The Chicago Bears' defense leads the league in 20 of 38 statistics used in the computerized scouting report. Obviously, if Chicago wins the Super Bowl, it will be more a result of its defense than Jim McMahon's passing or Walter Payton's running.

One of the few defensive statistic in which the Bears do not lead the league is fewest first downs allowed rushing. The Raiders led the league with 73 for the season but the Bears were close behind with 74.

Statistical questions to ask as the game progresses: The Bears led the NFL with an average of 40 rushes per game in 1984 and 1985 combined. Teams this year with 40 or more rushes won 68, lost two. Can the Bears rush 40 times against the Patriots' defense (allowing 3.55 yards per rush)? Can the Patriots run 40 times against the Chicago defense?

The pass completion percentage (sacks counted as attempts) has emerged this year as a key stat. The league average is less that three sacks per game. Can either McMahon or the Patriots' Tony Eason complete 55 percent of their passes, counting sacks?

McMahon has a modest 49.9 percent completion rate (ranking 12th). The Patriots have been allowing a 45 percent completion rate and a computer analysis says this statistic will be the key with the Bears' offense facing the Patriots' defense.

On the ratio of passing touchdowns to interceptions, the Bears have a mark of .5 (one passing touchdown for each two interceptions stolen). Teams throwing two or more interceptions this year lost 80 percent of the time.

The Patriots' pass defense was the most improved in the NFL this season in terms of percent of passing touchdowns allowed. Statistically, they should challenge McMahon.

The Patriots' defense has allowed only 3.5 yards per carry, ranking fourth. So Payton should be challenged, too, along with the rest of the Bears' rushers.

The Bears led the NFL this season with an average of 38 carries per game (and led in 1984 with 42); their defense allowed a league-low 22 carries per game.

The Bears' defense has a significant advantage on paper. Nevertheless, statistics don't win games. People do. Using season averages, the computer projection is the Bears by 11.