Table 2.

Evidence type used in appraising the quality of the evidence of included papers.

Level Type	Description
Level I	Experimental, randomized controlled trial (RCT), systematic review RTCs with or without meta-analysis
Level II	Quasi-experimental studies, systematic review of a combination of RCTs and quasi-experimental studies, or quasi-experimental studies only, with or without meta-analysis
Level III	Nonexperimental, systematic review of RCTs, quasi-experimental with/without meta-analysis, qualitative, qualitative systematic review with/without meta-synthesis
Level IV	Respected authorities’ opinions, nationally recognized expert committee or consensus panel reports based on scientific evidence
Level V	Literature reviews, quality improvement, program evaluation, financial evaluation, case reports, nationally recognized expert(s) opinion based on experiential evidence