Using interactive websites can help people with long-term conditions that include depression, heart disease and HIV/Aids, a study has found.
Online support helps people with illnesses cope, the review found
A review by University College London found sites with information alone were of little use.
They said people benefited from sites which also linked them to people with the same condition, or supported them in other ways.
The conclusions were backed by doctor-patient groups.
The UCL researchers looked at 24 studies involving 3,739 participants who all had chronic (long-term) health conditions.
They looked at these people's use of interactive computer websites and programmes, which contained information services plus online support groups, chatrooms, or tailored advice based on a person's details, affected people with such chronic diseases.
Interactive sites were of greater benefit to people than those with information alone, or not using sites at all.
The researchers found such sites have largely positive effects on users, making them feel better informed and more socially supported.
Overall, people who used such sites appeared to see improvements in the way they looked after their health and in their clinical condition.
They also had improved self-efficacy - a person's belief in their ability to carry out potentially-beneficial actions.
Dr Elizabeth Murray, who led the Cochrane Review team, said: "People with chronic disease often want more information about their illness and the various treatment options available.
"They may also seek advice and support to help them make behaviour changes necessary to manage and live with the disease, such as changes in diet or exercise.
"Computer-based programs which combine health information with, for example, online peer support may be one way of meeting these needs and of helping people to achieve better health."
She said many of the sites which had been studied had been set up by academics for the duration of the research.
But she said her team's findings offered people a guide as to what kinds of sites to use.
Larger studies needed
"If the site includes support, such as chat rooms, that's what you're looking for.
"Who runs it is also important - is it a respectable body? And if there is advertising, that can be a warning sign, because then you wouldn't know whether or not the support being offered was biased or not."
But she said larger scale studies were needed to confirm her team's findings.
A spokeswoman for Developing Patient Partnerships said interactive sites were a weapon in the armoury that helped people with chronic health problems manage their conditions.
The UCL group were looking at the potential benefits of interactive websites for the second time.
Their first review, published last year, which found websites did not have benefits, was withdrawn after it was found a statistical error had been made in its preparation.