Conventions for long date format

When to use

The NHS CUI advises that the long date format is always used when information is produced for patient consumption. Such as, handouts, appointment reminders, and forms.  

This is in contrast to the short date format that is always for healthcare worker material.

Format

To simplify things, I'd suggest a long date format of:

09 September 2008

or whenever the day of week can be included:

Tuesday 09 September 2008

Differences from short date format:

The long date format does not use a hyphen, but instead a single space between elements.

The month is always written in full.

The day of week is always written in full.

Differences between my simplified specification and the NHS CUI:

Day of the week

I advocate for writing the full day of the week, as opposed to using the abbreviation as suggested by the CUI.

Many consumer facing products write the full day of the week, not the abbreviation. See Date Display - real-world examples for further details.

No ordinal numbers

The NHS also permits an option of the long date format that uses ordinal numbers. For instance,

9th September 2008

In ordinal numbering, the 0 is not included in digits under ten. In addition, a superscript is always included with the st, nd, rd, or th.  

To me, ordinal days adds complexity and doesn't improve readability. People naturally add this pronunciation in any way.

There are also problems with ordinal number notation, in cases where these letters are not in superscript, they may be misinterpreted as medical abbreviation - such as ST could mean sinus tachycardia, soft tissue, or standing.

This article from EnglishClub shows the varying levels of formality that the date can be written in. The date as suggested above 09 September 2008 is the middle of the road, and seems like a reasonable compromise.

The long date format has the potential to vary a lot

I realize that the long date format will vary between countries and languages.

Therefore, it likely makes sense that organizations will need to be able to specify how they would like their long date format to be displayed. For instance,

• Ability to set the order between British and American English
• Ability to set where, if any, the commas in the date appear

The long date format, in general, is designed to be more reader-friendly and mirror that of common diction of the region. There likely are many acceptable version of this.

This is in contrast to the short date format, where the specifications outlined in the other document are designed to increase clarity and reduce confusion of a date format that is prone to misunderstanding.

Further References

How to write dates correctly in English, GrammarlyBlog
https://www.grammarly.com/blog/how-to-write-dates/

Date format in UK vs US
https://english.stackexchange.com/questions/68844/date-format-in-uk-vs-us

Linguapress: Expressing dates in English
Demonstrates some of the variations in formal writing of the date.
https://linguapress.com/grammar/dates.htm

From the series Building the EHR

Section: Conventions / Date Display

• Date Display - Short Date (EHR convention)
• Date Display - Long Date (EHR Convention) (this article)
• Date Display - existing standards
• Date Display - variations by country & language  
• Date Display - real-world examples

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