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. 2020 Jul 8;11:3500. doi: 10.1038/s41467-020-17318-x

Table 3.

Univariable and multivariable analysis of factors associated with having detectable antibodies (IgM and/or IgG and/or IgA).

Univariable analysis Multivariable analysis
Negative (n = 524) Positive (n = 54) P value OR (95% CI) p value OR (95% CI) p value
Sexa Male 148 (28%) 13 (24%) 0.52b 1 0.52
Female 376 (72%) 41 (76%) 1.24 (0.65; 2.38)
Agec,d 42 (12) 40 (12) 0.11e 0.98 (0.96; 1.00) 0.11 0.98 (0.95; 1.00) 0.09f
Professional categorya Otherg 90 (17%) 8 (15%) 0.89b 1 0.89
Lab technician/other tech. 41 (8%) 4 (7%) 1.10 (0.31; 3.85)
Nurses/auxiliary nursesi 262 (50%) 26 (48%) 1.12 (0.49; 2.55)
Physicians 131 (25%) 16 (30%) 1.37 (0.56; 3.35)
Daily contact with patientsa No 113 (22%) 10 (19%) 0.60b 1 0.60
Yes 411 (78%) 44 (81%) 1.21 (0.59; 2.48)
Working in a COVID-19 unita No 284 (54%) 31 (57%) 0.65b 1 0.65
Yes 240 (46%) 23 (43%) 0.88 (0.50; 1.55)
Close contact with COVID-19 confirmed or suspected casea No 127 (24%) 10 (19%) 0.35b 1 0.35
Yes 397 (76%) 44 (81%) 1.41 (0.69; 2.88)
Previously diagnosed with COVID-19 by rRT-PCRa No 518 (99%) 21 (39%) <0.0001j 1 <0.0001
Yes 6 (1%) 33 (61%) 135.67 (51.27; 359.01)
Comorbiditiesa,h No 471 (90%) 46 (85%) 0.28b 1 0.29
Yes 53 (10%) 8 (15%) 1.55 (0.69; 3.45)
Household sizec,d 2.7 (1.2) 2.9 (1.1) 0.37e 1.11 (0.88; 1.41) 0.37 1.25 (0.96; 1.62) 0.09f
Received Flu vaccine (2019–2020 season)a No 309 (59%) 30 (56%) 0.63b 1 0.63
Yes 215 (41%) 24 (44%) 1.15 (0.65; 2.02)
Reporting COVID-19 compatible symptom within the previous monthsa No 357 (68%) 11 (20%) <0.0001b 1 <0.0001 1 <0.0001f
Yes 167 (32%) 43 (80%) 8.36 (4.20; 16.61) 8.84 (4.41; 17.73)

an (Column percentage).

bChi-squared test.

cArithmetic mean (SD) [n].

dOdds ratio per unit increase.

eT-test.

fWald test.

gIncludes, cleaning, kitchen and maintenance staff.

hComorbidities include: heart and liver disease, diabetes, chronic respiratory and renal disease, cancers and autoimmune, and other immunological disorders.

iIncludes strecher-bearer.

jFisher’s exact test.