Background
Methods
Study eligibility
Study selection
Data extraction
Assessment of methodological quality
Assessing the effects of internet-based interventions for eating disorders
Results
Study selection
Methodological quality
Items | Study | Ljotsson et al. [16] | Robinson & Serfaty [[17] | Johnston et al. [15] | Carrard et al. [12] | Sanchez-Ortiz et al. [19] | Fernandez-Aranda et al. [14] | Carrard et al. [13] | Ruwaard et al. [18] |
---|---|---|---|---|---|---|---|---|---|
Methodological quality | |||||||||
Were the eligible criteria specified? | yes | yes | yes | yes | yes | no | yes | yes | |
Was the method of randomization described? | yes | yes | no | yes | yes | yes | yes | yes | |
Were the groups similar at baseline regarding important prognostic indicators? | yes | yes | unknown | yes | yes | yes | yes | yes | |
Were the index and the control interventions explicitly described? | yes | yes | yes | yes | yes | yes | yes | yes | |
Was the outcome assessor blinded to the interventions? | Unknown | yes | Unknown | no | yes | Unknown | no | Unknown | |
Was the dropout rate described and were the characteristics of dropouts compared with the completers? | yes | yes | yes | yes | yes | yes | No (no comparison) | no | |
Was long-term follow-up in the groups comparable? | no | no | yes | yes | no | no | yes | yes | |
Was the timing of the outcome measurements in the groups comparable? | yes | yes | yes | yes | yes | no | yes | yes | |
Was the sample size of each group described by means of a power calculation? | no | yes | yes | yes | yes | no | no | yes | |
Did the analysis include intention-to-treat analysis? | yes | yes | no | yes | yes | Unknown | no | yes | |
Were point estimates and measures of variability presented for the primary outcome measures? | yes | Mean but no standard deviation | yes | yes | yes | Mean but no standard deviation | yes | yes |
Methods
Authors | Ljotsson et al. [16] | Robinson & Serfaty [17] | Johnston et al. [15] | Carrard et al. [12] | Sanchez-Ortiz et al. [19] | Fernandez-Aranda et al. [14] | Carrard et al. [13] | Ruwaard et al. [18] |
---|---|---|---|---|---|---|---|---|
Type of study/
Randomisation
| RCT: based on generated random numbers; Stratification procedure was implemented with regard to diagnosis and severity | RCT: randomization was based on generated random numbers | RCT: No exact description was given | RCT: Randomization was based on generated random numbers | RCT: based on generated random numbers; Stratification procedure was implemented with regard to diagnosis and recruitment site | CT: participants were consecutively assigned to either the treatment group or the control group | CT: participants were either offered to take part in the treatment program or asked to participate in the control group during information session for WLT | RCT: randomization was based on generated random numbers |
Intervention
| Self- help based on CBT using the Swedish translation of the book “Overcoming Binge Eating” | Email therapy based on CBT working on a model of the eating disorder | 20 minutes writings on the basis of the Pennebaker task | Guided self-help treatment program consisting of 11 modules based on CBT targeting behavioural and psychological aspects of BED | guided self-help treatment program “Overcoming Bulimia Online” consisting of eight sessions based on CBT | Guided self-help program introducing CBT and psychoeducational concepts in seven sequential stepsc | Guided self-help program and consisting of 11 modules based on CBT targeting behavioural and psychological aspects of BED | Guided self-help program referring to CBT main principles for treatment of BN |
Anonymity
