Friday, October 26, 2012

How the PICO search works

So far the PICO search has been one of the most heavily praised features on the new Trip.  But, we received the following comment:

I noticed my search was translated as follows: 8 results for "(title:ischaemic stroke)(title:CT perfusion scan)(non CT perfusion)", by relevance

Does this mean that TRIP searches for search terms entered in the PICO search interface only in the titles of articles? 

If so, I would not feel confident that I had not missed out on other pertinent papers....


This is a really important point, how does PICO search work?

At the heart of the PICO search is something called contingency searching.  With the normal Trip search you get all the results that match your search terms but with the PICO search we aim to just show a limited number of highly focused results.  To achieve this our first search is for all the PICO elements as title only searches.  If there are too few results we then make the final search term a 'title and text' search and repeat the search and if that too has too few results we make the penultimate term a 'title and text' and we repeat that until we get a manageable number of results.  All these repeated searches are done in the background; from a user's perspective it's a single search. 

So, in response to the last point raised by the user, it's not an exhaustive search and should not really be used for a timely 'gather all' search. It's designed to help users, who are in a rush, get a really manageable set of results to help answer their clinical query.  It does that rather well.

A 'screengrab' showing the PICO search is below (click to make larger). We've also made a screencast to demonstrate PICO in action - click here to view that.

2 comments:

aliencamel said...

I just did a PICO search using the terms anorexia nervosa adolescents, antidepressants vs placebo and suicide.
The first paper retrieved was on COPD with none of the above terms. Why does this happen?
Thanks
MS

Jon Brassey said...

You're right, it's a rubbish result! If you do a non-pico search for http://www.tripdatabase.com/search?categoryid=&criteria=anorexia+nervosa++antidepressants+suicide you get better results.

I'll ask our techie to investigate!

Best wishes

jon

Jon Brassey
Trip Database
www.tripdatabase.com