BQL or LOQ - Can I translate it as = 0 (ZERO)?

Hello !!
I have to transcribe an analytical data received from a supplier .
Its result is: BQL .
Can I translate it as = 0 (ZERO) ?

Because my software does’t accept letters but only digits
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Get ‘new’ software! BQL is usually reported as <LOQ rather than giving a number which may vary (machine, analyst, time of day…)

I think you have to put it in as your BQL value. The FDA (or other agency) would appreciate that you assume the value is worst case, and not best case (which would be zero). Really it won’t affect your results or conclusions any, it would help the FDA (other agency) trust that you are aware of limitations of your equipmet/method, and again assume the worst case scenario and err on the side of caution.

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unfortunately I do not know the value of BQL. The supplier is not able to tell me.

Then you will have to determine it yourself from the linearity curve.

The Detection Limit and Quantitation Limit can also be calculated from the slope and standard deviation (SD) of the linearity curve.

Detection Limit,	DL = SD x 3/slope

Quantitation Limit,	QL = SD x 10/slope

SD = [(y-y’)2/ (n-2)]1/2
Slope = slope of the linearity curve obtained by regression analysis
n = number of points
y = experimental response
y’= calculated response found using the x-value (concentration) and the regression equation
(y-y’) = difference or residual between experimental and calculated response for each x-value