“I was photographed with a big perm and shoulder pads and people think that’s who I was.“

Barbara Dickson believes being successful from ‘75 to ‘85 was a double-edged sword.

“It was great at the time but sometimes it’s very difficult to make people see you in a different way.”

Barbara Dickson may be remembered for her pop hits in the 1970s and ‘80s; for the success she had with the Andrew Lloyd Webber and Tim Rice numbers in the ‘80s; or for being the original Mrs Johnstone in Blood Brothers but, in a musical career spanning 50 years, that decade was just a tiny, albeit very bright, spark.

Barbara started out singing in folk clubs in her native Fife in 1964 and was happily doing the rounds of the British folk circuit until the early 1970s, singing and playing her guitar and making a comfortable living from it.

“I’d been a professional folk musician for six years and was quite happy doing that,“ says the 67-year-old, who starts her latest UK tour at the Watford Colosseum in February.

But then she bumped into an old friend from the folk circuit and the course of her career took a dramatic change.

The emerging Liverpudlian playwright Willy Russell was looking for a singer to perform Beatles songs in his new play about the legendary group, and he remembered Barbara.

“I didn’t expect to become a household name because of John, Paul, George, Ringo... and Bert,“ says Barbara, who was still only in her 20s when the play was staged at Liverpool’s Everyman Theatre in 1974, with a cast that included Anthony Sher, Bernard Hill and Trevor Eve, and then transferred to the West End. “To me, it was just a one-off, I’m not really a musical theatre person – I don’t dance and I didn’t do any acting.“

But the play was a success and Barbara was spotted by impresario Robert Stigwood, who signed her to his label, RSO Records – and her pop career was born.

She had hits from the mid-1970s, beginning with 1976’s Answer Me, a guest residency on The Two Ronnies, hits with Andrew Lloyd Webber and Tim Rice songs such as Another Suitcase in Another Hall and I Know Him So Well, gold albums, regular TV appearances, sell-out tours, and an award-winning appearance in Willy Russell’s Blood Brothers – all of which established her as one of the UK’s most popular and successful female vocalists.

“I wasn’t seeking fame and fortune, I just wanted to make a living and play good music – and that’s actually still what I want to do now,“ continues Barbara, who started learning the piano aged five and the guitar aged 12. “I would absolutely have just carried on round the folk scene.“

During her commercial heyday, Barbara never fully let go of her beloved folk music.

“I did continue to sing some folk songs as part of my set, and I used to sing as serious a set of songs as I could get away with,“ she says. “But being a pop star it was kind of difficult because you were attracting an audience who’d come along because they’d seen you on Top of the Pops.“

From the early 1990s Barbara began to move away from pop and back to her folk roots, and was delighted that many fans made the move with her.

“I meet people after the shows and there are people who’ve been coming for years. It’s really nice to see them and know they’re interested in my development. But there’s a huge cross-section of people at my shows – some people in their 30s who’ve been switched on to me by their parents, people who were interested in from my musical theatre or my TV work, people from my pop days.“

Barbara can’t wait to get back on the road again to meet her fans old and new, and play “some old things that people will expect me to sing“ as well as new music from her latest album Winter, which came out in December.

“The show is a microcosm of what I do now,“ says Barbara, who aims to go out on tour every 18 months to two years. “The new songs, some old ones, and rearrangements of one or two things. That’s the very essence of my live work – I don’t come on in a long frock and sing a pile of songs from the ‘70s and ‘80s. I’ve not wanted to keep doing the same thing now that I did then, there doesn’t seem to be any progress in that. I’m a working musician and have been since the ‘60s, and I continue to evolve now.

“However, I do do Caravans, Another Suitcase in Another Hall, and Answer Me, which were all milestones for me – I take those forward with me.

“But it’s important for me to move forward. It’s a voyage of discovery. If I’m allowed to, or if I keep in good health, I’ll continue to do this for as long as I can. It’s a lovely thing to do for a living.“