HOW TO USE OVID’S MEDLINE
Functions on the Main Search
Page
Functions on the Icon Bar
Basic Functions and Searching Strategies for Ovid
Searching One Topic Alone
Limiters and the Results of Searching
The Limiter’s Page
Displaying Results and Understanding
Citations
Using the Citation Manager
Saving, Printing, or Emailing Articles
Finding Full Text Articles
Listed in NovaCat
Finding Full Text Articles Not Listed in
NovaCat
Accessing Multiple
Databases
Removing Duplicates
Two- or Three-Term Searches:
Introduction to Boolean Logic
The AND Operator: Creating Intersection of Sets
The OR Operator: Creating Union of Sets
The NOT Operator: Excluding Articles
ACCESS TO THE DATABASE
To access MEDLINE from the Health Professions Division’s Library’s homepage, click on the words “MEDLINE (OVID) in the left panel. See the arrow in the image below.
You will then be asked to register. Type your last name in the top box and your NSU ID number in the bottom box. To end the registration process, click on the “SUBMIT” button located below.
To continue, click on “Yes” in the box that appears superimposed on your screen.
MEDLINE
To gain access to any of the Ovid databases, click on its title. Notice in the illustration below that MEDLINE has numerous parts, each encompassing a different time period. The third MEDLINE section on the list (1) constitutes the most current group of articles. These articles were published in the last eight-year period. MEDLINE In-Process & Other Non-Indexed Citations, seen just above (2), is a list of articles even more recently published but not yet completely processed by the indexers at the National Library of Medicine. The last section of MEDLINE (3), at the very bottom of the list, covers the period, 1966 to the present. It is the most comprehensive database in MEDLINE, but it does not list the articles in MEDLINE IN-Process. To search both MEDLINE and MEDLINE In-Process at the same time, you will need to select MEDLINE In-Process & Other Non-Indexed Citations and Medline (4). Ovid also offers Books@Ovid (5) which are reference books in their entirety. Complete “Full-Text” journal articles are also available throughout the various sections.
(4)
RESTARTING OVID AFTER “TIMING-OUT”
If you have been forced out of the Ovid databases as a result of “timing out” or exceeding the limit of “idle time,” as it is called, you will see a screen part of which is shown below. To restart Ovid, you do not have to register again. Simply click on the “Start Ovid” button as shown below.
THE MAIN SEARCH PAGE
FUNCTIONS ON THE MAIN SEARCH PAGE
The “Main Search Page” displayed below includes (looking from top to bottom) the following items:
1. The dates encompassed by the current database;
2. The “Icon Bar” with access points to and features of the database;
3. The “Search History” box in which you can keep a record of the searches;
4. The “Query Box” into which you enter your search terms; and
5. (5a) A partial list of “Limiters” or filters. There are many other limiters on a separate screen found under the “Limit” icon: an arrow in a target (5b).
FUNCTIONS ON THE ICON BAR
Using the Icon Bar’s access points to the database seen above, you can search by
1. AUTHOR. You can do searches by the name of the author, e.g. “Ammons
WF” (Note: do not type a comma between last and first names).
2. TITLE. You can also do searches on the title of the article, e.g. “clinical spectrum of desquamative…” (You do not need to enter the entire title; just enough to distinguish it from other article titles which may be similar).
3. JOURNAL. You can limit your search to a specific journal, e.g. “New England Journal of Medicine.”
4. SEARCH FIELDS. You can search a particular field in the records, e.g. “author,” “volume number,” “molecule sequence” or “journal word.” The latter can be used to find “continuations” of which the HPD Library has many (continuations are a series of review articles on one major topic published in book form).
5. TOOLS. You can use various tools, e.g. “permuted index,” (a list of terms in which a specific word is included).
6. COMBINE. You can combine two or more searches by using Boolean operators (explained in great detail later).
7. LIMIT. You can set limits on searches with filters not available from the Main Search Page.
8. BASIC. You can switch to basic searching (not advisable because basic searching does not permit the use of all of Ovid’s many powerful features).
9. CHANGE DATABASE. You can switch to another database in the Ovid group and redo the search without re-entering your original search terms.
10. LOGOFF. You can end the search session and leave Ovid. This is highly recommended when you have completed your research so as to allow access to the databases for other users.
Although the examples
provided above show quotation marks around them, this is for grammatical
purposes. Do not use these quotation marks when you actually perform your own
searches and use these features.
