Whorlton Hall abuse: Care watchdog publishes report
The care watchdog has released a previously unpublished report on a hospital where it is alleged patients were taunted and intimidated.
BBC Panorama's undercover filming appeared to show patients with learning difficulties being mistreated at Whorlton Hall in County Durham.
In 2015 an unpublished inspection report by the Care Quality Commission (CQC) said it "requires improvement".
A published report a year later gave it an overall rating of "good".
The 2015 report was written by a highly experienced inspector, who left the CQC following a row about the regulator's failure to publish it.
It found inadequate staffing levels, a lack of training and a failure to follow patients' care plans.
When patients made allegations against staff, the report said they were investigated internally and there was no evidence of people learning from the incidents.
The CQC said the issues raised were examined again in a second inspection in 2016, after which the hospital was rated as "good" overall.
It has now released five drafts of the 2015 report, ahead of an appearance at a parliamentary hearing on Wednesday over its regulation of the privately-run NHS-funded unit.
In a statement it said it was undertaking "an independent review into how we dealt with concerns raised by Barry Stanley-Wilkinson, an ex-CQC inspector, in relation to the regulation of Whorlton Hall".
It added: "This review will focus on concerns raised about the draft report prepared in 2015, and how they were addressed through our internal processes.
"It will be for the independent reviewer to report on the handling of our draft reports and it is important not to pre-empt their findings.
"However, we are keen to co-operate with the committee to the fullest extent and so have today shared the following documents."
Following the allegations, seven men and three women were arrested at addresses in Barnard Castle, Bishop Auckland, Darlington and Stockton, and later released under investigation pending further inquiries.