Contribution to the Detection of Poor Quality Sildenafil Drugs in Burkina Faso Using High-Performance Thin-Layer Chromatography

Table 4

Mode of calculation of the criteria of fidelity and trueness by level.

Criteria	Calculation methods	Levels
		1	…	k
Intermediate fidelity standard deviation
Intermediate fidelity variation coefficient
Absolute mean bias
Relative average bias	× 100
Average recovery rate

: mean concentration found; : mean reference value; : repeatability standard deviation; : interseries standard deviation.