A site would also bring help to people who currently keep any bad experiences to themselves or only complain to their friends, which hits the image of the NHS and does not help it to put things right, says Neville Vincent, chairman of the BCS London Medical specialist group.
Vincent sees a need for a "non-threatening" way for patients to record their experiences.
"Satisfaction surveys have been tried in some NHS organisations but there is no uniformity over the country," he says. "In addition, anything official may be regarded with suspicion."
A good national Web site, more easily accessed than official complaint channels, could help overcome such issues.
"Some patients are fully aware of the quality of care that they should receive and make their views known if they are not dissatisfied. But the vast majority are probably more reticent," Vincent says.
He points out that complaining can drain energy and cause anxiety at an already stressful time. People will often even sympathise with staff who are under strain themselves.
"I believe that the moment often passes, and determination to complain wanes with the passage of time," Vincent says. "Any dissatisfaction is then expressed in conversations with family, friends and neighbours, leading to a worsening public impression of the NHS."
If patients do complain later, perhaps to their general practitioner, they may focus on one incident rather than on the quality of care as a whole.
"I suspect that only the most serious issues are taken any further by the person's GP, and that a wide range of dissatisfaction at the Patients Charter level is shrugged off," Vincent says.
He proposes that the BCS Health Informatics Committee, which co-ordinates the work of the five specialist groups in the medical field - and runs an annual conference and exhibition that attracts 5,000 visitors - could promote the idea of a Web site.
The site could be run by an independent agency and perhaps sponsored by some of the many health charities.
The BCS Health Informatics Committee could consider funding initial work to get the site going.
Universities with health research units might be interested in running the site and analysing and publishing the results.
Vincent is currently gathering together views on the idea.
He is at firstname.lastname@example.org