Table 2.
Main results for AAI compared with standard PTSD psychotherapy or waitlist at baseline and at the end of treatment
| Treatment effects Comparison & outcome | Number of comparisons | Group difference SMD (95% CI) |
P-value for group difference | Heterogeneity (I2) | Tau2 | P-value for heterogeneity |
|---|---|---|---|---|---|---|
| AAI vs. standard PTSD psychotherapy: PTSD symptom severity | ||||||
| Baseline | 3 | −0.16 (−0.60 to 0.28) | 0.479 | 50.6% | 0.1 | 0.132 |
| End of treatment | 3 | −0.26 (−0.56 to 0.04) | 0.087 | 00.0% | 0.0 | 0.865 |
| AAI vs. waitlist: PTSD symptom severity | ||||||
| Baseline | 1 | −0.04 (−0.68 to 0.60) | 0.900 | NA | NA | NA |
| End of treatment | 1 | −0.82 (−1.56 to −0.98) | 0.029 | NA | NA | NA |
| AAI vs. standard PTSD psychotherapy: depression | ||||||
| Baseline | 2 | −0.48 (−1.16 to 0.19) | 0.162 | 00.0% | 0.0 | 0.875 |
| End of treatment | 2 | −0.14 (−0.82 to 0.54) | 0.687 | 00.0% | 0.0 | 0.677 |
| Sensitivity analysis Baseline | 1 | −0.53 (−1.40 to 0.35) | 0.238 | NA | NA | NA |
| Sensitivity analysis end of treatment | 1 | −0.03 (−0.88 to 0.83) | 0.951 | NA | NA | NA |
| Getting service dog vs. waiting for service dog: PTSD symptom severity | ||||||
| Baseline | 2 | −0.08 (−0.38 to 0.21) | 0.572 | 00.0% | 0.0 | 0.934 |
| End of treatment | 2 | −0.58 (−0.88 to −0.28) | < 0.001 | 00.0% | 0.0 | 0.390 |
|
Drop-outs Comparison |
||||||
| AAI vs. standard PTSD psychotherapy | 5 | 1.99 (0.46 to 8.55) | 0.1354 | 22.8% | 0.67 | 0.269 |
| AAI vs. waitlist | 1 | 10.8 (1.16 to 100.43) | 0.036 | NA | NA | NA |
| Getting service dog vs. waiting for service dog | 2 | 3.14 (0.35 to 28.46) | 0.310 | 00.0% | 0.0 | 0.904 |
AAI: animal-assisted intervention; N: number of included studies; SMD: standard mean difference, OR: odds ratio.