Original sentence: A double-blind study published in the medical journal Aviation, Space, and Environmental Medicine found no detectable effect of aspartame on pilot performance.In the early 1990s, anecdotal concerns were published alleging that a few pilots who drink diet sodas containing aspartame could be more susceptible to conditions ranging from flicker vertigo to gradual loss of vision
Edited sentence: A 1991 study published in the medical journal Aviation, Space, and Environmental Medicine reported that there were anecdotal concerns about aspartame and the cognitive performance of pilots; however, its double-blind study found no detectable effect of aspartame on pilot performance.In 1992, the US Air Force magazine Flying Safety published an article warning that a few pilots who drink diet sodas containing aspartame could be more susceptible to conditions ranging from flicker vertigo to gradual loss of vision