Is there excess mortality in women screened with mammography: a meta-analysis of non-breast cancer mortality

Table 2 Bias assessment of included studies

Clinical trial	Randomization	Classification of the cause	Post-randomization	Contamination bias	Compliance bias study
		of death	exclusions	control group	group
UK Age Trial [17, 18]	Low risk of bias	Low risk of bias	Low risk of bias	No risk of bias	No risk of bias
Goteborg [7, 8, 19, 20]	High risk of bias	Low risk of bias	Low risk of bias	No risk of bias	No risk of bias
Malmö 1 [8, 21]	Low risk of bias	Unclear risk of bias	Low risk of bias	Low risk of bias	+
Malmö 2 [7, 22]	High risk of bias	Low risk of bias	Unclear risk of bias	No risk of bias	No risk of bias
Stockholm [8, 23]	High risk of bias	Unclear risk of bias	Unclear risk of bias	No risk of bias	No risk of bias
Canada 1 [24, 27]	Low risk of bias	Low risk of bias	Low risk of bias	+	No risk of bias
Canada 2 [25, 26]	Low risk of bias	Low risk of bias	Low risk of bias	+	No risk of bias
2 Swedish counties [28–30]	High risk of bias	High risk of bias	High risk of bias	No risk of bias	No risk of bias
New York [31–33]	High risk of bias	Low risk of bias	Unclear risk of bias	Low risk of bias	+
Edinburgh [34]	High risk of bias	Low risk of bias	High risk of bias	No risk of bias	+

ISSN: 1745-6215