CDI Certification FAQs
General
What does a “disease intervention professional” do?
Disease intervention professionals are public health professionals who reduce the community spread of infectious diseases through contact tracing, partner services, health education and facilitating access to health care. They do this through activities such as person-centered interviews, collection of enhanced surveillance and community assessment data, contact tracing, field specimen collection, field investigation, emergency preparedness, community outreach, and collaboration.
Why is there a new certification for disease intervention professionals?
The CDI certification recognizes and affirms the expertise of disease intervention professionals. It sets a consistent national benchmark for knowledge and skills while also providing recognition for those working on the front lines of infectious disease prevention and control.
When will the CDI exam launch?
The first testing window for the CDI exam is tentatively scheduled for Spring 2026. Applications will open in early 2026.
What is the format of the CDI exam?
The computer-based 3-hour CDI exam will be 120 multiple choice questions. There will not be essay questions or observational elements (such as mock interviews) on the exam.
What topics are covered on the CDI exam?
The CDI exam assesses proficiency in 6 domains: Planning & Case analysis, Interviewing & Case Management, Field Services & Outreach, Surveillance & Data Collection, Collaboration, and Outbreak Response & Emergency Preparedness.
What types of skills does the CDI exam assess?
The CDI exam will assess a broad range of skills that support the 6 domains of the exam such as communication, interviewing techniques, prioritizing case load, field safety, collection of surveillance data, maintaining confidentiality, and locating and notifying contacts. The full range of skills that will be assessed is listed in the CDI Exam Content Outline. The tasks listed within each domain represent the skills that will be assessed on the exam.
Are the questions on the CDI exam specific to certain infectious diseases?
The exam does not assess clinical knowledge of specific diseases. Instead, the exam focuses on the skills required to conduct disease intervention activities regardless of the specific disease area.
Can I re-take the exam if I don’t pass on my first attempt?
Yes! Candidates who do not pass the exam on the first attempt can re-take it once in a 12-month period.
Will the exam be offered in any other languages?
The CDI exam will be offered in English and Spanish.
CDI Eligibility
What are the requirements to sit for the CDI exam?
Why does the CDI require at least one year of disease intervention experience?
The CDI assesses proficiency in key disease intervention skills. People who have been a disease intervention professional for less than one year may not have sufficient training and experience to acquire all of the skills necessary to successfully pass the CDI exam.
What types of work experience count towards the required number of years of “applicable community experiences in counseling or health outreach” for eligibility?
Jobs that require interaction with a variety of populations in a community, clinical, or governmental setting should count towards this requirement. Jobs such as outreach, community engagement, direct service delivery, and needs assessment and referral are some examples. For a complete list of criteria and examples, you can read the Community Experience tab on the CDI Eligibility Requirements webpage.
Can additional years of disease intervention experience count as “applicable community experiences in counseling or health outreach?”
Yes, additional disease intervention work experience can count towards the required experience.
How is work experience calculated?
Work experience should be equivalent to the required number of years of applicable experience and may be calculated based on less than full-time employment. For example, a part-time position of 20 hours per week for 4 years is equivalent to a full-time position of 40 hours per week for 2 years. Experience can be acquired through formal paid employment or through voluntary activities such as AmeriCorps, unpaid internships, Peace Corp, or other volunteer work provided it meets the criteria listed on the CDI Eligibility Requirements webpage.
CDI Exam Preparation
What study resources will be available to help me prepare for the CDI exam?
There will be a variety of study resources available on the UniversiDI website to help eligible DI professionals prepare to sit for the CDI exam including the content outline, study guide, flash cards, sample exam questions, and practice exams. NBPHE will also host review sessions taught by subject matter experts in each domain. Candidates are encouraged to use the resources that best match their individual learning style. Study materials are expected to be released in late fall 2025.
Do I have to pay to access the CDI study resources?
No, the study resources for the CDI exam are available at no cost on the UniversiDI website.
What is the best way to study for the CDI exam?
The most effective approach is to create a study plan that balances reviewing core content with practicing application-based questions. Start by reviewing the CDI Exam Content Outline to understand the topics that will be covered, then take a practice test on the UniversiDI website to get a feel for the question style and identify strengths and areas for improvement. From there, use the study guide, review recommended references, attend a live or on-demand review session, and incorporate any training materials from your workplace. As you study, set aside consistent time each week and consider joining a study group for accountability and discussion. Once you feel prepared, take another practice test to measure your progress and build confidence.
