PubMed:
Provider: NLM
Database: PubMed (National Library of Medicine), https://pubmed.ncbi.nlm.nih.gov
Date(s) Searched: October 28, 2026
Date range searched: 2020-present
Language: English
Publication types excluded: Comment, Case Reports, Editorial, Preprint
Final count: 349 (line 19)
Search Terms:

No. | Query | Results
1 | "COVID-19"[Majr] OR "Post-Acute COVID-19 Syndrome"[Majr] OR "SARS-CoV-2"[Majr] OR "pediatric multisystem inflammatory disease, COVID-19 related"[Supplementary Concept] | 268,269
2 | "COVID-19"[ti] OR COVID19[ti] OR "SARS-CoV-2"[ti] OR "SARS-CoV2"[ti] OR "coronavirus disease 2019"[ti] OR "2019-nCoV"[ti] OR "novel coronavirus"[ti] OR "long COVID"[ti] OR "post-COVID"[ti] OR "post-acute sequelae"[ti] OR PASC[ti] OR "long hauler*"[ti] OR "MIS-C"[ti] OR "PIMS-TS"[ti] | 390,290
3 | "multisystem inflammatory syndrome"[tw] OR "paediatric inflammatory multisystem syndrome"[tw] OR "pediatric inflammatory multisystem syndrome"[tw] | 3,339
4 | "COVID-19"[ot] OR "SARS-CoV-2"[ot] OR "long COVID"[ot] OR "post-acute sequelae"[ot] | 261,294
5 | 1 OR 2 OR 3 OR 4 | 461,956
6 | "Cognition"[Majr:NoExp] OR "Cognitive Dysfunction"[Mesh] OR "Neurocognitive Disorders"[Majr:NoExp] OR "Memory Disorders"[Mesh] OR "Memory"[Majr:NoExp] OR "Memory, Episodic"[Mesh] OR "Memory, Short-Term"[Mesh] OR "Executive Function"[Mesh] OR "Attention"[Majr:NoExp] OR "Mental Fatigue"[Mesh] OR "Neurologic Manifestations"[Majr:NoExp] OR "Neuropsychological Tests"[Mesh] | 457,134
7 | cognition[ti] OR cognitive[ti] OR neurocognition[ti] OR neuropsychological[ti] | 216,454
8 | neurocognitive[tiab] OR "cognitive impairment"[tiab] OR "cognitive dysfunction"[tiab] OR "cognitive decline"[tiab] OR "cognitive deficit*"[tiab] OR "cognitive function*"[tiab] OR "cognitive performance"[tiab] OR "cognitive symptom*"[tiab] OR "brain fog"[tiab] OR "memory impairment"[tiab] OR "memory loss"[tiab] OR "memory complaint*"[tiab] OR "memory problem*"[tiab] OR "working memory"[tiab] OR "episodic memory"[tiab] OR "executive function*"[tiab] OR "executive dysfunction"[tiab] OR "sustained attention"[tiab] OR "attention span"[tiab] OR "difficulty concentrating"[tiab] OR "concentration difficulties"[tiab] OR "processing speed"[tiab] OR "neurological symptom*"[tiab] OR "neurologic symptom*"[tiab] OR "neurological manifestation*"[tiab] OR "neurologic manifestation*"[tiab] OR "neurological sequelae"[tiab] OR "neurologic sequelae"[tiab] OR "Neuro-PASC"[tiab] OR "neuropsychiatric symptom*"[tiab] | 452,535
9 | cognition[ot] | 46,017
10 | 6 OR 7 OR 8 OR 9 | 793,570
11 | "COVID-19 Vaccines"[Majr] OR "Vaccination"[Majr] OR "Breakthrough Infections"[Majr] OR "COVID-19 breakthrough infections"[Supplementary Concept] | 74,035
12 | vaccin*[ti] OR unvaccinated[ti] OR immuniz*[ti] OR immunis*[ti] OR "booster dose*"[ti] OR BNT162b2[ti] OR "mRNA-1273"[ti] OR ChAdOx1[ti] | 301,694
13 | "breakthrough infection*"[tiab] OR "vaccination status"[tiab] | 11,914
14 | vaccin*[ot] | 129,982
15 | 11 OR 12 OR 13 OR 14 | 344,365
16 | 5 AND 10 AND 15 | 460
17 | "Comment"[Publication Type] OR "Case Reports"[Publication Type] OR "Editorial"[Publication Type] OR "Preprint"[Publication Type] | 4,270,113
18 | 16 NOT 17 | 351
19 | 18 AND english[la] AND 2020:3000[dp] | 349

