Table 2.
Summary of findings and confidence in effect estimates for the prevention studies.
| Outcome | k | N | Effect size (95% CI) | Heterogeneity (% I2) | Confidence in effect estimates (GRADE) |
|---|---|---|---|---|---|
| CBT-based e-intervention (‘Student Bodies’ program) for the prevention of any eating disorder versus waitlist control | |||||
| Weight concern | |||||
| End of intervention | 8 | 836 | SMD −0.30 (−0.61 to 0.01) | 75 | Lowa, b, c |
| Subgroup analysis | |||||
|
5 | 269 | SMD −0.21 (−0.45 to 0.03) | 0 | Lowa, c, d |
|
3 | 567 | SMD −0.37 (−0.96 to 0.21) | 88 | Lowa, b, c |
| Follow-up | 8 | 819 | SMD −0.30 (−0.47 to −0.13)* | 20 | Moderatea, c |
| Shape concern | |||||
| End of intervention | 6 | 425 | SMD −0.08 (−0.27 to 0.12) | 3 | Moderatea, c |
| Follow-up | 6 | 400 | SMD −0.17 (−0.37 to 0.03) | 0 | Moderatea, c |
| Dietary restraint | |||||
| End of intervention | 4 | 316 | SMD −0.27 (−0.64 to 0.09) | 60 | Lowa, c, d |
| Follow-up | 4 | 299 | SMD −0.37 (−0.61 to −0.14)* | 5 | Lowa, c, d |
| Drive for thinness | |||||
| End of intervention | 8 | 841 | SMD −0.37 (−0.59 to −0.15)* | 50 | Moderatea, b, c |
| Subgroup analysis | |||||
|
5 | 277 | SMD −0.33 (−0.64 to −0.02)* | 38 | Lowa, c, d |
|
3 | 564 | SMD −0.40 (−0.74 to −0.06)* | 66 | Lowa, b, c |
| Follow-up | 8 | 816 | SMD −0.37 (−0.51 to −0.22)* | 2 | Moderatea, c |
| Bulimia | |||||
| End of intervention | 7 | 739 | SMD −0.01 (−0.24 to 0.22) | 44 | Moderatea, c |
| Follow-up | 7 | 722 | SMD −0.13 (−0.36 to 0.09) | 41 | Moderatea, c |
| Global eating disorder psychopathology | |||||
| End of intervention | 3 | 573 | SMD −0.23 (−0.79 to 0.32) | 87 | Lowa, b, c |
| Follow-up | 3 | 556 | SMD −0.33 (−0.58 to −0.07)* | 39 | Moderatea, c |
| Binge eating | |||||
| End of intervention | 1 | 115 | SMD −0.28 (−0.65 to 0.08) | NA | Lowc, d |
| Follow-up | 1 | 103 | SMD −0.43 (−0.82 to −0.04)* | NA | Lowc, d |
| Vomiting and/or diuretic/laxative misuse | |||||
| End of intervention | 1 | 115 | SMD −0.21 (−0.57 to 0.16) | NA | Lowc, d |
| Follow-up | 1 | 103 | SMD −0.33 (−0.72 to 0.06) | NA | Lowc, d |
| Remission from subthreshold eating disorders | |||||
| End of intervention | 1 | 115 | RR 0.75 (0.25 to 2.23) | NA | Lowc, d |
| Follow-up | 1 | 103 | RR 0.29 (0.06 to 1.34) | NA | Lowc, d |
| Cessation from binge eating, vomiting, laxative/diuretic misuse and restrictive eating | |||||
| End of intervention | 1 | 115 | RR 2.42 (1.27 to 4.62)* | NA | Lowc, d |
| Follow-up | 1 | 103 | RR 1.68 (0.98 to 2.88) | NA | Lowc, d |
| CBT-based e-intervention (‘Student Bodies’ program) for the prevention of any eating disorder versus classroom education | |||||
| Weight concern | |||||
| End of intervention | 1 | 39 | SMD 0.22 (−0.42 to 0.87) | NA | Lowa, d |
| Follow-up | 1 | 39 | SMD 0.20 (−0.44 to 0.85) | NA | Lowa, d |
| Shape concern | |||||
| End of intervention | 1 | 39 | SMD 0.25 (−0.40 to 0.90) | NA | Lowa, d |
| Follow-up | 1 | 39 | SMD 0.56 (−0.09 to 1.22) | NA | Lowa, d |
| Dietary restraint | |||||
| End of intervention | 1 | 39 | SMD 0.07 (−0.58 to 0.71) | NA | Lowa, d |
| Follow-up | 1 | 39 | SMD 0.07 (−0.58 to 0.71) | NA | Lowa, d |
| Drive for thinness | |||||
| End of intervention | 1 | 39 | SMD 0.21 (−0.44 to 0.86) | NA | Lowa, d |
| Follow-up | 1 | 39 | SMD −0.05 (−0.69 to 0.60) | NA | Lowa, d |
| Bulimia | |||||
| End of intervention | 1 | 39 | SMD 0.13 (−0.52 to 0.78) | NA | Lowa, d |
| Follow-up | 1 | 39 | SMD 0.04 (−0.60 to 0.69) | NA | Lowa, d |
