Dual VVT - i (variable valve timing — intelligent) provides continuous, variable control of both the intake and exhaust valves to optimize performance and fuel consumption. (greencarcongress.com)
Their diet is the biggest health variable controlled by you, their guardian, and is crucial to their well being! (wagnwash.com)
With other variables controlled, an inverse age at marriage - instability relationship persists; and differences in marital stability by education appear largely attributable to differences in age at marriage by education. (jstor.org)