Table 1 Interference criteria interpretation grid for co-infection interference studies

% of positive calls

% of positive calls

ΔCt

<  85%

Any %

Any ΔCt

The experiment is invalid. The causes of the shift in sensitivity must be investigated and the experiment reconducted.

≥ 85%

<  85%

Any ΔCt

The highly-concentrated DNA or the tested substance is considered to be interfering with the detection of the target pathogen if any of these 2 criteria are met.

Any %

ΔCt ≥ 2SDrep

≥ 85%

≥ 85%

Any ΔCt

The highly-concentrated DNA or the tested substance is considered not to be interfering with the detection of the target pathogen if both criteria are met.

Any %

ΔCt < 2SDrep