One of Dr Colenbrander's persistent interests has been in classification and coding. In the 1960’s he participated in the development of a new ophthalmic coding system in the Netherlands.
In the 1970’s, working with the WHO (World Health organization), the ICO (International Council of Ophthalmology) and the AAO (American Academy of Ophthalmology), he coordinated a complete revision of the eye codes in the 9th revision of the International Classification of Diseases (ICD-9, WHO, 1978) and its Clinical Modification for the US (ICD-9-CM, 1978).
Since 2008 he co-chairs the Topic Advisory Group (TAG) for Ophthalmology of the WHO and the ICO to prepare the vision chapter for ICD-11. ICD-11 will be a major revision of the ICD system to make it more compatible with modern data processing concepts. His specific interest is in extending the vision chapter beyond the classification of disease conditions, by emphasizing the classification of visual functioning.
Dimensions of Visual Performance. Introduction to the changes in ICD-9 (1976). PDF
Visual Functioning and ICD-11. Introduction to the changes in ICD-11 (2016). PDF
ICO proposal for Vision and Vision-related Functioning (2016) PDF
Characterization of Vision Loss in ICD-11 (2016) PDF
See also: Functional assessment - Guidelines and reports
