“…Only in two studies, data regarding the sample recruitment process was poorly reported (Seike et al., 2014; Tatangelo et al., 2018). Moreover, seven quantitative studies adopted instruments developed ad hoc (Borson, Scanlan, Sadak, Lessig, & Vitaliano, 2014; De Cola et al., 2017; Hirakawa, Kuzuya, Enoki, & Uemura, 2011; Killen et al, 2016; Koenig, Steiner, & Pierce, 2011; Ryan et al, 2010; Steiner et al., 2016); four studies used tools not formally or totally evaluated for validity and reliability (Black et al., 2013; Ducharme et al., 2014; Tanner et al., 2015); four studies used both validated and non‐validated tools (Gallagher et al., 2011; Hughes et al., 2014; Rosa et al., 2010; Seike et al., 2014) and three used validated tools (Bakker et al, 2014; Muangpaisan et al., 2010; Zauszniewski, Lekhak, Yolpant, & Morris, 2015).…”