Don't overgeneralize: The page you linked explicitly lays it out. Corruption Perceptions Index. Each word is important. In addition, think tanks have biases and TI is no exception. Do you think that the "experts and business people" they interview to calculate CPI have interests which may align more or less with different nations?
In any case, I opened by admitting my perception of the United States is as a more transparent actor than China. Still doesn't make a dichotomy.