EDAC Turns Three

The exam item writers use this outline to identify all test requirements and the number of exam questions from each domain to be included on the examination. The five domains are: 

• Evidence-based Design for Healthcare
• Research
• Pre-design
• Design
• Construction & Occupancy 

EDAC eight-step process
The eight steps of the EDAC process are integrated throughout each of the content domains, and provide a framework for exam item writing that ensures a candidate has a comprehensive knowledge of the EBD process and how to integrate the process into the design and construction of healthcare projects.

The eight process steps are shown in Figure 1.

Developing a credentialing exam
With the assistance of the original psychometric firm, Applied Measurement Professionals, and the new psychometric firm, Castle Worldwide Inc., the EDAC exam task force worked with the psychometricians and test developers to learn the proper method for writing a statistically sound and legally defensible certification exam.

While all the “trade secrets” of developing a credentialing exam cannot be shared, the following section provides an overview of the terminology, question types, and general guidelines the item writers were trained to use when creating the examination. 

Subject matter experts/item writers
A subject matter expert is a person with expertise in a given field or profession who develops the content of examinations. These experts then train as exam item writers to write, edit, review, and validate questions. Each exam question is reviewed and validated by at least three other subject matter experts. 

Exam content outline
Before developing the exam, the subject matter experts determined the knowledge and skills that defined the minimum knowledge a candidate should have to become certified and defined the overall performance domains associated with a competent evidence-based design practice.

Each domain was then broken down into specific tasks, knowledge, and skills required. The exam content domains were peer-reviewed externally and then rated for relevance, criticality, frequency, and importance.

These results were then translated and weighted to create an exam that tests candidates on topics/content/processes in the proportion that they would observe and interact with the content on the job. The exam content outline guides the item development and examination process, ensuring that the examination reflects the relative importance of the required knowledge and skills.

The process is designed to evolve over time. 

Exam items
One of the first things the EDAC exam item writers learned was “exam questions” are called items. The EDAC exam includes 110 test items that cover the five content domains. Each item is comprised of the following components: 

The stem—The stem is the body of the question that defines the problem, describes the scenario, or provides qualifying information. On the exam, the stem will always be worded as a positively asked question and is void of words such as not or except. However, candidates will often be asked to select the best, first, or most appropriate option in response to the question or scenario being presented.

The key—The key is the correct answer. It is likely that multiple options to some degree could be considered correct. However, the key or correct answer is confirmed by the subject matter experts. This works in tandem with the stem language of selecting the best, first, and most appropriate option and requires the candidate to carefully read the stem and select the correct answer. On the exam, candidates will never be asked to identify all except, both A and C, all of the above, or none of the above.