Trip Database Blog

Liberating the literature


October 2019

When old news makes the headlines

I do some work for BMJ Evidence-Based Medicine and one aspect of this is looking for practice changing research. Part of this is exploring the Altmetrics for each article I find.

One article, with an exceptionally high Altmetric score (1629 as I type this) is Bedtime hypertension treatment improves cardiovascular risk reduction: the Hygia Chronotherapy Trial. The aim of the trial was “to test whether bedtime in comparison to usual upon awakening hypertension therapy exerts better cardiovascular disease (CVD) risk reduction.”  The trial concluded:

Routine ingestion by hypertensive patients of ≥1 prescribed BP-lowering medications at bedtime, as opposed to upon waking, results in improved ABP control (significantly enhanced decrease in asleep BP and increased sleep-time relative BP decline, i.e. BP dipping) and, most importantly, markedly diminished occurrence of major CVD events.

This reminded me of a question we’d been asked in the past. A bit of rummaging around and I found “am or pm what is the optimal time to take once a day antihypertensives?” which we answered in 2010.  In short the evidence found – back then – that bedtime was typically the better time to take this anti-hypertensives: giving better blood pressure control and reduction in events.

Why am I highlighting this?  One angle could be to question the necessity of the trial. I’m acutely aware of the work by the likes of Iain Chalmers and Paul Glasziou on research waste (eg Research waste is still a scandal). However, this is not something I’m in a position to comment on, I feel I don’t have the expertise.

But my fascination is why is got such a high Altmetric score. I see Altmetrics as a sign of interest and/or newsworthiness. But to me this is not new knowledge. It might now have more ‘power’ but I had thought that bedtime consumption of anti-hypertensives was, typically, the best thing to do.

So, to me, this demonstrates the difficulty of spreading knowledge. The knowledge has been known for years. The Altmetric score demonstrates there was a real hunger for the knowledge. Yet, somehow, until this new paper came out the knowledge was either inaccessible or clinicians didn’t articulate the question and search for the evidence! Slightly depressing either way….

Interesting search problem!

We’ve had a really interesting problem, one I’m at a loss to answer…

The user was looking for articles on ‘lead’ (the metal) and was clearly getting lots of noise from articles that use the not metal version of the term, such as:

  • Lead-I ECG devices for detecting sym….
  • …Bone Loss and Leads to Faster…

So, how might we get around this?

I tried this lead* NOT leading and it got better results (18,295 from 372,066) but I can’t construct a working search that adds additional terms (eg lead* NOT (leading OR leadership)).

Any solutions?

Unblocking Trip’s indexing ‘fatberg’

To get content in to Trip it needs to be indexed – another term for processing.  This starts when we add basic records to the site, this can be as simple as document title, URL and year of publication.  Our systems then process the records before they arrive in the searchable index of records.

The basic records get in to our system in two main ways:

  • A monthly manual upload of new content.
  • Automatic grabbing from sites such as PubMed.

Recently we noticed that records from PubMed were not getting in to Trip in a timely manner, caused by an indexing ‘fatberg‘. To cut a long story short we have unblocked our indexing pipes and we’re now all back, ship shape and Bristol fashion!

Questions in need of answers… social media addiction and risk of sedative medication

Our community Q&A has two questions needing an answer:

  • What is the best scale for social media addiction?
  • Is there any cross sectional study about the risk of uses sedative medication?

If you know of any relevant literature then please let us know.

As a reminder the Trip Community Q&A tries to link unanswered clinical questions with users likely to know the answer – the hope being that they are best placed to answer it. The idea has been inspired by sites such as Quora.

Anatomy of a clinical question

When starting the community Q&A I was worried that people would be lazy, not search themselves and simply ask the question. This has not been the case. The overwhelming majority have been complex and legitimately not fully answerable via Trip!  Here are a few examples with my interpretation underneath:

In children with pharyngitis, how useful are prediction tools to select whom to perform microbiological tests?

This was difficult to answer for a couple of reasons:

  • For the person asking the question: He was Spanish and therefore I wonder about the knowledge of synonyms. He asked about ‘prediction tools’ whereas the (English) literature tends to use the phrase ‘decision rules’. So, when searching that starts from a point of great disadvantage!
  • From Trip’s perspective we simply did not index the main document, from CADTH.  We tend to grab all the content from them so I’ll need to understand why it’s not in our index!

The adult patient developed insomnia due to metoprolol, is there B-blocker less associated with causing insomnia?

The main issue is the lack of clarity of evidence – as mentioned in the answer it is often contradictory. So, was the motivation of the questioner to try to get a more definitive answer than suggested by the literature?

What is the possible effect for giving an ACE +NSID+diuretics in elderly patients?

We’ve actually been asked this question twice!  This is a problematic search due to the issue of synonyms. But, for me, the issue of the disparate nature of the literature is the key problem. There are a number of references, none are definitive. So, that induces an uncertainty all of its own.  Clearly a review is needed, and this is what the community Q&A provided, but without it, it’s tough for a health professional to start to make sense of the literature.

I feel there should be more fundamental lessons but I clearly need more thinking time!

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