Table 2:

Odds of ever being tested for SARS-CoV-2 and of COVID-19 diagnosis in Ontario between Mar. 1 and June 20, 2020, in fully adjusted analyses using 2 analytic designs

DeterminantPeople tested for SARS-CoV-2People with a diagnosis of COVID-19*
Tested v. not tested adjusted OR (95% CI)Test-positive v. test-negative among all people tested adjusted OR (95% CI)Test-positive v. not test-positive§ adjusted OR (95% CI)
Sample size14 695 579758 69114 695 579
Individual determinant
Age group, yr (Ref. 0–4)
 5–191.15 (1.13–1.18)1.93 (1.66–2.24)1.72 (1.49–1.99)
 20–344.13 (4.05–4.22)2.00 (1.75–2.30)7.03 (6.13–8.05)
 35–494.13 (4.05–4.21)1.98 (1.73–2.27)6.74 (5.88–7.73)
 50–644.21 (4.12–4.29)2.02 (1.76–2.32)7.01 (6.11–8.03)
 65–743.04 (2.98–3.11)1.62 (1.40–1.87)3.99 (3.46–4.60)
 75–843.01 (2.95–3.08)1.64 (1.41–1.90)3.94 (3.39–4.57)
 ≥ 855.60 (5.47–5.73)1.76 (1.51–2.06)7.26 (6.23–8.46)
Male sex0.76 (0.76–0.76)1.26 (1.23–1.30)1.00 (0.98–1.03)
Living in rural area or small town0.97 (0.96–0.98)0.81 (0.74–0.88)0.76 (0.70–0.82)
Underlying chronic health condition
 Asthma1.09 (1.09–1.10)0.86 (0.83–0.89)0.92 (0.89–0.96)
 COPD1.23 (1.21–1.24)0.89 (0.82–0.96)1.04 (0.96–1.13)
 Hypertension0.98 (0.98–0.99)1.12 (1.08–1.16)1.13 (1.09–1.17)
 Diabetes0.98 (0.97–0.99)1.26 (1.21–1.31)1.19 (1.14–1.23)
 Congestive heart failure1.26 (1.24–1.28)0.99 (0.92–1.07)1.25 (1.16–1.35)
 Dementia or frailty score > 152.12 (2.09–2.15)1.39 (1.29–1.49)2.60 (2.42–2.80)
 Cancer1.13 (1.12–1.15)0.72 (0.66–0.80)0.86 (0.78–0.94)
 Chronic kidney disease**1.31 (1.29–1.32)0.86 (0.80–0.93)1.16 (1.08–1.24)
 Immunocompromised††1.30 (1.28–1.33)0.79 (0.70–0.89)1.02 (0.91–1.14)
 Advanced liver disease1.14 (1.11–1.16)0.79 (0.68–0.90)0.87 (0.76–1.00)
 Ischemic heart disease1.02 (1.01–1.03)0.88 (0.82–0.95)0.90 (0.84–0.97)
 Ischemic stroke or TIA‡‡1.15 (1.13–1.17)1.05 (0.95–1.17)1.18 (1.06–1.31)
 Schizophrenia§§1.24 (1.21–1.27)0.84 (0.73–0.97)0.99 (0.87–1.13)
 Substance abuse§§1.17 (1.16–1.19)0.72 (0.66–0.79)0.86 (0.79–0.95)
Health care use
Aggregated Diagnostic Group (ADG) quintile (Ref. = 0 ADGs)
 2 (1–2 ADGs)1.64 (1.62–1.66)0.78 (0.73–0.84)1.24 (1.17–1.32)
 3 (3–4 ADGs)2.07 (2.04–2.10)0.75 (0.70–0.80)1.46 (1.37–1.56)
 4 (5–6 ADGs)2.44 (2.41–2.48)0.74 (0.69–0.79)1.69 (1.57–1.81)
 5 (7–27 ADGs)3.11 (3.06–3.15)0.75 (0.69–0.80)2.12 (1.97–2.28)
Hospital admissions in the past 3 yr (Ref. = 0 admissions)
 10.99 (0.98–1.00)0.93 (0.89–0.97)0.92 (0.88–0.96)
 21.16 (1.14–1.17)0.86 (0.79–0.93)1.01 (0.94–1.09)
 ≥ 31.75 (1.73–1.78)0.82 (0.76–0.90)1.38 (1.27–1.50)
Outpatient physician visits in the past yr (Ref. = 0–1 visits)
 2–41.08 (1.07–1.09)1.02 (0.98–1.07)1.12 (1.08–1.18)
 5–81.11 (1.10–1.12)1.03 (0.98–1.08)1.17 (1.11–1.23)
