Table 4.
Assessment of the statistical association between predisposing factors and side effects of COVID-19 vaccines using χ2 tests.
| Post-Vaccination Side Effects | Statistical Values | Predisposing Factors | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Gender | Age | Education Level | Being a Healthcare Worker | Country | Type of COVID-19 Vaccine | Number of Doses | Suffering from Chronic Diseases | Being Smoker | Suffering from Food and/or Drug Allergies | Experiencing COVID-19 Vaccine Hesitancy and Related Fears before Vaccination | Experiencing COVID-19 Infection before Vaccination | ||
| Tiredness | χ2 | 348.81 | 216.92 | 50.86 | 3.48 | 470.66 | 381.94 | 23.71 | 48.16 | 5.88 | 10.41 | 214.27 | 59.66 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.062 | 0.000 | 0.000 | 0.000 | 0.000 | 0.015 | 0.001 | 0.000 | 0.000 | |
| Anxiety, depression and sleep disorders | χ2 | 93.64 | 98.68 | 26.43 | 5.54 | 298.51 | 162.81 | 3.97 | 35.31 | 0.57 | 11.31 | 318.11 | 55.97 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.019 | 0.000 | 0.000 | 0.046 | 0.000 | 0.452 | 0.001 | 0.000 | 0.000 | |
| Fever | χ2 | 66.59 | 114.72 | 15.32 | 9.05 | 492.59 | 706.12 | 57.02 | 21.30 | 3.72 | 11.58 | 84.99 | 13.84 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.003 | 0.000 | 0.000 | 0.000 | 0.019 | 0.054 | 0.001 | 0.000 | 0.000 | |
| Headache | χ2 | 243.11 | 107.78 | 27.07 | 0.01 | 307.95 | 271.56 | 32.42 | 30.95 | 3.70 | 27.64 | 176.27 | 39.54 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.910 | 0.000 | 0.000 | 0.000 | 0.001 | 0.054 | 0.000 | 0.000 | 0.000 | |
| Haziness or lack-of-clarity in eyesight | χ2 | 64.72 | 30.74 | 12.97 | 15.70 | 215.74 | 66.93 | 1.13 | 46.56 | 3.49 | 16.80 | 171.83 | 9.72 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.002 | 0.000 | 0.000 | 0.000 | 0.287 | 0.000 | 0.062 | 0.000 | 0.000 | 0.002 | |
| Injection site pain and swelling | χ2 | 387.31 | 181.27 | 61.68 | 5.79 | 461.47 | 508.68 | 7.11 | 35.63 | 9.89 | 15.91 | 132.81 | 29.94 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.016 | 0.000 | 0.000 | 0.008 | 0.000 | 0.002 | 0.000 | 0.000 | 0.000 | |
| Joint pain | χ2 | 187.85 | 122.97 | 22.08 | 4.04 | 389.40 | 327.40 | 42.95 | 63.59 | 0.09 | 16.66 | 189.04 | 38.26 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.045 | 0.000 | 0.000 | 0.000 | 0.000 | 0.761 | 0.000 | 0.000 | 0.000 | |
| Swollen ankles and feet | χ2 | 117.35 | 22.95 | 7.01 | 18.60 | 120.82 | 7.89 | 1.43 | 124.63 | 0.71 | 10.89 | 112.60 | 6.18 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.030 | 0.000 | 0.000 | 0.246 | 0.231 | 0.000 | 0.400 | 0.001 | 0.000 | 0.013 | |
| Myalgia | χ2 | 179.21 | 138.21 | 39.27 | 1.63 | 368.75 | 321.06 | 32.88 | 41.58 | 0.24 | 10.39 | 159.93 | 19.34 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.201 | 0.000 | 0.000 | 0.000 | 0.000 | 0.627 | 0.001 | 0.000 | 0.000 | |
