In 1988, the AJCC and the UICC, in an effort to standardize systems for staging, recommended jointly a four-tier system in which two changes were of note.¹³ First, in this revised system the size of a lymph node affected by metastasis need only be 3 cm, rather than 5 cm, in order to qualify as Stage IV. Second, in Stages I and II, Breslow's thickness trumped Clark's level when any discrepancy existed between them. No reason was given for downsizing a lymph node that harbored a metastasis; the reason for the triumph of Breslow's thickness over Clark's levels was said to be evidence statistically. The system devised jointly was revised again in 1992¹⁴ and then again in 1997,¹⁵ at which time it was propounded that Breslow's thickness should not automatically override Clark's level, but rather in situations where there were discrepancies between them, the figure associated with the least favorable prognosis should prevail.