Safe staff levels 'should apply to NHS and care sector'
Safe staffing levels should be extended beyond nurse numbers in England to include midwives and doctors, especially in A&E units, MPs say.
The Health Select Committee also suggested breaches should automatically trigger inspections by the regulator.
Currently ministers have ordered only nurse staffing levels to be routinely monitored and published.
The system - ordered in response to the Stafford Hospital scandal - comes into place in April.
But the cross-party group of MPs said there was no reason why it should not be extended across the NHS and social care systems.
Committee chairman Stephen Dorrell said: "This should be applied across the delivery of health and care - doctors, midwives, practice nurses and social workers.
"Part of the difficulty in A&E is driven by the fact there are not enough doctors of all levels."
Figures from the College of Emergency Medicine show that there are shortages among trainees, middle-grade doctors and consultants.
For example, the college recommends 10 consultants for each A&E unit and 16 for the largest ones. But the current average is just below eight.
Labour MP Barbara Keeley, who is also a member of the committee, added: "Staffing levels are absolutely fundamental. It is ludicrous not to be transparent about something that patients and their families can see every day."
The suggestion was put forward in a report that looked at the progress the Care Quality Commission has been making.
The regulator has been under fire ever since it was created in 2009.
Reports in the past by the National Audit Office and the Health Select Committee have criticised the Healthcare Commission for a "tick-box" culture and failing patients.
But the MPs said the regulator had a "renewed sense of purpose" since a new chairman and chief executive were appointed in 2012.
Last year the leadership appointed three new chief inspectors, covering hospitals, GPs and social care to herald an era of tougher, more specialist investigations.
It has also sought to recruit more inspectors - although it is still 150 short of its 1,100 target.
Mr Dorrell said: "We are not yet saying all the challenges have been met. But by and large we agree with the management of the CQC about their objectives and we endorse them."
CQC chairman David Prior said: "This report marks an important milestone."