From: Lifestyle choices and mental health: a longitudinal survey with German and Chinese students
 | German students | Chinese students |  | ||||||
---|---|---|---|---|---|---|---|---|---|
 | n | M | SD | n | M | SD | t (df) | p | d |
Lifestyle factors | |||||||||
 Body mass index | 2981 | 22.88 | 3.87 | 11350 | 20.49 | 2.66 | 39.29 (14461) | < .001 | 0.65 |
 Physical activity (range: 0 to 4) | 2991 | 2.24 | 1.19 | 12405 | 2.38 | 1.05 | −6.36 (15394) | < .001 | 0.10 |
 Mental activity (range: 0 to 4) | 2991 | 2.72 | 1.10 | 12402 | 3.05 | 1.09 | −14.62 (15391) | < .001 | 0.24 |
 Alcohol frequency (range: 0 to 4) | 2991 | 1.43 | 1.00 | 12371 | 0.65 | .89 | 42.12 (15360) | < .001 | 0.68 |
 Social rhythm irregularity (range: 10 to 60) | 2991 | 29.58 | 9.01 | 12338 | 26.81 | 9.33 | 14.71 (15327) | < .001 | 0.24 |
 | n | % |  | n | % |  | χ2 | p | d |
 Smoking (% yes) | 608 | 20.3 |  | 1355 | 10.9 |  | 191.13 (1) | < .001 | 0.22 |
 Vegetarian diet (% yes) | 482 | 16.1 |  | 2734 | 22.2 |  | 55.45 (1) | < .001 | 0.12 |
 | n | M | SD | n | M | SD | t (df) | p | d |
Mental health at baseline | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 Positive mental health (range: 0 to 27) | 2979 | 18.13 | 5.46 | 12375 | 19.90 | 5.21 | −16.52 (15352) | < .001 | 0.27 |
 Mental health problems (range: 0 to 63) | 2624 | 15.17 | 10.98 | 12306 | 9.50 | 10.14 | 25.65 (14928) | < .001 | 0.42 |
 | n | M | SD | n | M | SD | t (df) | p | d |
Mental health at follow-up | |||||||||
 Positive mental health (range: 0 to 27) | 632 | 18.23 | 5.58 | 8920 | 20.15 | 5.30 | −8.79 (9550) | < .001 | 0.18 |
 Mental health problems (range: 0 to 63) | 600 | 14.16 | 10.53 | 8834 | 9.39 | 10.96 | 10.32 (9432) | < .001 | 0.21 |