“…The NF was assessed by two studies as part of the PTSD symptomatology (Currie, 2021 ; Jiang et al, 2020 ) and as an independent index of psychological distress in adults, adolescences, and children in three studies (Ferraro et al, 2021 ; Musse et al, 2020 ; Reséndiz‐Aparicio, 2021 ). In a further 12 studies it was considered as an index of sleep impairment and poor sleep quality (Dondi et al, 2021 ; Goncalves et al, 2022 ; Goweda et al, 2020 ; Lin, Lin, et al, 2021 ; Parrello et al, 2021 ; Partinen et al, 2021 ; Pérez‐Carbonell et al, 2020 ; Petrov et al, 2021 ; Ramos Socarras et al, 2021 ; Scarpelli, Gorgoni, et al, 2022 ; Scarpelli, Nadorff, et al, 2022 ; Scarpelli, Alfonsi, et al, 2022 ; Schlarb et al, 2020 ), whereas in seven studies it was considered as a dreaming life phenomenon (Guerrero‐Gomez et al, 2021 ; Holzinger et al, 2021 ; Kennedy et al, 2021 ; Kilius et al, 2021 ; Pesonen et al, 2020 ; Scarpelli, Alfonsi, Gorgoni, et al, 2021 ; Scarpelli, Alfonsi, Mangiaruga, et al, 2021 ); five studies overlap nightmares with bad or threatening dreams, focusing attention on the content component (Guo & Shen, 2021 ; Iqbal et al, 2021 ; Korukcu et al, 2022 ; Solomonova et al, 2021 ; Yasmin et al, 2021 ); one study considered nightmares as a symptom of COVID‐19‐related stress (Taylor et al, 2020 ).…”