Trip Database Blog

Liberating the literature

Eight new publications added to Trip

Trip is loved because it’s easy to use and allows users to quickly identify high-quality evidence. A clear prerequisite is to have lots of high-quality evidence! As such we’re always on the look out for such content and this month has been a bumper month – with the inclusion of eight new publishers. Many of these were identified by reviewing the latest CADTH Grey Matters tool.

And, one request for you, if you know of any sites which should be included in Trip, please let us know (via comments or email

Below is the list of newly added content:

  1. Palliative Care Evidence Review Service (Rapid reviews)
  2. EUnetHTA (HTA)
  3. SickKids Reports (Reviews)
  4. SickKids Supportive Care Guidelines (Guidelines)
  5. Washington Health Care Authority (HTA)
  6. Health Information and Quality Authority (HTA)
  7. European Society of Endocrinology (Guidelines)
  8. Pediatric Endocrine Society (Guidelines)

NOTE: These have only just been uploaded and will take up to 72 hours to be indexed and searchable!

Answering clinical questions – positioning survey

Last week I highlighted our plans for a Q&A system to harness the combined intelligence of the Trip community.  In that, I identified two main challenges:

  • Technology – to make the system work
  • User acceptance – how can we explain the system in a way that users can relate to and make sense of (and ultimately use)?

The latter challenge seems much harder and to help us we’ve created a brief survey which we’re hoping as many of you as possible will complete. It should take around 2 minutes – so hopefully time is not a barrier to use.  To undertake the survey please CLICK HERE.

To repeat, please take the survey (CLICK HERE) – your opinion really does count.

Answering clinical questions

Trip started as a service to support clinical question answering. Since then the site has changed dramatically but we still see clinical question answering as the main drive and focus.

But what happens if Trip lets a user down? In other words the user has a question, uses Trip and can’t find an answer! In the last two days we’ve received two questions from users:

  • EBM causation of intervertebral disc herniation?
  • Dexmedetomidine and brain protection: fact or fiction?

Now, I dare say the answer is somewhere in Trip and I imagine that terms like ‘brain protection’ may need clarifying. But, at the heart of it – for whatever reason – the users are struggling.

So, we return to the notion of using Trip’s community to help answer them. There is no doubt that there are people, who are registered on Trip, who will know about disc herniation and dexmedetomidine. They may well be able to easily answer these questions. So, why not send the Qs to those most likely to know the answer?

Well, you may have guessed it, but that’s the plan, to create a community Q&A system. There are a number of challenges, for instance:

  • Technology: linking the Q to those most likely to be able to answer them. We’ve engaged with an external company to work on this problem and we’re feeling very confident that good progress will be made.
  • User engagement: we know many people love Trip and we know we have many registered users (over 100,000) but will a large enough proportion be willing to help their fellow users? We’re thinking yes! But we need to communicate really well to explain what we’re doing and reduce any barriers to community involvement.

No timeline, but now we’re committed I’m hoping we can motor!


New search, new server

We’ve just upgraded to a new and more powerful server system – lots of extra memory and speed.

As part of the new system we’ve also improved two other things:

  • Upgraded the version of our search engine technology to the latest version. This has improved many things including my own bugbear – duplicate terms in the title boosting the result. In the old version if a document had the search term(s) mentioned twice in the title it would get a large boost. It didn’t happen often but it was annoying! But it appears that’s been fixed.
  • Improved our indexing of PubMed.  Previously we’d been grabbing all the content from PubMed via eUtilities and we only realised recently that this included all the additional meta-data including things like related articles and cited articles data.  This created false positive results.  Our new indexing will now only grab content from the abstract.  This means results counts are both reduced and more accurate (less noise).

We’ve tested it extensively but if you spot anything strange please let us know.


NOTE: I can see the new server but it might take 24 hours for the internet’s address book to point at the new version. If the ‘Evidence Maps’ link at the top of the page is highlighted yellow, you’re still pointing at the old version!

Include all of PubMed in Trip?

Currently Trip includes a sub-set of PubMed. This includes all RCTs and systematic reviews and the content of around 500 ‘core’ journals. In total this represents around 10-15% of all the PubMed content. Putting it another way we have around 3-4 million PubMed records out of around 28 million.

But, to be clear not all records are equal.  Some will be to do with veterinary medicine (e.g. Serum amyloid A and plasma fibrinogen concentrations in horses following emergency exploratory celiotomy)  and others might be very specialised technical articles (e.g. Phase-matched virtual coil reconstruction for highly accelerated diffusion echo-planar imaging). So, we’ll be potentially including extra noise. We can mitigate against that – to a point.

