Patient reported outcome measures have not driven expected improvements in treatment during their first three years and do not support claims the NHS is treating too many patients, researchers have found.

A team from the London School of Hygiene and Tropical Medicine reviewed the first three years of PROMs data which captured responses from more than 50,000 patients who underwent groin hernia repair, varicose vein surgery or hip or knee replacements.

They were looking for evidence the publication of the data had led to improvements in the outcomes reported by patients, a reduction in variation between providers, and clinicians making more appropriate referrals, indicated by an increase in the severity of patients being treated.

However, on all counts “little apparent impact” was found by the study, published in the Journal of Health Services Research and Policy.

PROMs results are compiled by surveying patients before and after surgery. They are asked a series of questions, which include condition-specific questions as well as others covering general health.

Nick Black, professor of health services research at the school’s department of health services research, said it was unsurprising the data did appear to have had any impact on behaviour so far.

Presenting the findings at the King’s Fund last week, he said the time lag between the collection and the publication of the data and its poor presentation meant it had been difficult for clinicians and managers to use in a meaningful way.

When PROMs were introduced in April 2009 they were expected to find a significant proportion of patients were reporting little improvement in their health following their procedures. It was suggested millions of pounds worth of procedures were being carried out inappropriately.

However, despite finding a four-fold difference in rates of hip and knee replacement between the highest and lowest primary care trusts, the team found patients in the PCTs with highest rates of surgery were not significantly less in need of surgery than patients in the PCTs with the lowest rates.

A separate paper on this issue is due to be published in the Journal of Public Health.

Professor Black told HSJ there were “no grounds to suggest we should start cutting the amount of surgery we are doing.”

He added: “The data suggests that far from there being inappropriate, unnecessary surgery we are probably still below the level of need.”

He said PROMs still had great potential but the NHS needed to move on from the “initial vision” that they were only useful for comparing providers to considering how they could be used to address “important issues” such as the management of long term conditions.

In some places in Europe patients with long term conditions are asked to fill out a PROMs survey on a regular basis and only if there is a marked difference in the score will they have contact with clinicians.