| No: EDE interview was performed as main assessment | Yes: no interview or face-to-face meeting was conducted | Yes: no interview or face-to-face meeting was conducted | three additional face-to-face evaluations during a year | introduction in a face-to-face meeting or as telephone assessment | No: two face-to-face evaluations with their coaches during therapy | no: three additional face-to-face evaluations | Yes: only an interview with a diagnostician |
Lengths
| 12 weeks | Three months | Three days | Six months | 8 to 12 weeks | Four months | Six months | 20 weeks |
Frequency of contact
| One to two email contacts per week | On average two emails per week were expected | No contact at all during therapy | Weekly e-mail contact during the intervention phase; monthly e-mail contact during the follow-up period | Therapists sent emails once every one to two weeks and responded to any email received | Weekly e-mail contact with their coach during intervention phase | Therapists sent weekly e-mails and participants had to write at least one email each week to their coaches | Treatment includes 25 scheduled therapist feedback moments |
Number and diagnosis of participants
| 73 participants with full or sub-threshold Bulimia Nervosa (BN) or Binge Eating Disorder (BED) diagnosis according to DSM-IV; sub-threshold BN was defined as episodes of binge eating and compensatory behaviour at least twice-monthly for the last three months. BED participants needed to have at least two OBEs per month for the last six months | 97 participants suffering from BN (n = 36 purging; n =15 non-purging), BED (n = 26) or EDNOS (n = 20) diagnosis according to DSM-IV | 94 participants suffering from BN; Participants were required to score at or above the medium-range cut off for bulimic symptomatology | 74 participants suffering from BED (n = 43) or sub-threshold BED (n = 31) diagnosis according to DSM-IV; for sub-threshold BED participants needed to have at least one OBE weekly for the last three months | 76 students suffering from BN (n = 39) or EDNOS (n = 37) diagnosis according to DSM-IV; persons suffering from BED were excluded | 62 participants suffering from BN purging subtype; diagnosis according to DSM-IV | 42 obese participants suffering from BED (n = 21) or sub-threshold BED (n = 21); diagnosis according to DSM-IV; Frequency of binges had to be at least for once a month during the last three months | 105 participants suffering from BN symptoms (80% engaged in purging behaviour) |
A formal diagnosis of BN was not an inclusion criteria. Participants had to report recurrent binge eating, inappropriate weight-control behaviour and elevated concern with body shape and weight | ||||||||
Women N (%)
| 69 (97.3%) | 93 (95.9%) | 71 (75.5%) | 74 (100%) | 75 (98.7%) | 62 (100%) | 42 (100%) | 104 (99%) |
Age of participants M (SD)
| Intervention Group: 35.5 (11.4) | Whole sample: 24.5 (23–25.9) | Whole sample: 28.9 (9.8) | Whole sample: 36 (11.4) | Whole sample: 23.9 (5.69) | Whole sample: 23.7 (3.6) | Intervention Group: 44.6 (11.4) | Online-CBT: 30 (10) |
Control group: 33.7 (9.3) | Control group: 41.0 (8.2) | Bibliotherapy: 31 (9) | ||||||
Waiting list group: 32 (11) |
Authors | Ljotsson et al. [16] | Robinson & Serfaty [17] | Johnston et al. [15] | Carrard et al. [12] | Sanchez-Ortiz et al. [19] | Fernandez-Aranda et al. [14] | Carrard et al. [13] | Ruwaard et al. [18] |
---|---|---|---|---|---|---|---|---|
Control group
| Waiting list (n = 36) with assessment at mid-treatment and short weekly reports on eating behaviour | Unsupported self directed writing (n = 34). Waiting list control (n = 27) | Superficial writing control group (n = 46) | Waiting list control group (n = 37) with monthly email contact during waiting period | Waiting list control group (n = 38) | Waiting list (n = 31) for 12 weeks keeping a food diary, recording binge eating and purging episodes | Waiting list control group (n = 20), waiting for a weight loss treatment | Waiting list control group (n = 35). Bibliotherapy (n = 35) |
