Electroconvulsive therapy has been around for more than 50 years, yet information on how it works is scant and treatment data is under-recorded. John Appleby reports

The first experiments with electroconvulsive therapy were conducted in the 1930s by the Italian psychiatrist Ugo Cerletti. Inspired by electric shock devices used by slaughterhouse workers to stun pigs, Cerletti developed the first machine to deliver electric shocks to humans.

During the 1940s and 1950s, and before the development of drug treatments, ECT was widely used. Although seen by practitioners as a valuable and effective treatment for limited illnesses, at best ECT is viewed by the public as unpleasant (although perhaps necessary) and at worst a barbaric violation of human rights. There are many medical treatments which can appear 'barbaric' and which can involve the use of potentially fatal substances or techniques, but to many ECT seems a particularly violent and crude intervention. Ernest Hemingway's observation concerning his loss of memory following ECT - 'It was a brilliant cure but we lost the patient' - reinforces this view.

Although not unique to ECT as a medical treatment, the lack of a convincing scientific explanation as to how it works no doubt contributes to unease about its use. Memory loss, the notion that patients feel 'punished' (and therefore 'behave'), as well as the stimulation of neurotransmitters, are some suggestions for the 'mechanism' of ECT.

In England, before 1990, basic statistics - essentially counts of treatments given - were collected on a regular basis. However, as part of a drive to reduce the data collection burden on the NHS, this was stopped. Although it was thought that the hospital episode statistics system would provide similar data, in the words of the Department of Health, HES turned out to be 'randomly under-recording treatments'.

It also transpires that HES recorded less than a quarter of all inpatient activity involving ECT. Apparently, and somewhat surprisingly, many trusts did not realise that ECT should be recorded as an operative procedure, and mental health trusts which did not carry out operations did not know that there were operative codes relating to ECT.

The lack of ECT data prompted the DoH to conduct a survey to establish some basic information on its use in England. Carried out over a three-month period last year, the survey suggests that annually around 66,000 treatments are given in England to around 11,000 people. A significant majority of patients were women (68 per cent) and more than 40 per cent of all those treated were aged over 65 (with one person aged under 16 also receiving ECT).

Recent trends suggest that the number of treatments given have halved since 1985, but given the ten-year data gap it is unclear whether this suggests a continuing decline or a stabilisation. A report produced by the Royal College of Psychiatrists last year identified a number of shortcomings in the way ECT was being administered in England and Wales.

It seems that there is still a lot of work to be done.