Excerpt from the Canadian Ophthalmological Society evidence-based clinical practice guidelines for the management of diabetic retinopathy.

The objective of this document is to provide guidance to Canadian ophthalmologists regarding screening and diagnosis of diabetic retinopathy (DR), management of diabetes as it pertains specifically to DR, and surgical and nonsurgical approaches to the treatment of DR. These guidelines apply to all Canadians with type 1 or type 2 diabetes of all ethnic origins. Other health professionals involved in the care of people with diabetes may find this document helpful. These guidelines were systematically developed and based on a thorough consideration of the medical literature and clinical experience. These guidelines are not meant or intended to restrict innovation. Guidelines are not intended to provide a “cookbook” approach to medicine or to be a replacement for clinical judgment; rather, they are intended to inform patterns of practice. Adherence to these guidelines will not necessarily produce successful outcomes in every case. Furthermore, these guidelines should not be used as a legal resource, as their general nature cannot provide individualized guidance for all patients in all circumstances. Guidelines are not intended to define or serve as a legal standard of medical care. Standards of medical care are specific to all the facts or circumstances involved in an individual case and can be subject to change as scientific knowledge and technology advance, and as practice patterns evolve. There is no expectation that these guidelines be applied in a research setting. No comment is made on the financial impact of procedures recommended in these guidelines. Ideally, guidelines are flexible tools that are based on the best available scientific evidence and clinical information, reflect the consensus of professionals in the field, and allow physicians to use their individual judgment in managing their patients. These guidelines