Respondents’ characteristics and habits according to Impact of Event Scale-Revised score; 0–23 (normal), 24–32 (mild psychological impact), 33–36 (moderate psychological impact) and ≥37 (severe psychological impact)
| N | 0–23 | 24–32 | 33–36 | ≥37 | Combined | P value | |
| (n=2463) | (n=827) | (n=242) | (n=762) | (n=4294) | |||
| Age | 4294 | 27/40/55 | 26/37/53 | 25/33/49 | 25/33/47 | 26/37/53 | <0.001 |
| Gender | |||||||
| Female | 4294 | 52% (1279) | 73% (600) | 85% (205) | 83% (633) | 63% (2717) | <0.001 |
| Male | 48% (1184) | 27% (227) | 15% (37) | 17% (129) | 37% (1577) | ||
| Nationality | |||||||
| Other | 4294 | 1% (30) | 1% (12) | 1% (3) | 1% (10) | 1% (55) | 0.965 |
| Italian | 99% (2433) | 99% (815) | 99% (239) | 99% (752) | 99% (4239) | ||
| Region | |||||||
| High COVID-19 incidence | 4284 | 44% (1090) | 47% (385) | 48% (115) | 47% (357) | 45% (1947) | 0.377 |
| Low COVID-19 incidence | 56% (1370) | 53% (440) | 52% (127) | 53% (400) | 55% (2337) | ||
| Educational level | |||||||
| Secondary education | 4294 | 44% (1087) | 48% (397) | 50% (121) | 51% (390) | 46% (1995) | 0.009 |
| University education | 56% (1368) | 52% (430) | 50% (120) | 48% (369) | 53% (2287) | ||
| Primary education | 0% (8) | 0% (0) | 0% (1) | 0% (3) | 0% (12) | ||
| Working status | |||||||
| Active employee | 4294 | 70% (1720) | 66% (543) | 62% (151) | 65% (494) | 68% (2908) | 0.001 |
| Unemployed/Retired/Homemaker | 14% (349) | 14% (115) | 14% (34) | 13% (100) | 14% (598) | ||
| Student | 16% (394) | 20% (169) | 24% (57) | 22% (168) | 18% (788) | ||
| House type | |||||||
| Multifamily house | 4294 | 64% (1586) | 65% (538) | 76% (183) | 67% (512) | 66% (2819) | 0.003 |
| Single room apartment | 2% (49) | 2% (19) | 1% (2) | 3% (25) | 2% (95) | ||
| Single-family house | 34% (828) | 33% (270) | 24% (57) | 30% (225) | 32% (1380) | ||
| Garden | |||||||
| No | 4294 | 38% (935) | 43% (355) | 52% (126) | 49% (375) | 42% (1791) | <0.001 |
| Yes | 62% (1528) | 57% (472) | 48% (116) | 51% (387) | 58% (2503) | ||
| Nasopharyngeal swab | |||||||
| No | 2774 | 93% (1482) | 92% (454) | 93% (151) | 95% (491) | 93% (2578) | 0.418 |
| Yes | 7% (120) | 8% (37) | 7% (11) | 5% (28) | 7% (196) | ||
| Recent loss | |||||||
| No | 2759 | 91% (1458) | 87% (423) | 88% (139) | 87% (452) | 90% (2472) | 0.004 |
| Yes | 9% (137) | 13% (64) | 12% (19) | 13% (67) | 10% (287) | ||
| Living alone | |||||||
| No | 4294 | 88% (2170) | 89% (737) | 88% (214) | 87% (663) | 88% (3784) | 0.635 |
| Yes | 12% (293) | 11% (90) | 12% (28) | 13% (99) | 12% (510) | ||
| Pet | |||||||
| No | 4294 | 54% (1332) | 52% (426) | 63% (152) | 52% (397) | 54% (2307) | 0.014 |
| Yes | 46% (1131) | 48% (401) | 37% (90) | 48% (365) | 46% (1987) | ||
| Physical activity | |||||||
| No | 3991 | 53% (1220) | 58% (443) | 59% (132) | 61% (432) | 56% (2227) | <0.001 |
| Yes | 47% (1081) | 42% (317) | 41% (93) | 39% (273) | 44% (1764) | ||
| Dietary habits (weekly consumption) | |||||||
| Pasta, rice, cereals | 3987 | 5/7/10 | 6/7/10 | 5/7/10 | 5/7/10 | 5/7/10 | 0.560 |
| Cereal-based products | 3984 | 3/7/7 | 4/7/7 | 4/7/7 | 4/7/7 | 3/7/7 | 0.018 |
| Raw meat | 3985 | 2/3/4 | 2/3/4 | 2/3/4 | 2/3/4 | 2/3/4 | 0.150 |
| Cured meat | 3981 | 1/2/3 | 1/2/3 | 1/2/3 | 1/2/3 | 1/2/3 | 0.404 |
| Fish | 3985 | 1/2/2 | 1/2/2 | 1/1/2 | 1/2/2 | 1/2/2 | 0.443 |
| Milk and yoghurt | 3982 | 2/7/7 | 2/6/7 | 2/7/7 | 2/6/7 | 2/7/7 | 0.398 |
| Milk-based products | 3984 | 2/3/5 | 2/3/5 | 1/3/5 | 2/3/5 | 2/3/5 | 0.002 |
| Fruit | 3985 | 4/7/10 | 4/7/10 | 3/7/14 | 3/7/8.75 | 4/7/10 | 0.003 |
| Dried fruit | 3981 | 0/2/5 | 0/2/5 | 0/1/5 | 0/2/4 | 0/2/5 | 0.061 |
| Vegetables | 3984 | 6/7/14 | 6/7/14 | 6/7/14 | 5/7/14 | 6/7/14 | 0.043 |
| Legumes | 3982 | 1/3/4 | 1/2/4 | 1/2/4 | 1/2/4 | 1/3/4 | 0.710 |
| Eggs | 3984 | 1/2/2 | 1/2/2 | 1/2/2 | 1/2/3 | 1/2/2 | 0.836 |
| Foods high in fat and sugar | 3980 | 1/3/6 | 2/3/6 | 2/4/7 | 2/4/7 | 2/3/7 | 0.012 |
| Soft drinks | 3979 | 0/0/1 | 0/0/1 | 0/0/1 | 0/0/2 | 0/0/1 | <0.001 |
| Alcoholic drinks (eg, wine, beer, spirits) | 3981 | 0/2/4 | 0/1/3 | 0/1/3 | 0/1/3 | 0/1/4 | <0.001 |
Data are percentages (absolute numbers) for categorical variables and I quartile/median/III quartile for continuous variables.