| Nausea | χ2 | 274.59 | 72.92 | 16.38 | 3.50 | 104.42 | 83.96 | 0.44 | 28.65 | 4.53 | 25.38 | 155.06 | 20.94 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.061 | 0.000 | 0.000 | 0.507 | 0.001 | 0.033 | 0.000 | 0.000 | 0.000 | |
| Abdominal pain | χ2 | 134.48 | 72.89 | 9.14 | 14.43 | 151.04 | 44.69 | 4.51 | 34.72 | 0.08 | 13.60 | 142.77 | 33.27 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.010 | 0.000 | 0.000 | 0.000 | 0.034 | 0.000 | 0.778 | 0.000 | 0.000 | 0.000 | |
| Diarrhea | χ2 | 33.21 | 43.37 | 4.60 | 17.71 | 143.62 | 22.58 | 2.51 | 30.88 | 0.05 | 5.38 | 78.07 | 39.61 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.100 | 0.000 | 0.000 | 0.001 | 0.113 | 0.001 | 0.828 | 0.020 | 0.000 | 0.000 | |
| Vomiting | χ2 | 41.27 | 20.50 | 2.55 | 0.60 | 51.06 | 53.68 | 0.00 | 6.06 | 0.00 | 12.34 | 22.14 | 3.52 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.279 | 0.438 | 0.000 | 0.000 | 0.966 | 0.810 | 0.972 | 0.000 | 0.000 | 0.061 | |
| Bruises on the body | χ2 | 90.06 | 20.69 | 5.77 | 2.05 | 101.13 | 33.58 | 0.01 | 24.71 | 0.03 | 12.77 | 35.97 | 15.82 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.056 | 0.152 | 0.000 | 0.000 | 0.906 | 0.006 | 0.854 | 0.000 | 0.000 | 0.000 | |
| Bleeding gums | χ2 | 1.50 | 3.49 | 0.88 | 1.13 | 28.95 | 12.13 | 2.12 | 52.34 | 0.02 | 9.50 | 29.27 | 0.21 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.220 | 0.322 | 0.643 | 0.288 | 0.049 | 0.059 | 0.146 | 0.000 | 0.876 | 0.002 | 0.000 | 0.650 | |
| Nosebleed | χ2 | 0.00 | 2.34 | 0.54 | 3.22 | 60.02 | 8.73 | 6.98 | 27.03 | 5.36 | 1.45 | 148.50 | 2.15 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.983 | 0.504 | 0.763 | 0.073 | 0.000 | 0.190 | 0.008 | 0.003 | 0.021 | 0.229 | 0.000 | 0.143 | |
| Chills | χ2 | 158.18 | 102.65 | 16.33 | 0.97 | 433.68 | 454.30 | 77.70 | 37.08 | 0.04 | 13.95 | 87.51 | 11.70 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.325 | 0.000 | 0.000 | 0.000 | 0.000 | 0.840 | 0.000 | 0.000 | 0.001 | |
| Itchy skin, or irritation and allergic reactions | χ2 | 58.98 | 12.02 | 0.60 | 12.36 | 92.68 | 18.55 | 0.18 | 52.73 | 0.81 | 59.50 | 81.86 | 9.47 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.007 | 0.739 | 0.000 | 0.000 | 0.005 | 0.669 | 0.000 | 0.369 | 0.000 | 0.000 | 0.002 | |
| Sweating for no reason | χ2 | 37.25 | 28.36 | 8.14 | 10.11 | 155.91 | 177.94 | 0.85 | 45.68 | 14.80 | 21.38 | 144.52 | 39.40 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.017 | 0.001 | 0.000 | 0.000 | 0.356 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | |
| Cold, numbness and tingling in limbs | χ2 | 109.93 | 64.64 | 20.86 | 8.64 | 192.88 | 199.45 | 0.09 | 38.75 | 0.64 | 19.52 | 231.80 | 16.26 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.003 | 0.000 | 0.000 | 0.758 | 0.000 | 0.424 | 0.000 | 0.000 | 0.000 | |
