Table 2.

Search strategy

Item	Search term	Boolean operator
Tremor	(‘tremor*’[All Fields] OR ‘tremor*’ [MeSH Terms], ‘shaking’ [All Fields] OR ‘shaking’ [MeSH Terms])	AND
Lesion	(‘lesion*[All Fields] OR ‘lesion*’ [MeSH Terms], ‘thalamotomy’ [All Fields] OR ‘thalamotomy’ [MeSH Terms], ‘subthalamotomy’ [All Fields] OR ‘subthalamotomy’ [MeSH Terms], ‘pallidotomy’ [All Fields] OR ‘pallidotomy’ [MeSH Terms],	AND
Neurosurgery	(‘neurosurg*’[All Fields] OR ‘neurosurg*’ [MeSH Terms])	AND
Time period	Between 1 January 1990 and 1 February 2017