Is patient coding making hospitals appear better than they are?

Apr 25, 2010

In this week's BMJ, Nigel Hawkes, freelance journalist and Director of Straight Statistics, a campaign for the better use of statistical data, investigates how the way that patients are allocated diagnostic codes by a hospital can have a big effect on a hospital's performance.

It follows two articles published by the BMJ last week arguing that using death rates to judge performance is a bad idea.

It began, says Hawkes, when Mid Staffordshire Foundation NHS Trust was branded "appalling" by the Care Quality Commission, yet was rated in the top ten for quality of care by health analysts Dr Foster in their 2009 Good Hospital Guide. Further investigations into lower than average death rates from broken hips at Mid Staffordshire was put down to "improved coding procedures."

Could such coding changes be affecting Dr Foster's performance evaluations, flattering hospital-standardised mortality ratios (HMSRs) and making hospitals appear much better than they are, asks Hawkes?

Diagnostic coding is used by hospitals to record the conditions suffered by patients admitted to them for treatment, he explains. If a hospital uses an increasing number of codes year by year, it implies that more patients with more severe conditions are being treated. But if the death rate remains constant while the severity index increases, it appears that the hospital is doing better at keeping people alive.

Research by CHKS, a rival health analytical company, shows that the number of codes has been creeping up over recent years, yet crude death rates in English hospitals show virtually no change over the past five years. There is also a big variation in the average number of diagnostic codes per patient from hospital to hospital.

How has this happened, asks Hawkes? One explanation might be the increasing proportion of patients classified as needing palliative care. CHKS figures show the number of deaths coded Z51.5 (the code used for palliative care) was under 400 a month in 2004, but had reached more than 1,800 a month by June 2009.

Patients coded Z51.5 are assumed to have come into hospital to die, so performance calculations make allowance for that. This means that a few heavy users of the Z51.5 code could have reduced their HSMRs from 110 (above average) to 90 (below average) simply by increasing the frequency of use of the code.

Although Hawkes cannot prove that any hospital is doing this, he says "there is no question that the situation is open to manipulation by trusts."

Dr Foster Intelligence, the company responsible for the Good Hospital Guide, believes that HSMRs remain a good measure of the quality of care, if used alongside other measures. CHKS, by contrast, believes that while they may be a useful tool within a hospital, they are unsuitable on their own for comparisons between hospitals while such big coding variations exist.

The clash of evidence between the Good Hospital Guide and the Care Quality Commission embarrassed the Department of Health and a review of the use of HSMRs in England is now underway.

Explore further: New technology that is revealing the science of chewing

add to favorites email to friend print save as pdf

Related Stories

Using death rates to judge hospital performance 'a bad idea'

Apr 21, 2010

Mortality rates are a poor measure of the quality of hospital care and should not be a trigger for public inquiries such as the investigation at the Mid Staffordshire hospital, argue experts in a paper published in the British ...

Minorities, whites get equal care in hospitals

Mar 11, 2008

A University of Maryland study of whether people receive different quality of hospital care because of their race or ethnicity found that when whites and minorities are admitted to a hospital for the same reason, they receive ...

Treatment checklists may cut hospital deaths

Apr 02, 2010

Patient deaths at three London hospitals have been cut by almost 15% after introducing treatment checklists (known as care bundles), finds a study published in the British Medical Journal today.

Recommended for you

Obese British man in court fight for surgery

Jul 11, 2011

A British man weighing 22 stone (139 kilograms, 306 pounds) launched a court appeal Monday against a decision to refuse him state-funded obesity surgery because he is not fat enough.

2008 crisis spurred rise in suicides in Europe

Jul 08, 2011

The financial crisis that began to hit Europe in mid-2008 reversed a steady, years-long fall in suicides among people of working age, according to a letter published on Friday by The Lancet.

New food labels dished up to keep Europe healthy

Jul 06, 2011

A groundbreaking deal on compulsory new food labels Wednesday is set to give Europeans clear information on the nutritional and energy content of products, as well as country of origin.

Overweight men have poorer sperm count

Jul 04, 2011

Overweight or obese men, like their female counterparts, have a lower chance of becoming a parent, according to a comparison of sperm quality presented at a European fertility meeting Monday.

User comments : 0

More news stories

Low Vitamin D may not be a culprit in menopause symptoms

A new study from the Women's Health Initiative (WHI) shows no significant connection between vitamin D levels and menopause symptoms. The study was published online today in Menopause, the journal of The North American Menopa ...

Patent talk: Google sharpens contact lens vision

(Phys.org) —A report from Patent Bolt brings us one step closer to what Google may have in mind in developing smart contact lenses. According to the discussion Google is interested in the concept of contact ...

Tech giants look to skies to spread Internet

The shortest path to the Internet for some remote corners of the world may be through the skies. That is the message from US tech giants seeking to spread the online gospel to hard-to-reach regions.

Wireless industry makes anti-theft commitment

A trade group for wireless providers said Tuesday that the biggest mobile device manufacturers and carriers will soon put anti-theft tools on the gadgets to try to deter rampant smartphone theft.