Doctors have called on the Competition Commission (CC) to expand the private healthcare market study to include the operations of private medical insurance (PMI).
They urged a full investigation of claims by insurers of significant consultant fees shortfalls and questioned the lack of transparency in PMI policies at the point of sale.
Health insurance brokers also welcomed the announcement that, pending an eight week consultation, the Office of Fair Trading (OFT) will refer the private healthcare market to the CC for further scrutiny.
They echoed practitioners' concerns around insurers' clinical data and around fee transparency while also arguing for the use of hospital and treatment networks to be examined.
The Federation of Independent Practitioners Organisations (FIPO), which represents doctors and other clinicians and organisations involved in private practice, said the OFT's decision undermined insurers' claims.
It said the body would assist in clarifying the causes of some ‘informational asymmetry' issues identified and press for the Commission to involve the major PMI providers "directly and fully in its market investigation rather than on the narrow arms length FSA linked basis of this OFT market study".
Richard Packard, deputy chairman of FIPO, argued the issue of short falls on consultant fees can only be properly reviewed if data from all insurers is used in a full investigation.
"FIPO believes that actual average shortfall is insignificant, around 1.5%, and that the lack of transparency at the point of sale for PMI policies has some bearing on the issues that arise.
"We are delighted the OFT has re-enforced the importance of the role GPs in working with patients in the selection of specialist consultants. Fee estimates and costs are important but any choice from a list based on price alone cannot be in a patient's interest.
"It is important that there is adequate and comparable information available to patients and their GPs when making their choice of specialist," he added.
He also targeted insurers' attempts to encourage people to use NHS services where possible and restrict access to only approved consultants.
"The OFT has highlighted as misleading the claims by certain insurers to PMI policyholders that decisions are based on a ‘unique level of information'.
"Moves by insurers to restrict choice of consultant based on costs alone - in the absence of any reliable clinical data - must be held to scrutiny."
The Association of Medical Insurance Intermediaries (Amii) added its voice to calls for a subsequent wider investigation including PMI providers' practices by the CC.
Andrew Tripp, chairman of Amii, said: "We want to see greater transparency around benefit fee limits for consultants and anaesthetists.
"In the UK access to transparent and competitive markets should be fundamental rights for consumers seeking private healthcare, this is extremely important, especially now, when greater pressures are being put on NHS spending raising the important role the private healthcare market has to play.
"We believe there should be a clear distinction between those broad-based hospital networks and treatment networks, which may be more restrictive than the general hospital list that the policyholder has bought into," he added.
Tripp also called for existing policyholders being given the choice to "opt out" of a treatment network when introduced and for insurers to share with intermediaries and policyholders the quality data they are using to establish these treatment networks.
