For each database you search, the structure of the search strategy remains the same. However, all databases have a slightly different search interface and offer slightly different search options. It is important that you explore the search options for each database you will search for the systematic review, and adapt the search strategy accordingly.
Most databases use unique controlled vocabulary to index their articles - for each database adapt the controlled vocabulary terms. For more details on the controlled vocabulary terms for different databases, see Step 4.
The fields you can search free-text terms (or the combination of them) vary between the databases. For more details on the search fields available for different databases, see Step 5.
Different databases offer different wildcard characters and commands. For more details on differences between databases for phrase searching, truncation, wildcards, Boolean and proximity operators, see Step 6 and Step 7.
The types of pre-set limits/filters vary across the databases. For more details on limits, see Step 8.
There are various translation tools available that can help you translate the search strategy from one database to another.
None of these tools are perfect and you still need to understand how the databases work.
Note! You need to report on the use of automation tools as per the PRISMA guidelines.
The Polyglot Search Translator is a tool for translating search strings from Medline via Ovid or PubMed across multiple databases (CINAHL, Cochrane, Embase, Medline, PsycINFO, PubMed, Scopus, and Web of Science). It has been developed by the Institute for Evidence-Based Healthcare at Bond University.
Note! Whilst Polyglot translates the syntax for controlled vocabulary terms, it can not automatically map the terms across databases (e.g. MeSH terms to Emtree terms). You need to do this manually.
Medline Transpose can help you convert the search syntax between PubMed and Medline via Ovid interfaces. The tool has been developed by the College of Physicians and Surgeons of British Columbia (CPSBC) and the Collaboration for Leadership in Applied Health Research and Care South West Peninsula (PenCLAHRC).
This translation tool developed by Ovid helps translate a PubMed search strategy to a Medline via Ovid or Embase via Ovid search strategy.
As each database has its own indexing system, you need to identify the controlled vocabulary terms for each database separately.
These are the controlled vocabulary terms for Concept 1 for some of our UTAS health databases (note the slightly different spelling):
| MeSH Terms | PsycInfo Thesaurus | CINAHL Headings | Emtree Terms |
|---|---|---|---|
|
Dementia Alzheimer disease |
Dementia Alzheimer's disease |
Dementia Alzheimer's disease |
Dementia Alzheimer disease |
Also, note how the syntax between different databases varies, even if they use the same controlled vocabulary; e.g. demonstrated for the three databases that use MeSH as the controlled vocabulary:
| PubMed | Ovid | Cochrane |
|---|---|---|
|
Dementia [mh] Alzheimer disease [mh] |
exp dementia/ exp Alzheimer disease/ |
MeSH descriptor: [Dementia] explode all trees MeSH descriptor: [Alzheimer Disease] explode all trees |
Not all databases offer users to customise the search fields as freely as Ovid. Simply try to keep the search fields as consistent as possible. This table lists similar options in UTAS Health databases:
| Medline via PubMed | dementia [tiab] |
|---|---|
| Medline via Ovid | dementia.ab,kf,ti. |
| Embase | dementia.ab,kw,ti. |
| PsycINFO | dementia.ab,id,ti. |
| Cochrane | dementia:ti,ab,kw |
| CINAHL | TI dementia OR AB dementia |
| Web of Science | TOPIC: (dementia) |
| Scopus | TITLE-ABS-KEY ( dementia ) |
Some databases offer a wider range of proximity operators and wildcards than others; plus the function of the symbols used varies between the databases. It is best to visit the Search Help menu within the relevant database or see
Here are a few examples for the example search to illustrate the difference of symbols and meaning.
| Ovid databases | behavio?r.ab,kf,ti. |
? stands for zero or one character within a word |
|---|---|---|
| Cochrane | behavi*r:ti,ab,kw |
* is used to match multiple characters within a word |
| CINAHL | behavio#r.ab,kw,ti. | # finds all citations of the word that appear with or without the extra character finds behavior and behaviour |
| Web of Science | TOPIC: (behavio$r) |
$ useful for finding British and American spellings of same word |
| Scopus | Scopus finds common American/British English variant spellings automatically | |
| Ovid databases | animal adj2 therapy.ab,kf,ti. | animal and therapy need to be within 2 words of each other: one or no word between them |
|---|---|---|
| Medline via PubMed | "animal therapy"[tiab:~2] | Finds the terms when maximum number of words between them is two |
| Cochrane | animal near/2 therapy:ti,ab,kw | Finds the terms when maximum number of words between them is two |
| CINAHL | (TI animal N2 therapy) OR (AB animal N2 therapy) | N2 finds the words if they are within two words of one another regardless of the order in which they appear |
| Web of Science | TOPIC: (animal NEAR/2 therapy) | NEAR/2 maximum 2 words separate the terms |
| Scopus | TITLE-ABS-KEY ( animal W/2 therapy ) | W/2 finds the terms when they are within 2 words of one another |
