Table 1 Search strategy in Web of Science and PubMed

Broad search query

((diesel) and (exhaust or particulate matter or microparticles or emissions or exposure))

AND

(cancer or carcino* or neoplasm or tumo*))

(((diesel) and (exhaust or particulate matter or microparticles or emissions or exposure))

AND

(cancer or carcinogen* or carcinoma or carcinomas or carcinomous or carcinoid or carcinoids or neoplasm or tumor or tumour or tumorous or tumors or tumours))

AND (Humans[Mesh])

Specific search query (restricted to bladder cancer)

((diesel) and (exhaust or particulate matter or microparticles or emissions or exposure))

AND

(cancer or carcino* or neoplasm or tumo*)) AND(bladder or urinary or transitional)

(((diesel) and (exhaust or particulate matter or microparticles or emissions or exposure))

AND

(cancer or carcinogen* or carcinoma or carcinomas or carcinomous or carcinoid or carcinoids or neoplasm or tumor or tumour or tumorous or tumors or tumours))

AND (Humans[Mesh])

AND (bladder or urinary or transitional)

Search fields

‘Topic’

(abstract, title, author keywords, KeyWords Plus)

‘All fields’ (including abstract, title, author keywords, MeSH terms)

Database-specific keywords

KeyWords Plus, added by Clarivate Analytics based on each article’s reference list [12]

MeSH terms, suggested by an algorithm based on the full-text of each article and manually checked by professional indexers from the U.S. National Library of Medicine [13]

Search date

16 September 2018

16 September 2018