The 35-year-old, who starred as feisty Jude Kocarnik in the BBC series, collected her BSc at the Royal Festival Hall in June. She says her new qualification could lead to a new career.
"I already work as a volunteer occupational therapist in a psychiatric unit," she says. "The work really fascinates me and I am beginning to think of giving up acting and training to be a psychiatric nurse. This degree is a great start to doing that. If I succeed, I'll be able to see if I was acting the role accurately."
Lisa, who is also known to younger TV viewers as scruffy writer Cam Lawson in the BBC children's series The Story Of Tracey Beaker, began studying with the OU over 10 years ago. "I never liked the idea of going away to university, so I never did," she says. "I loved acting and I wanted to do that instead.
"But from when I left school I always wanted to do a degree in psychology, which has always interested me. I always liked the idea of the OU and I would always watch the TV programmes, but I struggled to find the time, especially when I got the role in Casualty. My student record shows I started the same course about three years running during the 1990s because I kept signing up and then wasn't able to do the work!"
In fact, being unable to concentrate on her studies was one reason Lisa left the hospital drama in 1997. "I needed more time and we worked so hard on that show that I never had the opportunity. When I got that time, I got into my studies."
Six years' hard work later, Lisa was delighted to attend her graduation ceremony - but it's not the end of her OU journey. She says she agrees with Will Swann, the OU's director (students) who, in his closing address at her graduation ceremony, had said he thought Open University learning was addictive. "I'm really hooked," says Lisa. "I'm going to see how I find the experience of working in the National Health Service, and if that goes OK I would like to do an MA. But I've already found I haven't been able to stop studying. I finished my degree in December but I'm already halfway through an OU creative writing course!"
Lisa readily acknowledges OU study is hard - "the most difficult thing is the constant self-motivation" - but some aspects of her degree courses came as a pleasant surprise. "When I first signed up, I dreaded having to go to summer schools," she says. "If I'm honest, I thought they'd be full of weirdos! But I met so many fantastic people and I thoroughly enjoyed going. Summer schools are brilliant!"
As an actor working sometimes irregular hours, Lisa also appreciates the flexibility of OU study. "Some days you are working flat out continuously, and at other times you can have a whole run of days off in a row - I looked forward to those times, because I knew it would be easier to study without distraction."
But the acting may soon come to an end. "I don't go for the spectacular high-profile roles, but parts that challenge and interest me," says Lisa. "There aren't so many roles out there for women over 40, so there are likely to be fewer opportunities."
She seems more excited about the prospect of her new career - and carrying on her studies. Certainly, the graduation ceremony has given her a taste for more such days. "What a fantastic day. A lot of the time when you're studying, you're on your own. But seeing all the other graduates, I really felt like I was part of something. And to see people from all walks of life, of all ages, getting their degrees was wonderful. The OU's an excellent place, so egalitarian. It doesn't matter where you come from, the Open University gives you an opportunity. I think it's brilliant."
Richard Vaughan finds OU study ideal for fitting around his unusual work schedule as Britain's number one badminton player.
The 27-year-old Welshman says his constant travel around the world to train and play in tournaments means he spends lots of hours on planes - which is ideal for working towards his BA in international studies.
And Richard, who is training for his third consecutive Olympic Games, is delighted to have found a way to study when he's halfway round the globe.
"It's ideal," he says. "I travel all over the world and can be in, say Asia, for about six weeks at a time, so I can take my OU materials with me. I keep in touch with my tutor via e-mail and I love the flexibility of studying when it suits me."
Richard, from Cardiff, is two years away from getting his BA. He started out studying for a computing degree but switched to international studies. "It fascinates me and teaches me a lot about the places I visit," he says.
He is looking forward to graduating the year before his next major sporting target - the Beijing Olympics in 2008.
"If I have a good run-up to the Games and don't get injured I could do well," says Richard, a Commonwealth Games bronze medallist who has been ranked as high as seventh in the world. "I reached the last 16 in Sydney in 2000, and although I had a hip operation in the run-up to Athens last year I reached the last 16 again. If all goes to plan in Beijing, I'd like to get to the quarter-finals - and then I'll be only one match away from a medal."
And that would probably have been Richard's last Olympics - but the decision to award the 2012 Games to London may tempt him to keep playing at the top level for a little longer. "It would be great to play at an Olympics in front of a British crowd," he says. "I'll be 33 then, which is quite old for a badminton player but I hope I would be able to play in the doubles.
"London is going to put on a fantastic Games," he says. "The bid was excellent. I know some of the leading players in the Paris bid, and they were convinced that they were going to win.
"But London's bid was outstanding and it's going to put on an outstanding Games. I really want to be part of it!"
To follow Richard's Olympic progress, log on to www.richardvaughan.netReuse content