In the last blog, I looked at cast iron as a metaphor for strong. You could say that concrete was analogous as a metaphor for real: we want concrete evidence, not just something glimpsed in passing, or some vague speculation. I found over 300 papers in PubMed that presented concrete evidence: “…no concrete evidence demonstrating a role for endogenous APE1” ; “…concrete evidence of the essential contribution of non-starter lactic acid bacteria”; “…the most concrete evidence for cochlear power amplification to date.”

I may be doing the writers some disservice. Most commonly, the word concrete brings to mind the material. In introducing concrete as analogous to cast iron, I intentionally suggested that meaning. But the word concrete precedes the material concrete by a number of centuries. Coming from the Latin, its first use recorded by the OED (in 1471) is as an adjective meaning “united or connected by growth” and, not long after, “formed by union or cohesion of particles into a mass”. At much the same time, early logicians and grammarians applied it to things of the real world as opposed to abstract ideas. Perhaps medical writers attach this meaning to concrete, but I suspect they have in mind the “composition of stone chippings, sand, gravel, pebbles, etc., formed into a mass with cement”, which first appeared in 1834, and thus the writers are using concrete metaphorically.

I wouldn’t say it is an inappropriate metaphor, but it is an unnecessary word. What evidence would demonstrate a role for endogenous APE1 if it was not concrete—ie, not real—evidence? The “most concrete evidence for cochlear power amplification” is simply the best evidence.

Concrete is here what is called a “limpet adjective,” an adjective that is not needed and tends unthinkingly to be attached to certain nouns: sheer size, utmost urgency, true facts and prestigious prize. Prestigious means (COD) inspiring respect and admiration. Are there prizes that are not prestigious? Well, perhaps the Darwin awards and the Bad Sex awards.

If your evidence is strong then write “strong evidence” (but be aware that others may not be convinced). If your evidence is the first evidence then write “first evidence” (but make sure you’ve searched properly).

And the same goes for any other use of concrete in a medical article unless you are writing about the (see above) “composition of stone chippings with cement”. Searching PubMed for concrete retrieves nearly 10000 articles. Restricting the search to the titles of articles retrieves about 1000, most of which are about the material, although some are from semantics (e.g., concrete and abstract nouns). But that leaves about 9000 articles referring to concrete overviews, examples, suggestions or solutions. Concrete there means nothing more than real, and if it ain’t real, it ain’t worth writing about.

Neville Goodman is a retired consultant anaesthetist and a writer. He is co-author of a book on medical English.

Competing interests: I have read and understood BMJ policy on declaration of interests and declare that my only competing interest is my co-authorship of a book about medical English.