Background
Methods
Study design and population
In- and exclusion criteria
Measurements
Statistical analysis
Results
Demographics and internet use
Normal internet users (N = 173) | Problematic internet users (N = 58) |
p
| ||
---|---|---|---|---|
Sex | Male | 69 (39.9%) | 21 (36.2%) | 0.10a |
Female | 104 (60.1%) | 35 (60.3%) | ||
Transgender | 0 | 2 (3.4) | ||
Age | Mean, years (standard deviation) | 43.6 (12.7) | 35.9 (11.9) | <0.001b** |
20–29 | 26 (15.0%) | 23 (39.7%) | ||
30–39 | 37 (21.4%) | 14 (24.1%) | ||
40–49 | 60 (34.7%) | 12 (20.7%) | ||
50–59 | 29 (16.8%) | 6 (10.3%) | ||
60–69 | 16 (9.2%) | 3 (5.2%) | ||
70–79 | 5 (2.9%) | 0 | ||
Education (highest level) | Junior high school | 8 (4.6%) | 5 (8.6%) | 0.59a |
High school | 57 (32.9%) | 23 (39.7%) | ||
Junior college | 25 (14.5%) | 6 (10.3%) | ||
University | 76 (43.9%) | 22 (37.9%) | ||
Graduate school | 7 (4.0%) | 2 (3.4%) | ||
Employment status | Employed/homemaker/studying | 113 (65.3%) | 29 (50.0%) | 0.04c* |
Unemployed | 60 (34.7%) | 29 (50.0%) | ||
Living situation | With others | 138 (79.8%) | 47 (81.0%) | 0.84c |
Alone | 35 (20.2%) | 11 (19.0%) | ||
Marital status | Married/living together | 67 (38.7%) | 17 (29.3%) | 0.20c |
Unmarried/divorced/separated/widowed | 106 (61.3%) | 41 (70.7%) | ||
Diagnosis | ICD-10 F1 | 4 (2.3%) | 1 (1.7%) | 0.79c |
ICD-10 F2 | 20 (11.6%) | 6 (10.3%) | 0.80c | |
ICD-10 F3 | 56 (32.4%) | 17 (29.3%) | 0.66c | |
ICD-10 F4 | 94 (54.3%) | 37 (63.8%) | 0.21c | |
ICD-10 F5 | 13 (7.5%) | 3 (5.2%) | 0.54c | |
Clinical Global Impression-Severity | Median (interquartile range) | 3 (3–4) | 4 (3–4) | 0.009b* |
Psychiatry scale scores
Normal internet users (N = 173) | Problematic internet users (N = 58) | p (Mann–Whitney U test) | |
---|---|---|---|
Athens Insomnia Scale | 6.3 (4.5) | 8.8 (4.8) | <0.001* |
Beck Depression Inventory | 18.3 (12.7) | 27.4 (11.9) | <0.001* |
State-trait Anxiety Inventory (State) | 49.3 (12.1) | 54.0 (12.0) | 0.013 |
State-trait Anxiety Inventory (Trait) | 53.9 (11.0) | 61.8 (8.5) | <0.001* |
Adult ADHD Self-report Scale part A | 1.8 (1.5) | 3.1 (1.6) | <0.001* |
Adult ADHD Self-report Scale part B | 1.8 (2.3) | 3.5 (2.5) | <0.001* |
Autism Spectrum Quotient | 21.6 (7.1) | 25.9 (7.1) | <0.001* |
Obsessive-compulsive Inventory | 36.3 (31.7) | 63.2 (34.1) | <0.001* |
Liebowitz Social Anxiety Scale | 54.0 (33.9) | 71.4 (32.2) | <0.001* |
Alcohol Use Disorders Identification Test | 3.2 (4.4) | 4.3 (5.5) | 0.357 |
Barratt Impulsiveness Scale | 63.5 (8.2) | 67.4 (8.2) | 0.004* |
Sleep habits
Internet activities
Activities | Normal internet users, n (%) (N = 173) | Problematic internet users, n (%) (N = 58) | p (Mann–Whitney U test) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
None | <30 m | 30 m-1 h | 1 h–3 h | 3 h–5 h | >5 h | None | <30 m | 30 m-1 h | 1 h–3 h | 3 h–5 h | >5 h | ||
Work | 51(29.5) | 40(23.1) | 31(17.9) | 26(15.0) | 11(6.4) | 14(8.1) | 25(43.1) | 10(17.2) | 6(10.3) | 6(10.3) | 4(6.9) | 7(12.1) | 0.300 |
Private | 10(5.8) | 23(13.3) | 27(15.6) | 69(39.9) | 26(15.0) | 18(10.4) | 6(10.3) | 1(1.7) | 3(5.2) | 12(20.7) | 7(12.1) | 29(50.0) | <0.001* |
Other results
Age | Smartphone use frequency | Normal internet users, n (%) (N = 173) | Problematic internet users, n (%) (N = 58) | p (Fisher’s exact test) |
---|---|---|---|---|
Total (N = 231) | I don’t use it at all | 48 (27.7) | 13 (22.4) | <0.001** |
I hardly use it | 8 (4.6) | 1 (1.7) | ||
I sometimes use it | 21 (12.1) | 0 | ||
I often use it | 40 (23.1) | 2 (3.4) | ||
I use it really often | 56 (32.4) | 42 (72.4) | ||
20–29 (N = 49) | I don’t use it at all | 2 (7.7) | 2 (8.7) | 0.016* |
I hardly use it | 1 (3.8) | 0 | ||
I sometimes use it | 2 (7.7) | 0 | ||
I often use it | 8 (30.8) | 1 (4.3) | ||
I use it really often | 13 (50.0) | 20 (87.0) | ||
30–39 (N = 51) | I don’t use it at all | 5 (13.5) | 3 (21.4) | 0.12 |
I hardly use it | 3 (8.1) | 0 | ||
I sometimes use it | 2 (5.4) | 0 | ||
I often use it | 9 (24.3) | 0 | ||
I use it really often | 18 (48.6) | 11 (78.6) | ||
40–49 (N = 72) | I don’t use it at all | 20 (33.3) | 4 (33.3) | 0.14 |
I hardly use it | 3 (5.0) | 0 | ||
I sometimes use it | 11 (18.3) | 0 | ||
I often use it | 12 (20.0) | 1 (8.3) | ||
I use it really often | 14 (23.3) | 7 (58.3) | ||
50–59 (N = 35) | I don’t use it at all | 7 (24.1) | 2 (33.3) | 0.29 |
I hardly use it | 1 (3.4) | 1 (16.7) | ||
I sometimes use it | 3 (10.3) | 0 | ||
I often use it | 9 (31.0) | 0 | ||
I use it really often | 9 (31.0) | 3 (50.0) | ||
60–69 (N = 19) | I don’t use it at all | 9 (56.3) | 2 (66.7) | 1.00 |
I hardly use it | 0 | 0 | ||
I sometimes use it | 3 (18.8) | 0 | ||
I often use it | 2 (12.5) | 0 | ||
I use it really often | 2 (12.5) | 1 (33.3) | ||
70 < (N = 5) | I don’t use it at all | 5 (100.0) | 0 | 1.00 |
I hardly use it | 0 | 0 | ||
I sometimes use it | 0 | 0 | ||
I often use it | 0 | 0 | ||
I use it really often | 0 | 0 |