Bioequivalence and Bioavailability Forum • Calculation of ISR deviation

Calculation of ISR deviation [Bioanalytics]

posted by Helmut – Vienna, Austria, 2013-04-23 21:30 (4417 d 00:36 ago) – Posting: # 10477
Views: 9,197

Dear all,

stupid question. Sometimes I feel I’m lacking the most basic skills. EMA’s GL states:

The concentration obtained for the initial analysis and the concentration obtained by reanalysis should be within 20% of their mean for at least 67% of the repeats.

In the past we have calculated the percent deviation of the difference between measurements from their mean. Example:

  1st     2nd     x      ∆_2-1    |∆ (% x)|

40.303  42.333  41.318  +2.030     4.91

Have we been too stringent? Does EMA expect instead:

  1st     2nd     x      ∆_1-x    ∆_2-x    ∆₁ (% x)  ∆₂ (% x)  |∆_1,2 (% x)|

40.303  42.333  41.318  -1.015  +1.015   -2.46     +2.46        2.46

Confusing.

—
Dif-tor heh smusma 🖖🏼 Довге життя Україна!
Helmut Schütz

The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes

Complete thread:

Calculation of ISR deviationHelmut 2013-04-23 19:30
- Calculation of ISR deviation ElMaestro 2013-04-23 20:30
  - I see… Helmut 2013-04-23 22:08
  - Calculation of ISR deviation Roberto 2013-12-09 12:52
- Calculation of ISR deviation Ohlbe 2013-04-24 09:40
  - Calculation of ISR deviation Helmut 2013-04-24 14:07
    - Calculation of ISR deviation Ohlbe 2013-04-24 22:37
      - Calculation of ISR deviation Helmut 2013-04-25 02:00