basic etiquette - what name format in an academic reference?

[parietal]

First time I'm writing a big important reference for a junior colleague to get a big prize. So here is an example of the first paragraph -

I'm delighted to nominate Dr Anna Smith for Big Prize. I have known Anna since 2010 ...

but do I write "I have known Anna " and continue with Anna as the name for the rest of the letter

or do I write "I have known Dr Smith " and continue with Dr Smith as the name for the rest of the letter?

Dr Smith feels odd and formal, but maybe it has less gender bias and shows off how senior she is. Even though I first knew her before she had a PhD.

What should I go for?

Pfffttt... never thought about it, but good questions.
I have always used 1st name.
We aren't that formal, everyone is a Dr so why repeat that?
1st name is how I think of the colleague.
However, come to think of it, for a European reference, maybe Dr. X is better. Or anywhere that 'more formal' tone is expected.

I tend to use the formal Dr Smith form. But if you’ve known your colleague since she was an undergraduate then say do, and comment on her enduring talents and abilities.

Dr Smith. That is her professional title, and you’re writing about her professional accomplishments, in a professional context.

Is it possible to find previous years' nominations and take your cue from that?

I'd use Dr Smith. It's a reinforcement of her professionalism over her friendliness. If also sets the bar for people who don't know her so well to respect her professionalism before thinking she's a good pal, a nice lady or other gendered stereotypes.

Thank you.

Added question- I addressing the letter to a German organisation so should it be

Prof Dr Smith

Or just Prof Smith as it would be in UK/USA?

If it’s for a German institution definitely Dr Smith!

Is her rank actually Professor?

If so, formally it would be Frau Professor Doktor Smith. Or Frau Doktor Smith.

But as an English-speaker, or from a UK/USA context, you don’t need the sex marker “Frau.”

Is she a professor??

I would just stick with the title in the U.K., don’t get tied in knots trying to give her a German title. They know perfectly well what the U.K. convention is.