A new test could provide a better way to identify and prevent cervical cancer , say researchers.
Smear tests can produce unclear results
It detects the presence of the Human Papilloma Virus (HPV) - the cause of most cervical cancers.
Tests on 11,000 women showed the test picked up 97% of significant cervical abnormalities. The standard test picked up just 76%.
Cancer Research UK says the study, published in The Lancet, suggests the HPV test should be used as standard.
Lead researcher Professor Jack Cuzick, of Queen Mary, University of London, said: "Our findings are so promising that a pilot project should now be set up to see how the new test should be integrated into the existing cervical screening programme."
HPV infection is extremely common, but most infections disappear without causing any disease and without the need for treatment. Only when the infection persists can it cause cervical cancer.
The study focussed on how best to use the test's greater sensitivity without over-treating infections that would otherwise be cleared naturally by the body's immune system.
The authors suggest that HPV testing could be the primary screening test and smears would be done (using the remainder of the sample) only in women who tested positive for the virus.
If that smear were negative, the study showed that it was safe to monitor these women by re-testing a year later to see if the infection had disappeared.
Scientists also believe that this approach could reduce the number of women who are needlessly referred to hospital clinics because of false positive smear test results.
Professor Cuzick said: "We have known for decades that Human Papilloma Virus is the primary cause of cervix cancer.
"We now have a test that can very accurately detect its presence.
"It's time to put this knowledge into practice so that women can benefit from these discoveries."
The NHS screening programme recently decided to defer cervical screening until the age of 25.
Professor Cuzick said this decision made HPV testing more attractive - because it would lead to fewer false positives after this age.
Liquid based cytology
Professor Peter Sasieni, who also worked on the study, said another recent decision by the NHS screening programme to introduce liquid based cytology in cervical screening would reduce the number of inadequate smear tests.
The technique provides much clearer samples for experts to analyse.
But he said: "HPV testing offers the best hope of improving the effectiveness of cervical screening.
"The HPV test can be performed on the same sample as is used for the smear test. So there is no need for women with HPV to come back for another test."
Martin Ledwick, senior cancer information nurse for the charity CancerBACUP, said: "Anything that improves the accuracy of screening has got to be a good thing and these results look very promising.
"However, it's worth remembering that cases of cervical cancer have been dramatically reduced as a direct result of the current cervical screening programme.
"So until decisions are made about whether to introduce this technology, it's really worthwhile for women to attend their regular smear appointments."
Julietta Patnick, director of the NHS Cancer Screening Programme, said their were many practical issues which would have to be considered before HPV testing was pilotted alongside the existing cervical screening test.
But she said the NHS was already carrying out research to assess the cost and efficacy of such a move.
"The evaluation results should be available by summer 2007. When combined with the results of other studies, this will provide a clearer picture of the value of HPV screening on a national scale."
All the women taking part in the study were over the age of 30 and 9% were found to carry HPV.
About 20% of women under 25 carry the HPV virus but this drops to 5 per cent by the age of 40.