This page provides the search syntax for the BioMedSearch.com website.
The basic structure for the syntax query on BioMedSearch is: term [FIELD]

A query is broken up into terms and Boolean operators. There are two types of terms: Single Terms and Phrases.
A Single Term is a single word such as "test" or "hello."
Multiple terms can also be combined using parentheses.
A Phrase is a group of words surrounded by double quotes such as "hello world."

This would search the system database for user term based on common fields including PMID, author name, article title or journal title.

Quick search lists the most common search fields. You can search for a word or a simple phrase or document number in any of the listed fields. You can search in more than one field at a time. You can also use wildcards to enhance your searches in quick search (see wildcards for tips and examples for searching with wildcards). Boolean operators and nesting are not allowed in quick search. Quick search also has additional features like word stemming, sort order and date range to further enhance your search.

Expert search helps you create complex queries to search multiple fields using field abbreviations. You can also include Boolean operators, nesting and wildcards in your expert search query. To add value to your searches, BioMedSearch incorporates proximity searching and search term weighting features in expert search. Word stemming, sort order and date range options are available to further enhance your search.

You can select to sort the documents in your results list either chronologically or according to their relevancy. If you select chronological sort order, documents in the results list would be arranged chronologically, with most recently published documents on the top of the list. You can also select to sort the documents in the results list according to their relevancy. Relevancy sorting is based on a "relevancy score" assigned to each document. Relevancy score is based on frequency and positioning of keyword(s) in the document. Relevancy score ranges from 0 to 1000. Documents with higher relevancy score would be placed at the top of the list.

Boolean operators allow terms to be combined through logic operators. BioMedSearch supports AND, "+", OR, NOT and "-" as Boolean operators (Note: Boolean operators can be lower case as well).
The AND operator is the default conjunction operator. This means that if there is no Boolean operator between two terms, the AND operator is used. The AND operator links two terms and finds a matching document if both terms exist anywhere in a document. This is equivalent to an intersection using sets. The symbol && can be used in place of the word AND.
To search for document that contain all the words water, borne, disease use the query:
water borne disease
or
water AND borne AND disease
This also works with fielded search:
water[TIAB] AND borne[TIAB] AND disease[TIAB]
Note, that the above query IS NOT the same as:
water AND borne AND disease[TIAB]
The above query would search for water and borne in any of the fields, and only restrict the word disease to the Title/Abstract field.

You can enclose search terms and their operators in parentheses or brackets to specify the order in which they should be processed. Information within parentheses is read first and then information outside parentheses. If there are more than one set of parentheses, the innermost set of parentheses would be read first, then the next and so on until the whole query is interpreted. The order of precedence for parenthesis and Boolean operators is:

1.     Parentheses

2.     NOT

3.     AND

4.     OR

Nested query	How it is interpreted (following order of precedence)
Water and borne or disease	(Water and borne) or disease
(water or borne and resistant) and disease	(water or (borne and resistant)) and disease

Proximity searching helps you to specify how near/distant you want your search terms to be. You can specify the distance or nearness of the terms searched as whole numbers. The proximity operator in BioMedSearch is "~". The proximity operator should be followed by a whole number indicating the proximity of the search terms. For example, "~10" means within ten words of each other. Note: Ensure that your keywords are enclosed in double-quotation marks, and there is no space left between the end-quotation mark and the proximity operator.

Query	Results list would have
"Enzyme peptide"~3	Documents with both enzyme and peptide, where both are within 3 words of each other.
"fermentation bacteria milk"~5	Documents where the words fermentation, bacteria and milk, are present within 5 words of each other.

BioMedSearch supports fuzzy searches based on the Levenshtein Distance, or Edit Distance algorithm. To do a fuzzy search use the tilde, "~", symbol at the end of a single word term.

Query	Results list would have
roam~[ti]	Documents with the word "foam" or "roams" in the title field.

BioMedSearch allows date range searches using the appropriate date field, and a colon as a date separator. The following search will result in documents that have a Published Date from January 1, 1999 to March 31, 1999:

1999/01/01:1999/03/31[DP]

Dates can also be truncated at the day and month level, meaning that those parts of the date are not required.  When omitted, logical values are assumed.  The following search will result in the same documents as those in the above example:

1999/01:1999/03[DP]

The following syntax will also work. This search will search for all documents with a Published Date in the year 2008:

2008[DP]

This is logically equivalent to:

2008/01/01:2008/12/31[DP]

BioMedSearch allows Text range searches, similar to the Date Ranges described above. Instead of using dates, text can be used, and the search will return results that exist between the two terms specified (inclusive).

