Per-lot COVID adverse-event rate distributions

Each row shows how an adverse event’s reporting rate varies from lot to lot. The crude box (blue) is the raw per-lot rate; the age-adjusted box (orange) standardizes for each lot’s recipient-age mix. Age adjustment narrows much of the spread, indicating that a substantial share of the lot-to-lot variation is associated with the age of the recipients. A residual spread remains that this adjustment does not account for.

Crude per-lot rate Age-adjusted box = IQR, line = median, whiskers = 1.5×IQR

Totals

By adverse-event category

Individual adverse events (MedDRA terms)

The most-reported individual terms plus the clinically serious ones. For rarer events many lots report zero, so medians sit near the floor and the boxes are wide — expected for low per-lot counts.

Adverse event	Crude median /mil	Crude IQR	Age-adj median	Age-adj IQR	IQR shrink
Arthralgia	21.08	9.08–56.44	30.35	19.41–38.88	2.4×
Dizziness	20.33	5.80–48.68	25.06	13.82–34.48	2.1×
Chills	17.54	6.17–58.42	24.92	14.65–40.63	2.0×
Asthenia	14.93	7.32–40.14	20.99	14.47–26.26	2.8×
Fatigue	7.65	2.93–28.59	12.27	6.64–20.05	1.9×
Headache	6.62	2.07–20.66	9.98	5.07–15.90	1.7×
Erythema	5.78	2.11–14.76	7.23	4.44–12.55	1.6×
Chest pain	5.75	1.75–9.95	5.83	3.52–8.20	1.8×
Extra dose administered	5.44	2.90–9.99	7.55	2.19–14.47	0.6×
Chest discomfort	5.37	1.46–10.63	6.07	3.29–8.57	1.7×
Abdominal pain	5.11	1.84–10.71	6.12	3.95–8.35	2.0×
Rash	4.84	1.47–11.66	6.11	3.15–8.21	2.0×
Cough	4.61	1.65–9.74	5.64	3.39–7.74	1.9×
Anxiety	4.57	1.26–12.39	5.81	2.70–8.30	2.0×
Dyspnoea	4.46	1.29–10.23	5.45	2.68–7.54	1.8×
Back pain	4.40	1.57–10.69	5.91	3.15–7.86	1.9×
Injection site erythema	4.19	1.49–12.18	5.08	2.52–14.07	0.9×
Condition aggravated	4.16	1.57–7.67	4.51	2.63–6.33	1.6×
Pruritus	4.01	1.02–9.90	4.93	2.44–7.35	1.8×
Abdominal pain upper	3.94	1.09–9.42	4.96	2.20–7.01	1.7×
Acute respiratory failure	3.91	1.48–7.38	4.60	2.08–8.26	1.0×
Hypoaesthesia	3.66	0.78–8.52	4.22	1.82–6.44	1.7×
Ageusia	3.00	0.83–8.66	4.04	1.71–6.08	1.8×
Abdominal discomfort	2.95	1.05–8.91	4.41	1.96–6.40	1.8×
Injection site pain	2.82	1.01–7.26	3.86	2.14–5.95	1.6×
Pain in extremity	2.80	0.73–9.10	4.37	1.52–6.73	1.6×
Blood pressure increased	2.37	0.68–6.30	2.95	1.13–4.86	1.5×
Diarrhoea	2.34	0.67–7.66	3.41	1.26–5.94	1.5×
Body temperature	2.26	0.26–8.74	3.78	0.75–6.82	1.4×
Death	1.88	0.33–5.81	2.89	0.82–5.27	1.2×
Bell's palsy	1.39	0.00–4.59	1.88	0.00–3.19	1.4×
Anaphylactic reaction	0.91	0.00–2.47	1.15	0.00–2.13	1.2×
Cerebrovascular accident	0.75	0.00–2.42	0.99	0.00–1.96	1.2×
Deep vein thrombosis	0.56	0.00–1.52	0.49	0.00–1.30	1.2×
Myocarditis	0.00	0.00–0.00	0.00	0.00–0.00	—
Pericarditis	0.00	0.00–0.00	0.00	0.00–0.00	—
Guillain-Barre syndrome	0.00	0.00–0.00	0.00	0.00–0.00	—
Pulmonary embolism	0.00	0.00–0.30	0.00	0.00–0.24	1.2×
Thrombocytopenia	0.00	0.00–0.00	0.00	0.00–0.00	—
Seizure	0.00	0.00–1.02	0.00	0.00–0.99	1.0×
Myocardial infarction	0.00	0.00–0.00	0.00	0.00–0.00	—
Cardiac arrest	0.00	0.00–0.78	0.00	0.00–0.57	1.4×

Read carefully. Per-lot rates use the 552 lots with known dose denominators only (imputed per-lot doses are unreliable). Passive VAERS reporting rates — not incidence, not causal. Age adjustment is indirect standardization on the age mix of reporters only; it cannot adjust for comorbidity, care setting, or era-specific reporting intensity, so a residual spread remains. A wide crude box reflects a range of factors — differing recipient populations among them (see the rollout page) — and is not by itself an indication that a lot is unsafe or that it is safe.

Data: VAERS 2006–2024 lot cases × openVAERS doses. Reproducible: compute_ae_boxplots.py + build_ae_boxplot_page.py. Passive surveillance; hypothesis-generating only.