The main concerns were staff shortages, accuracy in draft reports, and speed of response to issues raised by whistleblowers, the Public Accounts Committee (PAC) announced in a report published today.
Significant progress has been made since 2012, it said, but "it is behind where it should be, six years after it was established, in that it is not yet an effective regulator".
David Behan, chief executive of the CQC (pictured), said: "We have always maintained that there is more we have to do, in particular with regards to improving the timeliness of our reports and inspecting all health and adult social care services.
“These are not new issues and we have been working hard to improve our performance... What is essential is that we do not take any shortcuts, which could compromise the quality of the important work that we do,” he added.
This comes after it was announced that the CQC fees are set to rise up to seven-fold starting in 2016, either over two or four years (by 2018, or 2020). While the Department of Health pledged a £15 million funding boost for general practice in 2016/17 it is unclear whether funding will be available in the following years.
Currently, there is an “alarming” lack of attention to detail when CQC reports are being prepared, despite them taking too long to be published, Meg Hillier, chair of the PAC explained.
“One NHS Foundation Trust told us staff had identified more than 200 errors in a draft Commission report, including data inaccuracies. The fact these errors were picked up offers some reassurance but this is clearly unacceptable from a public body in which taxpayers are placing their trust.
“If the Commission is to properly fulfil its duty to taxpayers we must see improvements in the way it collects, acts upon and publishes information,” she added.