In summary, searching all of PubMed is potentially very useful but there may be downsides. So with that in mind what do you think?

What’s happening?

Currently we are migrating to a new super-duper-shiney new server. This is a fairly large task – hence us being a bit quite recently. We’re hoping to have finished that in the next couple of weeks.

At the same time we’re working on the Trip community feature/service. This is experimental, so no timeline except for my usual impatience to get it delivered!

I’ve just uploaded the latest monthly – manual – batch of content. Most content to Trip gets added automatically but every month (as I have done each month for the last twenty years) I go to a number of sites and manually grab any new content.  At times this manual approach can feel like a bit of a chore, but generally I marvel at the breadth of new content being delivered.  This month I’ve found myself refreshing/boosting our links to Patient Decision Aids.

Finally, our annual accounts have been finalised and our subscription income has reached a key milestone – Trip feels more secure than ever. But I have no plans to allow this to make me feel comfortable. The moment we stop trying to improve is the moment we start to fail. Onwards and upwards.

RCTs in Trip – much improved thanks to RobotReviewer

RCTs are a crucial element of EBM and we’ve had a ‘filter’ for them for years. This allows a user to search and click the ‘Controlled trials’ filter and the results will only show clinical trials.  It’s one of our most used filters.

In the earliest iteration we used our own search filter to identify trials in PubMed and added them to Trip. This was ok, but lots of false negatives (missed trials) and false positives (identified papers as trials which weren’t).  A few years ago we started using the RCTs identified by the wonderful RobotReviewer team.  This used machine learning and made the results dramatically better.

Over the weekend we’ve used the latest version of the RobotReviewer code to make the identification of trials the most accurate yet!  Previously we had identified 479,197 trials but now it’s up to 532,479.  We had thousands of trials labelled as trials which no longer are and thousands we had previously missed. There were also a load of new trials that weren’t in Trip.

This is a brilliant piece of work and we’re indebted to RobotReviewer – thank you.

Summary: We have an easy to search collection of over half a million clinical trials!

Loads of extra full-text and a new results display to celebrate!

Full-text access is really desirable and it’s something we’re always trying to improve on. Up until now Pro users have been able to access full-text only if it exists on PubMed Central. This meant that 38% of all journal articles linked out to full-text.  We’re now working with an external partner who has some very clever technology and now – in some areas – the link out to full-text is over 80%.

We’ve redesigned the results to help people see these full-text options and so here they are:

Old results

New results

So, what are the changes:

  • If you’re a Pro user the link out defaults to the full-text. In the image above this is clearly marked with (full text) after the document title. There is also the option to link to the PubMed abstract.
  • If you’re a Pro user and we haven’t got a full-text link out we signify this with (PubMed) after the document title.
  • We’ve improved the spacing of the results.
  • The links to tweeting, starring etc have been made more obvious and aesthetically better.
  • If you’re a free user you can clearly see if a full-text is available.


The redesigned results is a great improvement while the massive increase in link outs to full-text is phenomenal.

Clinical Q&As – keeping them relevant

Trip started as a result of my work in running a responsive clinical question answering service for the National Health Service – many years ago.  I have had the pleasure of running a number of such services (alas, not one for a few years) and have kept these questions and answers within Trip.  Unfortunately, these have been neglected: they are often two years out of date and they look terrible:

Click here to see it on the web in all its glory!

This is a valuable resource, knowledge needs from real clinicians not the typical top-down approach to knowledge.  We’ve got well over 5,000 Q&As

As part of this years developments in Trip I’m keen to see if we can help save/update these Q&As.  So, how might we do this? Here are some thoughts:

  • Improve the design – obviously!  But as well as how it looks it might also be functional elements. Currently it’s the Q and then the A – with no structure.  Could we add things like ‘bottom line’?
  • Produce a priority list of Q&As to be updated.  This could be based on a number of elements e.g. (1) How popular is the Q&A (2) How old is it (3) We’re hoping to produce a system to find new, related, articles – so if we find some recent evidence that gets a higher weighting than those with none.
  • Open it up to the community – wiki-style – to edit and update. We’re going to be doing lots of work around the Trip community in the near future and this will lend itself nicely to a wiki-approach.

I’m really excited by this and if it works well we could, one day, allow users to pose questions and get the crowd to answer.


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