 9–141.17 (1.16–1.18)0.98 (0.93–1.04)1.17 (1.10–1.24)
 ≥ 151.36 (1.34–1.37)0.91 (0.85–0.97)1.22 (1.14–1.30)
Influenza vaccination (2019–2020 season)1.08 (1.08–1.09)0.81 (0.78–0.83)0.87 (0.85–0.90)
Environmental determinants¶¶
PM2.5 category (μg/m3) (Ref. = 2–6)
 6–70.97 (0.97–0.98)0.91 (0.85–0.99)0.92 (0.85–0.99)
 7–80.92 (0.90–0.93)1.10 (0.99–1.21)1.00 (0.91–1.10)
  8–90.91 (0.90–0.93)1.29 (1.16–1.43)1.19 (1.08–1.32)
 ≥ 100.90 (0.89–0.92)1.45 (1.29–1.63)1.31 (1.16–1.47)
NO2 category (ppb) (Ref. = 0–6)
 6–80.95 (0.95–0.96)1.05 (1.00–1.11)1.00 (0.96–1.06)
 ≥ 80.94 (0.93–0.95)1.13 (1.06–1.21)1.05 (0.98–1.12)
Social determinant of health*** (area level)
Household density quintile††† (Ref. = first quintile)
 21.01 (1.00–1.02)1.21 (1.14–1.27)1.19 (1.13–1.26)
 31.03 (1.02–1.04)1.39 (1.31–1.48)1.42 (1.34–1.50)
 41.01 (1.00–1.02)1.70 (1.61–1.79)1.70 (1.61–1.80)
 50.97 (0.95–0.98)1.94 (1.82–2.07)1.86 (1.75–1.98)
Apartment building density category‡‡‡ (Ref. = first category)
 21.04 (1.03–1.04)1.00 (0.95–1.04)1.02 (0.98–1.06)
 31.01 (1.00–1.02)1.15 (1.09–1.21)1.18 (1.12–1.24)
Uncoupled quintile§§§ (Ref. = first quintile)
 21.02 (1.01–1.03)0.96 (0.91–1.01)0.97 (0.92–1.02)
 31.07 (1.06–1.08)0.95 (0.90–1.00)0.99 (0.94–1.04)
 41.19 (1.18–1.21)0.96 (0.91–1.02)1.11 (1.05–1.17)
 51.39 (1.38–1.41)1.07 (1.01–1.15)1.41 (1.32–1.51)
Essential work quintile¶¶¶ (Ref. = first category)
 21.04 (1.03–1.04)1.25 (1.19–1.32)1.30 (1.24–1.37)
 31.06 (1.05–1.07)1.28 (1.21–1.35)1.37 (1.30–1.45)
 41.05 (1.04–1.06)1.37 (1.29–1.45)1.51 (1.42–1.60)
 51.04 (1.03–1.06)1.42 (1.32–1.51)1.58 (1.48–1.69)
Household income quintile (Ref. = first quintile, lowest income)****
 21.03 (1.02–1.04)0.96 (0.91–1.00)1.00 (0.96–1.05)
 31.08 (1.07–1.09)1.02 (0.97–1.08)1.12 (1.06–1.18)
 41.10 (1.09–1.11)0.97 (0.90–1.03)1.06 (1.00–1.13)
 51.11 (1.09–1.12)0.97 (0.90–1.04)1.07 (0.99–1.15)
Limited educational attainment quintile†††† (Ref. = first quintile)
 21.03 (1.02–1.04)1.07 (1.02–1.12)1.09 (1.04–1.15)
 31.01 (1.00–1.02)1.15 (1.09–1.21)1.15 (1.09–1.21)
 41.02 (1.01–1.03)1.23 (1.17–1.30)1.21 (1.15–1.28)
 51.01 (1.00–1.02)1.37 (1.29–1.46)1.33 (1.26–1.41)
Visible minority quintile‡‡‡‡ (Ref. = first category)
 20.99 (0.98–1.00)0.96 (0.89–1.02)0.95 (0.89–1.02)
 30.95 (0.94–0.96)0.97 (0.91–1.05)0.93 (0.87–1.00)
 40.91 (0.90–0.92)1.07 (0.99–1.15)0.98 (0.91–1.06)
 50.86 (0.85–0.87)1.27 (1.17–1.38)1.09 (1.00–1.19)
Recent immigration category§§§§ (Ref. = first category)
 20.99 (0.99–1.00)1.04 (1.00–1.09)1.04 (1.00–1.08)
 30.94 (0.93–0.95)1.16 (1.11–1.22)1.10 (1.05–1.15)
  • Note: ADG = Aggregated Diagnostic Group, COPD = chronic obstructive pulmonary disease, OR = odds ratio, PM2.5 = fine particulate matter, Ref. = reference category, TIA = transient ischemic attack.