Measures
| EDE-Q | BITE | BITE | EDE-Q | EDE | EDI | EDE-Q | EDE-Q |
EDI-2 | EDI-2 | BITE | ||||||
Food Diary | ||||||||
Assessments
| Pre-treatment | Baseline | Baseline | Baseline | Baseline | Baseline | Baseline | Baseline |
Post-treatment | Post-treatment | Four weeks follow-up | Post-treatment | Post-treatment | Post-treatment | Post-tretament | Post-tretament | |
Six month follow-up | Eight weeks follow-up | Six month follow-up | Three month follow-up | Six month follow-up | 12 month follow-up | |||
Treatment dropout
| 31.4% | 47.2% | 16.7% | 24.3% | 21.1% | 45.0% | 9% | 25.7% |
Study dropout
| 2.9% | 37.1% | 14.9% | 17.6% | 11.8% | n.a. | 4.8% | 21.0% |
Definition of abstinence
| no episodes of binge eating or purging during the 28 days prior to the post-treatment assessment | Criteria for an eating disorder are no longer fulfilled | Participants not falling within the clinical range of the BITE total score | Abstinence from OBEs as measured by the EDE-Q for the last 28 days | Lack of vomiting and laxative abuse abstinence from OBEs over a month long period | Abstinence of binges and vomits: no information about duration available | No binge episode over the last three months | No binge or purging episode over the last 28 days according to EDE-Q |
Rate of abstinence
(Intervention group)
| 37% | 23.5% | 23.7% (at baseline) to 35% (at 8 week follow-up) | 35.1% | 25.8% | 22.6% | 45% | Bingeing: 57% (at baseline) to 94% at post-treatment |
Purging: 60% (at baseline) to 100% at post-treatment | ||||||||
Rate of abstinence
(Control group)
| 15% | 0.0% | n.a. | 8.1% | 13.9% | 0% | 15% | Bingeing: 77% (at baseline) to 86% at post-treatment |
Purging: 83% (at baseline) to 89% at post-treatment |
Participants’ characteristics
Intervention characteristics
Control group characteristics
Outcomes
Outcomes related to eating disorders
Ljotsson et al. [16] | Johnston et al. [15] | Carrard et al. [12] | Sanchez-Ortiz et al. [19] | Fernandez-Aranda et al. [14] | Carrard et al. [13] | Ruwaard et al. [18] | ||
---|---|---|---|---|---|---|---|---|
Primary outcome
| ||||||||
Binge episodes | ESwithin(CI 95%) |
0.98 (0.58-1.38)
|
1.05 (0.65-1.45)
|
0.75 (0.39-1.11)
|
0.90 (0.40-1.40)
|
1.05 (0.63-1.47)
| ||
ESbetween(CI 95%) |
0.52 (0.04-1.00)
|
0.52 (0.06-0.98)
| 0.35 (-0.10-0.80) | 0.49 | 0.20 (-0.41-0.81) | 0.43 (-0.04-0.90) | ||
Purging | ESwithin(CI 95%) |
0.41 (0.06-0.76)
|
0.
56
(0.
22-
0.
90)
|
0.
77
(0.
39-
1.
15)
| ||||
ESbetween(CI 95%) |
1.63 (1.08-2.18)
| 0.27 (-0.18-0.72) | 0.45 (-0.02-0.92) | |||||
Vomiting | ESwithin(CI 95%) |
0.46 (0.12-0.80)
| ||||||
ESbetween(CI 95%) | 0.29 (-0.16-0.74) |
0.
78
| ||||||
Secondary Outcome
| ||||||||
EDE-Q
| ||||||||
Restraint | ESwithin(CI 95%) | 0.32 (-0.02-0.66) |
0.47 (0.13-0.81)
|
1.26 (0.83-1.69)
| 0.23 (-0.19-0.65) | |||
ESbetween(CI 95%) | 0.26 (-0.21-0.73) | 0.14 (-0.32-0.60) |
0.79 (0.32-1.26)
| 0.24 (-0.37-0.85) | ||||
Eating concern | ESwithin(CI 95%) |
0.86 (0.47-1.25)
|
1.05 (0.65-1.45)
|
0.78 (0.30-1.26)
| ||||
ESbetween(CI 95%) |
0.99 (0.49-1.49)
|
0.84 (0.37-1.31)
| 0.39 (-0.22-1.00) | |||||
Shape concern | ESwithin(CI 95%) |
0.51 (0.16-0.86)
|
0.89 (0.51-1.27)
|
1.02 (0.63-1.41)
|
1.02 (0.50-1.54)
| |||
ESbetween(CI 95%) |
0.92 (0.42-1.42)
| 0.28 (-0.18-0.74) |
1.05 (0.57-1.53)
| 0.58 (-0.04-1.20) | ||||
Weight concern | ESwithin(CI 95%) |
0.78 (0.40-1.16)
|
0.73 (0.37-1.09)
|
1.11 (0.57-1.65)
| ||||
ESbetween(CI 95%) |
1.10 (0.59-1.61)
|
0.79 (0.32-1.26)
| 0.18 (-0.43-0.79) | |||||
Total | ESwithin(CI 95%) |
0.71 (0.34-1.08)
|
1.18 (0.76-1.60)
|
1.21 (0.79-1.63)
|
0.79 (0.31-1.27)
|
1.
