Mr Cho analysed the jitter and shimmer - the acoustic characteristics of voice signals that are used to determine voice pathologies - in Mr Kim's words.
He was also able to monitor the noise-to-harmonics ratio and the "energy" in his voice, The Korea Times reported.
And although the results indicate that Mr Kim's lungs and heart are apparently healthy, deviations from normal figures show that he has a kidney complaint, Mr Cho said.
"At the least, the samples show that his kidneys are weaker than his other organs", he told the newspaper.
Mr Cho's diagnosis is unlikely to come as a surprise as the North Korean leader is visibly overweight and a slight limp was still visible when he approached the stand to deliver his speech.
As far back as 2014, Mr Kim was shown on state television walking with a pronounced limp and he disappeared from public view for several weeks from September of that year.
He subsequently reappeared hobbling with the aid of a walking stick. One South Korean newspaper claimed that Mr Kim's disappearance was because his ankles had fractured under his own weight.
Believed to have turned 36 earlier this week, Mr Kim has put on a significant amount of weight since he inherited North Korea after the death of his father, Kim Jong-il, in December 2011.
As well as the country, Mr Kim appears to have inherited his father's health problems as well as his love of the good life. Known for his appreciation of expensive French brandy and fine cuisine, Kim Jong-il's sudden death has attributed to high blood pressure, heart disease and diabetes.
The original article was published in the Telegraph.
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