The Top 10 Undefined Acronyms / Abbreviations

NASA has achieved something that few organizations have. We're not talking about the fact they put a man on the moon. What interests us is that NASA has become an abbreviation that doesn't require definition. Many style guides specifically state that abbreviations in common use do not require a definition. And since NASA is so well known (they did put a man on the moon after all), the word 'NASA' can typically be included in a document without ever using its definition (National Aeronautics and Space Administration).

There is a difference between acronyms, abbreviations and initialisms. For the purpose of simplicity, we use 'abbreviations' to refer to acronyms and initialisms.

Most abbreviations do require a definition. In any case where readers might be confused by TLAs (three letter abbreviations), it's important that they be defined in the text or in a Table of Abbreviations. A research proposal or article with complicated and confusing abbreviations is one that will quickly face rejection. The problem is that authors become so familiar with abbreviations that they forget to define them.

To test how prevalent the problem is, we used PerfectIt, Intelligent Editing's add-in for MS Word that locates undefined abbreviations, to check 3000 randomly selected documents. PerfectIt provides a powerful way to check for undefined abbreviations because it:

  • scans an entire document to locate abbreviations that have not been defined
  • recognizes common abbreviations (such as 'NASA') that do not require a definition
  • checks for a table of abbreviations and doesn't alert users if the definition is found there.

The Top 10

Each document we tested was 1500 words or more and was downloaded from the internet using the search term "final report" to ensure that the selection was random. The results astounded us. We found that 90% of reports contain abbreviations that are not defined. As explained above, PerfectIt recognizes common abbreviations (e.g. UK, USA, and around 150 others). The principle is that if authors probably intended not to define the abbreviation, then PerfectIt won't alert them. However, in 90% of documents, abbreviations that are likely to require definitions were left undefined. The most frequently used abbreviation without its definition was 'NGO', but there were over 7900 other undefined abbreviations that we came across. Here's the full Top 10.

Table 1: The 10 most often undefined abbreviations
RANKPHRASEFREQUENCY (% OF DOCUMENTS)
1 NGO 5.4%
2 ICT 2.7%
3 IP 2.5%
4 PI 2.1%
5 SME 2.0%
6 PCT 1.9%
7 HR 1.8%
8 GDP 1.8%
9 HE 1.8%
10 UNDP 1.7%

We verified these findings with a series of manual checks on the results. We found PerfectIt misses less than 2% of definitions and falsely identifies acronyms in just 3% of all instances.

The Audience Matters

An interesting thing to note about the Top 10 is that these are common abbreviations and that readers may know what they mean. A report on foreign aid may be able to use the abbreviation 'NGO' in the knowledge that readers know that it stands for 'non-governmental organization'. But authors should be careful before making assumptions like these. For instance, what does 'PI' stand for?  Is it 'performance indictor', 'private investigator' or 'personal injury'? The abbreviation 'PCT' may be well understood in Britain to mean 'primary care trust'; but what if somebody outside of Britain reads the article / report?

For proofreading purposes, the Top 10 represents an ambiguous list. These are not the most common abbreviations that can always be used without a definition. And they are not the least common abbreviations that must be defined. They're abbreviations where authors should consider their audience and decide based on that. However, we'd suggest that where there is any doubt, authors should make sure they define the abbreviation in the first instance. Put simply, it makes the document easier to read and there are not usually any good reasons to exclude the definition.

It's also important to think about including a Table of Abbreviations. Less than two percent of the documents we scanned included a Table of Abbreviations. That's probably because most people think of generating a Table of Abbreviations as a time-consuming task. But with PerfectIt, a Table of Abbreviations can be automatically generated in a single click. It takes just seconds, and it means that readers can quickly find out the meaning of any terms that confuse them.

What to Look For

The percentage of documents that leave at least one abbreviation undefined is beyond anything we could have imagined. Six documents we tested had over 50 different abbreviations left undefined, and one document actually had over 100. Imagine working your way through a report with 100 undefined abbreviations. Of all the documents we have tested, that must be the most incomprehensible one we have ever come across.

The extraordinary proportion of documents produced with undefined abbreviations suggests that authors are unaware of how easy it is to correct this with PerfectIt. The program is free to try, and in seconds it can find every abbreviation and determine which ones have been defined and which ones have not. It guides users to the first use of each abbreviation, and it can generate an entire table of abbreviations. That same job can take a human being several hours.

However, if you are proofreading manually, we suggest you consider each abbreviation carefully. Remember that the audience may not be familiar with specialized terminology; where in doubt, include the definition.