Table 2.

Variables Considered in Model.

Variable	Time-Dependency	Completeness	Notes
Age	Independent	100%	Age at time of enrollment
Sex	Independent	100%
Smoking history	Independent	99.7%	Never vs current/former
Ethnicity	Independent	85%
Cancer stage	Independent	95%	At time of enrollment
Histology	Independent	99.7%	SCLC and NSCLC sub-histologies
Time after full vaccination	Dependent	100%	The time interval after the patient received a full vaccination
Variable Event		Percent (N)
Steroid use	Dependent; 30 Days	32.4%	Systemic steroids such as prednisone, methylprednisolone, dexamethasone, hydrocortisone, or other, used long-term (>7 days).
Chemotherapy	Dependent; 30 Days	64.5%	Taxanes, platinum, pemetrexed, gemcitabine, vinorelbine, or other
Targeted Therapy	Dependent; 30 Days	18.6%	Osimertinib, erlotinib, gefitinib, afatinib, dacomitinib, bevacizumab, ramucirumab, crizotinib, alectinib, brigatinib, ceritinib, lorlatinib, entrectinib, selpercatinib, capmatinib, pralsetinib, larotrectinib, cabozantinib, vandetanib, tepotinib, or other
Immune therapy	Dependent; 30 Days	64.5%	Pembrolizumab, nivolumab, atezolizumab, durvalumab, cemiplimab, ipilimumab, or other
SARS-CoV-2 Booster	Dependent; 90 Days	77%	See Supplementary Table S3
Influenza vaccination	Dependent; 90 Days	100%	Unless administered concurrently with SARS-CoV-2 booster
SARS-CoV-2 infection	Dependent; prior to reading	51.7%	Includes any report of a positive test or anti-N plasma values above the 2000 unit threshold prior to the titer measurement.

“Completeness” indicates the completeness of data for variables that apply to all patients. “Days” indicates the amount of time prior to a blood reading in which the event was considered. Variable Events indicates an optional intervention or a SARS-CoV-2 infection.