| Dizziness | χ2 | 285.06 | 94.20 | 25.85 | 11.04 | 335.10 | 145.06 | 1.50 | 27.40 | 5.69 | 16.35 | 56.85 | 29.22 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.001 | 0.000 | 0.000 | 0.221 | 0.002 | 0.017 | 0.000 | 0.000 | 0.000 | |
| Clogged nose | χ2 | 32.47 | 37.68 | 11.81 | 1.52 | 148.96 | 31.09 | 0.00 | 35.31 | 1.00 | 19.87 | 40.92 | 18.33 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.003 | 0.218 | 0.000 | 0.000 | 0.986 | 0.000 | 0.317 | 0.000 | 0.000 | 0.000 | |
| Runny nose | χ2 | 37.74 | 18.53 | 5.57 | 0.21 | 93.77 | 17.16 | 0.01 | 41.96 | 0.08 | 19.64 | 101.46 | 14.23 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.062 | 0.645 | 0.000 | 0.009 | 0.940 | 0.000 | 0.774 | 0.000 | 0.000 | 0.000 | |
| Dyspnea | χ2 | 64.95 | 44.31 | 16.76 | 10.40 | 176.86 | 43.71 | 0.83 | 44.31 | 0.95 | 20.91 | 119.88 | 15.16 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.001 | 0.000 | 0.000 | 0.363 | 0.000 | 0.329 | 0.000 | 0.000 | 0.000 | |
| Chest pain | χ2 | 33.30 | 57.66 | 13.37 | 12.47 | 246.59 | 59.47 | 0.28 | 53.52 | 2.46 | 22.91 | 208.47 | 24.24 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.001 | 0.000 | 0.000 | 0.000 | 0.599 | 0.000 | 0.117 | 0.000 | 0.000 | 0.000 | |
| Sleepiness and laziness | χ2 | 284.72 | 173.50 | 38.46 | 4.84 | 309.15 | 135.99 | 7.45 | 34.98 | 1.01 | 11.35 | 204.67 | 35.19 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.028 | 0.000 | 0.000 | 0.006 | 0.000 | 0.315 | 0.001 | 0.000 | 0.000 | |
| Irregular heartbeats | χ2 | 117.55 | 56.90 | 12.73 | 4.63 | 306.14 | 86.46 | 0.72 | 70.05 | 0.42 | 33.00 | 101.57 | 32.87 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.002 | 0.031 | 0.000 | 0.000 | 0.396 | 0.000 | 0.515 | 0.000 | 0.000 | 0.000 | |
| Abnormal blood pressure | χ2 | 56.78 | 17.41 | 12.73 | 3.43 | 199.35 | 57.09 | 0.31 | 114.06 | 0.81 | 12.57 | 148.15 | 12.59 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.001 | 0.002 | 0.064 | 0.000 | 0.000 | 0.579 | 0.000 | 0.367 | 0.000 | 0.000 | 0.000 | |
| Sore or dry throat | χ2 | 102.02 | 43.03 | 16.45 | 23.87 | 213.90 | 52.52 | 5.43 | 36.76 | 0.01 | 34.92 | 49.70 | 31.62 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 1 | 1 | |
| p | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.020 | 0.000 | 0.917 | 0.000 | 0.000 | 0.000 | |
| Cough | χ2 | 22.65 | 27.59 | 14.40 | 2.63 | 112.21 | 21.98 | 0.57 | 41.05 | 0.15 | 15.67 | 227.95 | 4.36 |
| DF | 1 | 3 | 2 | 1 | 18 | 6 | 1 | 10 | 1 | 1 | 3 | 1 | |
| p | 0.000 | 0.000 | 0.001 | 0.105 | 0.000 | 0.001 | 0.451 | 0.000 | 0.694 | 0.000 | 0.000 | 0.037 | |
| Severity of post-vaccination side effects | χ2 | 345.78 | 199.75 | 32.52 | 0.46 | 788.45 | 888.54 | 36.81 | 72.85 | 11.86 | 28.11 | 214.27 | 40.93 |
| DF | 3 | 9 | 6 | 3 | 54 | 18 | 3 | 30 | 3 | 3 | 1 | 3 | |
| p | 0.000 | 0.000 | 0.000 | 0.928 | 0.000 | 0.000 | 0.000 | 0.000 | 0.008 | 0.000 | 0.000 | 0.000 | |
χ2, chi-square; DF, degree of freedom; p, p-value (significant at ≤0.01).