The regulator in charge of inspecting hospitals and care homes has "distorted" its priorities by focusing on registering providers, according to a report from MPs.
The Care Quality Commission (CQC) was given the function of registering providers of health and social care but this has led to around a 70% drop in the number of inspections to check care standards and safety.
Some 6,840 site visits to providers were undertaken in the six months between October 2009 and end of March 2010, but only 2,008 were carried out in the same six-month period in 2010/11 - a 70% drop.
Care homes for adults received 10,856 inspections in 2009/10 but only 3,805 in 2010/11, a 65% drop.
The average inspector's caseload has also increased from approximately 50 locations each in 2010 to 62 locations in 2011, said the report from the Health Committee.
The report said some hospitals and care homes are not even visited every two years if they are flagged as low risk. Generally, inspections are carried out at least once every two years, with providers submitting annual data to show compliance with a number of standards.
However, the report raised concerns about the quality of that data, which may, for example, fail to flag up excess deaths. It added: "The charity Action on Elder Abuse notes that the routine reviews of providers will not necessarily involve 'face to face' inspection, ie a desktop exercise relying upon information obtained from provider-completed assessments and other documentation that may have been obtained.
"It is difficult to see how assessments can be considered complete, even of apparently good providers, if no visit is made to the premises."
The CQC said in a statement: "The Committee's report highlights the major challenges CQC has faced in merging three existing regulators, setting up a new regulatory model, and registering more than 39,000 provider locations - including previously unregulated sectors - against aggressive Parliamentary deadlines and with a 30% budget reduction.
"We know registration has been a difficult process for everyone involved, which is why we asked the Secretary of State to delay registration of GPs by a year to allow us to improve the way we do it - and to allow our staff to dedicate more time to inspection. Inspection figures are now rising rapidly again - in Q1 (April-June) of this year we published 2,527 inspection reports on NHS and social care providers - this compares to 886 reports published in Q3 of 2010/11, when we were still in the process of completing registration of all 24,000 social care locations."