Dear Jesper, Thank you for your detailed statement. It was my original fear that I commited a common mistake in the input for the statistical evaluation. Christine ------------------------------------------------------------------------------- Christine Preibisch Klinikum der Universitaet Frankfurt ZRAD - Institut fuer Neuroradiologie Schleusenweg 2-16 60528 Frankfurt Germany Phone: ++49 69 6301 4651 Fax: ++49 69 6301 5989 email: [log in to unmask] ------------------------------------------------------------------------------- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%