The former Criminal Records Bureau (CRB) has now been replaced by the Disclosure and Barring Service (DBS). The transfer of records and procedures is ongoing - the old CRB forms are still being used.
There have been 2 radical changes, one, following the Soham murders, increased the scope of a disclosure, the second, following the Government's review of the CRB scheme.
Rather than type an attempt at an answer to your question, can I refer you to another thread in which I did cover much of this ground? Here: CRB checks (now Disclosure and Barring Service)
I'm unable to agree with some of the earlier posts in this thread, specifically those by Class_317There are reasons, and Chief Constable considering a conviction for a (car) driving offence while studying a request in respect of an applicant for a (train) driving position might, just might, consider that the 2 have some relevance to each other; but please note the filtering procedures which will be applied when considering a request.
Would a basic disclosure still be the same though?