Table 2.
Comparison of groups at follow-upa (N=931).
| Characteristics | Intervention (n=402) | Control (n=529) | Pb | ||
| Characteristics unlikely to have changed since baseline |
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Gender, n (%)c |
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Male | 198 (49.3) | 276 (52.2) | .38 |
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Female | 204 (50.7) | 253 (47.8) |
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Age (years), n (%)c |
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<18 | 62 (15.4) | 81 (15.3) | .60 |
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18-20 | 271 (67.4) | 366 (69.2) |
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21-25 | 49 (12.2) | 65 (12.3) |
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26-30 | 20 (5.0) | 17 (3.2) |
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Faculty of study, n (%)c |
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Science and engineering | 128 (31.8) | 168 (31.8) | .90 |
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Humanities | 213 (53.0) | 286 (54.1) |
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Medical | 61 (15.2) | 75 (14.2) |
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Language used, n (%)c |
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Swedish | 387 (96.3) | 511 (96.6) | .79 |
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English | 15 (3.7) | 18 (3.4) |
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Domestic status, n (%) |
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Living alone without kids at home | 267 (66.4) | 360 (68.1) | .06 |
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Living alone with kids at home | 3 (0.7) | 1 (0.2) |
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Living with somebody without kids | 74 (18.4) | 101 (19.1) |
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Living with somebody with kids | 15 (3.7) | 6 (1.1) |
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Have a partner but not living together | 43 (10.7) | 61 (11.5) |
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Domestic status (3 categories), n (%) |
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Living alone | 270 (67.2) | 361 (68.2) | .75 |
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Living with somebody | 89 (22.1) | 107 (20.2) |
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Have a partner but not living together | 43 (10.7) | 61 (11.5) |
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Weight (kg), mean (SD)d | 71.53 (13.35) | 70.92 (12.24) |
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| Characteristics specific to follow-up |
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Device used, n (%) |
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Mobile phone | 85 (21.1) | 129 (24.4) | .39 |
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Laptop | 302 (75.1) | 376 (71.1) |
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Tablet | 15 (3.7) | 24 (4.5) |
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Time to follow-up (hours), median (IQR) | 71 (279) | 48 (207) | 0.31 | |
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Number of follow-up emails before response, n (%) |
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1 | 222 (55.2) | 315 (59.6) | .07e |
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2 | 82 (20.4) | 103 (19.5) |
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3 | 51 (12.7) | 70 (13.2) |
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4 | 27 (6.7) | 23 (4.3) |
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5 | 20 (5.0) | 18 (3.4) |
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a Without university of Gävle; this is the population used for the primary analyses in Table 3.
b All P-values were provided for heterogeneity except for variable number of follow-up emails. Determined using chi-square test (gender, age, faculty, language, domestic status 3 categories), Fisher exact test (domestic status), Student’s t test (weight), Wilcoxon rank sum test (time to follow-up), or linear trend test (number of follow-up emails).
c Regarded as baseline variables in the analysis.
d Intervention: n=401; control: n=528.
e Trend test.