Bioequivalence and Bioavailability Forum • Reason for failing to calculate lambda and Kel in Phoenix

Reason for failing to calculate lambda and Kel in Phoenix [Software]

posted by jag009 – NJ, 2026-01-29 05:20 (140 d 12:31 ago) – Posting: # 24559
Views: 2,868

Hi Helmut and others,

Revisiting this thread.... Does Phoenix provide a reason somewhere in the result/output as to why kel cannot be estimated for a subject? I know the Use guide lists the reasons but I am looking for something in the result output relevant to the subject's profile.

I use the best fit method for slope calculation. The semi-log plot just showed the statement "cannot be determined" or something, the "warning and error" output showed "No parameters could be extrapolated to infinity". I didnt see anything in the core output.

thx
J

Complete thread:

new regression rule for lambda_z in Phoenix: bug or new feature? Shuanghe 2025-11-10 15:55
- new regression rule for lambda_z in Phoenix: bug or new feature? Helmut 2025-11-11 08:42
- new regression rule for lambda_z in Phoenix: no change in implementation SDavis 2025-11-11 14:24
  - new regression rule for lambda_z in Phoenix: no change in implementation Shuanghe 2025-11-11 22:38
    - Old User’s Guides Helmut 2025-11-11 23:20
    - Misinterpretation Helmut 2025-11-12 12:16
      - Misinterpretation Shuanghe 2025-11-12 21:24
        
        Misinterpretation Helmut 2025-11-15 09:38
        Misinterpretation billdenney 2026-02-27 14:20
        
        Clarification Helmut 2026-02-27 15:29
  - Rewording appreciated Helmut 2025-11-12 10:30
    - Reason for failing to calculate lambda and Kel in Phoenixjag009 2026-01-29 04:20
      - Reason for failing to estimate λz Helmut 2026-01-29 11:04