Table 5.

Summary of key evidence to support response scale selection for children 10 to 18 years old

Reference, Evidence Typea, and Gradeb	Article Type/ Population	Response Option Type	Conclusions
Lakkis et al. 2006 [19], Direct, C	Intervention Study; Children aged 10 to 15 years old	VRS	There were no difficulties with the completion of the questionnaires, suggesting that 5-point VRS can be administered effectively to children and adolescents aged 10 to 15 years. Study participants were able to discriminate between and respond to questions easily using the 5-point scale.
Takahashi & Yamamoto. 2006 [18], Direct, A	Prospective Study; Children aged 11 to 18 years old	Faces scales; NRS; VAS	In children 11 to 18 years, NRS produced higher scores than Faces or VAS but NRS and VAS had higher correspondence than with Faces.
Bennett et al. 2010 [20], Direct, C	Instrument Development and/or Validation study; Children aged 12 years and older	VRS	Two methods for measuring the 7-day symptom experience of patients 12 years and older with cystic fibrosis, in which the two methods (a single 7-day recall and repeated 24-h recall) were found to provide similar results for groups of patients using a 5-point VRS.

^aDirect evidence: Primary research that compares different response scales within study. Indirect evidence: Review or expert opinion based on empirical evidence

^bGrade Key: A) Primary research; compares different response scales within the study; B) Review or expert opinion; based on an empirical evidence base; C) Primary research; evaluates a single response scale type within the study; and D) Review or expert opinion, based on expert consensus, convention or historical experience