Summary of findings 1. Internet‐based cognitive and behavioural therapy (I‐C/BT) compared to wait list for post‐traumatic stress disorder (PTSD) in adults.
| I‐C/BT compared to wait list for PTSD in adults | ||||||
| Patient or population: adults with PTSD Setting: Intervention: I‐C/BT Comparison: wait list | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk with wait list | Risk with I‐C/BT | |||||
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Severity of PTSD symptoms (measured with the IES‐R, CAPS‐5, PCL‐CPSS‐I and PDS; higher score = worse outcome) Follow‐up: post‐treatment |
The mean severity of PTSD symptoms (post‐treatment) was 0 | SMD 0.6 lower (0.97 lower to 0.24 lower) | — | 560 (8 RCTs) | ⊕⊝⊝⊝ Very lowa,b | — |
| Dropouts | Study population | RR 1.39 (1.03 to 1.88) | 585 (8 RCTs) | ⊕⊕⊝⊝ Lowa | — | |
| 186 per 1000 | 258 per 1000 (192 to 350) | |||||
| Diagnosis of PTSD after treatment | Study population | RR 0.53 (0.28 to 1.00) | 62 (1 RCT) | ⊕⊝⊝⊝ Very lowc,d | — | |
| 548 per 1000 | 291 per 1000 (154 to 548) | |||||
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Severity of depressive symptoms (measured with the BDI, PHQ and CES‐D; higher score = worse outcome) Follow‐up: post‐treatment |
The mean depression (post‐treatment) was 0 | SMD 0.61 lower (1.17 lower to 0.05 lower) | — | 425 (5 RCTs) | ⊕⊝⊝⊝ Very lowb,e | — |
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Severity of anxiety symptoms (measured with the BAI and GAD‐7; higher score = worse outcome) Follow‐up: post‐treatment |
The mean anxiety (post‐treatment) was 0 | SMD 0.67 lower (0.98 lower to 0.36 lower) | — | 305 (4 RCTs) | ⊕⊝⊝⊝ Very lowf,g | — |
| Cost‐effectiveness | — | — | — | — | — | Not measured |
| Adverse events | — | — | — | — | — | Not measured |
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). BAI: Beck Anxiety Inventory; BDI: Beck Depression Inventory; CAPS‐5: Clinician‐Administered PTSD Symptom Scale; CES‐D: Center for Epidemiologic Studies Depression Scale; CI: confidence interval; GAD‐7: Generalized Anxiety Disorder 7‐Item Scale; I‐C/BT: Internet‐based cognitive and behavioural therapy; IES‐R: Impact of Event Scale; PCL‐CPSS‐I: PTSD Checklist‐Child Posttraumatic Stress Scale – Interview for DSM‐5; PDS: Posttraumatic Diagnostic Scale; PHQ: Patient Health Questionnaire; PTSD: post‐traumatic stress disorder;RCT: randomised controlled trial; RR: risk ratio; SMD: standardised mean difference. | ||||||
| GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect. | ||||||
aDowngraded two levels due to high risk of performance bias in all eight studies, high risk of attrition bias in two studies (Knaevelsrud 2015; Krupnick 2017), and high risk of other bias in three studies (Ivarsson 2014; Krupnick 2017; Lewis 2017).
bDowngraded one level for inconsistency; high levels of heterogeneity.
cDowngraded one level for imprecision due to small sample size and the CI around the effect estimate includes both little or no effect.
dDowngraded two levels due high risk of performance bias and other bias (Ivarsson 2014).
eDowngraded two levels due to high risk of performance bias in all five studies, high risk of attrition bias in one study (Krupnick 2017), and high risk of other bias in two studies (Krupnick 2017; Lewis 2017).
fDowngraded one level for imprecision due to small sample size.
gDowngraded two levels due to high risk or performance bias in all four studies, high risk of attrition bias in one study (Knaevelsrud 2015), and high risk of other bias in two studies (Lewis 2017; Spence 2011).