I’m a professor of clinical psychology. Here’s everything you need to know about ECT

Michael Jackson ’s daughter, Paris, recently revealed that she had undergone nine rounds of electroconvulsive therapy (ECT) to treat severe depression .

In the interview, Jackson said that although she felt the treatment “was working”, she said getting “shocked once a month for the rest of my life” wasn’t feasible for her.

ECT involves inducing a seizure by applying electricity to the head under general anaesthetic. Each series of ECT involves between six and 12 treatments over a period of two to four weeks.

ECT is primarily used for depression, but is also given to people diagnosed with schizophrenia , catatonia (a condition where people exhibit abnormal movements and behaviour) and bipolar disorder. The National Institute for Health and Care Excellence recommends that ECT is only used in extreme circumstances such as when a patient is suicidal and when other treatments have failed.

Some people think that ECT was abandoned long ago, but 2012 data estimated it was given to at least a million people annually, including about 2,500 in England according to 2019 estimates. Recipients are predominantly women and older people.

ECT has been controversial since it was first introduced in 1938, and remains debated today.

The gold standard for assessing a treatment’s effectiveness are randomised controlled trials. These directly compare a treatment against a placebo. In ECT studies, one group receives ECT, while the placebo group are given “sham ECT”, where they’re put under general anaesthesia but the electricity is withheld.

There have only been 11 placebo-controlled studies of ECT for depression. A review I co-authored in 2019 assessed the quality of those 11 studies. My colleagues and I found that all 11 were very small, were flawed in various ways and failed to comply with today’s methodological standards

Four of the 11 studies found ECT significantly superior to sham ECT at the end of treatment. Five found no difference between real ECT and sham ECT. Two studies found that psychiatrists reported a difference but patients did not. There was no robust evidence of effectiveness beyond the day of the last treatment – so there was no evidence of any long-term benefit of ECT.

Surprisingly, the most recent of these studies was in 1985. There have been none for 40 years. So, the honest answer to the question “does it work?” is, nearly 90 years after the first ECT, we really don’t know.

Some studies claim to show ECT performs better than other depression treatments, but a 2017 review of studies since 2009 found that in most of these studies the ECT group was also on antidepressants – making it hard to interpret the results.