Table 2.
Intent-to-Treat Sample: A Comparison of Explained Variances (R2) for Mean PTSD Symptom Cluster and Total Scores With a Linear Versus Quadratic Fit for Prolonged Exposure (PE) and Cognitive-Processing Therapy (CPT)
| Treatment | R2 (%) | df | F | Sig F | b0 (Sig t) | b1 (Sig t) | b2 (Sig t) |
|---|---|---|---|---|---|---|---|
| PE: Reexperiencing | |||||||
| Linear | 62 | 3 | 4.85 | .11 | 8.21 (0.01) | −0.76 (0.11) | |
| Quadratic | 96 | 2 | 27.57 | .03 | 4.85 (0.03) | 2.12 (0.08) | −0.48 (0.05) |
| CPT: Reexperiencing | |||||||
| Linear | 63 | 3 | 5.19 | .11 | 8.48 (0.01) | −0.90 (0.11) | |
| Quadratic | 96 | 2 | 25.54 | .04 | 4.62 (0.05) | 2.40 (0.10) | −0.55 (0.05) |
| PE: Avoidance | |||||||
| Linear | 88 | 3 | 22.31 | .02 | 15.01 (0.01) | −1.62 (0.02) | |
| Quadratic | 99 | 2 | 185.74 | .01 | 11.58 (0.01) | 1.32 (0.10) | −0.49 (0.02) |
| CPT: Avoidance | |||||||
| Linear | 94 | 3 | 43.95 | .01 | 15.03 (0.01) | −1.75 (0.01) | |
| Quadratic | 99 | 2 | 99.99 | .01 | 12.55 (0.01) | 0.38 (0.62) | −0.35 (0.08) |
| PE: Arousal | |||||||
| Linear | 85 | 3 | 16.43 | .03 | 11.81 (0.01) | −1.13 (0.03) | |
| Quadratic | 98 | 2 | 59.49 | .02 | 9.12 (0.01) | 1.18 (0.18) | −0.38 (0.05) |
| CPT: Arousal | |||||||
| Linear | 90 | 3 | 26.31 | .01 | 11.95 (0.01) | −1.23 (0.01) | |
| Quadratic | 100 | 2 | 549.54 | .01 | 9.50 (0.01) | 0.86 (0.05) | −0.35 (0.01) |
| PE: Total PSS | |||||||
| Linear | 82 | 3 | 13.54 | .03 | 35.01 (0.01) | −3.50 (0.03) | |
| Quadratic | 99 | 2 | 97.10 | .01 | 25.54 (0.01) | 4.61 (0.08) | −1.35 (0.03) |
| CPT: Total PSS | |||||||
| Linear | 87 | 3 | 20.34 | .02 | 35.46 (0.01) | −3.91 (0.02) | |
| Quadratic | 99 | 2 | 101.91 | .01 | 26.92 (0.01) | 3.41 (0.15) | −1.22 (0.04) |
Note. PTSD = posttraumatic stress disorder; Sig = significant; PSS = PTSD Symptom Scale.