expression in Line Format (Optional)
Practice Suggestions
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-07-15
Expiry Date: 2025-07-15
Ovid Training Team
Supplemental Information
How to systematically convert the MeSH Used For Terms into Free Term Searches
Ovid Online Help
Searching / Selecting a Search Mode / Search Tools / Scope Notes
OvidGO! / Skills Videos
Why use Ovid databases?
Subject heading searching
Truncation of keywords
Phrase searching on Ovid
Migraine Disorders/
(abdominal migraine$ or acute confusional migraine$ or cervical migraine syndrome$ or migraine variant$ or migraine$ or sick headache$ or status migrainosus).mp.
1 or 2
exp Migraine Disorders/
(abdominal migraine$ or acute confusional migraine$ or cervical migraine syndrome$ or migraine variant$ or migraine$ or sick headache$ or status migrainosus or alice in wonderland syndrome or acute onset aura migraine or basilar artery migraine or basilar migraine$ or basilar type migraine or classic migraine or classical migraine or complicated migraine or familial hemiplegic migraine$ or hemiplegic-ophthalmoplegic migraine or migraine aura without headache or migraine with acute onset aura or migraine with aura$ or migraine with prolonged aura or migraine with typical aura or prolonged aura migraine or typical aura without headache or common migraine$ or migraine without aura or ophthalmoplegic migraine syndrome$ or ophthalmoplegic migraine$).mp.
4 or 5
Database: Ovid MEDLINE <1946 to Present>
How to use the MeSH thesaurus’s scope notes to build up lists of free term search expressions associated with your MeSH terms.
A major strength of abstracting and indexing (A&I) databases, such as Ovid MEDLINE and Embase on Ovid, is that their enormous content is indexed against a controlled vocabulary or thesaurus. As discussed in previous Focused Searches, these knowledge resources are used to systematically organize, classify and give structure to the database’s content.
However, not all records can be captured using thesaurus based searches. To remedy this situation it is good practice to search on concepts, not only expressed by their equivalent thesaurus term description, but also using free terms. A ‘free term’ is a word or phrase that describes the thing you are searching for but is not dependent on being part of a controlled vocabulary. A free term search has the additional benefit that we can search for terms across all the database fields that make up the database record.
The question then arises how do we determine which free term words and phrases would be appropriate to use? We can of course simply add them ourselves, drawing them from our own knowledge of the subject matter. Another approach is to avail of the list of terms a thesaurus indicates that its thesaurus term covers. In Ovid MEDLINE, and more specifically the MeSH thesaurus, this information can be found in the respective MeSH term’s Scope Note as indicated below.
Clicking upon the ‘i’ icon displays the full entry for the MeSH term. The scope note describes, as the expression implies, the extent or scope of meaning associated with the term, additional notes on the term, the year of entry of the MeSH term into the thesaurus and a list of Used For terms.
These ‘Used For’ terms, as displayed in the screen shot below, are a list of term variations, singular or plural forms, alternative spellings and synonyms that the indexer watches for in the indexable medical literature. Then, due to their conceptual parity the indexer makes and marks the direct connection between these terms as used in the literature and the term in the thesaurus that, in effect, represents them. So for example, where an article talks of ‘sick headaches’ or ‘status migrainosus’ these articles will be captured by the thesaurus search Migraine Disorders/ but not necessarily by migraine*.ti,ab. or migraine*.mp.
The purpose of this Focused Search is twofold. Firstly, to flag scope notes as a source representing a comprehensive list of free terms that due to their close semantic connection to their associated thesaurus terms can help you supplement your thesaurus based searches. Secondly, to demonstrate that it is not necessary to try and render all the ‘Used For’ terms into a free term search expression. Particularly in the case of MeSH, closer examination shows that many such used for terms are entered twice, i.e. firstly in full and then as an inverted version. And that with truncation the overall number of term variants can be reduced. The screen shot below presents an example of how all the 35 Used For terms for Migraine Disorders/ can be condensed and rendered into a search expression as minimalist as (migraine$ or sick headache$ or status migrainosus).mp.