  • * All presented models are fully adjusted and contain all variables listed in this table as covariates.

  • Pseudo-test-negative design.

  • That is, all negative tests and all untested people.

  • § Case–control design.

  • We defined rural as being located outside the commuting zone of a city with population greater than 10 000.

  • ** We counted people if they had a diagnosis in the last 5 years.

  • †† We considered people to be immunocompromised if they were HIV positive, had an organ or bone marrow transplant, or had another immunodeficient condition.

  • ‡‡ This category includes people with ischemic stroke or TIA in the last 20 years.

  • §§ This category includes people with a diagnosis in the last 2 years.

  • ¶¶ Values of PM2.5 > 12 μg/m3 or NO2 > 53 ppb per year have been found to be associated with increased risk of other respiratory illnesses.52

  • *** All variables in this category are area-level variables at the level of the 2016 Canada Census dissemination area (DA).

  • ††† First quintile represents 0–2.1 people/dwelling; second quintile, 2.2–2.4 people/dwelling; third quintile, 2.5–2.6 people/dwelling; fourth quintile, 2.7–3 people/dwelling; and fifth quintile, 3.1–5.7 people/dwelling.

  • ‡‡‡ First category, 0%–7.3% of buildings in the area are apartment buildings; second category, 7.4%–37.7% are apartment buildings; and third category, 37.7%–100% are apartment buildings.

  • §§§ First quintile, 11.2%–33.7% of people are uncoupled; second quintile, 33.7%–38.4% of people; third quintile, 38.5%–43.6% of people; fourth quintile, 43.6%–51.0% of people; and fifth quintile, 51.0%–94.6% of people.

  • ¶¶¶ First quintile represents 0%–32.5% of working people in the area who self-identified as working in an essential job; second quintile, 32.5%–42.3% of people; third quintile, 42.3%–49.8% of people; fourth quintile, 50.0%–57.5% of people; and fifth quintile, 57.5%–114.3% of people.

  • **** Income quintile has variable cut-off values in each city or Census area to take cost of living into account. A DA being in quintile 1 means it is among the lowest 20% of DAs in its city by income.

  • †††† First quintile represents 0%–4.1% of people aged 25–64 years without a diploma; second quintile, 4.1%–7.5% of people; third quintile, 7.5%–11.4% of people; fourth quintile, 11.4%–17.1% of people; and fifth quintile, 17.1%–94.3% of people.

  • ‡‡‡‡ First quintile represents 0%–2.2% of people in the area who self-identified as a visible minority; second quintile, 2.2%–7.5% of people; third quintile: 7.5%–18.7% of people; fourth quintile, 18.7%–43.5% of people; and fifth quintile, 43.5%–100% of people.

  • §§§§ First category represents 0%–2.1% of people in a DA being recent immigrants; second category, 2.1%–4.7% of people; and third category, 4.7%–41.2% of people.