I'll start; and KW, feel free to jump in.
In terms of the challenges, often in the surveys we'll be asked to identify our sex and it might just offer the options of male and female. As you've heard, across gender spectrum, that doesn't capture the diversity that exists in gender. Sometimes people will use terms such as “other”, but again, you're still missing a lot of that diversity. When there's actually an opportunity for people to self-identify their gender, that is very helpful. Sometimes people do ask the question, “What is your sex assigned at birth?”, which is often a less relevant question than gender identity.
The other thing nationally that exists, just thinking of my Porter flight here or whenever I'm asked to fill out a form, or with honorifics and that type of thing, is that I'm required to put in Mr., Miss, Ms. or Mrs., or Dr., which I can use sometimes as well.
Those things need to be considered, especially for health surveys, because that information about gender can then be stratified against health outcome information. That's really the critical piece: Can we stratify that information to see where there are disparities and gaps in our health?