Table 3.
ITT analysis results for secondary outcomes (treatment effects for between-arm comparisons).
| Measure | Delayed arm | Immediate arm | ITT treatment effect estimate (between-arms) | |||||
|---|---|---|---|---|---|---|---|---|
| N | Mean | SD | N | Mean | SD | Mean Difference | 95% CI | |
| Clinical Symptoms | ||||||||
| PTSD (PCL-5 4-item) | ||||||||
| Baseline | 43 | 8.00 | 3.27 | 42 | 8.71 | 3.64 | ||
| Week 4 | 38 | 6.74 | 2.62 | 31 | 4.26 | 2.86 | −2.29*** | (−3.52, −1.07) |
| Insomnia (SCI-08)a | ||||||||
| Baseline | 42 | 12.71 | 6.62 | 41 | 12.37 | 7.75 | ||
| Week 4 | 38 | 12.71 | 6.06 | 30 | 19.13 | 8.27 | 5.38*** | (2.56, 8.20) |
| Anxiety (GAD-2) | ||||||||
| Baseline | 42 | 3.07 | 1.81 | 41 | 3.83 | 1.80 | ||
| Week 4 | 38 | 2.84 | 1.79 | 30 | 2.07 | 1.91 | −0.93* | (−1.68, −0.17) |
| Depression (PHQ-2) | ||||||||
| Baseline | 42 | 2.26 | 1.82 | 41 | 2.76 | 1.48 | ||
| Week 4 | 38 | 1.92 | 1.62 | 30 | 1.53 | 1.50 | −0.52 | (−1.23, 0.19) |
| Post-trauma distress (IES-R total) | ||||||||
| Baseline | 43 | 2.17 | 0.71 | 41 | 2.24 | 0.77 | ||
| Week 4 | 38 | 1.70 | 0.56 | 32 | 0.83 | 0.58 | −0.8*** | (−1.08, −0.53) |
| Post-trauma distress (IES-R intrusion subscale) | ||||||||
| Baseline | 43 | 2.43 | 0.80 | 41 | 2.52 | 0.91 | ||
| Week 4 | 38 | 1.86 | 0.67 | 32 | 0.87 | 0.63 | −0.95*** | (−1.27, −0.62) |
| Post-trauma distress (IES-R avoidance subscale) | ||||||||
| Baseline | 43 | 2.22 | 0.83 | 41 | 2.19 | 0.81 | ||
| Week 4 | 38 | 1.95 | 0.70 | 32 | 1.06 | 0.75 | −0.75*** | (−1.09, −0.42) |
| Post-trauma distress (IES-R hyperarousal subscale) | ||||||||
| Baseline | 43 | 1.83 | 0.93 | 41 | 2.03 | 0.96 | ||
| Week 4 | 38 | 1.27 | 0.68 | 32 | 0.53 | 0.52 | −0.7*** | (−0.97, −0.44) |
| Work Functioning | ||||||||
| Work Engagement (SWEBO)a | ||||||||
| Baseline | 42 | 2.19 | 0.53 | 40 | 2.03 | 0.46 | ||
| Week 4 | 38 | 2.10 | 0.48 | 28 | 2.59 | 0.66 | 0.46*** | (0.20, 0.71) |
| Work Burnout (SWEBO) | ||||||||
| Baseline | 42 | 2.33 | 0.50 | 40 | 2.45 | 0.54 | ||
| Week 4 | 38 | 2.40 | 0.61 | 28 | 1.80 | 0.54 | −0.61*** | (−0.87, −0.34) |
| Sickness Absence (number of sick days over past four weeks) | ||||||||
| Baseline | 42 | 3.21 | 6.62 | 40 | 3.80 | 6.91 | ||
| Week 4 | 38 | 3.45 | 7.61 | 28 | 3.79 | 7.36 | 1.50b | (0.64, 3.51) |
| Intention to leave job | ||||||||
| Baseline | 42 | 9.19 | 3.62 | 40 | 8.65 | 3.79 | ||
| Week 4 | 38 | 10.32 | 3.35 | 28 | 9.36 | 4.63 | −0.86 | (−2.20, 0.49) |
| Wellbeing | ||||||||
| Quality of Life (EQ-5D-5L Scale Score)a | ||||||||
| Baseline | 42 | 67.83 | 19.30 | 40 | 66.03 | 19.40 | ||
| Week 4 | 38 | 65.13 | 21.51 | 28 | 78.68 | 13.52 | 12.32** | (4.61, 20.04) |
