$truncation character (wildcard)
exp“explodes” controlled vocabulary term(e.g., expands search to all more specific related termsin the vocabulary’s hierarchy)
.de.limit controlled vocabulary heading
.fs.floating subheading
.hw.limit to heading word
.md.type of methodology (PsycINFO)
.mp.combined search fields (default if no fields are specified)
.pt.publication type
.ti.limit to title
.tw.limit to title and abstract fields

From: Appendix B, Methods of Identifying the Literature

Cover of Comparative Effectiveness of Core-Needle and Open Surgical Biopsy for the Diagnosis of Breast Lesions
Comparative Effectiveness of Core-Needle and Open Surgical Biopsy for the Diagnosis of Breast Lesions [Internet].
Comparative Effectiveness Reviews, No. 19.
Bruening W, Schoelles K, Treadwell J, et al.

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