Applying the developmental perspective in the psychiatric assessment and diagnosis of persons with intellectual disability: part II – diagnosis

Background The descriptive phenomenological categorical psychiatric diagnostic systems that are currently being used in the field of intellectual disability do not adequately provide for the special needs of persons with intellectual disability. Many relevant diagnostic questions are left unanswered or are only partially accounted for. This is particularly true for persons with low developmental levels. Method A solution to these stumbling blocks is sought in enhancing the contemporary categorical diagnostic systems by also applying methods derived from the developmental perspective. Result By taking the levels of emotional and personality development, in addition to other developmental aspects into account, the clinical picture becomes more comprehensible and explainable. Conclusion The integrative diagnosis that results from this combined approach provides an insight into the processes that have led to the disorder and enriches one's understanding of the presentation form of the disorder. This diagnosis is process‐ rather than symptom‐oriented and is particularly useful with persons who have a low level of psychosocial development.