Book an Ovid Coaching session for this Focused Search to learn how to systematically convert the Used For Terms for both for the MeSH term Migraine Disorders/ and its exploded equivalent exp Migraine Disorders/ using a five step process so as to be able to construct the comprehensive concept searches as indicated in lines #1 to #3 and #4 to #6 respectively.
Step 1. Prepare the List of Used For Terms
Step 2. Remove the Inversions
Step 3. Truncate the Terms
Step 4. Construct the Search Expression
Step 5. Save the Search Expression in Line Format (Optional)
Practice Suggestions
Migraine Disorders/
(abdominal migraine$ or acute confusional migraine$ or cervical migraine syndrome$ or migraine variant$ or migraine$ or sick headache$ or status migrainosus).mp.
1 or 2
exp Migraine Disorders/
(abdominal migraine$ or acute confusional migraine$ or cervical migraine syndrome$ or migraine variant$ or migraine$ or sick headache$ or status migrainosus or alice in wonderland syndrome or acute onset aura migraine or basilar artery migraine or basilar migraine$ or basilar type migraine or classic migraine or classical migraine or complicated migraine or familial hemiplegic migraine$ or hemiplegic-ophthalmoplegic migraine or migraine aura without headache or migraine with acute onset aura or migraine with aura$ or migraine with prolonged aura or migraine with typical aura or prolonged aura migraine or typical aura without headache or common migraine$ or migraine without aura or ophthalmoplegic migraine syndrome$ or ophthalmoplegic migraine$).mp.
4 or 5
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-07-15
Expiry Date: 2025-07-15
Ovid Training Team
Supplemental Information
How to systematically convert the MeSH Used For Terms into Free Term Searches
Ovid Online Help
Searching / Selecting a Search Mode / Search Tools / Scope Notes
OvidGO! / Skills Videos
Why use Ovid databases?
Subject heading searching
Truncation of keywords
Phrase searching on Ovid
Version: 2024-10-27
Visited:
OvidGo! - Wolters Kluwer - Health Learning, Research and Practice
OvidGO! Portal. Focused Searches: Constructing Free Term Searches with MeSH (Scope Notes) – Ovid MEDLINE [Internet]. London (UK): Ovid Training Team (Editors); 2024 [updated 25 October 2024; cited 30 October 2024]. Available from: https://tools.ovid.com/ovidgo/searches/view.php?id=60
Version: 2024-10-27
Visited:
A model example providing a framework for constructing scalable search strategies using concept-based search blocks based on thesaurus and free text searches.
Ovid MEDLINE <1946 to Present>
Ovid Training Team
2024-10-27
Training
The purpose of this Focused Search is to provide an illustrative example of a framework for constructing scalable search strategies using concept-based search blocks. The aim is to show you how to create knowledge assets, important and valuable to you and/or the organization you work for and store them in Ovid for use, subsequent development, sharing and re-use.
As with previous Focused Searches we shall use the following the research question and accompanying task.
Is acupuncture effective in the treatment of migraines? Find randomized controlled trials (RCTs).
For the purposes of searching, the requirements were divided up into 3 major concepts, represented by the search entry terms: migraines, acupuncture and randomized controlled trials. The diagram below which reflects the focused search, indicates how a thesaurus search was conducted for each concept and combined with a corresponding free term search to arrive at a full set of results for each concept. The final line (#10) brings the concepts together in an all concepts result set.
Saving the individual concept searches as search blocks in My Workspace, will enable you to test and develop them further without always having to run the entire search strategy each time. Additionally, the individual search blocks can also be run in sequence or in combinations of your choice.
Practice Suggestions
The Search Blocks for Downloading
Concept 1 – Migraine – Version 1
Concept 2 – Acupuncture – Version 1
Concept 3 – RCTs – Version 1
Full Search – All Concepts
Further Versions of the RCT Search Block for Downloading
Concept 3 – RCTs – Version 2 – Search Filter – SIGN
Concept 3 – RCTs – Version 3 – Search Filter – Cochrane
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-10-27
Expiry Date: 2025-10-27
Ovid Training Team
How to build and share search strategies on Ovid® using concept searching
EMEA Webinar Series - 27th July 2023
OvidGO! / Skills Videos
What are Boolean Operators?
What is an adjacency operator?
