National Center for Health Statistics

Development of an X Gender Marker Definition for the US Passport: 

Methodology and Implications for Asking about Gender

Kristen Miller, Ph.D.

Collaborating Center for Question Design and Evaluation Research

Disclaimer: This is not an official publication of the National Center for Health Statistics (NCHS) or the Centers 

for Disease Control and Prevention (CDC) as this research has not undergone NCHS or CDC clearance. The 

contents and any conclusions in this document are those of the author(s) and do not necessarily represent the 

official position of NCHS or CDC.
CCQDER/NCHS Projects

Applied Projects: Develop/Test Single item, non-binary gender question

• US State Dept: Passport (n=100)

• US State Dept: Employee Management System (n=44)

• NCHS: Health Survey (n=50)

Research Studies: Examine performance of 2-question design

• Cognitive interviewing studies 

• Split-sample experiments with embedded error/construct probes

Studies available: www.cdc.gov/qbank
Opposing Interests for Gender Minority Respondents: 

Inclusion and Privacy

Inclusion (benefits)

• Recognition and affirmation

• Data collection to understand and reduce disparities

Privacy (risks)

• Exposure to rudeness and degradation

• Exposure to discrimination, e.g., job loss, housing, access to health care

• Personal safety; Physical harm

• Inclusion/Privacy relationship informed by context: 

• Perceptions of purpose

• Perceptions of privacy

• Question design
Passport Applications

• Addition of X marker to M (male) and F (female)

• Purpose of X option: 

• Recognition and affirmation

• Not for research purposes/Data quality not consideration

• Context: 

• Application process, self-report, paper and pencil

• A public, travel document

• A legal, government document

• Research Question: How should X be defined given purpose and context? 
Excerpt of Mock-Up Passport for Testing 
Excerpt of Instructions Page 3
Passport Application

Inclusion:

“I prefer to have X because I'm not in the other boxes.” 

“The fact that the passport serves as legal documentation made the option of selecting X even more poignant.” 

“I would say that [including an X] means that the US is finally recognizing that my gender identity is valid... to have an official identifier for my 

gender identity.” 

Privacy: 

“Yeah, especially thinking about international travel... I'm thinking about the best way to mitigate any sort of issues that could come up.... I think I 

would [select X] at a doctor's office. Just because I think as medical professionals, instead of assuming, it's kind of your job to, like, ask questions 

and build rapport with your patients.... I think I would choose it on a driver's license. Because nobody's really looking at your gender on the driver's 

license. But on a passport, I feel like it's a little bit different. Because everything on a passport is under heavy scrutiny.”

“I guess it confirmed to me that having an X on my United States passport is only validating to me, and only a hazard if I were to leave the country. 

So, if TSA is going to question me.... if I go to another country, and I’m victimized or harassed or questioned or judged, I’m thinking ‘what’s the 

benefit?’”

Final Wording: X = unspecified or another gender identity

• ‘Another gender identity’ creates inclusion

• ‘Unspecified’ provides an opt-out, such that X doesn’t necessarily mean gender minority
Government Employee Information

• Creating a non-binary gender data element

• Purpose: 

• Recognition and affirmation

• Identify gender minority employees to track equity goals; increased importance of data quality

• Context: 

• Web-based, Employee Management System

• Government agency, politically dependent

• Research Question: What should the question be given purpose and context? 
Department of State

GEMS – Global Employment Management System

Privacy Act Statement

Ethnicity and race information is requested under the authority of 42 U.S.C. Section 2000e-16 and in compliance with the 

Office of Management and Budget’s 1997 Revisions to the Standards for the

Classification of Federal Data on Race and Ethnicity. Providing this information is voluntary and has no impact on your 

employment status, but in the instance of missing information, your employing agency will attempt to identify your race and 

ethnicity by visual observation.

