Systematic review protocol examining the effectiveness of hospital clowns for symptom cluster management in paediatrics - Lopes Júnior, Luís Carlos; Lima, Regina Aparecida Garcia de; Olson, Karin; Bomfim, Emiliana de Omena; Neves, Eliane Tatsch; Silveira, Denise Sayuri Calheiros da; Nunes, Michelle Darezzo Rodrigues; Nascimento, Lucila Castanheira; Bisson, Gabriela Silva (BMJ Open, 2019)