Pandemic football was played in front of nobody, which handed researchers an experiment no league would have agreed to run. Dozens of papers followed, each on its own league with its own method, and they do not all say the same thing. A systematic review pulled them together to ask three separate questions: whether shrank, whether suffered, and what the referees did.
Smaller advantage, worse performance, and fairer referees. The review found that the absence of crowds would reduce the home advantage of teams, with findings varying by country. Most leagues showed evidence that without spectator support, technical, tactical and physical performances were worse. And the referee seems likely to be fairer when spectators are absent, which is the part that locates some of the advantage in the officiating.
When football was played without spectators during the pandemic, the crowd was removed from every fixture simultaneously, which is an intervention no competition would otherwise permit. A great many single-league studies followed, using different methods and reaching different conclusions, which is exactly the situation a systematic review exists to resolve.
This one had three stated aims: to analyze whether home advantage was diminished, to investigate the impact of crowd support on match outcome, and to explore without crowds. Keeping them separate matters, because they place the advantage in different hands.
The method followed guidelines, with the literature search conducted in December 2022 using keywords related to soccer, COVID-19 and home advantage. The search returned 135 articles, and after screening against the set criteria, 28 were analyzed.
All three questions got answers. The absence of crowds would reduce the home advantage of teams, though findings varied by country. Most leagues showed evidence that without spectator support, technical, tactical and physical performances were worse. And the referee seems likely to be fairer when spectators are absent. The authors conclude that crowd support is an important factor in home advantage and suggest clubs could strengthen it by encouraging attendance or reducing ticket prices. Note what the pandemic changed besides the crowd: schedules, travel and squad availability all moved at the same time.
wat. Playing to empty stands cut the home advantage, worsened home performance, and appears to have made the referees fairer.
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The three findings do different work. Two locate home advantage in the players, while the third puts part of it in the officials. That is the less comfortable conclusion, and the one a crowd-free season was uniquely able to test.
How do we know?
Wang and colleagues followed PRISMA 2020 guidelines, searching in December 2022 on keywords for soccer, COVID-19 and home advantage, and analyzed 28 of the 135 articles the search returned.
What is still unknown
A review of 28 observational studies whose findings varied by country, so the conclusion is a direction rather than a number. Pandemic football also changed schedules, travel and squad availability alongside the crowds.
Learn something?
Where to next
Do referees call fewer penalties against the home team because of the crowd?officiating
How much of home advantage is the crowd?crowds
Is the crowd really the twelfth player?home advantage