By Tim Utton         

It's the sort of advice that Patsy Kensit - with three failed marriages behind her - could do with before she takes another trip down the aisle.

Scientists have devised an 'astonishingly accurate' way of working out which couples are destined for divorce years before the first signs of trouble.

The technique, unveiled on the eve of Valentine's Day, analyses conversations between couples to see how well they relate to each other.

The test picks up underlying patterns of speech and behaviour that give strong advance warning of a doomed marriage, according to researchers.

Couples were marked and given a score on their ability to communicate with each other. They got points for good signals including a positive tone of voice, smiles, affectionate gestures and jokes.

But they were also given points for bad signals, such as rolling the eyes, criticism, coldness and mocking.

For example, while a joke in the conversation gained them two good points, scorn gave them three bad ones.

The scores were then compared to give a ratio of good points to bad, which can be used to rate the chance of husband and wife staying together.

The ten-year study involved 700 couples who were observed and videotaped for 15 minutes while they discussed potentially touchy topics such as sex, child-rearing, housework or money.

The couples were tracked every two years, with the mathematical model turning out to be accurate in 94 per cent of cases.

Physiological data on the couples, such as pulse rates, was also collected and analysed. Experts said conversations reflected underlying problems - and that is why the technique provides such strong predictions.

The key was in the ratio of positive to negative comments and behaviour during conversation.

The magic ratio is five positive points to one negative - if it falls below this level, the marriage is doomed.

One of the experts who hit on the formula is Professor James Murray, of Oxford University and the University of Washington in Seattle. He said: 'The maths we came up with is simple, but the model is astonishingly accurate.'

His colleague Professor John Gottman, a psychologist at the University of Washington and director of the Relationship Research Institute in the U.S., added:

'Before this model was developed divorce prediction was not accurate. We had no idea how to analyse what we call the masters and disasters of marriage - those long-term happily married and divorced couples.

'When the masters of marriage are talking about something important they may be arguing, but they are also laughing and teasing and there are signs of affection because they have made emotional connections.

'But a lot of people don't know how to connect or how to build a sense of humour, and this means a lot of fighting that couples engage in is a failure to make emotional connections.

'We wouldn't have known this without the mathematical model. It gives us a way to describe a relationship and the forces that are impelling people that we never had before. It allows us to visualise what happens when two people talk to each other.'

The scientists say the test could give therapists a tool for helping couples overcome problems that might otherwise cause the marriage to fail.

They presented their work yesterday at the annual meeting of the American Association for the Advancement of Science in Seattle.

how do you measure up?

To work out your compatibility rating, ask a friend to monitor you talking to your partner for 15 minutes. You should cover topics such as sex, child-rearing, money and housework and follow the scoring system below.

Couples with a rosy future together will score five or more positive points for every negative one. Those with a lower ratio will divorce, say experts.

positive scores

- Holding hands - 3 points
- Touching - 3 points
- Stroking - 3 points
- Cracking a joke - 2 points
- Laughing - 2 points
- Smiling - 1 point
- Warm tone of voice - 1 point

negative scores            

- Scornful comments - 3 points
- Mockery - 3 points
- Cold tone of voice - 2 points
- Reluctance to talk - 2 points
- Critical comments - 1 point
- Rolling the eyes, expressing disdain - 1 point

©2006 Associated New Media

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