Query	Results list would have
(blood:bloody)[ti]	Articles with terms alphabetically between blood and bloody in the title. For example, bloodless, bloodstream, bloodworm, etc.

Truncation or Wildcard searching allows you to retrieve documents containing variations of a search term. Wildcard symbols can be used to replace a single letter or a part of a word, or one or more numbers.

We can use two wildcards: ? to replace exactly one character or number. * to replace zero or multiple characters or numbers.

Query	Results list would have
Analy?e	Analyse and Analyze
Sul*ur	Sulphur and Sulfur
Harbo*r	Harbor and harbour

BioMedSearch provides the relevance level of matching documents based on the terms found. To boost a term use the caret, "^", symbol with a boost factor (a number) at the end of the term you are searching. The higher the boost factor, the more relevant the term will be.

Boosting allows you to control the relevance of a document by boosting its term. For example, if you are searching for water disease and you want the term disease to be more relevant, boost it using the ^ symbol along with the boost factor next to the term. You would type:

water disease^4

This can also be done in fielded searches:

water^4[TIAB] disease^2[TIAB] smith[AU]

By default, the boost factor is 1. Although the boost factor must be positive, it can be less than 1 (e.g. 0.2).

BioMedSearch supports fielded data. When performing a search you may either specify a field, or identify no field, in which case the terms will be searched against all indexed fields.

You can execute field searches by typing in the term(s) to be searched, followed by the field name enclosed in brackets.

As an example, let's assume you want to search for the word water in the Title/Abstract field:

water[TIAB]

If you wanted to search for the word water, regardless of which field it was in:

Water

If you wanted to search for multiple words in the same field:

water[TIAB] disease[TIAB]

The following query will result in the word water being searched for in all fields, and the word disease being limited to the Title/Abstract field.

water disease[TIAB]

If you wanted to search for both terms water and disease in the Title/Abstract field:

(water AND disease)[TIAB]

or

(water disease)[TIAB]

To search for water or disease in the Title/Abstract:

(water OR disease)[TIAB]

Multiple fields can also be searched.  The following query will search for the word disease in the Title/Abstract field and the word smith in the Author field.

disease[TIAB] AND smith[AU]

Whenever special characters are used in expressions, there is a need to provide an escaping mechanism so that the special characters themselves can be used in a normal fashion. BioMedSearch uses a backslash to escape special characters within terms. The list of escapable characters is:

* *  +   -   !   (   )   :   ^   ]   {   }   ~   *   ?

To escape these character use the \ before the character. For example to search for (1+1):2 use the query:

(1+1)\:2

Data Element	Description
water	Find all documents containing the word 'water' in any field.
water[AB]	Find all documents containing the word 'water' in only the abstract.
Water AND disease	Find all documents containing both the word 'water' and the word 'disease' in any fields (e.g., title, abstract, or specification/description). The two words may be in different fields.
water[AB] AND disease	Find all documents containing the word 'water' in the abstract, and the word 'disease' in any field (e.g.,title, abstract, or specification/description).
water[AB] AND 2000/12/14:2005/12/31[DP]	Find all documents containing the word 'water' in the abstract which have a Publication Date between Dec 14, 2000 and Dec 31, 2005.
water[TI] NOT disease	Find all documents containing the word 'water' in the title, but do not include any documents which have the word 'disease' in any field (e.g., title, abstract, or specification/description).
(water OR disease) AND (borne OR resistant)	Find all documents that contain either the word 'water' or the word 'disease', and which also contain either the word 'borne' or the word 'resistant.' Note that without the parenthesis this query would be interpreted in an entirely different manner.
[with word stemming on] electroplate	Find all forms of the word 'electroplate', including 'electroplated', 'electroplating', and 'electroplater'.
"Water disease"~5	Find all documents containing the word 'water' within 5 words of 'disease', in any fields (e.g., title, abstract, or body). The "5" may be replaced with any whole number.
cat^5 OR disease	Water is 5 times more important to the relevancy of documents than disease. Find all documents containing the word 'water' or 'disease' but, all other things being equal, rank the documents containing water higher. The "5" may be replaced with any whole number.
electron*	Find all documents containing words starting with electron like electron, electrons, electronic, electronics, etc.
su?	Find all documents containing words that has only one character after 'su' like sub, sun, sum, etc.

List of Search Fields