The statistical analyses were performed using the SAS-program (SAS Inst. Inc., Cary, NC).
Data were handled and analyzed using the SAS-program (ver. 9.2, SAS Inst. Inc., Cary, NC, USA).
Statistical analysis was performed using the SAS statistical program (SAS-PC, version 9.3; SAS Institute Inc., Cary, NC).
All analyses were performed using the SAS statistical program (SAS-PC, Version 8.0; SAS Institute Inc., Cary, NC, USA).
All statistical analyses were performed using the SAS statistical program (SAS-PC, version 9.1; SAS Institute Inc., Cary, NC, USA).
Data were analyzed using the SAS statistical program (ver. 9.2 [SAS Institute]); details of the analytical methods were as follows.
The significant difference compared to the control group was statistically analyzed by Student's t-test using the SAS software program (SAS/STATA version 8.2; SAS Institute, Cary, NC, USA).
Multilevel regression models were estimated by the PROC GLIMMIX - "Generalized Linear Models-Mixed" procedure using the SAS 9.2, statistical software program (SAS/STAT Guide for personal computers. Cary: North-Carolina/USA; 2001).
This was achieved using the SAS software package (SAS Institute Inc., Cary, NC, USA) and code developed by JM specifically for this task, similar to the program Lexis.sas by Carstensen (2007).
The primary analysis (sequential test) was performed using the SAS software (SAS® software, version 9.2, for Windows (SAS Institute, Cary, NC, USA)).
