Young people should be allowed to have chlamydia screening through the post, a government-funded researcher says.
People with chlamydia may not have any symptoms
Dr Nicola Low, of the Health Technology Assessment project, said postal testing may reach people not involved with the national screening programme.
Her team tested nearly 5,000 people by getting them to send urine samples or swabs to laboratories via the post.
Chlamydia is the most common sexually transmitted infection, affecting one in 10 sexually active women.
It costs the NHS £100m a year to treat and is sometimes called the silent infection as it is often symptomless but can cause infertility.
Half of the people sent letters took part and researchers said they were confident the results were accurate.
Dr Low, from the University of Bristol, said there needed to be a larger research project into postal screening, but if it proved successful there was no reason why it should not be introduced into the national programme.
"Alongside other methods, it could increase the number of people going through the screening programme.
"People could be sent annual reminders in the posts and send back the samples."
The screening programme was launched in 2003 for under 25s and over 60,000 people a year are screened.
Half of the young people taking part in the screening programme are tested in contraceptive clinics with the rest being seen in young people's clinics, GP surgeries, colleges and prisons.
Dr Low and her team, based at Bristol and Birmingham universities, are looking at various aspects of chlamydia screening, including the emotional and psychological effects and cost effectiveness of screening as part of the Chlamydia Screening Studies (Class) project.
Full details of the project will be published in the autumn, but early findings have shown that postal screening should be considered, Dr Low said.
Some 4,700 took part in the screening after 10,000 people identified from GP lists in the Bristol and West Midlands received letters asking them to participate.
Of the 1,900 men tested, 5.3% were diagnosed with the infection, while 6.2% of the 2,800 women were positive.
Researchers said the results were in line with what you would expect from the population group and, therefore, were likely to be accurate.
Val Buxton, acting chief executive of Brook, the sexual health charity for young people, said postal screening could be a "good way of reaching those who might not have realised they were at risk" or who were reluctant to use health services.
But she added: "It's also crucial that those who do get a positive result can get quick and easy access to treatment."
A spokeswoman for the Department of Health said they would consider the implications of the research.
"This is a flexible programme which can be adapted to include new innovative ways of screening."