How much time will it take me to prepare for the CDI exam?
Preparation time varies depending on your background and experience. On average, candidates spend between 1 and 6 months studying, devoting a few hours each week. If you’re newer to the field, you may want to give yourself more time to review key concepts. If you have several years of experience, you may need less time, but you should still plan for focused review sessions to refresh your knowledge and skills with the exam format.
I am nervous about taking a standardized exam. What should I do?
Feeling nervous is completely normal. A structured and consistent study plan can help reduce anxiety by building familiarity with the content and exam format. The UniversiDI website includes tools to help you create and follow that plan, such as the digital CDI Planner, practice tests, flash cards, and the CDI study guide. These resources are designed and reviewed by subject matter experts to align directly with the CDI exam.
Practice questions are especially helpful for reducing uncertainty about what to expect. Be sure to take regular breaks during study sessions to avoid burnout, and use stress-management techniques such as deep breathing, stretching, or short walks. On exam day, aim for a good night’s sleep, eat a balanced meal, and arrive early to your exam session so you feel calm and prepared.
I have been a disease intervention professional for several years. Do I still need to study for the CDI exam?
Yes. While professional experience provides a strong foundation, the exam is designed to assess knowledge and skills across the full scope of disease intervention practice. Studying ensures you refresh less familiar topics, understand how material is presented in a testing environment, and build confidence with the exam format. Even seasoned professionals benefit from a structured review to perform at their best on test day.
CDI Recertification
Why does the CDI require recertification?
Unlike degrees and certificate programs, certifications must be maintained over time. Maintenance of the CDI credential ensures that certificants are staying current on emerging trends and best practices in the field of disease intervention and continuing to meet a national standard. Recertification also contributes to ongoing professional development through lifelong learning.
How often will I have to recertify my CDI credential?
How many credits will I need to recertify?
CDI certificants must earn a total of 30 recertification credits during the 3-year recertification period.
Is there a fee for recertification?
There is a fee of $95 due when you submit your recertification application.
What types of activities count for recertification?
Public health and disease intervention related activities that relate to the CDI Content Outline such as work experience, conferences, publications, presentations, courses, webinars, workshops, and volunteer activities can count towards recertification. The CDI Recertification Activities Credit Guide has a full list of activities that count towards recertification.
Do I have to use certain continuing education providers or take certain courses to recertify?
Unlike other professional licenses or credentials, CDI certificants do not have to attend certain paid trainings or events to recertify. The recertification credits you earn can be from any organization/provider. NBPHE does not have a list of authorized providers for recertification activities. NBPHE accepts any public health or disease intervention related activity for recertification as long as it fits in the categories listed in the CDI Recertification Activities Credit Guide. In fact, many CDIs earn credits by participating in webinars, conferences, meetings, and events through their job.
How are recertification credits calculated?
Each hour (60 minutes) spent participating in a recertification activity equals one recertification credit.
What if the amount of time spent participating in a recertification activity does not equal a whole number?
If the amount time you spend participating in a recertification activity does not equal a whole number, you can round up to the nearest whole number. For example, a disease intervention related webinar that lasts 1.5 hours can count for 2 credits.
Can my work role in disease intervention count towards recertification?
Yes, CDI Certificants can earn 10 recertification credits per 3-year cycle for work experience.
Can I count volunteer activities towards recertification?
Yes! Your volunteer service such as participating in a community outreach event, joining a public health awareness event, or being a member of a board or committee (e.g., item writer/ reviewer, study guide, passing score study, exam review, job task analysis) will count towards CDI recertification.
What should I do if I participate in an activity that I think may count towards recertification, but it is not listed in the CDI Recertification Activities Credit Guide?
If you are not sure whether an activity will count towards recertification, you can email a brief description of the activity to NBPHE staff at [email protected] to request guidance.
The Certified in Disease Intervention (CDI) Certification Program is supported by Cooperative Agreement CK20-2003 from the Centers for Disease Control and Prevention awarded to the Association of Schools and Programs of Public Health (ASPPH) and sub-awarded to the National Board of Public Health Examiners (NBPHE). The contents are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Prevention.
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