This means that the value of the measured production rate could be off by as much as ±35%. So, if the scientists measured a top-quark production rate of, say, 100 events, the true rate could be anywhere between 65 and 135 events, based on the uncertainty.
They suggest that the third run of LHC would result in more accurate measurements. Hopefully, the result of the current and future top quark experiments will reveal valuable insights into QGP.