MEDLINE Searching Skills:Finding the best evidence

Learning Objectives

• Identifying search concepts that apply to your clinical case

• Strategies to limit a search to relevant information

• Strategies to find the best evidence

1. Go to http://medsearch.lib.umich.edu OR link from the Clinical homepage.....

2. Log in

1. Go to http://medsearch.lib.umich.edu OR link from the Clinical homepage.....

Click on the link to MEDLINE

Clinical question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

1. Enter a search term that represents an aspect from your clinical question

Clinical question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

2. Your search term will “map” to one or more official search terms called MEDICAL SUBJECT HEADINGS (MeSH) terms

1. Enter a search term that represents an aspect from your clinical question

Clinical question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

2. Your search term will “map” to one or more official search terms called MEDICAL SUBJECT HEADINGS (MeSH) terms

1. Enter a search term that represents an aspect from your clinical question

Clinical question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

1. The official MeSH term for appendectomy is.... APPENDECTOMY

2. Why are MeSH terms effective/efficient when searching MEDLINE?

MeSH controlled vocabulary is a distinctive feature of MEDLINE used to index articles.

It imposes uniformity and consistency to the indexing of biomedical literature.

Example: the MeSH term “Neoplasm” finds articles on neoplasms and tumors and cancer…..

1. The official MeSH term for appendectomy is.... APPENDECTOMY

2. Why are MeSH terms effective/efficient when searching MEDLINE?

MeSH controlled vocabulary is a distinctive feature of MEDLINE used to index articles.

It imposes uniformity and consistency to the indexing of biomedical literature.

Example: MeSH term “Neoplasm” finds articles on neoplasms and tumors and cancer…..

3. Question: What does EXPLODE mean? ......

1. The official MeSH term for appendectomy is.... APPENDECTOMY

Answer: The Explode feature allows your search to find literature on more specific MeSH terms.

For example, when you “explode” the MeSH term “Mastectomy”, you’ll pick up articles about the concept of Mastectomy in general, but you’ll also pick up articles on the more specific concepts of…..

Mastectomy, Radical    

Mastectomy, Segmental    

Mastectomy, Simple    

Mastectomy, Subcutaneous

“Exploding” can help you do a more comprehensive search

Answer: The Explode feature allows your search to find literature on more specific MeSH terms.

For example, when you “explode” the MeSH term “Mastectomy”, you’ll pick up articles about the concept of Mastectomy in general, but you’ll also pick up articles on the more specific concepts of…..

Mastectomy, Radical    

Mastectomy, Segmental    

Mastectomy, Simple    

Mastectomy, Subcutaneous

“Exploding” can help you do a more comprehensive search

Question: What does FOCUS mean? ......

Question: What does the FOCUS feature do? ......

Answer: By choosing the FOCUS feature, you want “Appendectomy” to be considered a major topic of the articles that your search retrieves.

Search Tip #1: Just remember that by using the FOCUS feature, you’re going to pick up fewer articles.... So if you’re not sure if there is a lot of information on your topic, you might not want to focus the search term.

Search Tip #2: If you choose to use the FOCUS feature, do not focus all of your search terms – if you focus too many search terms, you’ll lose many potentially relevant articles.

Question: What does the FOCUS feature do? ......

Answer: By choosing the FOCUS feature, you want “Appendectomy” to be considered a major topic of the articles that your search retrieves.

Search Tip #1: Just remember that by using the FOCUS feature, you’re going to pick up fewer articles.... So if you’re not sure if there is a lot of information on your topic, you might not want to focus the search term.

Search Tip #2: If you choose to use the FOCUS feature, do not focus all of your search terms – if you focus too many search terms, you’ll lose many potentially relevant articles.

Subheadings help you narrow your search to specific aspects applied to a MeSH term.

Search Tip: Only use subheadings if it specifically applies to your search question. Otherwise, subheadings can narrow your search too much….

Subheadings help you narrow your search to specific aspects applied to a MeSH term.

Search Tip: Only use subheadings if it specifically applies to your search question. Otherwise, subheadings can narrow your search too much….

It’s actually a good thing to start a search with a large number of search results if you expect to combine it with other search terms…..

Clinical question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

Clinical question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

The official MeSH term for postoperative wound infection is.... SURGICAL WOUND INFECTION

The official MeSH term for postoperative wound infection is.... SURGICAL WOUND INFECTION

What happens when you click on the SCOPE button?

Why use a SCOPE NOTE?

