The 26-year-old is one of Britain's key medal hopes at the World Championships but has yet to claim a podium finish at a major global outdoor event.

She wants no repeat of the mistakes at Beijing 2015, Rio 2016 and London 2017.

"I have to be at my best if I want to win," said the Liverpool athlete.

"I hope so [that mistakes are over]. Obviously, you never know with the heptathlon - there are so many different opportunities to have those slip-ups.

"You do get bad performances and good performances. Unfortunately, with the level the event is at at the minute, a slip will cost you medals - even if it is just a small one - because you have to be at your best."

Johnson-Thompson finished well down the heptathlon field at the 2015 Worlds after three fouls in the long jump, while below par performances in the shot put and javelin cost her a medal at the Rio Olympics in 2016.

At the 2017 Worlds, Johnson-Thompson said she "threw away 200 points" by only clearing 1.80m in the heptathlon. By comparison, when competing in the individual high jump event, she cleared 1.95m.

The fortunes of Johnson-Thompson began to turn last year when she first won the world indoor pentathlon title, before adding Commonwealth heptathlon gold and European silver.

The European gold medallist in Berlin was the seemingly immovable Nafissatou Thiam, who is also the current world and Olympic champion.

At the Birmingham Diamond League meeting, the Belgian went further than Johnson-Thompson in the long jump, which is one of the Briton's favoured events.

"I am just trying to make sure I am consistent every time I step on to the track and that my preparation and also my training is consistent," Johnson-Thompson added.

"All I can really do is be consistent across the event and hope for a big performance here and there and see what happens."

Denise Lewis, Britain's Sydney 2000 Olympic heptathlon champion, told BBC Sport it will be "nip and tuck" for the title all the way between Johnson-Thompson and Thiam.

"We have to assume Thiam is getting better, although we know she has an elbow problem," Lewis said. "But there is nothing to suggest she isn't in tip-top form.

"It'll be nip and tuck all the way. If Kat believes and takes her opportunities there could be a little upset, but she will have to avoid any mistakes. Someone will make an error though and she has to be ready to pounce."

Day one of the seven-event competition starts with the 100m hurdles at 15:05 BST.