According to WikipediA, in baseball a quality start is a statistic for a starting pitcher defined as a game in which the pitcher completes at least six innings and permits no more than three earned runs. The quality start has effectively replaced the ‘complete game’ as a meaningful measure of a starting pitcher’s performance.
The quality start was developed by sportswriter John Lowe in 1985 while writing for The Philadelphia Inquirer. Nolan Ryan has used the term “High Quality Start” for games where the pitcher goes seven innings or more and allows three earned runs or fewer, which baseball columnist and formber BBWAA president Derrick Goold referred to as “Quality Start Plus.”