Introduction
Material and methods
Participants and recruitment
Eligibility criteria | Inclusion criteria | Exclusion criteria |
---|---|---|
Sex | Women | Men |
Age | 18–80 years | <18 years |
Body mass index (BMI) | Obesity grades I and II | Overweight, Obesity grade III |
Participation | Attendance of all program modules | Selection of single program module |
Informed consent | Written informed consent | Denial of written informed consent, denying permission to keep data after drop out |
Attendance | 70% attendance of face to face treatment, presence at assessment appointments | Long-term absence, missing assessment appointments |
Physical requirements | Fit for moderate exercise | Severe physical impairments prohibiting even light exercise, pregnancy |
Mental state/motivation | Mental stability, meeting group counselling requirements, motivation | Mental disorders with current symptoms, lack of motivation |
Technical requirements | Internet access, basic computer skills | No Internet access, no computer experience |
Validity | Study is the only current weight loss intervention | Simultaneous participation in additional weight reduction programs |
Intervention
Instruments
Measurements
Allocation
Characteristics |
p-value | WBI (n = 21) | PMI (n = 22) | ||
---|---|---|---|---|---|
Age, years, mean (SD)
|
0.84
|
48.1
|
(±8.3)
|
48.8
|
(±13.0)
|
Level of education, n (%)
|
0.60
|
–
|
–
|
–
|
–
|
Academic degree | – | 5 | 23.8 | 6 | 27.3 |
High school degree | – | 8 | 38.1 | 6 | 27.3 |
Grammar school | – | 7 | 33.3 | 10 | 45.5 |
Compulsory school | – | 1 | 4.8 | 0 | 0.0 |
Status of employment, n (%)
|
0.67
|
–
|
–
|
–
|
–
|
Full time job | – | 12 | 57.1 | 11 | 50.0 |
Part time job | – | 3 | 14.3 | 3 | 13.6 |
Retired | – | 3 | 14.3 | 6 | 27.3 |
Continuing education | – | 1 | 4.8 | 1 | 4.5 |
Maternity leave | – | 1 | 4.8 | 0 | 0.0 |
Unemployed | – | 1 | 4.8 | 0 | 0.0 |
Housewife | – | 0 | 0.0 | 1 | 4.5 |
Marital status, n (%)
|
0.52
|
–
|
–
|
–
|
–
|
Single, no partner | – | 4 | 19.0 | 4 | 18.2 |
In relationship | – | 5 | 23.8 | 1 | 4.5 |
Married | – | 8 | 38.1 | 10 | 45.5 |
Divorced | – | 3 | 14.3 | 6 | 27.3 |
Widowed | – | 1 | 4.8 | 1 | 4.5 |
Children, n (%)
|
0.74
|
–
|
–
|
–
|
–
|
No children | – | 10 | 47.6 | 8 | 36.4 |
One child | – | 6 | 28.6 | 7 | 31.8 |
Two children | – | 5 | 23.8 | 7 | 31.8 |
Single parent (with children <18 years), n (%)
|
0.58
|
1
|
4.8
|
2
|
9.1
|
Household income (net monthly), n (%)
|
0.56
|
–
|
–
|
–
|
–
|
<€ 600 | – | 2 | 9.5 | 0 | 0.0 |
€ 601–900 | – | 0 | 0.0 | 1 | 4.5 |
€ 901–1200 | – | 1 | 4.8 | 2 | 9.1 |
€ 1201–1500 | – | 5 | 23.8 | 3 | 13.6 |
€ 1501–1800 | – | 1 | 4.8 | 4 | 18.2 |
€ 1801–2200 | – | 4 | 19.0 | 4 | 18.2 |
€ 2201–2600 | – | 4 | 19.0 | 3 | 13.6 |
>€ 2600 | – | 4 | 19.0 | 5 | 22.7 |
BMI grade, n (%)
|
0.97
|
–
|
–
|
–
|
–
|
Overweight | – | 3 | 14.3 | 3 | 13.6 |
Obesity grade I | – | 9 | 42.9 | 11 | 50.0 |
Obesity grade II | – | 7 | 33.3 | 6 | 27.3 |
Obesity grade III | – | 2 | 9.5 | 2 | 9.1 |
Statistical analysis
Results
Domain | Time | Group | Usage | Meana
| SD | Group | Usage | Meanb