What are wildcards?
Truncation of keywords
Phrase searching on Ovid
What is Ovid MEDLINE
Ovid MEDLINE segments explained
How to customize Ovid MEDLINE segments
How is indexing done in MEDLINE
exp Migraine Disorders/
(migraine$ or sick headache$ or status migrainosus).mp.
1 or 2
exp Acupuncture Therapy/
(acupuncture therap$ or acupuncture treatment$ or acupuncture analgesia or
ear acupuncture or electroacupuncture or meridian$ or acupuncture point$ or
moxibustion).mp.
4 or 5
Randomized Controlled Trial/
randomized controlled trial.mp.
7 or 8
3 and 6 and 9
Database: Ovid MEDLINE <1946 to Present>
A model example providing a framework for constructing scalable search strategies using concept-based search blocks based on thesaurus and free text searches.
The purpose of this Focused Search is to provide an illustrative example of a framework for constructing scalable search strategies using concept-based search blocks. The aim is to show you how to create knowledge assets, important and valuable to you and/or the organization you work for and store them in Ovid for use, subsequent development, sharing and re-use.
As with previous Focused Searches we shall use the following the research question and accompanying task.
Is acupuncture effective in the treatment of migraines? Find randomized controlled trials (RCTs).
For the purposes of searching, the requirements were divided up into 3 major concepts, represented by the search entry terms: migraines, acupuncture and randomized controlled trials. The diagram below which reflects the focused search, indicates how a thesaurus search was conducted for each concept and combined with a corresponding free term search to arrive at a full set of results for each concept. The final line (#10) brings the concepts together in an all concepts result set.
Saving the individual concept searches as search blocks in My Workspace, will enable you to test and develop them further without always having to run the entire search strategy each time. Additionally, the individual search blocks can also be run in sequence or in combinations of your choice.
Practice Suggestions
The Search Blocks for Downloading
Concept 1 – Migraine – Version 1
Concept 2 – Acupuncture – Version 1
Concept 3 – RCTs – Version 1
Full Search – All Concepts
Further Versions of the RCT Search Block for Downloading
Concept 3 – RCTs – Version 2 – Search Filter – SIGN
Concept 3 – RCTs – Version 3 – Search Filter – Cochrane
exp Migraine Disorders/
(migraine$ or sick headache$ or status migrainosus).mp.
1 or 2
exp Acupuncture Therapy/
(acupuncture therap$ or acupuncture treatment$ or acupuncture analgesia or
ear acupuncture or electroacupuncture or meridian$ or acupuncture point$ or
moxibustion).mp.
4 or 5
Randomized Controlled Trial/
randomized controlled trial.mp.
7 or 8
3 and 6 and 9
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-10-27
Expiry Date: 2025-10-27
Ovid Training Team
How to build and share search strategies on Ovid® using concept searching
EMEA Webinar Series - 27th July 2023
OvidGO! / Skills Videos
What are Boolean Operators?
What is an adjacency operator?
What are wildcards?
Truncation of keywords
Phrase searching on Ovid
What is Ovid MEDLINE
Ovid MEDLINE segments explained
How to customize Ovid MEDLINE segments
How is indexing done in MEDLINE
Version: 2024-10-27
Visited:
OvidGo! - Wolters Kluwer - Health Learning, Research and Practice
OvidGO! Portal. Focused Searches: Concept Searching (Search Block Construction & Use) – Ovid MEDLINE [Internet]. London (UK): Ovid Training Team (Editors); 2024 [updated 25 October 2024; cited 30 October 2024]. Available from: https://tools.ovid.com/ovidgo/searches/view.php?id=61
Version: 2024-10-27
Visited:
How to share searches for peer review, project-based search query construction, personal or group search block libraries as well as re-use.
Ovid MEDLINE <1946 to Present>
Ovid Training Team
2024-10-27
Training
Well-constructed search queries are valuable knowledge assets. Assets that can be built upon and re-used, both in a personal as well as an institutional context. To uphold their value it is important to be able to share them for peer review, for project-based search query construction as well as for building up personal or group search block libraries, supplementing information handling work-flows.
This Focused Search flags the three ways in which search histories can be saved and provides some practice exercises in conclusion.
