OnlineBookClub.org

vs or vs.

An editor deducted a point because I wrote 'vs' and not 'vs.'

'vs.' is correct, but 'vs' is also not wrong. While the former is more prevalent in the US, the latter is more common in the UK.

Do reviewers need to adhere to a specific English variant?

You do not need to adhere to a specific variant, but you must be consistent and not switch between the two in your review. If you are marked down for using British English, you should ask for a recheck. Make sure that you include a reputable link showing that both forms are correct. Your points should be restored.