Why a series of assessments?
The development of the PAS-ADD assessment tools has responded to three fundamental challenges facing the assessment of mental health problems in people with intellectual disabilities (ID).
Communicating with the person
The most obvious problem faced by a mental health assessor is that of communicating with, and understanding a person’s problems. Even the question ‘do you feel anxious?’ poses a challenge to someone with developmental disabilities, and even those with borderline ID and apparently good language skills. Anxiety is an abstract concept covering a multitude of experiences. Someone without ID knows this and can also look back over a period of time to aggregate their own personal experiences and give a meaningful answer. This is a formidable challenge to someone with ID. When it comes to the most abstract concepts, such as delusional beliefs, the problem becomes even greater.
Relying on what other people say
This is perhaps the single greatest difference between assessing the general population and assessing people with ID. The less language the person has, the more we have to rely on the knowledge of others. Usually, the people with the greatest knowledge of the individual (eg. parents and frontline staff) have limited or no knowledge of psychopathology. Often the people that these primary informants most often communicate with are not psychiatrists or psychologists, but other staff such as nurses, social workers and speech and language therapists etc. One of the main aims of the PAS-ADD tools is to maximise the contribution of these other staff to the overall assessment process.
Even in the general population the recognition of mental illness is not perfect; depression and anxiety are particularly likely to be overlooked. However, the recognition of mental health problems in populations of people with ID is much more problematic. The people themselves are unlikely to recognise they have a problem, and most family doctors are not trained in communicating with people who have ID. Also, the presence of ID may lead to the presence of ‘strange’ behaviours, making it probable that a genuine mental disorder is seen as just a part of the disability. Family members rarely have the knowledge necessary to disentangle complex behaviours, and so the problem often remains buried.
PAS-ADD in relation to these three challenges
The PAS-ADD tools were designed as a response to these challenges, providing a structured framework within which informants, clinicians and other health professionals could collect standardized information about mental health problems. The various assessments are designed to complement each other, providing framework to elicit and share knowledge about the person. Results from these assessments can then be used along with other sources of information to arrive at a comprehensive case formulation.