Importance: Nursing home residents have been disproportionately impacted by the COVID-19 epidemic. Prevention recommendations have emphasized frequent testing of healthcare personnel and residents, but additional strategies are needed to protect nursing home residents. Objective: We developed a reproducible index of nursing home crowding and determined whether crowding was associated with incidence of COVID-19 in the first months of the COVID-19 epidemic. Design, Setting, and Participants: Population-based retrospective cohort study of over 78,000 residents of 618 distinct nursing homes in Ontario, Canada from March 29 to May 20, 2020. Exposure: The nursing home crowding index equalled the average number of residents per bedroom and bathroom. Outcomes: Primary outcomes included the cumulative incidence of COVID-19 infection and mortality, per 100 residents; introduction of COVID-19 into a home (>=1 resident case) was a negative tracer. Results: Of 623 homes in Ontario, we obtained complete information on 618 homes (99%) housing 78,607 residents. A total of 5,218 residents (6.6%) developed COVID-19 infection, and 1,452 (1.8%) died with COVID-19 infection as of May 20, 2020. COVID-19 infection was distributed unevenly across nursing homes: 4,496 (86%) of infections occurred in just 63 (10%) of homes. The crowding index ranged across homes from 1.3 (mainly single-occupancy rooms) to 4.0 (exclusively quadruple occupancy rooms); 308 (50%) homes had high crowding index (>=2). Incidence in high crowding index homes was 9.7%, versus 4.5% in low crowding index homes (p<0.001), while COVID-19 mortality was 2.7%, versus 1.3%. The likelihood of COVID-19 introduction did not differ (31.3% vs 30.2%, p=0.79). After adjustment for regional, nursing home, and resident covariates, the crowding index remained associated with increased risk of infection (RR=1.72, 95% Confidence Interval [CI]: 1.11-2.65) and mortality (RR=1.72, 95%CI: 1.03-2.86). Propensity score analysis yielded similar conclusions for infection (RR=2.06, 95%CI: 1.34-3.17) and mortality (RR=2.09, 95%CI: 1.30-3.38). Simulations suggested that converting all 4-bed rooms to 2-bed rooms would have averted 988 (18.9%) infections of COVID-19 and 271 (18.7%) deaths. Conclusions and Relevance: Crowding was associated with higher incidence of COVID-19 infection and mortality. Reducing crowding in nursing homes could prevent future COVID-19 mortality.

IntroductionOntario ambulances are restricted from patient transportation to sub-acute levels of care when these facilities may be more suitable than emergency departments for non-emergent conditions. There is no known patient classification specifically constructed to inform ED diversion protocols and guidance for sub-acute centre transportation for primary care–like patient conditions.ObjectiveTo construct a novel patient classification of potentially preventable emergency department visits following transport by ambulance, and analyse patient-level characteristic associations with this classification based in Ontario secondary data.Methods and analysisThe Primary Care–like Ambulance transports following Response for 911-Emergencies (PriCARE) patient classification will be constructed using a two-phase RAND/UCLA modified Delphi design. All experts included are physicians with relevant experience in emergency and/or primary care in Ontario. The first phase of the study will determine consensus of the expert committee on which ED interventions performed on patients with non-emergent acuities could be conducted in sub-acute healthcare centres. The second phase will assess consensus of which patient, hospital and acuity factors are most appropriate to be incorporated into a PriCARE classification. We will also investigate secondary outcomes on consensus of which ED interventions could be transferred to a paramedic context given an expanded scope of practice and patient-level characteristics of PriCARE classified individuals.Ethics and disseminationThis study received a research ethics board exemption waiver from the Hamilton Integrated Research Ethics Board; review reference 2020-11451-GRA. Results will be submitted for publication in a peer-reviewed journal and presented at relevant conferences. The results will be shared with Ontario paramedic services and governing institutions. This study will be used to inform patient classification protocols and clinical decision tools for ambulances to transport to sub-acute healthcare centres.Trial registration numberISRCTN22901977.

BACKGROUND Home‐based primary care has been associated with reductions in hospital use among homebound older adults, but population‐based studies on the general home visit patterns of primary care physicians are lacking. OBJECTIVE We examined the association between the provision of home visits by primary care physicians and subsequent use of hospital‐based care among their older adult patients with extensive functional impairments. DESIGN Population‐based retrospective cohort study. SETTING The setting was Ontario, Canada, from October 2014 to September 2016. PARTICIPANTS Older adults (aged ≥65 years) with extensive functional impairments receiving publicly funded home care. MEASUREMENTS We measured the provision of home visits by a patientʼs most responsible primary care physician during the year before a comprehensive home care assessment. Physician home visit patterns were measured as the proportion of the total outpatient visits in a year that were home visits, categorized with quartiles. Multivariable, multilevel negative binomial regression models examined the associations between physician‐level home visit provision and patient emergency department visits and hospital admissions over the 6 months following the home care assessment. RESULTS There were 49,613 patients in the cohort who were linked to 8,096 unique primary care physicians. A total of 69.1% of physicians provided at least one home visit in a year, with the median proportion of home visits to total visits ranging from 0.057% to 3.19% across quartiles. Patients whose physicians were in the highest home visit provision quartile had lower rates of emergency department visits (incidence rate ratio [IRR] = 0.93; 95% confidence interval [CI] = 0.90–0.96) and hospital admissions (IRR = 0.89; 95% CI = 0.85–0.93) compared with patients whose physician did not do home visits. CONCLUSION Home care patients with extensive functional impairments whose physicians provided higher levels of home visits had fewer emergency department visits and hospital admissions. Expanding home visits by primary care physicians could reduce hospital use by older adults living with functional impairments in the community.