Provides additional information about MeSH search terms

- when the term was first used

- the context (or definition) of the term in the database

- “used for” terms and “see also” terms

- other relevant information and search tips

Why use a SCOPE NOTE?

Provides additional information about MeSH search terms

- when the term was first used

- the context (or definition) of the term in the database

- “used for” terms and “see also” terms

- other relevant information and search tips

Click to go back….Click to go back….

If you’re not satisfied with the suggested (i.e. mapped) MeSH term, you can select the last option on the list to do a Keyword search.

Search Tip: It’s still a good idea to include the suggested MeSH term as well as the Keyword….just to be sure!

If you’re not satisfied with the suggested (i.e. mapped) MeSH term, you can select the last option on the list to do a Keyword search.

Search Tip: It’s still a good idea to include the suggested MeSH term as well as the Keyword….just to be sure!

Clinical Question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

Clinical Question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

Clinical Question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

Clinical Question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

1. The phrase “perioperative antibiotics” maps to this list of MeSH terms. It’s up to you to choose the appropriate MeSH terms.

If none of them apply, use the keyword at the bottom of the list.

2. In this case, 2 MeSH terms apply….

You can select more than one MeSH term by combining them (using “AND”) or choosing either terms (using “OR”)

1. The phrase “perioperative antibiotics” maps to this list of MeSH terms. It’s up to you to choose the appropriate MeSH terms.

If none of them apply, use the keyword at the bottom of the list.

2. In this case, 2 MeSH terms apply….

You can select more than one MeSH term by combining them (using “AND”) or choosing either terms (using “OR”)

1. The phrase “perioperative antibiotics” maps to this list of MeSH terms. It’s up to you to choose the appropriate MeSH terms.

If none of them apply, use the keyword at the bottom of the list.

Combining your search terms….

Combining your search terms….

Question: What is the point of placing each search concept on a separate search line?

Answer: It allows you the freedom of making various combinations of search terms…..

Combining your search terms….

Question: What is the point of placing each search concept on a separate search line?

Answer: It allows you the freedom of making various combinations of search terms…..

SEARCH LIMITS: Help to narrow your retrieval to more relevant information

Limits also help when you have too many articles and not enough time!

SEARCH LIMITS: Help to narrow your retrieval to more relevant information

Limits also help when you have too many articles and not enough time!

Some common limits are on this main page. But to see some more relevant limits click on the “More Limits” link…..

Clinical Question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

Limiting a search by age group, an important patient characteristic, can be very useful.

Search Tip: You can limit to more than one age group by holding the CTRL or APPLE key when choosing the age limits.

Clinical Question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

Limiting a search by age group, an important patient characteristic, can be very useful.

Search Tip: You can limit to more than one age group by holding the CTRL or APPLE key when choosing the age limits.

From your 61 results....

From your 61 results....

...but there are strategies to narrow down further to best evidence results......

Strategies to find best evidence

1. Limit to “EBM Reviews”

Before you find “best evidence”...

• It’s important that you identify the category in which your clinical question belongs...

– Is it a question of THERAPY?– Is it a question of DIAGNOSIS?– Is it a question of PROGNOSIS?– Is it a question of ETIOLOGY/HARM?

Clinical question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

In which category does this question belong?.....

Clinical question: Do perioperative antibiotics prevent postoperative wound infections in adults who have undergone appendectomy?

This is a question of THERAPY.

Limiting to EBM Reviews allows you to find Cochrane systematic reviews and RCTs included in Cochrane systematic reviews......

Limiting to EBM Reviews allows you to find Cochrane systematic reviews and RCTs included in Cochrane systematic reviews......

Important: Cochrane systematic reviews address questions of THERAPY only......

Limiting to EBM Reviews allows you to find Cochrane systematic reviews and RCTs included in Cochrane systematic reviews......

Important: Cochrane systematic reviews address questions of THERAPY only......

If you see a citation with an EBM Topic Review link, it will take you directly to the full text of a Cochrane systematic review that includes the listed RCT.

Strategies to find best evidence

2. Using “Clinical Queries” limit

Go to More Limits

Limiting to Clinical Queries will restrict search retrieval to clinically sound studies identified by the category of question.

The emphasis may be:

• Sensitive (i.e., most relevant articles but probably some less relevant ones)

• Specific (i.e., mostly relevant articles but probably omitting a few), or

• Optimized (i.e., the combination of terms that optimizes the trade-off between sensitivity and specificity)

Search Tip: Using OPTIMIZED is recommended

From the “Therapy (Optimized)” results…