18
(0.
75-
1.
61)
| ||
ESbetween(CI 95%) |
0.
96
(0.
46-
1.
46)
| 0.45 (-0.01-0.91) |
1.
09
(0.
61-
1.
57)
| 0.32 (-0.29-0.93) |
0.50 (0.02-0.98)
| |||
EDI
(-2)
| ||||||||
Drive for thinness | ESwithin(CI 95%) |
0.
55
(0.
19-
0.
91)
|
0.
62
(0.
27-
0.
97)
| |||||
ESbetween(CI 95%) |
0.
99
(0.
49-
1.
49)
|
0.
48
(0.
02-
0.
94)
| 0.25 | |||||
Body dissatisfaction | ESwithin(CI 95%) |
0.
39
(0.
05-
0.
73)
|
0.
60
(0.
25-
0.
95)
| |||||
ESbetween(CI 95%) |
0.
76
(0.
27-
1.
25)
| 0.05 (-0.41-0.51) | 0.16 | |||||
Interoceptive awareness | ESwithin(CI 95%) |
0.
70
(0.
33-
1.
07)
|
0.
53
(0.
18-
0.
88)
| |||||
ESbetween(CI 95%) |
0.
88
(0.
39-
1.
37)
|
0.
46
(0.
00-
0.
92)
| 0.03 | |||||
Bulimia | ESwithin(CI 95%) |
0.
79
(0.
41-
1.
17)
|
1.
56
(1.
08-
2.
04)
| |||||
ESbetween(CI 95%) |
0.
94
(0.
44-
1.
44)
|
1.
08
(0.
59-
1.
57)
| 0.54 | |||||
Interpersonal distrust | ESwithin(CI 95%) | 0.02 (-0.31-0.35) | 0.21 (-0.12-0.54) | |||||
ESbetween(CI 95%) | 0.00 (-0.47-0.47) | 0.17 (-0.29-0.63) | 0.32 | |||||
Ineffectiveness | ESwithin(CI 95%) |
0.
47
(0.
12-
0.
82)
|
0.
36
(0.
03-
0.
69)
| |||||
ESbetween(CI 95%) |
0.
57
(0.
09-
1.
05)
| 0.33 (-0.13-0.79) | 0.05 | |||||
Maturity fears | ESwithin(CI 95%) | 0.23 (-0.10-0.56) | ||||||
ESbetween(CI 95%) | 0.15 (-0.31-0.61) |
0.
63
| ||||||
Perfectionism | ESwithin(CI 95%) | 0.21 (-0.13-0.55) | 0.12 (-0.20-0.44) | |||||
ESbetween(CI 95%) | 0.22 (-0.25-0.69) | 0.19 (-0.27-0.65) | 0.13 | |||||
Impulse regulation | ESwithin(CI 95%) |
0.
51
(0.
17-
0.
85)
| ||||||
ESbetween(CI 95%) | 0.31 (-0.15-0.77) | |||||||
Social insecurity | ESwithin(CI 95%) |
0.
64
(0.
29-
0.
99)
| ||||||
ESbetween(CI 95%) | 0.27 (-0.19-0.73) | |||||||
Total | ESbetween(CI 95%) | 0.37 | ||||||
BITE
| ||||||||
Severity | ESwithin(CI 95%) | 0.14 (-0.14-0.42) | ||||||
ESbetween(CI 95%) | 0.28 (-0.13-0.69) | |||||||
Symptom | ESwithin(CI 95%) | 0.10 (-0.18-0.38) | ||||||
ESbetween(CI 95%) | 0.03 (-0.37-0.43) | |||||||
Total | ESwithin(CI 95%) | 0.14 (-0.14-0.42) | ||||||
ESbetween(CI 95%) | 0.13 (-0.28-0.54) |
1.