| SD | Main effects | 2-way interaction | 3-way interaction | ||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
P
Time |
P
Group |
P
Usage |
P
Time * Group |
P
Time * Usage |
P
Group * Usage |
P
Time * Group * Usage | ||||||||||
Self-efficacy negative emotions | 6 months | WBI | Yes (n = 14) | 7.46 | 1.26 | WBI | Yes (n = 14) | 0.00 | 1.49 | 0.814 | 0.958 | 0.614 | 0.381 | 0.532 | 0.597 | 0.208 |
No (n = 7) | 6.82 | 1.37 | ||||||||||||||
PMI | Yes (n = 13) | 7.10 | 1.57 | No (n = 7) | 0.29 | 1.58 | ||||||||||
No (n = 9) | 7.53 | 1.72 | ||||||||||||||
12 months | WBI | Yes (n = 14) | 7.46 | 1.86 | PMI | Yes (n = 13) | 0.17 | 1.39 | ||||||||
No (n = 7) | 7.11 | 1.66 | ||||||||||||||
PMI | Yes (n = 13) | 7.27 | 1.80 | No (n = 9) | −0.67 | 1.00 | ||||||||||
No (n = 9) | 6.86 | 1.95 | ||||||||||||||
Self-efficacy availability | 6 months | WBI | Yes (n = 14) | 6.80 | 2.13 | WBI | Yes (n = 14) | 0.02 | 1.63 | 0.237 | 0.837 | 0.095 | 0.620 | 0.139 | 0.629 | 0.786 |
No (n = 7) | 6.54 | 1.06 | ||||||||||||||
PMI | Yes (n = 13) | 6.90 | 1.69 | No (n = 7) | −0.75 | 0.99 | ||||||||||
No (n = 9) | 6.00 | 1.64 | ||||||||||||||
12 months | WBI | Yes (n = 14) | 6.82 | 2.02 | PMI | Yes (n = 13) | 0.12 | 1.18 | ||||||||
No (n = 7) | 5.79 | 1.56 | ||||||||||||||
PMI | Yes (n = 13) | 7.02 | 1.67 | No (n = 9) | −0.42 | 1.36 | ||||||||||
No (n = 9) | 5.58 | 2.02 | ||||||||||||||
Self-efficacy social pressure | 6 months | WBI | Yes (n = 14) | 6.93 | 2.24 | WBI | Yes (n = 14) | 0.50 | 2.00 | 0.915 | 0.821 | 0.495 | 0.682 | 0.105 | 0.618 | 0.438 |
No (n = 7) | 7.39 | 1.30 | ||||||||||||||
PMI | Yes (n = 13) | 7.17 | 1.75 | No (n = 7) | −0.64 | 1.43 | ||||||||||
No (n = 9) | 6.69 | 2.03 | ||||||||||||||
12 months | WBI | Yes (n = 14) | 7.43 | 1.98 | PMI | Yes (n = 13) | 0.33 | 0.83 | ||||||||
No (n = 7) | 6.75 | 2.24 | ||||||||||||||
PMI | Yes (n = 13) | 7.50 | 1.63 | No (n = 9) | −0.08 | 1.22 | ||||||||||
No (n = 9) | 6.61 | 2.22 | ||||||||||||||
Self-efficacy physical discomfort | 6 months | WBI | Yes (n = 14) | 7.59 | 1.07 | WBI | Yes (n = 14) | 0.14 | 1.07 | 0.940 | 0.896 | 0.586 | 0.296 | 0.231 | 0.292 | 0.504 |
No (n = 7) | 7.71 | 0.68 | ||||||||||||||
PMI | Yes (n = 13) | 6.98 | 1.59 | No (n = 7) | −0.57 | 1.47 | ||||||||||
No (n = 9) | 7.81 | 1.48 | ||||||||||||||
12 months | WBI | Yes (n = 14) | 7.73 | 1.56 | PMI | Yes (n = 13) | 0.29 | 1.42 | ||||||||
No (n = 7) | 7.14 | 1.94 | ||||||||||||||
PMI | Yes (n = 13) | 7.27 | 1.95 | No (n = 9) | 0.08 | 0.63 | ||||||||||
No (n = 9) | 7.89 | 1.45 | ||||||||||||||
Self-efficacy positive activities | 6 months | WBI | Yes (n = 14) | 7.27 | 1.67 | WBI | Yes (n = 14) | 0.41 | 1.19 | 0.698 | 0.572 | 0.783 | 0.402 | 0.141 | 0.950 | 0.710 |
No (n = 7) | 7.68 | 0.77 | ||||||||||||||
PMI | Yes (n = 13) | 7.67 | 1.33 | No (n = 7) | −0.25 | 0.60 | ||||||||||
No (n = 9) | 8.00 | 0.90 | ||||||||||||||
12 months | WBI | Yes (n = 14) | 7.68 | 1.43 | PMI | Yes (n = 13) | −0.02 | 1.15 | ||||||||
No (n = 7) | 7.43 | 1.12 | ||||||||||||||
PMI | Yes (n = 13) | 7.65 | 1.19 | No (n = 9) | −0.42 | 1.21 | ||||||||||
No (n = 9) | 7.58 | 1.39 | ||||||||||||||
