In last week's Data Briefing I raised some issues about the increase in emergency admissions to acute hospitals over the last five years. The increase has primarily been in accident and emergency, and there has been a dramatic increase in the number of patients turned around on the day. While there was no indication of patients being more or less sick, the tariff income per patient has been reducing.

In last week's Data Briefing I raised some issues about the increase in emergency admissions to acute hospitals over the last five years. The increase has primarily been in accident and emergency, and there has been a dramatic increase in the number of patients turned around on the day. While there was no indication of patients being more or less sick, the tariff income per patient has been reducing.

There are potentially at least three effects driving these changes, and a healthcare resource group-level examination finds potential evidence of all three. There is, however, no indication that improved coding plays a significant part in these results. Uncoded episodes account for less than 3 per cent of all non-elective admissions and have stayed relatively steady.

First, is there any evidence of patients being admitted when they might not have been previously? Looking at HRG S16 (poisoning toxic environmental and unspecified effects), the first chart shows an overall increase from about 68,000 in 2001-02 to 94,000 in 2005-06.

The vast majority are through A&E, and the biggest increase is in patients who stay less than a day. And the increase in patients staying less than a day is only visible in A&E; it does not show in GP and 'other' categories. Given the nature of this clinical population, this would be highly consistent with the need for a short period of observation, which may previously have been carried out without an admission.

Second, is there evidence of reductions in length of stay? The second chart shows a similar analysis for HRG E36 (chest pain, for those up to 70, without complications). Again, this shows an increase in numbers admitted through A&E, with the other routes remaining steady, but a rise in the proportion of admissions discharged in less than a day for all categories. This would imply that a more rapid pathway has been developed.

Third, is there a change in route to hospital? The third chart is an identical analysis of HRG M09 (threatened or spontaneous abortion). It shows a small (11 per cent over five years) increase in total admissions, with no change patients staying less than a day. However, it also shows a drop in admissions from GPs and an increase in those through A&E. This is consistent with the hypothesis of GP out-of-hours services suggesting to pregnant women with a bleed that they present themselves straight to hospital rather than being seen by an out-of-hours service.

Paul Robinson is marketing director for healthcare information provider CHKS (phone 01789-761600 or go to www.chks.co.uk).