Strang 2021.

Study characteristics
Methods	Study design: retrospective cohort study Type of publication: journal publication Setting and dates: Strang 2020: hospitals and nursing homes, 1 March 2020 to 24 April 2020 Strang 2021: hospitals and nursing homes, data retrieved 24 August 2020 Country: Sweden Language: English Inclusion/exclusion criteria: nursing home residents who died with a COVID‐19 diagnosis and an expected death based on their disease trajectory either in the nursing home or in hospital registered in the Swedish Register of Palliative Care
Participants	Age: Strang 2020: mean age (range): 84.7 (47 to 104) Strang 2021: mean age (range): 86.7 (57 to 107) in nursing homes, 83.3 (30 to 107) in hospitals Gender:  Strang 2020: 189 women/201 men Strang 2021: 947 women/1158 men Ethnicity: NR Number of participants (recruited/allocated/evaluated): Strang 2020: all deaths in hospitals or nursing homes (n = 490) were analyzed. Deaths in other settings (specialized palliative care wards (n = 11), in palliative homecare (n = 2), or in their own homes (n = 8)) were excluded (n = 21). Only patients with expected deaths (n = 390) were entered in the final analysis. Participants are a partial subset of those reported in Strang 2021.  Strang 2021: 2105 (1903 nursing home deaths and 202 nursing home residents who were admitted to hospital before death) Symptoms at baseline:  Strang 2020: breathlessness (173), anxiety (197), delirium (77), death rattles (178), and pain (210) Strang 2021: breathlessness (665), anxiety (1117), delirium (486), and respiratory secretions (1053) Comorbidities: NR
Interventions	Pharmacological intervention(s): Strang 2020: strong opioid (376), tranquilizer (376), antiemetic (357), anticholinergic (370) Strang 2021: for all participants (n = 2105), corrected for missing answers: as‐needed prescription (during the last week of life) of strong opioids: 2019 of 2095 participants (96%); as‐needed prescription (during the last week of life) of tranquillizers: 2014 of 2094 participants (96%); as‐needed prescription (during the last week of life) of antiemetics: 1915 of 2082 participants (92%); as‐needed prescription (during the last week of life) of anticholinergics: 2000 of 2093 participants (95%). Non‐pharmacological intervention(s): none
Outcomes	Primary review outcomes Symptom relief, retrospectively assessed through the end‐of‐life questionnaire (ELQ) Secondary review outcomes None reported Additional outcomes reported Human presence at death
Notes	Participant data for the 2 cohorts were extracted from the same database, resulting in overlap between cohorts. We do not know how many participants are reported on twice.  Sponsor/funding: supported by Region Stockholm (ALF) and the Stockholm Sjukhem Foundation’s Jubilee Fund. COI: no competing financial interests exist.
Risk of bias
Bias	Authors' judgement	Support for judgement
Selection bias (unrepresentative study group) All outcomes	Low risk	Clear inclusion criteria
Attrition bias (incomplete outcome assessment/follow up) All outcomes	Low risk	Only assessed when participant was dead
Detection bias (outcome detectors blinded to intervention) All outcomes	High risk	Not blinded
Confounding (important prognostic factors or follow‐up not taken adequately into account) All outcomes	High risk	Not controlled for confounders
Reporting bias (poorly defined study group) All outcomes	Low risk	Study group well defined.
Reporting bias (poorly defined follow up) All outcomes	Low risk	Assessed until death
Reporting bias (poorly defined outcome) All outcomes	Low risk	Validated questionnaire (ELQ) used.

CSCI: continuous subcutaneous infusion

m‐RASS: modified Richmond Agitation‐Sedation Scale

COI: Conflict of Interest

IQR: Interquatile Range

NR: Not reported