“…Nine clinical trials were reviewed, with one ( Butler, Cullington, Hibbert, Klimes, & Gelder, 1987 ) investigating a similar cognitive-behavioral package rather than Beck and Emery's model per se. Most of the other eight studies ( Barlow et al, 1984 ;Blowers, Cobb, & Mathews, 1987 ;Borkovec & Costello, 1993 ;Borkovec & Mathews, 1988 ;Borkovec, Mathews, Chambers, & Ebrahimi, 1987 ;Butler, Fennell, Robson, & Gelder, 1991 ;Power, Jerrom, Simpson, Mitchell, & Swanson, 1989 ;Power et al, 1990 ) combined cognitive techniques described by Beck and Emery with other behavioral techniques, although the Beck and Emery approach was the primary treatment. Comparisons with control groups (wait list, nondirective therapy, or pill placebo) yielded an average effect size of 1.5.…”