How to share searches on Ovid
On the Ovid platform, searches, regardless of their size, can be easily shared using the Share Search History options. Listed below, these are platform inline tools to facilitate sharing and reproduction of search blocks and search strategies. They complement the external tools such as the Ovid Search History Launcher that can be found on the Ovid Tools & Resources Portal.
Share Search History: Email All Search History
This option enables you to email the complete search history to a recipient or recipients of your choosing, including a message text as deemed appropriate.
The recipient will receive the search in three different formats. Firstly, as a JumpStart link meaning that upon clicking the link, the search, as you have sent it to them, will run automatically in Ovid (bear in mind that this also assumes they are able to access Ovid). Secondly, the search query presented in the form of a table that can also be adapted using your regular word processor. Note too that the tabular version of the search query also carries a date stamp. Thirdly, the search query is also rendered as cleanly as possible, that is without search line item numbers and search line results, so that it can be easily copied and pasted into the Ovid Search History Launcher tool.
Share Search History: Copy Search History Link
This option condenses the search history into a single jumpstart link. The link and hence access to, and use of, the search itself can be shared as well as added to external documentation from where it can also be launched. This latter option also serves as an additional back up of your valuable knowledge assets.
Share Search History: Copy Search History Details
Similarly, this option enables you to copy the whole search together with its search line item numbers and search line results into a third-party application, such as Notepad or Word for preservation or adaptation or both.
Practice Suggestions
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-10-27
Expiry Date: 2025-10-27
Ovid Training Team
OvidGO! / Skills Videos
What are Boolean Operators?
What is an adjacency operator?
What are wildcards?
Truncation of keywords
Phrase searching on Ovid
Subject heading searching
exp Migraine Disorders
(migraine$ or sick headache$ or status migrainosus).mp.
1 or 2
exp Acupuncture Therapy/
(acupuncture therap$ or acupuncture treatment$ or acupuncture analgesia or ear acupuncture or electroacupuncture or meridian$ or acupuncture point$ or moxibustion).mp.
4 or 5
Randomized Controlled Trial/
randomized controlled trial.mp.
7 or 8
3 and 6 and 9
Database: Ovid MEDLINE <1946 to Present>
How to share searches for peer review, project-based search query construction, personal or group search block libraries as well as re-use.
Well-constructed search queries are valuable knowledge assets. Assets that can be built upon and re-used, both in a personal as well as an institutional context. To uphold their value it is important to be able to share them for peer review, for project-based search query construction as well as for building up personal or group search block libraries, supplementing information handling work-flows.
This Focused Search flags the three ways in which search histories can be saved and provides some practice exercises in conclusion.
How to share searches on Ovid
On the Ovid platform, searches, regardless of their size, can be easily shared using the Share Search History options. Listed below, these are platform inline tools to facilitate sharing and reproduction of search blocks and search strategies. They complement the external tools such as the Ovid Search History Launcher that can be found on the Ovid Tools & Resources Portal.
Share Search History: Email All Search History
This option enables you to email the complete search history to a recipient or recipients of your choosing, including a message text as deemed appropriate.
The recipient will receive the search in three different formats. Firstly, as a JumpStart link meaning that upon clicking the link, the search, as you have sent it to them, will run automatically in Ovid (bear in mind that this also assumes they are able to access Ovid). Secondly, the search query presented in the form of a table that can also be adapted using your regular word processor. Note too that the tabular version of the search query also carries a date stamp. Thirdly, the search query is also rendered as cleanly as possible, that is without search line item numbers and search line results, so that it can be easily copied and pasted into the Ovid Search History Launcher tool.
Share Search History: Copy Search History Link
This option condenses the search history into a single jumpstart link. The link and hence access to, and use of, the search itself can be shared as well as added to external documentation from where it can also be launched. This latter option also serves as an additional back up of your valuable knowledge assets.
Share Search History: Copy Search History Details
Similarly, this option enables you to copy the whole search together with its search line item numbers and search line results into a third-party application, such as Notepad or Word for preservation or adaptation or both.
Practice Suggestions
exp Migraine Disorders
(migraine$ or sick headache$ or status migrainosus).mp.