03
|
Primary outcomes
Secondary outcomes
Dropout rates
Stability of results
Additional outcomes
Ljotsson et al. [16] | Johnston et al. [15] | Carrard et al. [12] | Sanchez-Ortiz et al. [19] | Carrard et al. [13] | ||
---|---|---|---|---|---|---|
Depression
| ||||||
BDI (-II) | ESwithin (CI 95%) |
0.
61
(0.
26-
0.
96)
|
0.
61
(0.
15-
1.
07)
| |||
ESbetween (CI 95%) | 0.37 (-0.09-0.83) |
0.
80
(0.
17-
1.
43)
| ||||
HADS | ESwithin (CI 95%) | 0.08 (-0.20-0.36) |
2.
18
(1.
59-
2.
77)
| |||
ESbetween (CI 95%) | 0.18 (-0.23-0.59) |
0.
97
(0.
49-
1.
45)
| ||||
MADRS | ESwithin (CI 95%) |
0.
78
(0.
40-
1.
16)
| ||||
ESbetween (CI 95%) |
0.
76
(0.
27-
1.
14)
| |||||
Anxiety
| ||||||
HADS | ESwithin (CI 95%) | 0.27 (-0.02-0.56) |
1.
01
(0.
62-
1.
40)
| |||
ESbetween (CI 95%) | 0.02 (-0.38-0.42) |
0.
82
(0.
33-
1.
31)
| ||||
Quality of life
| ||||||
IWQOL-Lite
| ||||||
Physical functioning | ESwithin (CI 95%) |
0.
44
(0.
00-
0.
88)
| ||||
ESbetween (CI 95%) | 0.37 (-0.24-0.98) | |||||
Self-esteem | ESwithin (CI 95%) |
0.
55
(0.
10-
1.
00)
| ||||
ESbetween (CI 95%) | 0.59 (-0.03-1.21) | |||||
Sexual life | ESwithin (CI 95%) |
0.
49
(0.
05-
0.
93)
| ||||
ESbetween (CI 95%) |
0.
84
(0.
21-
1.
47)
| |||||
Public distress | ESwithin (CI 95%) |
0.
52
(0.
07-
0.
97)
| ||||
ESbetween (CI 95%) |
0.
73
(0.
10-
1.
36)
| |||||
Work | ESwithin (CI 95%) | 0.43 (-0.01-0.87) | ||||
ESbetween (CI 95%) |
0.
94
(0.
30-
1.
58)
| |||||
Total score | ESwithin (CI 95%) | 0.30 (-0.03-0.63) |
0.
68
(0.
21-
1.
15)
| |||
ESbetween (CI 95%) | 0.01 (-0.45-0.47) |
0.
78
(0.
15-
1.
41)
| ||||
WHOQOL-Bref
| ||||||
Physical health | ESwithin (CI 95%) |
1.
01
(0.
62-
1.
40)
| ||||
ESbetween (CI 95%) |
1.
03
(0.
55-
1.
51)
| |||||
Psychological health | ESwithin (CI 95%) |
0.
77
(0.
41-
1.
13)
| ||||
ESbetween (CI 95%) |
0.
80
(0.
33-
1.
27)
| |||||
Social | ESwithin (CI 95%) |
0.
67
(0.
32-
1.
02)
| ||||
ESbetween (CI 95%) |
0.
65
(0.
19-
1.
11)
| |||||
Enviromental | ESwithin (CI 95%) | 0.15 (-0.17-0.47) | ||||
ESbetween(CI 95%) | 0.19 (-0.26-0.64) | |||||
SWLS | ||||||
Total | ESwithin (CI 95%) |
0.
41
(0.
06-
0.
76)
| ||||
ESbetween (CI 95%) | 0.31 (-0.17-0.79) |