General nutrition self-efficacy | 6 months | WBI | Yes (n = 14) | 7.21 | 1.40 | WBI | Yes (n = 14) | 0.21 | 1.17 | 0.638 | 0.958 | 0.565 | 0.938 | 0.091 | 0.920 | 0.844 |
No (n = 7) | 7.23 | 0.85 | ||||||||||||||
PMI | Yes (n = 13) | 7.17 | 1.26 | No (n = 7) | −0.39 | 0.97 | ||||||||||
No (n = 9) | 7.21 | 1.43 | ||||||||||||||
12 months | WBI | Yes (n = 14) | 7.42 | 1.56 | PMI | Yes (n = 13) | 0.17 | 0.85 | ||||||||
No (n = 7) | 6.84 | 1.47 | ||||||||||||||
PMI | Yes (n = 13) | 7.34 | 1.35 | No (n = 9) | −0.30 | 0.81 | ||||||||||
No (n = 9) | 6.91 | 1.57 |
Domain | Time | Group | Usage | Meana
| SD | Group | Usage | Meanb
| SD | Main effects | 2-way interaction | 3-way interaction | ||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
P
Time |
P
Group |
P
Usage |
P
Time * Group |
P
Time * Usage |
P
Group * Usage |
P
Time * Group * Usage | ||||||||||
Self-efficacy active lifestyle | 6 months | WBI | Yes (n = 14) | 3.50 | 0.43 | WBI | Yes (n = 14) | 0.12 | 0.41 | 0.042 | 0.858 | 0.486 | 0.616 | 0.010 | 0.115 | 0.158 |
No (n = 7) | 3.48 | 0.33 | ||||||||||||||
PMI | Yes (n = 13) | 3.36 | 0.46 | No (n = 7) | −0.53 | 0.74 | ||||||||||
No (n = 9) | 3.59 | 0.43 | ||||||||||||||
12 months | WBI | Yes (n = 14) | 3.62 | 0.37 | PMI | Yes (n = 13) | −0.03 | 0.48 | ||||||||
No (n = 7) | 2.95 | 0.71 | ||||||||||||||
PMI | Yes (n = 13) | 3.33 | 0.69 | No (n = 9) | −0.22 | 0.37 | ||||||||||
No (n = 9) | 3.37 | 0.73 | ||||||||||||||
Self-efficacy start exercising | 6 months | WBI | Yes (n = 14) | 3.45 | 0.67 | WBI | Yes (n = 14) | −0.24 | 0.68 | 0.862 | 0.294 | 0.764 | 0.834 | 0.368 | 0.016 | 0.483 |
No (n = 7) | 2.79 | 0.91 | ||||||||||||||
PMI | Yes (n = 13) | 3.10 | 0.53 | No (n = 7) | 0.14 | 1.33 | ||||||||||
No (n = 9) | 3.44 | 0.62 | ||||||||||||||
12 months | WBI | Yes (n = 14) | 3.21 | 0.66 | PMI | Yes (n = 13) | −0.02 | 0.54 | ||||||||
No (n = 7) | 2.93 | 0.61 | ||||||||||||||
PMI | Yes (n = 13) | 3.08 | 0.66 | No (n = 9) | 0.03 | 0.29 | ||||||||||
No (n = 9) | 3.47 | 0.48 | ||||||||||||||
Self-efficacy keep up exercising | 6 months | WBI | Yes (n = 14) | 3.12 | 0.69 | WBI | Yes (n = 14) | −0.02 | 0.54 | 0.325 | 0.891 | 0.588 | 0.519 | 0.503 | 0.414 | 0.617 |
No (n = 7) | 3.08 | 0.21 | ||||||||||||||
PMI | Yes (n = 13) | 3.00 | 0.43 | No (n = 7) | −0.04 | 0.53 | ||||||||||
No (n = 9) | 3.34 | 0.70 | ||||||||||||||
12 months | WBI | Yes (n = 14) | 3.10 | 0.74 | PMI | Yes (n = 13) | −0.03 | 0.49 | ||||||||
No (n = 7) | 3.04 | 0.55 | ||||||||||||||
PMI | Yes (n = 13) | 2.97 | 0.65 | No (n = 9) | −0.21 | 0.21 | ||||||||||
No (n = 9) | 3.13 | 0.77 | ||||||||||||||
Self-efficacy resume exercising | 6 months | WBI | Yes (n = 14) | 3.60 | 0.59 | WBI | Yes (n = 14) | −0.34 | 0.68 | 0.103 | 0.924 | 0.592 | 0.857 | 0.279 | 0.265 | 0.944 |
No (n = 7) | 3.38 | 0.52 | ||||||||||||||
PMI | Yes (n = 13) | 3.38 | 0.45 | No (n = 7) | −0.09 | 0.81 | ||||||||||
No (n = 9) | 3.52 | 0.71 | ||||||||||||||
12 months | WBI | Yes (n = 14) | 3.26 | 0.63 | PMI | Yes (n = 13) | −0.30 | 0.93 | ||||||||
No (n = 7) | 3.29 | 0.52 | ||||||||||||||
PMI | Yes (n = 13) | 3.08 | 0.77 | No (n = 9) | −0.04 | 0.26 | ||||||||||
No (n = 9) | 3.48 | 0.71 |