This information is used as necessary to plan for equal employment opportunity throughout the Federal

government. It is also used by the U.S. Office of Personnel Management or employing agency maintaining the records to 

locate individuals for personnel research or survey response and in the production of summary

descriptive statistics and analytical studies in support of the function for which the records are collected and maintained, or for 

related workforce studies.
Government Employee Information

Privacy Concerns: 

“The hard thing is – and I feel this less now but more so when I was first coming out – I felt 

uncomfortable putting trans-ness or trans or transgender on any kind of legal form because there is 

something in the back of my head that says, ‘they’re going to come for you for this.’ Because it’s 

happened before. Because there have been past administrations that have been openly hostile and when 

we put ourselves on a form in any way, we are opening ourselves up, ultimately, to having someone say, 

‘Alright, you’re fired for this.’” 

"Number 4 [sexual identity] would have been something I would have continued to lie about [she marks 

‘straight’]. And same if I was gender non-conforming. I would put what was on my birth certificate to 

protect myself." 
Final Wording

Are you:

Mark all that apply.

 Male

 Female 

 Transgender, non-binary, or another gender

• Privacy statement eliminated (otherwise ‘unspecified’ would be used)

• Identity labels increase sense of inclusion:

“I don't consider myself a regular female. And I certainly don't consider myself male. And I want to distinguish between what a female is 

and what a trans female is. We are not the same and I try to respect that boundary. So, whenever I have the ability to identify as 

transgender, that creates a comfortable middle ground for me."

• ‘Mark all that apply’ increases inclusion:

“I feel like it’s important for people to see that I’m a man and recognize that. And it’s also important because I’m trans and will have 

automatically different experiences [from cisgender men and] that also be recognized. So, when I see that on a form, I want to put both 

options, you know? Because they’re both relevant, but sometimes forms don’t let that happen.”
General Population Health Survey

• Creating a non-binary gender data element

• Purpose: 

• Identify gender minority respondents to understand health disparities; high quality 

data essential

• Context: 

• Interviewer administered

• Privacy protections

• Research Question: What should the question be given purpose and 

context? 
General Population Health Survey

Are you:

Mark all that apply.

 Male

 Female 

 Transgender, non-binary, or another gender

Privacy: Verbally assured with consent; no identified privacy concerns

Inclusion: Similar to GEMS study
Privacy/Inclusion: 

What sex were you assigned at birth?

“That was me when I was a little baby and now, I'm an adult.... Kind of like trying to figure out what genitalia 

you have. Which doesn't really seem work-appropriate to me." 

“But do you need to understand what their genitals are to work with them? [The transgender community is] one 

of the few communities where it's acceptable to ask about our genitals.”

“It is triggering language.... It's a little bit like dead-naming a transgender person.... Even though I openly 

admit I'm transgender, I would not answer that question.”

"Ugh. I hate it.... The journey of a transgender person is extraordinarily difficult. There is a period of great 

difficulty in understanding their gender. And it runs in contrast and contrary to the assigned gender at birth. 

You're doing everything in your power to get away from this. And undergoing some rather painful procedures in 

order to get away from who you were.
Context/Purpose: 

What sex were you assigned at birth?

"I would definitely be more comfortable saying it to a doctor because I would 

assume the doctor is examining me and trying to keep me healthy.... So, they would 

have a good reason of asking that question.... How can we best treat this person's 

health? So, I wouldn't have an issue answering that question in that context.“

“That, to me, is a hard do-not-do-that! I think that's especially problematic for an 

employer to phrase a question like that... because it's not how I define myself. In 

fact, [it’s] the opposite of how I define myself.... So that's a problem. And also, this 

is my legal identity -- my passport, my driver’s license -- all do not have that sex on 

them. So how is it relevant to my employer what my history was?"
Next Steps

• Spanish Translation/Cognitive Interviewing

• Cog Study to understand non-minority response processes

• Large (n=10,000) survey experiment

• Consider need for biological/physiological measures 

2023 National Health Interview Survey

For this next question you may select more than one answer. Do you currently describe yourself 

as male, female, transgender, nonbinary or another gender? 

1. Male 

2. Female 

3. Transgender 

4. Nonbinary 

5. Another gender (Follow-up: “What term do you use to describe your gender?”)