Table 1 Reasons for excluding studies

Chambless et al. 1982 [59]

The combination arm used barbiturates, not benzodiazepines.

Chouinard et al. 1982 [60]

Some participants had combination therapy but their outcomes were not reported.

Craske 1991 [61]

The interventions did not involve psychotherapy combined with benzodiazepine.

Echeburua et al. 1993 [62]

Participants were diagnosed as agoraphobia but had no panic attack.

Hafner and Marks 1976 [39]

Participants did not take benzodiazepine on regular basis but on the day of visit only.

Johnston and Gath 1973 [63]

Participants did not take benzodiazepine on regular basis but on the day of flooding only.

Lopez-Alonso and Gomze-Jarabo 2000 [40]

Only the number of completers in both intervention and control groups were described.

Otto et al. 1993 [64]

All participants were prescribed benzodiazepine and this was then tapered.

Riley et al. 1995 [65]

The interventions did not involve the combination of psychotherapy and benzodiazepine.

Spiegel et al. 1994 [66]

All participants were prescribed benzodiazepine and this was then tapered.

Whitehead et al. 1978 [67]

All participants had animal phobia, not panic disorder.