BASIC FUNCTIONS AND SEARCHING STRATEGIES FOR OVID
SEARCHING ON ONE TOPIC ALONE
Enter
a term into the Query Box, e.g. “Diabetes Mellitus.” Then click on the rounded “Perform Search” button to the right
side of the Query Box. See the example below.
In
the illustration below, you will see the “Mapping Display” screen (to be
discussed in greater detail later in the section, “Using the Mapping Function”)
with the topic already selected. Simply click in the “Focus” box to the right of
the image. “Focusing” will be explained thoroughly later in the section
entitled, “Using the Mapping Function.” The last item is the ball under
“Scope.” It provides a definition, called the “Scope Note,” of the search term.
The
next screen is called the “Subheading Display.” For this particular search,
select the articles found by clicking in the box entitled “Include All
Subheadings.” More information about subheadings will be provided in the
section called, “Limiting by Subject Headings.”
LIMITERS AND THE RESULTS OF SEARCHING
After you have performed your search and have used the functions on both the “Mapping Display” and “Subheading Display” pages, you will see the search results in the Search History box, a mechanism by which you can keep a record of the searches you performed and the results of each search (1). In the example shown below, the numerals to the right of the search term represent the number of articles retrieved, the “Results” of the search or “hits.” Usually, as is the case in the illustration shown on the next page, you will obtain far too many hits with which to work effectively. You can reduce that number by using one or more of the limiters found below the Query Box, e.g. “English” (2) and “Publication Year” (3). In all cases, you click on the boxes to the left of the limiters to select them. If you choose the two Limiters just mentioned, this means that only those records will be retrieved which are in English and were published between 2000 and 2003. To select dates of publication, click on the down arrows in the boxes to the right of the publication year and highlight the years you desire. You can also limit the search results to one year by placing the same year in both boxes, e.g. “2003-2003.”
In the example below, the result of imposing two of the indicated Limiters (English and publication year) is shown (4). As you can see, the change is significant: more than half of the articles retrieved in the prior search have been excluded. You can now look at the articles retrieved by clicking on the “Display” button to the far right of the Search History box (5).
THE LIMITERS’ PAGE
[Table of Contents]
DISPLAYING RESULTS AND UNDERSTANDING CITATIONS
As
you have seen, after you have performed and limited your search, you click on
the word “Display” that is located on the right side of the Search History box.
The results of the search will then be listed in order of currency in groups of
ten “citations” per page. A “citation” includes the name(s) of the author(s),
the title of the article, the name of the journal, the volume number and the
issue number (shown in parentheses), the page numbers, and the date of
publication. Carefully study the titles of the articles, because they are
usually very descriptive of the contents. Naturally, you will select only those
which match your research needs. You select articles by placing a checkmark in
the boxes to the left of the article titles.
In
the illustration on display above, you can see publications of three types. The
types are indicated in the brackets shown to the right, just after the article
titles: (1) Citation no. 5 (arrow no. 1) is called a “Journal Article.” This is
a report on an experiment, a study, or other first line medical investigation.
It represents primary research. (2) Citation no. 6 (arrow no. 2) is a “Letter”
to the editor of the journal. (3) Citation no. 7 (arrow no. 3) is a “Review
Article,” one in which the authors describe the medical literature on a given
subject published during a recent six-month period. A review is secondary
research. The number of articles cited by the authors of the review is shown in
the second set of brackets. In the case of citation no. 7 (arrow number 3), 141
articles were included in the review.
After reading through the first list of titles, go to the next group of citations by clicking on the purple bar marked “Next Citations.” The “Next Citations” bar can be found at the top and bottom of every screen that lists citations.
Continue to go through the screens until you are sure that you have selected as many of the articles as will be sufficient for your research needs.
USING THE CITATION MANAGER
When
you are done with the selection process, you will need to retrieve the articles
you have decided to keep. To do so, scroll to the very bottom of the screen on
which you find yourself currently. As shown below, you will find the “Citation
Manager” box there. This box can be found at the bottom of any screen that
presents a list of articles for your inspection.
