Figure 1From: Determination of PCR efficiency in chelex-100 purified clinical samples and comparison of real-time quantitative PCR and conventional PCR for detection of Chlamydia pneumoniaeDetermination of the efficiency for the standard, reference and clinical samples. The threshold cycle is the cycle number at which the fluorescence curve for a given sample crosses the user-defined noise band. Log to the concentration for the reference samples is set as log to arbitrary numbers with four-fold difference as the reference samples are four-fold serial dilutions. The actual concentration is not needed when determining the efficiency as it depends on the slope of the line only.Back to article page