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Fig. 2 | BMC Research Notes

Fig. 2

From: Validation of an automated colony counting system for group A Streptococcus

Fig. 2

Comparison between freshly prepared THY-TTC plates and plates stored at 4 °C for 4 weeks. The analysis compares each replicate of each dilution with the sample from the same culture plated on the 4 week old plates and the fresh plates. The Y axis is based on the formula [100 × (4 week old plates–fresh plates)/average of the two points] and the X axis is the average of the two points. The bias of 5.01 indicates that plates maintain their utility for this period. The dotted-lines represent the 95 % limits of agreement and range from −51.79 to 61.80. For the comparison between the plates, a series of three dilutions were plated for four strains in duplicate, of which 17 counts fell between 10 and 200 colonies. Each point represents one dilution point of each replicate

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