| General functioning (WHODAS 2.0) | ||||||||
| Baseline | 42 | 21.88 | 14.96 | 40 | 25.00 | 15.23 | ||
| Week 4 | 38 | 22.37 | 14.40 | 28 | 13.54 | 11.94 | −9.78*** | (−15.06, −4.50) |
| Impact of participant-identified problems (PSYCHLOPS) | ||||||||
| Baseline | 42 | 13.29 | 2.94 | 40 | 14.20 | 3.30 | ||
| Week 4 | 38 | 12.13 | 3.57 | 30 | 6.97 | 4.78 | −6.49*** | (−8.48, −4.51) |
| Intrusive Memory Ratings | ||||||||
| How distressing were your intrusive memories?c | ||||||||
| Baseline | 43 | 6.00 | 1.83 | 42 | 6.02 | 1.83 | ||
| Week 4 | 38 | 5.53 | 1.94 | 35 | 2.86 | 2.45 | −2.63*** | (−3.72, −1.54) |
| How much did they disrupt your concentration?c | ||||||||
| Baseline | 43 | 6.70 | 1.88 | 42 | 7.05 | 2.29 | ||
| Week 4 | 38 | 5.95 | 1.72 | 35 | 2.74 | 2.76 | −3.21*** | (−4.28, −2.15) |
| How much did they interfere with what you were doing?c | ||||||||
| Baseline | 43 | 5.42 | 2.30 | 42 | 5.95 | 2.26 | ||
| Week 4 | 38 | 5.13 | 1.99 | 35 | 2.26 | 2.32 | −2.92*** | (−3.90, −1.95) |
| How much did your intrusive memories affect your work functioning?c | ||||||||
| Baseline | 43 | 4.53 | 2.75 | 42 | 4.71 | 2.64 | ||
| Week 4 | 38 | 3.97 | 2.81 | 35 | 1.71 | 2.63 | −2.15*** | (−3.22, −1.08) |
| How much did your intrusive memories affect your functioning in other areas of your life?c | ||||||||
| Baseline | 43 | 5.30 | 2.53 | 42 | 5.55 | 2.21 | ||
| Week 4 | 38 | 4.42 | 2.78 | 35 | 1.89 | 2.35 | −2.59*** | (−3.67, −1.51) |
Treatment effects presented for between-arm comparisons of secondary outcomes at week 4 (clinical symptoms, work functioning, wellbeing, and intrusive memory ratings). Mean (SD), and number N at baseline, and week 4 are also presented.
ITT Intention to treat, SD standard deviation, PCL-5 PTSD Checklist for DSM-5 (4-item version), SCI-08 Sleep Condition Indicator (8-item version), GAD-2 Generalised Anxiety Disorder Assessment (2-item version), PHQ-2 Patient Health Questionnaire (2-item version), IES-R Impact of Event Scale - Revised, SWEBO Scale of Work Engagement and Burnout, ITL Intention to Leave Job, WHODAS 2.0 World Health Organization Disability Assessment Schedule 12-item version, EQ-5D-5L European Quality of Life Five Dimension Five Level Scale, PSYCHLOPS Psychological Outcome Profiles Questionnaire.
*p ≤ 0.05; **p ≤ 0.01; ***p ≤ 0.001;
aHigher score on these measures indicates better functioning (i.e., better sleep, greater work engagement and better quality of life).
bFor sickness absence, the treatment effect estimate is the Incidence Rate Ratio rather than the mean difference.
cIndicates an item where responses were made on an 11-point scale where 0 = not at all to 10 = extremely or very much.