1 or 2
exp Acupuncture Therapy/
(acupuncture therap$ or acupuncture treatment$ or acupuncture analgesia or ear acupuncture or electroacupuncture or meridian$ or acupuncture point$ or moxibustion).mp.
4 or 5
Randomized Controlled Trial/
randomized controlled trial.mp.
7 or 8
3 and 6 and 9
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-10-27
Expiry Date: 2025-10-27
Ovid Training Team
OvidGO! / Skills Videos
What are Boolean Operators?
What is an adjacency operator?
What are wildcards?
Truncation of keywords
Phrase searching on Ovid
Subject heading searching
Version: 2024-10-27
Visited:
OvidGo! - Wolters Kluwer - Health Learning, Research and Practice
OvidGO! Portal. Focused Searches: Sharing and Re-Using Searches (Share Search History) – Ovid MEDLINE [Internet]. London (UK): Ovid Training Team (Editors); 2024 [updated 25 October 2024; cited 30 October 2024]. Available from: https://tools.ovid.com/ovidgo/searches/view.php?id=62
Version: 2024-10-27
Visited:
How to locate, display and make optimum use of all the ‘limits’ options for the database or databases you are searching in.
Ovid MEDLINE <1946 to Present>
Ovid Training Team
2024-10-27
Training
A previous Focused Search, Fine Tuning Searches Quickly (Limits) – All Databases looked at database ‘limits’ and how a pre-determined selection of limits are available to you for the database you are working in. While many abstracting and indexing (A&I) databases have some common limits, the full set of limits for the database is usually specific to the database in question. The full set of limits available to you for any given database on Ovid can be displayed by selecting the Additional Limits option in the initial limits display as highlighted below.
The Additional Limits screen opens up to display the full set of limits available for the database you are searching in, in this example Ovid MEDLINE. The display has two parts. The first part, as shown below are the list of limits that are usually displayed, i.e. by default, as the initial limits display screen.
The second part of the Additional Limits screen displays the other limits available for the database in question, in this case Ovid MEDLINE, as well as the selection options available for the said limit. In the example highlighted below, the selection options for the MEDLINE limit ‘Status’ (ST) are fivefold. In order to select the 4 options that correspond to non-MEDLINE records, tick the relevant boxes. Click on Limit a Search. The limit will be imposed on the most recent search expression in your list of searches, unless you have specified otherwise.
You can also place the limits, most useful to you, on the initial selection display by selecting the Edit Limits option. Your selection will remain as your initial display selection for the duration of your database session. After which they will return to and re-display the default selection.
For database administrators, please note however, that the default selection can be customized for you by Ovid Technical Support so that the default selection of limits better addresses your users’ needs.
Practice Suggestions
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-10-27
Expiry Date: 2025-10-27
Ovid Training Team
Ovid / Knowledge Community
How can I limit search results by a date range in Ovid?
OvidGO! / Skills Videos
What are Boolean Operators?
What is an adjacency operator?
What are wildcards?
Truncation of keywords
Phrase searching on Ovid
Subject heading searching
exp Migraine Disorders/
(migraine$ or sick headache$ or status migrainosus).mp.
1 or 2
exp Acupuncture Therapy/
(acupuncture therap$ or acupuncture treatment$ or acupuncture analgesia or ear acupuncture or electroacupuncture or meridian$ or acupuncture point$ or moxibustion).mp.
4 or 5
Randomized Controlled Trial/
randomized controlled trial.mp.
7 or 8
3 and 6 and 9
limit 10 to ("young adult (19 to 24 years)" or "adult (19 to 44 years)" or "middle age (45 to 64 years)" or "all aged (65 and over)")
limit 11 to chinese
Database: Ovid MEDLINE <1946 to Present>
How to locate, display and make optimum use of all the ‘limits’ options for the database or databases you are searching in.
A previous Focused Search, Fine Tuning Searches Quickly (Limits) – All Databases looked at database ‘limits’ and how a pre-determined selection of limits are available to you for the database you are working in. While many abstracting and indexing (A&I) databases have some common limits, the full set of limits for the database is usually specific to the database in question. The full set of limits available to you for any given database on Ovid can be displayed by selecting the Additional Limits option in the initial limits display as highlighted below.