Final query as run through NCBI E-utilities (line 19):
(((("COVID-19"[Majr] OR "Post-Acute COVID-19 Syndrome"[Majr] OR "SARS-CoV-2"[Majr] OR "pediatric multisystem inflammatory disease, COVID-19 related"[Supplementary Concept]) OR ("COVID-19"[ti] OR COVID19[ti] OR "SARS-CoV-2"[ti] OR "SARS-CoV2"[ti] OR "coronavirus disease 2019"[ti] OR "2019-nCoV"[ti] OR "novel coronavirus"[ti] OR "long COVID"[ti] OR "post-COVID"[ti] OR "post-acute sequelae"[ti] OR PASC[ti] OR "long hauler*"[ti] OR "MIS-C"[ti] OR "PIMS-TS"[ti]) OR ("multisystem inflammatory syndrome"[tw] OR "paediatric inflammatory multisystem syndrome"[tw] OR "pediatric inflammatory multisystem syndrome"[tw]) OR ("COVID-19"[ot] OR "SARS-CoV-2"[ot] OR "long COVID"[ot] OR "post-acute sequelae"[ot])) AND (("Cognition"[Majr:NoExp] OR "Cognitive Dysfunction"[Mesh] OR "Neurocognitive Disorders"[Majr:NoExp] OR "Memory Disorders"[Mesh] OR "Memory"[Majr:NoExp] OR "Memory, Episodic"[Mesh] OR "Memory, Short-Term"[Mesh] OR "Executive Function"[Mesh] OR "Attention"[Majr:NoExp] OR "Mental Fatigue"[Mesh] OR "Neurologic Manifestations"[Majr:NoExp] OR "Neuropsychological Tests"[Mesh]) OR (cognition[ti] OR cognitive[ti] OR neurocognition[ti] OR neuropsychological[ti]) OR (neurocognitive[tiab] OR "cognitive impairment"[tiab] OR "cognitive dysfunction"[tiab] OR "cognitive decline"[tiab] OR "cognitive deficit*"[tiab] OR "cognitive function*"[tiab] OR "cognitive performance"[tiab] OR "cognitive symptom*"[tiab] OR "brain fog"[tiab] OR "memory impairment"[tiab] OR "memory loss"[tiab] OR "memory complaint*"[tiab] OR "memory problem*"[tiab] OR "working memory"[tiab] OR "episodic memory"[tiab] OR "executive function*"[tiab] OR "executive dysfunction"[tiab] OR "sustained attention"[tiab] OR "attention span"[tiab] OR "difficulty concentrating"[tiab] OR "concentration difficulties"[tiab] OR "processing speed"[tiab] OR "neurological symptom*"[tiab] OR "neurologic symptom*"[tiab] OR "neurological manifestation*"[tiab] OR "neurologic manifestation*"[tiab] OR "neurological sequelae"[tiab] OR "neurologic sequelae"[tiab] OR "Neuro-PASC"[tiab] OR "neuropsychiatric symptom*"[tiab]) OR (cognition[ot])) AND (("COVID-19 Vaccines"[Majr] OR "Vaccination"[Majr] OR "Breakthrough Infections"[Majr] OR "COVID-19 breakthrough infections"[Supplementary Concept]) OR (vaccin*[ti] OR unvaccinated[ti] OR immuniz*[ti] OR immunis*[ti] OR "booster dose*"[ti] OR BNT162b2[ti] OR "mRNA-1273"[ti] OR ChAdOx1[ti]) OR ("breakthrough infection*"[tiab] OR "vaccination status"[tiab]) OR (vaccin*[ot]))) NOT ("Comment"[Publication Type] OR "Case Reports"[Publication Type] OR "Editorial"[Publication Type] OR "Preprint"[Publication Type])) AND english[la] AND 2020:3000[dp]

AI-use statement:
The PubMed search strategy was drafted with the PICO search builder. It used the large language model claude-opus-5-5 (Anthropic; accessed October 28, 2026) to propose search concepts and terms from the review question. The tool made 1 call to the model at high effort (the draft); claude-opus-5-5 was requested and answered it. A refusal fallback was enabled (had the model declined a request, the API could have run it again on another model Anthropic recommends); it was not used. Every MeSH heading, Supplementary Concept and publication type the strategy searches was checked against NLM MeSH (id.nlm.nih.gov) before use: 24 valid. Each numbered line was run in PubMed through NCBI E-utilities on October 28, 2026, and PubMed's own diagnostics (phrases not found, ignored words, lost truncation) were checked. The strategy was tested against 6 known relevant studies that were not shown to the model: 4 were retrieved (95% CI 22%–96%). Retrieving known studies does not prove the search is complete. 3 further known studies were shown to the model as examples. Compared with the reference strategy, the strategy retrieves 134 of the reference's 521 records (relative recall 26%). Relative recall counts every record the reference retrieves, relevant or not, so it does not show how many relevant studies the strategy finds. The reference strategy's header gives 2020 to present, which none of its lines applies; it was run without it. A searcher must review the strategy before it is used. The prompts, the model output and every version are in the provenance file (JSON export).

Review question: What is the association between COVID-19 vaccination and neurocognitive outcomes of COVID-19, including long COVID and multisystem inflammatory syndrome in children?
Run c9bb2804-c4f8-471f-9516-06d45afa005b, exported October 29, 2026 from the PICO search builder.