It is the Introduction of Accuracy and Precision

1. Accuracy and Precision
Mrs. Poonam Sunil Aher (M.Pharm, PhD)
Assistant Professor
Sanjivani College of Pharmaceutical Education and Research
(Autonomous),
Kopargaon, Ahmednagar-423603 (M.S.), INDIA
Mobile: +91-9689942854

2. • Accuracy:
• Accuracy is a measure of the closeness of the experimental
value to the actual amount of the substance in the matrix.
• The accuracy of an analytical procedure expresses the
closeness of agreement between the value which is accepted
either as a conventional true value or an accepted reference
value and the value found. This is sometimes termed
trueness.
• The purpose of analysis of botanicals and other natural
products is quantitation of target compounds in the matrix in
which the compounds occur. The most common technique for
determining accuracy in natural product studies is the spike
recovery method, in which the amount of a target compound
is determined as a percentage of the theoretical amount
present in the matrix

3. • Precision:
• The precision of an analytical procedure expresses the
closeness of agreement (degree of scatter) between a
series of measurements obtained from multiple sampling
of the same homogeneous sample under the prescribed
conditions.
• Precision may be considered at three levels:
• Repeatability, intermediate precision and reproducibility.
Precision should be investigated using homogeneous,
authentic samples.
• The precision of an analytical procedure is usually
expressed as the variance, standard deviation or
coefficient of variation of a series of measurements.

4. • Repeatability
• Repeatability expresses the precision under the same operating
conditions over a short interval of time. Repeatability is also termed
intra-assay precision.
• Intermediate precision
• Intermediate precision expresses within-laboratories variations:
different days, different analysts, different equipment, etc.
• Reproducibility
• Reproducibility expresses the precision between laboratories
(collaborative studies, usually applied to standardization of
methodology).

5. Accuracy is measure of the closeness of the
experimental value to the actual or true
value
The precision of an analytical procedure
expresses the closeness of agreement
between series of measurement
Here goal should be accurate Here goal should be Precise
Accuracy requires closeness level in 80,100,120% or
50,100,150% levels
Precision requires repetability