The Additional Limits screen opens up to display the full set of limits available for the database you are searching in, in this example Ovid MEDLINE. The display has two parts. The first part, as shown below are the list of limits that are usually displayed, i.e. by default, as the initial limits display screen.
The second part of the Additional Limits screen displays the other limits available for the database in question, in this case Ovid MEDLINE, as well as the selection options available for the said limit. In the example highlighted below, the selection options for the MEDLINE limit ‘Status’ (ST) are fivefold. In order to select the 4 options that correspond to non-MEDLINE records, tick the relevant boxes. Click on Limit a Search. The limit will be imposed on the most recent search expression in your list of searches, unless you have specified otherwise.
You can also place the limits, most useful to you, on the initial selection display by selecting the Edit Limits option. Your selection will remain as your initial display selection for the duration of your database session. After which they will return to and re-display the default selection.
For database administrators, please note however, that the default selection can be customized for you by Ovid Technical Support so that the default selection of limits better addresses your users’ needs.
Practice Suggestions
exp Migraine Disorders/
(migraine$ or sick headache$ or status migrainosus).mp.
1 or 2
exp Acupuncture Therapy/
(acupuncture therap$ or acupuncture treatment$ or acupuncture analgesia or ear acupuncture or electroacupuncture or meridian$ or acupuncture point$ or moxibustion).mp.
4 or 5
Randomized Controlled Trial/
randomized controlled trial.mp.
7 or 8
3 and 6 and 9
limit 10 to ("young adult (19 to 24 years)" or "adult (19 to 44 years)" or "middle age (45 to 64 years)" or "all aged (65 and over)")
limit 11 to chinese
Primary: Michael Fanning
Secondary: Charlotte Viken
Review Date: 2024-10-27
Expiry Date: 2025-10-27
Ovid Training Team
Ovid / Knowledge Community
How can I limit search results by a date range in Ovid?
OvidGO! / Skills Videos
What are Boolean Operators?
What is an adjacency operator?
What are wildcards?
Truncation of keywords
Phrase searching on Ovid
Subject heading searching
Version: 2024-10-27
Visited:
OvidGo! - Wolters Kluwer - Health Learning, Research and Practice
OvidGO! Portal. Focused Searches: Refining Searches Systematically (Limits) – Ovid MEDLINE [Internet]. London (UK): Ovid Training Team (Editors); 2024 [updated 25 October 2024; cited 30 October 2024]. Available from: https://tools.ovid.com/ovidgo/searches/view.php?id=63
Version: 2024-10-27
Visited:
Ovid Customer Support, Database Size and Shape – Ovid MEDLINE, Ovid Expert Searches Portal, Version: 8th May 2023, Visited: 11th May 2023.
An Ovid Coaching session has its agenda driven by you, the participating librarian. Topics covered are ones that you choose.
They may be related to Ovid functionality, search modes, search techniques, Ovid Tools & Resources, learning materials etc..
To register for an Ovid Coaching session please fill in the contact form below. In the Your Comments box let us know what you would like to discuss and when.
An Ovid Trainer will get back to you to confirm details.
Focused Searches on OvidGO! consist of a comprehensive selection of database searches that are easily discoverable, accessible and actionable, that you can run directly on the Ovid platform with a single click. The curated and regularly reviewed portfolio of searches has been selected by the Ovid Training Team from various named and accredited sources. They include search filters, search strategies, search blocks and vary in size and format.
You can use all the searches within Focused Searches as standalone resources or in combination with the other knowledge and educational assets in the training and coaching activity areas which together make up the OvidGO! portal. Portrayed using a standardised ABC approach (see next section) developed by the Ovid Training Team, any Focused Search can also be quickly displayed on screen passively for consultation, comparative reference as well as teaching purposes. Each search has a background section which provides more detail about the search, its origin plus any noteworthy features and characteristics.
Full accreditation is given to the creator of the search as well as a live and actionable reference to the original source. Each search carries an OvidGO! citation and can be embedded in non-Ovid documentation by means of a dedicated and permanent link.
