Developing the 2018 Canadian consensus guidelines on the primary care of adults with intellectual and developmental disabilities involved a group of 45 family physicians, psychiatrists, nurses and other health professionals from urban and rural areas across Canada. The guideline developers had extensive experience in primary care of people with IDD. Many were involved in developing the previous guidelines. All participants came together for a colloquium (meeting) in 2016, in Toronto.

Small groups reviewed knowledge on specific topics assigned to them according to their respective areas of expertise. They also proposed wording for revising or adding to the previous guidelines. A Colloquium Synthesis Group and an Editorial Group were established. The latter was a sub-group of the former. The Colloquium Synthesis Group consisted of five family physicians, a psychiatrist, two nurses, an ethicist, a librarian and a research associate. Two additional external consultants with expertise in methods of guideline development provided advice.
The Colloquium Synthesis Group and Editorial Group worked in tandem to formulate the text of the guidelines based on discussions with colloquium participants. The Colloquium Synthesis Group guided decisions regarding the methods used for categorizing the types of knowledge and for distinguishing the strength of recommendations. The first two authors of these guidelines (a family physician and a research associate) independently categorized the type of knowledge of publications that the working groups reviewed and proposed the grading of strength of recommendations (see How to use and understand the guidelines).

The leaders designated for each section of the guidelines (four family physicians and a psychiatrist) also separately ranked what they considered to be the most important recommendations to promote in any clinical practice and those recommendations that pertain to health issues that are most commonly overlooked in patients with intellectual and developmental disabilities. Discrepancies were noted and resolved by discussion among those involved. The final results were communicated to all the participants in the guidelines update colloquium for their approval.