This means he will only be able to defend one of his two Paralympic titles due to the T13 200 metres having been removed from the programme for next year's Games in Rio de Janeiro.

Smyth, winner of the 100 and 200 metres T13 double at both Beijing 2008 and London 2012, was surprisingly shifted into the T12 category following a classification review ahead of last year's European Championships in Swansea, where he still won double gold.

He still holds the two T13 world records of 10.46sec for 100m and 21.05 for 200m.

The T12 division is for athletes with stronger impairments, with Smyth having been re-classified to that level following a supposed progression of his visual impairment, Stargardts disease.

The IPC have now acknowledged, however, that a re-test may have been the best course of action last year, with no further review now scheduled until 2019.

“When Jason Smyth was classified ahead of the European Championships in 2014 he was found to be on the borderline of the T12 and T13 classes," an IPC spokesperson said.

"All of the results of the assessment placed him in the T12 class, he was however placed under review status.

"The review was conducted this week and his results were again borderline but all were in the T13 class so he was moved back.

"Vision impairment tests can be influenced by a number of environmental characteristics.

"As last year’s result came as a surprise to all concerned, the IPC acknowledges that in retrospect it should have asked Smyth to undergo a second classification at that time.”

Smyth, who earned the world's fastest Paralympian tag by winning a special cross-classification 100m race in Rio de Janeiro last month, coinciding with Paralympic One Year to Go celebrations, has already announced how he will only compete over 100m in Doha as the longer race is set to clash with his wife giving birth.

He is pleased the classification system is now resolved although disappointed he will now only have one chance to claim gold next year. 

“It was a surprise to me last year that I had been moved to a T12 and was difficult to deal with, so I’m pleased that my status as a T13 has been clarified and I won’t need another review until 2019," he said.

"However, it is disappointing that I definitely won’t have the chance to defend two of my Paralympic titles in Rio as the T13 200m has been removed from the list of Rio medal events by the IPC.

"That said at least I can put all my energies in the 100m and continue to try and run faster and bridge the gap between Paralympic and able bodied sport.”

More than 1,400 athletes from 100 countries are set to compete in 214 medal events in Doha, with the Championships set to be held in the 12,000 capacity Suhaim Bin Hamam stadium in the Qatar Sports Club.

The 100m T13 competition is set to begin on Friday (October 23) with the final the following day.

Classification changes remain a major challenge across Paralympic sports, with the IPC having said this month that the alleged intentional misrepresentation during the classification evaluation process of athletes "is in grave danger of undermining the credibility" of swimming and "overshadowing the performances" of the sport’s athletes.

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October 2015: Four-times Paralympic champion Smyth to skip 200m at World Championships with wife due to give birth
September 2015: Smyth crowned world's fastest Paralympian with victory in race to mark One Year to Go until Rio 2016
September 2015: Sprinters vying for title of world's fastest Para-athlete as part of Rio 2016 One Year To Go celebrations
August 2014: World and Paralympic champion Smyth completes double at IPC Athletics European Championships
August 2014: Peacock wins duel and Smyth brushes aside reclassification at start of IPC Athletics European Championships