hile dental laboratories and technicians are required to adhere to certain regulatory standards, voluntary certification programs are not regulated by any government body. However, there are organizations that exist to ensure that certification programs themselves set minimum standards. These standards address the structure/governance of the certifying agency, the details of the program, program transparency, information available to certificate holders and the public, and the recertification policies and procedures.
One such organization that publishes national certification standards is the National Commission for Certifying Agencies (NCCA). Complying with certification program and psychometric standards is extremely important to the Board. To assist with compliance of standards, NBC works with a third party testing company, JML Measurement & Testing Services, LLC. They assist NBC with several facets of creating, maintaining and operating NBC's extensive testing program and bring reliability and validity to the testing process.
In addition to psychometric and operational standards, the organization works to ensure governance and structure standards. For example, one of the standards refers to the composition of the board and outlines that, the governing board must include individuals from the certified population and a system must be in place through which all are represented, with voting rights, on the board.
NBC works to ensure that standards are met in a multitude of ways including, but not limited to:
- Job/Task Analysis
- Item Writing
- Item Review
- Pilot Testing
- Examination Form Development and Equating
- Examination Security
- Passing Score Studies
- Exam Maintenance
- Examination Materials Preparation
- Storage, Shipping and Psychometric Consulting and Review
- Documented Policies
The NBC Board of Trustees is composed in a manner to represent all of the certified population and shall determine the policies and manage the affairs of NBC. The Board is comprised of nine members, all of whom must be CDTs, with the exception of the dentist representative.
The Trust recently recommitted the organizations commitment to standards by voting to develop an internal audit program that could serve as a formal review of current and future certification processes. This will ensure that the certification program will continue to adhere to national standards.
Below are additional details regarding the ways that NBC works to ensure program and psychometric standards remain high.
Job Task Analysis
A job analysis is conducted every 5 years in order to identify the knowledge, skills, and abilities that a professional in a particular field should have. Within a test development effort, a well-conducted job analysis helps provide for the content-validity of the test that is later developed. The job analysis contributes to test validity by ensuring that the critical aspects of the job become the domain of content that the test measures. Job Analysis may also be referred to as task analyses, practice analyses, and role delineation studies.
- Job Task Outline for the Comprehensive Exam
- Job Task Outline for the Crown & Bridge Exam
- Job Task Outline for the Ceramics Exam
- Job Task Outline for the Complete Dentures Exam
- Job Task Outline for the Partial Dentures Exam
- Job Task Outline for the Orthodontics Exam
- Job Task Outline for the Implants Exam
A typical job analysis occurs in two phases. In the first phase a list of job-related tasks is generated and refined by a committee of experts, while in the second phase a national validation of that list of tasks is conducted.
Item Writing, Item Review, and Pilot Testing
NBC works to ensure that the examinations are both valid and reliable. We continue to work to maintain a strong item bank and thus continue to have annual item writing and review.
The item writing process takes place over several months through a call for subject matter experts (SMEs) who write questions that are pulled from industry available sources. From there, a group of SMEs meet for a comprehensive item review process, whereby each set of questions and answers are reviewed and cited back to specific sources.
Once the writing and review process is completed, each question undergoes pilot testing to ensure that it is statistically reliable before being activated into the item bank. Only questions that are approved through this analytical process are placed in the item banks.
As part of NBC's ongoing efforts to ensure that the questions included in its written examinations are contributing to the reliability of the examinations, NBC includes an additional ten field test questions embedded on each examination form. These ten questions are not graded, but instead are used to gather statistical data to allow NBC to determine if the field test questions may be used on future examinations. Using field test questions is a common practice in the certification and licensure testing industry.
Once active, each item continues to be monitored to ensure that it maintains relevance and positive reliability measurements. In the event that a question becomes outdated or unreliable, the question is pulled from active status.
Annual Technical Report
As part of NBC's commitment to upholding psychometric standards, NBC works with our testing partner to produce a report. This report looks at the previous years' for each certification examination in terms of numerous dimensions. These include mean, scores, passing rates, reliability estimates and performance of test questions. This is one of the most comprehensive reports for any certification organization in the United States. The reports below were produced by Professional Testing, Inc.
- Click Here for the 2018 Exam Statistics
- Click Here for the 2017 Written Exam Statistics
- Click Here for the 2017 Practical Exam Statistics
- Click Here for the 2016 Written Exam Statistics
- Click Here for the 2016 Practical Exam Statistics
- Click Here for the 2015 Written Exam Statistics
- Click Here for the 2015 Practical Exam Statistics
As part of the certification process, candidates are required to successfully complete a practical examination in the same specialty that they declared for the CDT Written Specialty Examination. This practical examination is proctored and graded by volunteer NBC Examiners.
The principal charge to Examiners is to be as equitable, consistent and objective as humanly possible in the administration and evaluation of the CDT practical examinations. NBC Examiners are eminently qualified with advanced years of experience and maintain multiple certifications. In addition, the NBC Examiners are thoroughly trained in all areas of certification and grade according to established CDT standards. The Examiners undergo thorough training which includes an apprenticeship program and continuous follow-up training.
With regard to procedures, one Examiner cannot determine if a candidate passes or fails. There are always three Examiners at each exam site and each Examiner grades independently. To ensure fairness, after independent scoring, the Examiners come to consensus on any areas where there may be significant disagreement. This process ensures that no one Examiner can individually impact the outcome of a candidate's scores without it being reviewed by the other Examiners for accuracy.
As the responsibility to the CDT program is critical, the selection process for examiners is extremely rigorous. NBC maintains a list of approximately 25 Examiners and announces vacancies from time to time based on need. Below are the qualifications to serve as an Examiner.
1) Professional Requirements: Examiners must be an active CDT, meeting continuing education requirements in full, hold certification in at least two specialties, and have a minimum ten (10) years' cross-specialty experience in dental technology;
2) Personal Background: Examiners are required to have interpersonal skills that are compatible with the established image for NBC examiners and must have no known affiliations with activities or organizations that are inconsistent with the goals and objectives of technician certification;
3) Availability: All Examiner candidates must agree to be available for a minimum of four tests each year, provided that six weeks' advance notice is given by the National office; and must be willing and able to obtain favorable fare travel arrangements for arrival in major destinations by 2:00 PM on the day prior assigned examinations.
4) Among the Active Examiners available for service, there must be reasonable representation of the total candidate population being tested by the NBC; specifically, Examiners must, as a group, be experienced as employed technicians, laboratory owners, educators and military technicians; they must reflect formal education, on-the-job and military training; and they must have geographical diversity.