| Psychoeducation-based e-intervention for the prevention of any eating disorder versus control | |||||
| Global eating disorder psychopathology | |||||
| Follow-up# | 1 | 112 | SMD −0.28 (−0.66 to 0.09) | NA | Lowa, d |
| Weight concern | |||||
| Follow-up# | 1 | 112 | SMD −0.28 (−0.66 to 0.09) | NA | Lowa, d |
| Shape concern | |||||
| Follow-up# | 1 | 112 | SMD −0.34 (−0.71 to 0.03) | NA | Lowa, d |
| Dietary restraint | |||||
| Follow-up# | 1 | 112 | SMD −0.26 (−0.64 to 0.11) | NA | Lowa, d |
| Cognitive dissonance based e-intervention for the prevention of any eating disorder versus control | |||||
| Global eating disorder psychopathology | |||||
| End of intervention | 1 | 48 | SMD 0.05 (−0.53 to 0.63) | NA | Moderated |
| Dietary restraint | |||||
| End of intervention | 1 | 48 | SMD −0.27 (−0.85 to 0.31) | NA | Moderated |
| Cognitive dissonance based e-intervention for the prevention of any eating disorder versus face-to-face group-based cognitive dissonance intervention | |||||
| Global eating disorder psychopathology | |||||
| End of intervention | 1 | 58 | SMD −0.13 (−0.68 to 0.42) | NA | Moderated |
| Dietary restraint | |||||
| End of intervention | 1 | 58 | SMD −0.14 (−0.69 to 0.41) | NA | Moderated |
| Motivational interviewing based e-intervention for the prevention of any eating disorder versus control | |||||
| Weight concern | |||||
| End of intervention | 1 | 212 | SMD −0.18 (−0.45 to 0.09) | NA | Lowa, d |
| Shape concern | |||||
| End of intervention | 1 | 212 | SMD −0.33 (−0.60 to −0.06)* | NA | Lowa, d |
| Dietary restraint | |||||
| End of intervention | 1 | 212 | SMD −0.38 (−0.66 to −0.11)* | NA | Lowa, d |
| Vomiting | |||||
| End of intervention | 1 | 212 | SMD −0.56 (−0.83 to −0.28)* | NA | Lowa, d |
| CBT-based e-intervention (‘Student Bodies’ program) for the prevention of binge eating disorder versus waitlist control | |||||
| Binge eating | |||||
| End of intervention | 1 | 105 | SMD 0.07 (−0.31 to 0.46) | NA | Lowa, c, d |
| Follow-up | 1 | 105 | SMD 0.38 (0.00 to 0.77)* | NA | Lowa, c, d |
| Weight concern | |||||
| End of intervention | 1 | 66 | SMD −0.28 (−0.77 to 0.20) | NA | Lowa, c, d |
| Follow-up | 1 | 66 | SMD 0.01 (−0.48 to 0.49) | NA | Lowa, c, d |
| Shape concern | |||||
| End of intervention | 1 | 66 | SMD −0.17 (−0.65 to 0.32) | NA | Lowa, c, d |
| Follow-up | 1 | 66 | SMD 0.13 (−0.35 to 0.61) | NA | Lowa, c, d |
| Dietary restraint | |||||
| End of intervention | 1 | 66 | SMD 0.45 (−0.04 to 0.94) | NA | Lowa, c, d |
| Follow-up | 1 | 66 | SMD 0.26 (−0.23 to 0.74) | NA | Lowa, c, d |
| Remission (BMI < 85th percentile, no longer at risk of BED) | |||||
| End of intervention | 1 | 87 | RR 2.35 (0.90 to 6.09) | NA | Lowa, c, d |
Note.
BED = binge eating disorder; BMI = body mass index; k = number of studies; N = number of participants; NA = not applicable; SMD = standardised mean difference; RR = risk ratio; CI = confidence interval.
*p < 0.05.
#Outcomes of relevance to the review were only reported at follow-up.
Reasons for downgrading, based on the GRADE approach:
a
Risk of bias (one or more of the following: selection bias, performance bias, detection bias, attrition bias, selective outcome reporting bias).
b
Inconsistency (I2 > 50%, p < 0.05).
c
Indirectness (comparison: waitlist control).
d
Imprecision (optimal information size for dichotomous outcomes = 300 events, and for continuous outcomes = 400 participants).