RT Journal A1 Klerman GL, Ballenger JC, Burrows GD, et al T1 The 'efficacy' of alprazolam in panic disorder and agoraphobia: A critique of recent reports-reply JF Archives of General Psychiatry JO Archives of General Psychiatry YR 1989 FD July 1 VO 46 IS 7 SP 670 OP 672 DO 10.1001/archpsyc.1989.01810070096016 UL http://dx.doi.org/10.1001/archpsyc.1989.01810070096016 AB In Reply.—  Professor Marks and a number of distinguished psychiatrists and psychologists from several countries have written to criticize the set of our articles reporting on the first phase of the Cross-National Collaborative Panic Study, which appeared in the May 1988 issue of the Archives. Their letter raises a number of questions specific to the study's findings and comments on larger issues in the treatment of panic disorder and agoraphobia.Establishing the Short-term Efficacy of Alprazolam for Panic Disorder and Agoraphobia.—  The main criticism of Professor Marks and associates' is that "this claim of 'efficacy' is misleading given the arguable interpretation of the data presented." To respond to this criticism, it is important to specify the criteria of efficacy being employed. Nowhere in the letter from Professor Marks et al do they state explicitly their criteria for efficacy.In the Cross-National Collaborative Panic Study, First Phase, the criteria of