Table 1. US (table summarises published studies on US in screening, including study design, quality features, and results).

Reference	Objectivea; comparator	Population (mean age in years)	Test evaluated 1 – In consecutive screenees 2 – Independent of comparator	No. of breast cancers (total sample size)	TPR or sensitivity	FPR (based on solid lesions for US)
Kolb et al (1998, 2002)	I only; M+CBE Views: ND Reader: 1–2	Dense breasts and normal M+CBE (54.7)	1–Yes 2–ND for all subjects (Yes for M-negative/US-positive group)	145; 124b (13 547 screens in 5418 women)	Incremental TPR of US=25.5%	Incremental FPR of US=2.4% (biopsy) and 5.3% (biopsy or follow-up)
Hou et al (2002)	I+R; M+CBE Views: 2 Reader: 1	‘High-risk’ female relatives of breast cancer patients (48.6)	1–ND 2–ND	21 (935)	US: 90.4% M: 52.4% CBE: 33.3% Incremental TPR of US=33.3%	For abnormal screen – biopsy US: 12.9–2.5% M: 6.0–1.6% CBE: 1.8–1.2% Incremental FPR of US=6.9%
O'Driscol et al (2001)	I + R; M Views and Reader: ND	Moderate-risk (family history) through clinical genetics unit (42)	1–Yes 2–Yes	2b (150)	US: 50% M: 50%	US: 6.0% M: 0.7% (core biopsy rate)
Warner et al (2001)	I+R; M+CBE Views: 2 Reader: 1	High-risk, BRCA mutation or several family members (43)	1–ND 2–YES	6; 5b (186)	US: 60% M: 40% CBE: 20% Incremental TPR of US=0%	US: 7% M: 1% CBE: 1%
Buchberger et al (1999)	I+R; M Reader: 1	Dense breasts and normal CBE (49)	1–ND 2–ND	182; 130b (8970)	US: 99% (invasive), 46% (DCIS) M: 73% (invasive), 90% (DCIS)	US: 4% (biopsy) M: ND

US=ultrasound; M=mammography; CBE=clinical breast examination; ND=not described or unclear from paper; TPR=true-positive rate; FPR=false-positive rate. DCIS=ductal carcinoma in situ.

^aObjective attainable in using the test: R=replacement for comparator, I=incremental to comparator; Views=number of mammography views per breast, Reader=number of mammography readers.

^bNumber of cancers reported to be invasive cancers.