On the left side of the Citation Manager, you will find a panel marked “Citations” (1). If you have selected more than one article, click on the radio button marked “Selected Citations” (2). This is the default setting. In the next panel, the “Fields” panel, choose the format in which you want the articles to be printed out. The default setting is “Citation + Abstract” (3). This latter format usually provides all of the information you require to examine the contents of the article. However, if you are not sure of the terms that you need in order to do a really precise search, you can select the third option on the list which includes not only the citation and abstract, but also the “Subject Headings,” that is, the main topics discussed by the authors (4). The latter option generates a list of standardized medical terms called “controlled vocabulary.” The controlled vocabulary is used by the indexers of the database who, in order to make the published material available to searchers, need to catalog the articles under medical terms agreed upon by the entire international medical community. Often, the Subject Headings contain alternate, more exact terms that you may want to use to further explore your topic. In most of the search situations in which you will find yourself, you may disregard the next panel in the Citation Manager. However, if you wish to keep a copy of your entire search process for later inspection, click in the box to the left of the text “Include Search History” (5).
SAVING, PRINTING, OR EMAILING ARTICLES
To print or save articles, click on the “Display” bar located in the “Action” panel. This action changes the format in which the articles are normally presented on the list, namely the “Citation” format, to the format of your choice, e.g. “Citation + Abstract” or any of the others. Then, to keep the articles you have retrieved, use the print function offered by the browser that you are using. In the illustration below, showing the browser Netscape Navigator, the arrow is pointing to the print function.
In addition to the “Display” function just described, the “Action” panel contains other options for saving the search results. The “Email” function enables you to send the citations to your email account. You can then print them in the computer laboratory located near the entrance to the HPD Library or at home or on any computer to which you have access. The “Save” function permits you to download the citations to a floppy disk that you can later use to view and edit the information in your word processor at home.
[Table of Contents]
USING THE MAPPING FUNCTION
As
you have seen earlier in the section, SEARCHING ON ONE TOPIC ALONE, after you have
entered a search term and pressed the “Perform Search” button, you will be
taken to the “Mapping Display” screen. (1) If you click in the “Focus” box, the
hits will be limited to articles in which your search term is the main topic.
(2) On the other hand, if you click in the “Explode” box, you will retrieve
articles not only with the search term, but also any articles that might be
listed under that term in the National Library of Medicine’s hierarchy
of medical terms. You can view the official medical terms and the hierarchy in
the National Library of Medicine’s annual publication entitled Medical Subject Headings. Multiple
copies can be found in the HPD library. The structure used to arrange the
medical terms constitutes a list of related medical topics and is called the
“Tree Display.” It can be very helpful,
especially when you need to find how medical topics are related and what is the
official medical terminology used by most medical indexers.
To
illustrate exploding on a term, here is an example. If you exploded on the term
“Eating Disorders,” you would retrieve articles on that subject, and you would
also retrieve information about the various eating disorders themselves (all
listed in the “Tree Display” under “Eating Disorders), namely: “Anorexia,”
“Anorexia Nervosa,” “Bulimia,” “Coprophagia,” “Hyperphagia,” and “Pica.”
Exploding
on terms is commonly used if there are too few hits resulting from a given
search. But because you will frequently get far too many hits, too many to work
with conveniently, you will want to limit your search to the most relevant
information. Thus, you will need to employ the “Focus” function. Then, as is
customary in Ovid databases, you will need to click on the rounded “Continue”
button to execute the search.
[Table of Contents]
LIMITING BY SUBJECT HEADINGS
In most Ovid databases, another method of limiting one-topic searches is to make use of “Subheadings.” The latter are normally displayed on the screen that you see after you have entered a search term in the Query Box and clicked on the “Continue” button. You come to the “Mapping Display” page, where, after choosing to focus, you click the “Continue” button once again.
You are then brought to the “Subheading Display” page. Here you can select one or more of the “Subheadings.”
Subheadings are the focus of or direction taken by the researchers in their work. For instance, as you see in the illustration on page 14, the next page, some researchers may concentrate on symptoms for a precise (1) diagnosis of a particular condition. Others may be more interested in the (2) therapy required to help the patient. Yet others might want to find ways in which to (3) prevent and control the condition under investigation. There are more than a dozen focus points for many of the topics you will be researching. In the picture below, several subheadings have been selected. The search engine will now ignore all articles listed under the other subheadings and focus on these three alone. As you will notice by the number in parentheses to the right of each subheading, choosing one or several of the subheadings will substantially reduce the number of overall hits which, in this case, exceed three thousand (See the section LIMITERS AND THE RESULTS OF SEARCHING above). Moreover, by making use of the subheadings, your search results should be much more focused and pertinent to your research requirements.
Below, you can see in the Query Box on the Main Search Page, the subheadings selected from the Subheading list.
FINDING FULL TEXT ARTICLES
FINDING FULL TEXT ARTICLES LISTED IN NOVACAT
