@blue25 There are some very dubious organisations out there, making money for providing diagnosis without proper assessments.
@NotAnotherJaffaCake To be honest I have seen some private diagnoses which were appalling - no evidence to support any diagnosis
Are you both talking about ASD diagnostic assessments? Because I do not recognise what you are saying.
I have worked in in the 'field' of ASD since 1985 in 3 different counties. I have worked in the NHS, in LA maintained schools and in advisory roles within the LA. I have read hundreds of diagnostic reports, both private and NHS. I can honestly say I have never come across a child who has been diagnosed as autistic who was reassessed at a future date and found not to be.
Conversely, I have known a significant number of children with atypical and complex ASD profiles, who slipped through assessment and who have only been diagnosed at later assessment when their needs were more clearly identifiable or who had subsequently been assessed by specialist clinicians with more in depth experience of the spectrum.
As I'm sure you know, there are a variety of diagnostic tools that can be used. Not every clinician is trained in all possible assessments.
Certain diagnostic 'tests' are more sensitive to identifing some ASD profiles than others. e.g. the DISCO is more likely to pick up a PDA type profile than the ADOS. It doesn't make one test better than another, but can explain why in one assessment the threshold for diagnosis is not met, but using a different diagnostic tool the diagnostic threshold is met.
I have no idea where these backstreet ASD assessment clinics are that you can simply pay for a diagnosis. But if you know of them then report them!
If, however, you are talking about the quality of the reports received from professionals, well I can accept that these may be "appalling".
I have read many brief, abrubt, unhelpful reports in my time and have a number filed away from professionals working with my own DD!
But a crap report doesn't equate to an unsafe diagnosis.