Bioequivalence and Bioavailability Forum

Dear Raja,

which version of WinNonlin are you using? Current are WinNonlin 5.3 and Phoenix 6.1…

• Read the software’s documentation.
  
• See this thread.
  
• Register to Pharsight’s Extranet and ask your question there.

PHX & WNL have tools to deal with BQL-values. Essentially you generate a new column of data based on your SOPs or conditions stated in the statistical analysis plan and/or clinical protocol. Nothing to be done by trial-and-error! Common rule sets treat BQLs between time of administration and t_max as zero and values after t_max as e.g. LLOQ/2 (I would not recommend that) or as a nonnumeric value. ‘BQL’ itself is an acceptable nonnumeric value in PHX, whereas WNL only accepts ‘Missing’ – which is not so nice, because the value is not missing… Nonnumerics are ignored in summary statistics (e.g., in construction mean-profiles). Now it’s again up to you to apply a rule up to which percentage you will accept values. Many people use a minimum of ~67–75%.
If you have BQL-values embedded within values >LLOQ (see Simon’s example above), I would recommend to use the lin-up/log-down trapezoidal rule in order to avoid an AUC biased by linear inter­polation. Again: no cherry-picking; must be stated in the SAP / protocol.