“…Positive effects on singing ability have been found for feedback (Porter, 1977;Welch, Howard, & Rush, 1989), literature dissemination (Apfelstadt, 1984;Klinger et al, 1998), the presence and type of singing instruction (Apfelstadt, 1984;Miyamoto, 2005;Rutkowski, 1996), and pattern instruction (Jarjisian, 1983;Porter, 1977). Use of intervals and content familiarity has been found to have positive effects on singing ability (Fyk, 1985;Moore, 1994;Reifinger, 2009Reifinger, , 2012. Conflicting effects, however, on singing ability have been found for vocal model (Green, 1990;Small & McCachern, 1983;Yarbrough, Green, Benson, & Bowers, 1991;Yarbrough, Bowers, & Benson, 1992), use of singing voice (Persellin, 2006;Phillips, 2014), use of accompaniment (Atterbury & Silcox, 1993;Guibault, 2004), effect of repetitive practice (Paney & Kay, 2014;Reifinger, 2009;Small & McCachern, 1983;Welch et al, 1989), population (Moore et al, 1995(Moore et al, /1996Moore et al, 2004), performance context (Goetze & Horii, 1989;Moore et al, 2004;Yarbrough et al, 1991), and text Gault, 2002;Guerrini, 2006;Rutkowski, 1990).…”