The Fina process included an official survey of the Wellington Regional Aquatic Centre pool and doping control.
"It's really nice to have the record officially now," said Boyle, a three-time medal winner at last year's world championships and Commonwealth Games gold medallist in Glasgow in July.
"I was really happy with the time because I knew I had done a good swim.
"To have it officially recognised means others think it was a good swim also."
She is the fourth New Zealander to hold a world record.
Phillipa Gower, nee Gould, is the only one of the four to have set long-course best marks, for the 220 yard (200m) backstroke in 1957 and the 110 yard backstroke the following year.
Anna Simcic produced a world best 200m backstroke in Paris in 1992 and double Olympic champion Danyon Loader managed four - the 200m butterfly three times in eight days in 1993, and the 400m freestyle in 1995.
Boyle's focus is on Doha and while she said yesterday she had not fully committed to competing, she will make a final decision in the next two to three weeks.
"I have had a huge year with a lot of travel, and I had a prolonged break that I really needed, and which I think looking at the big picture will really benefit me.
"As defending world champion I only want to go to the championships if I am in the form to produce that sort of form."