Developed by the Ovid Training Team, the ABC approach, which stands for Action, Background and Citation, represents the standard format for every search on Focused Searches. Regardless of its type, size or origin, the ABC formula provides for each search; a memorable point of access for both an overview of the search, accompanying information as well as a set of options for its use and re-use.
For example, if you want to view the search on your screen, simply select Actions/Display. If on the other hand you want to launch the search so that it runs and displays in Ovid, select Actions/Display. Once in Ovid, you could use the executed search in the development of your search strategy, save it in My Workspace or share it with colleagues.
Further options under the Actions tab include:
Selecting the Background tab will provide you with information on the search. These details include:
Selecting the Citation tab will display an OvidGO! citation for the search on Ovid and accompanying materials as displayed in Focused Searches. The current citation format is Vancouver.
The searches on Ovid, presented using our ABC format, can be used in a number of ways. These depend, of course, on what your objective is. They could include searching for literature systematically or getting to know an unfamiliar database or even for teaching database use to others.
For example, if you are building a search strategy which requires locating randomised controlled trials, you might want to select Actions/Launch for the Cochrane RCT Search Filter I and directly include it in your search strategy. Equally you might want to save it as a search block in My Workspace for later review, use or even sharing.
Alternatively, were you to be unfamiliar with, say APA PsycInfo, you could select Actions/Display for the Covid and Mental Health - APA PsycInfo search to see how comfortable you are with that database’s use of terms and phrases for the subject matter.
In terms of teaching scenarios, you could refer to the Search History Analysis Example search, where the Background tab provides information on how to use a search history and its systematic deconstruction to help users better understand how and why such searches are built in the way that they are.
If you need our assistance on any of the Focused Searches use cases mentioned above, simply select Actions/Ovid Coaching for the search that interests you.
Every search on Focused Searches is inspected by at least two members of the Ovid Training Team. Inspection involves two activities. First, ensuring that the search as captured and displayed in OvidGO! Focused Searches is a true and accurate version of the original (which often has had to be extracted and/or rebuilt from its original source, commonly a paper- and/or PDF-based publication). Second, that the search runs on Ovid in the selected database and using the syntax as employed by the original creator of the search.
The Ovid Training Team reviewers do not alter or make changes to the content of the original work. Where ambiguities or questions may arise, these are discussed with the original creator of the search for clarification and author-approved remedial action if necessary. Details of any such request for clarification may also be reported on in the Background information where relevant and appropriate.
In the case of search filter type searches included in Focused Searches, if the original author of the search has validated the search, this information is included in the Background information. The Ovid Training Team does not undertake any search validation independently of the creator of the original search. Again, it's worth iterating here that the objective of OvidGO!’s Focused Searches is to bring useful, instructive and highly regarded searches, already published or issued, closer to a user-level surface for greater exposure and positive consumption.
Currently, the searches on Focused Searches will be reviewed annually for relevancy and usage.
As part of The Focused Searches Project we are also reviewing all the searches in the Expert Searches section of the Ovid Tools & Resources Portal. The subsequent inclusion or exclusion of these expert searches into OvidGO!’s Focused Searches will depend upon the former’s current relevance, topicality and perceived usefulness. The Expert Searches on the Ovid Tools & Resources Portal marked for inclusion will be progressively migrated to Focused Searches on OvidGO! and re-structured and re-issued in accordance with the ABC approach as discussed above. Upon the conclusion of this part of the project, the Expert Searches on the Ovid Tools & Resources Portal will be removed from this site by the end of 2024.
If you have a favourite search currently in the Expert Searches on the Ovid Tools & Resources Portal and would like to have it included in Focused Searches on OvidGO!’s, please let us know.
Yes! We would very much like to hear from you. Ideally, recommended searches should be of benefit to a large number of Ovid users. They can nevertheless vary in terms of what they have been designed to achieve. They could be searches that add a more elegant set of lines to a systematic literature search. Or a set of controlled terms that work well across databases with (very) different controlled vocabularies. Or searches that best demonstrate an approach to database usage.
If you have a search that you would like to recommend, please let us know.
The Focused Searches on OvidGO! editors, Michael Fanning and Charlotte Viken, are contactable via their respective e-mail addresses or alternatively via [email protected] .