Management of Helicobacter pylori infection in Latin America: A Delphi technique-based consensus

Table 1 Levels of evidence according to the study design[3]

Level of evidence	Description
Type I	Evidence obtained at least from one well-designed, randomized, controlled1 trial or from a systematic review of randomized clinical studies
Type II	II-1 Evidence obtained from non-randomized, prospective, controlled1 studies
	II-2 Evidence obtained from cohort observational studies2 or case-control studies, preferably multi-centric
	II-3 Evidence obtained from case series
Type III	Opinion of authorities on the subject matter based on expertise, expert committees, case reports, pathophysiological studies or basic science studies

¹A controlled study is a study where the intervention is managed by the researcher;

²An observational study is a study where the intervention is not controlled by the researcher.

Table 2 Levels of recommendation according to the available evidence[3]

Recommendation	Description
A	The Consensus strongly recommends the mentioned intervention or service. This recommendation is based on high quality evidence, with a benefit that significantly exceeds the risks
B	The Consensus recommends the regular clinical use of the mentioned intervention or service. This recommendation is based on moderate quality evidence, with a benefit that exceeds the risks
C	The Consensus does not make any positive or negative recommendation regarding the mentioned intervention or service. A categorical recommendation is not provided, because the evidence (of at least moderate quality) does not show a satisfactory risk/benefit relationship. The decision has to be made on a case-by-case basis
D	The Consensus makes a negative recommendation against the mentioned intervention or service. The recommendation is based on at least moderate quality evidence, not showing any benefit or where the risk or damage exceeds the benefits of the intervention
I	The Consensus concludes that the evidence is insufficient, due to low-quality studies, heterogeneous results or because the risk/benefit balance cannot be determined