Table 2

Long-term effects of CBT compared with pharmacotherapy: ORs of response†

NOR95% CII2‡95% CINNT95% CI
CBT vs continued pharmacotherapy
 All studies51.620.97 to 2.72 *00 to 7910
 One possible outlier excluded††41.771.04 to 3.0100 to 8584 to 71
CBT vs discontinued pharmacotherapy
 All studies82.611.58 to 4.31****00 to 6854 to 11
 Three possible outliers excluded‡‡52.471.45 to 4.22****00 to 7964 to 15
Subgroups (long-term effects)
  SSRI23.021.29 to 7.04**0¶¶50.82
  TCA52.661.40 to 5.04***00 to 7964 to 15
 Included sample
  All21.970.91 to 4.27 *0¶¶90.14
  Responders63.201.65 to 6.19***00 to 7543 to 8
  All 4 criteria52.311.28 to 4.16***00 to 7962 to 110.25
  ≤3 criteria33.581.39 to 9.22***00 to 9042 to 10
 Short-term effects
 All the studies91.150.74 to 1.79530 to 7820
 One possible outlier excluded†††80.960.72 to 1.3000 to 68
 Drop out from intervention‡‡‡80.590.34 to 0.99**480 to 7795 to 143
  • *p<0.1.

  • **p<0.05.

  • ***p<0.01.

  • ****p<0.001.

  • †According to the random effects model.

  • ‡In this column, I2 is reported; we also tested whether the Q value was significant. This was the case in two comparisons (indicated with an asterisk*).

  • §The p value indicates whether the subgroups differ from each other.

  • ¶The 95% CI includes zero and would result in a negative NNT; therefore, we do not report the 95% of the NNT here the 95% CI included zero; because this would result in a negative NNT, we do not report this here.

  • ††Jarrett et al26.

  • ‡‡Blackburn et al, 1981; Jarrett et al26; Evans et al24.

  • §§One study examined phenelzine (Jarrett et al26); this was not included in the analyses.

  • ¶¶95% CI could not be calculated when degrees of freedom is lower than two.

  • †††Kovacs et al27.

  • ‡‡‡One study did not report data on drop out (Blackburn et al 21).

  • CBT, cognitive behaviour therapy; NNT, numbers-needed-to-be-treated; SSRI, selective serotonin reuptake inhibitor; TCA, tricyclic antidepressant.