['Gold standard', not 'golden standard'].

In medical literature, both 'gold standard' and 'golden standard' are employed to describe a reference test used for comparison with a novel method. The term 'gold standard' in its current sense in medical research was coined by Rudd in 1979, in reference to the monetary gold standard. In the same way that the monetary gold standard allowed for the comparison of different currencies, the medical gold standard allowed for the comparison of different diagnostic tests. Whereas the gold standard was never regarded as infallible, the incorrect term 'golden standard' implies a level of perfection that is unattainable in medical science. Consequently, the correct term should be 'gold standard'.