Around 7 per cent of acute spells are priced incorrectly due to clinical coding errors, a study has found.

A Department of Health-commissioned study of 50 acute trusts found that on average 7 per cent of providers’ spells of care were incorrectly priced due to inaccurate coding.

At one trust the error rate in audited care spells was as high as 45.8 per cent. The best performing trust was found to have an error rate of 1.1 per cent.

Increasingly tight deadlines for those working in coding departments, inexperienced staff and vacant posts were found by auditors to increase the risk of coding errors.

The study, carried out by Capita CHKS, audited 8,990 episodes of care, amounting to £15.3m of NHS spending.

Auditors also said that the poor quality of paper case notes which form the source for many coders was a “persistent cause for concern”.

“When paper case notes are in a poor condition, it slows the coders’ work and makes it difficult to extract the right information from them,” it said.

“To hit deadlines coders often rely on discharge summaries to clarify diagnoses and treatments. However the information in the discharge summaries is often poor and incomplete, resulting in errors.”

Providers were found to have “consistently under-recorded” treatment episodes for patients with co-morbidities.

The report states:  “Despite being an area of concern for commissioners, our audits found that providers were consistently under-recording comorbidities.”

The report recommends areas in which senior managers should review the quality of their clinical coding.

These include complete and consistent discharge summaries; IT systems;  clinical engagement; and regular analysis of coded information.

A Department of Health spokeswoman said: “Our priority is to ensure patients receive the best possible care and the NHS receives a fair reimbursement for the services it provides to patients.

“Despite continued improvements in the accuracy of coding in the NHS, there is room for further improvement and Monitor will be looking at this carefully.”

A Monitor spokesman said: “Accurate clinical coding is important to Monitor because it drives improvements in the quality of case mix information which is used to determine the National Tariff for NHS funded services.

“In July 2014, the Department of Health contract with Capita for the national programme of case mix and pricing audits was transferred to Monitor. 

“We intend to audit 75 acute trusts by March 2015. The first audit started on Tuesday 28 October.

“Monitor intends to review compliance with previous recommendations. We intend to publish a report on the findings of our audit programme next summer.”

The audit was carried out between September 2013 and March 2014, and analysed 40 trusts previously identified as “at risk” and 10 selected at random.