Table 3.
Group means (standard deviations) and statistical contrasts for outcome measures in high drug compliance subjects
| Placebo n = 12 | Propranolol n = 8 | df, t, P | Difference in Means | 95% Confidence Interval | |
|---|---|---|---|---|---|
| One‐month posttrauma assessment | |||||
| Physiological PTSD probability (%) | 44.6 (17.5) | 32.6 (5.9) | 18, 2.2, <0.05a | 12.0 | 0.3 to 23.6 |
| Heart rate response (BPM) | 3.1 (3.6) | −1.5 (3.2) | 18, 3.0, 0.009 | 4.6 | 1.3 to 7.9 |
| Skin conductance response (μS) | 0.68 (1.22) | 0.17 (0.30) | 18, 1.4, 0.19a | 0.51 | −0.28 to 1.31 |
| Frontalis EMG response (μV) | 0.9 (1.6) | 0.6 (1.2) | 18, 0.4, 0.68 | 0.3 | −1.1 to 1.6 |
| Clinician Admin PTSD Scale | 33.3 (30.3) | 22.1 (21.3) | 18, 0.9 0.38 | 11.2 | −14.8 to 37.3 |
| PTSD diagnosis (Y/N) | 4/8 | 1/7 | 0.60b | ||
| Three‐month posttrauma assessment | |||||
| Physiological PTSD probability(%) | 35.8 (15.3) | 31.0 (3.9) | 17, 1.0, 0.34a | 4.8 | −5.7 to 15.4 |
| Heart rate response (BPM) | 1.9 (4.1) | −0.2 (2.3) | 17, 1.3, 0.22 | 2.1 | −1.4 to 5.4 |
| Skin conductance response (μS) | 0.22 (0.95) | −0.01 (0.34) | 15, 0.7, 0.50a | 0.23 | −0.48 to 0.93 |
| Frontalis EMG response (μV) | 0.0 (0.5) | 0.2 (0.3) | 17, −1.0, 0.35 | −0.2 | −0.6 to 0.2 |
| Clinician Admin PTSD Scale | 25.3 (28.4) | 18.5 (31.1) | 18, 0.5, 0.62 | 6.8 | −21.5 to 35.0 |
| PTSD diagnosis (Y/N) | 3/9 | 1/7 | 0.62b | ||
n, sample size; df, degrees of freedom (where lower than expected according to sample sizes, this is due to missing data); t, Student's t; P, statistical probability level; PTSD, posttraumatic stress disorder; Physiological PTSD probability, percent posterior probability of classification in PTSD reference group, which is an a priori measure of overall physiological responding during script‐driven traumatic imagery (see text for explanation); BPM, beats per minute; μS, microSiemens; μV, microVolts.
aSatterthwaite t‐test for unequal variances.
bFisher's exact test.