I’d steer clear of using WNL because it is so vague and ambiguous. If you were to ever go to court it would be hard for a defense attorney to evaluate and it would provide ammunition for the plaintiff’s attorney to question and criticize. Vague chart notes imply inattention or haste and can influence the outcome of “failure to diagnose” malpractice suits. With this said, that doesn’t mean you can’t use abbreviations at all, it just means that this one isn’t the most wise to use.