Table 2 Criteria for assessing bias in the systematic review of studies evaluating the diagnostic accuracy of MAT, PCR, and IgM ELISA, published global and between 1950–2022
Domain | Grade | Criteria |
|---|---|---|
A. Criteria for assessing bias in studies selected for MAT accuracy evaluation | ||
 Patient selection | Low risk | Prospective studies and case-control studies in the same population |
High risk | Case-control studies in different populations or healthy controls; eligibility other than suspected leptospirosis | |
 Index test (MAT) | Low risk | MAT performed in paired samples with a positivity criteria of ≥ 4-fold rise or seroconversion |
High risk | MAT performed in single acute-phase samples; any other positivity criteria for paired samples different than ≥ 4-fold rise or seroconversion | |
 Comparator test (culture and/or PCR) | Low risk | Performed in recruitment samples; performed according to standard methodology |
High risk | Performed in convalescent samples; not performed according to standard methodology | |
 Flow and timing | Low risk | All patients subject to the same comparator tests; comparator tests and index test performed on samples taken at the same time for acute phase |
High risk | Not all participants performed the same comparator test; use of samples collected on different days for acute phase | |
B. Criteria for assessing bias in studies selected for PCR accuracy evaluation | ||
 Patient selection | Low risk | Prospective studies and case-control studies in the same population |
High risk | Case-control studies in different populations or healthy controls; eligibility other than suspected leptospirosis | |
 Index test (PCR) | Low risk | Performed in recruitment samples; performed according to standard methodology |
High risk | Performed in convalescent samples; not performed according to standard methodology | |
 Comparator test (MAT and/or culture and/or PCR) | Low risk | Use of MAT on paired samples in at least 75% of participants; cases defined with ≥ 4-fold rise in antibody titers or with a positive culture of Leptospira; tests performed according to standard methodology |
High risk | Use MAT on less than 75% of paired samples, any other positivity criteria for paired samples different than ≥ 4-fold rise or seroconversion; tests not performed according to described methodology | |
 Flow and timing | Low risk | All patients subject to the same comparator tests; comparator tests and index tests performed on samples collected at the same time for acute phase |
High risk | Not all participants performed the same comparator test; use of samples collected on different days for acute phase | |
C. Criteria for assessing bias in studies selected for IgM ELISA accuracy evaluation | ||
 Patient selection | Low risk | Prospective studies and case-control studies in the same population |
High risk | Case-control studies in different populations or healthy controls; eligibility other than suspected leptospirosis | |
 Index test (IgM ELISA) | Low risk | Threshold for positivity defined a priori; test performed according to manufacturer’s recommendations |
High risk | Threshold for positivity not defined a priori; test not performed according to manufacturer’s recommendations | |
 Comparator test (MAT, culture and/or PCR) | Low risk | Use of MAT on paired samples in at least 75% of participants, cases defined as a positive PCR, MAT with ≥ 4-fold rise in antibody titers or a positive culture of Leptospira; tests performed according to described methodology |
High risk | Use MAT on less than 75% of paired samples; culture and PCR performed in convalescent samples, any other positivity criteria for MAT than ≥ 4-fold rise or seroconversion between paired samples; tests not performed according to standard methodology | |
 Flow and timing | Low risk | All patients subject to the same comparator tests; comparator tests and index test performed on samples collected at the same time for acute phase |
High risk | Not all participants performed the same comparator test; use of samples collected on different days for acute phase | |