Table 1.

Interpretive criteria and laboratory testing method used among 198 included studies of antimicrobial resistance of Salmonella Typhi, global, 1972 through 2018

Interpretive criteria	Number of studies (% of 198 included*)
CLSI	83 (41.9)
Pre-2012	35 (17.7)
2012 or later	38 (19.2)
Specific year unreferenced†	10 (5.1)
Not reported	59 (29.8)
The National Committee for Clinical Laboratory Standards (now CLSI as of 2005)	47 (23.7)
The European Committee on Antimicrobial Susceptibility Testing	10 (5.1)
The British Society for Antimicrobial Chemotherapy	7 (3.5)
The French Microbiology Society	2 (1.0)
Laboratory antimicrobial susceptibility testing method
Disc diffusion‡	173 (87.4)
Minimum inhibitory concentration§	82 (41.4)
Combination of at least two methods	78 (39.4)
Automated	12 (6.1)
Not reported	9 (4.5)

CLSI = Clinical and Laboratory Standards Institute.

^*Some studies used multiple interpretive criteria or testing strategies for different antimicrobials; thus, numbers will exceed the total number of studies included.

^†Two studies specified multiple CLSI years covering both pre-2012 and 2012 or later.

^‡The Kirby–Bauer test and the Stokes method.

^§E-test, agar dilution, and broth dilution.