“…This observation was further confirmed in a systematic literature review by Leitner et al (2022) , who identified 26 studies that analyzed the last portion of the 2019–20 season, when all matches were played behind closed doors. Out of these 26 studies, only six did not observe a significant and consistent overall decrease of the home advantage and referee bias in the considered leagues ( Almeida & Werlayne, 2021 ; Benz & Lopez, 2021 ; Krawczyk & Strawinski, 2020 ; Matos et al, 2021 ; Ramchandani & Millar, 2021 ; Wunderlich et al, 2021 ), while the other 20 ones did observe a significant decrease of these phenomena ( Bryson et al, 2021 ; Correia-Oliveira & Andrade-Souza, 2021 ; Cross & Uhrig, 2020 ; Cueva, 2020 ; Dilger & Vischer, 2020 ; Endrich & Gesche, 2020 ; Ferraresi & Gucciardi, 2020 , 2021 ; Fischer & Haucap, 2020 ; Hill & Van Yperen, 2021 ; Jimenez Sanchez & Lavin, 2021 ; Konaka, 2021 ; Leitner & Richlan, 2021a ; Link & Anzer, 2021 ; McCarrick et al, 2021 ; Rovetta & Abate, 2021 ; Santana, Bettega & Dellagrana, 2021 ; Scoppa, 2021 ; Sors et al, 2021 ; Tilp & Thaller, 2020 ). Considering exclusively the peer-reviewed, multi-leagues studies, they found that nine out of 13 studies observed such a decrease ( Bryson et al, 2021 ; Correia-Oliveira & Andrade-Souza, 2021 ; Ferraresi & Gucciardi, 2021 ; Hill & Van Yperen, 2021 ; Jimenez Sanchez & Lavin, 2021 ; Leitner & Richlan, 2021a ; McCarrick et al, 2021 ; Scoppa, 2021 ; Sors et al, 2021 ).…”