Search results
The search of this overview retrieved 826 records, we excluded 191 articles after removing duplicates and screening title or abstract. The remaining 54 records, 9 were excluded due to the lack of target outcomes of this overview, 11 were excluded due to no meta-analysis conducted, 12 were excluded due to not focus on BC screening. Ultimately, 22 studies were included in this overview [2, 13-33]. Details of the PRISMA flow chart of literature studies for this overview are presented in Fig. 1.
Characteristics of included SRs
The details characteristics of the included 22 SRs with meta-analysis included primary studies ranging from 4 to 24 are presented in Table 1 . 19 from developed countries, 3 from developing countries, 17 SRs reported database searched, only 1 study retrieved Chinese databases. 11 assessed the methodological quality, 9 SRs used QUADAS-2, 1 SRs used QUADAS, 1 used quality score evaluation system for assessing the quality of RCTs published by Chalmers et al.
Results of methodological quality
ROBIS tool was evaluation was conducted in the 22 SRs. The assessment results of each item in phase 2 of the ROBIS tool are all presented in Table 2, A total of 15 SRs (68.2%) were assessed as having high RoBs on the domain 1. Domain 2 had 77.3% (17 SRs) of judgments as high RoBs. A total of 8 SRs (36.4 %) were assessed to be at high RoBs on domain 3. Domain 4 had 59.1% (13 SRs) of judgments as high RoBs. The final phase considered the overall RoBs, 19 SRs (86.4%) were assessed to be high RoBs. The details of ROBIS assessment results are mapped in fig.2 and fig.3.
Association between mammography screening and breast cancer mortality
Nine SRs were identified comparing the association of mammography vs. no screening on BC mortality. Pooled estimates for a reduction in BC mortality attributable to mammography screening stratified by study design were range from 0.51 (OR, 95% CI: 0.46-0.55) to 1.04 (RR, 95% CI: 0.84-1.27). An SRs of 10 case-control studies average a 49% reduction in BC mortality for women who are screened (0.51 [OR, 95% CI: 0.46-0.55]), which was similar to SRs with quasi-RCTs conducted by Gøtzsche et al. (0.75 [RR, 95% CI: 0.67-0.83]), Hendrick et al. (0.71 [RR, 95% CI: 0.57-0.89] and Cochrane analysis (0.71 [RR, 95% CI: 0.61-0.83]) [26, 27, 32]. Pooled estimates of SRs with RCTs only conducted by Magnus (0.83 [RR, 95% CI: 0.72-0.97]), Gøtzschewere et al. (1.04 [RR, 95% CI: 0.84-1.27]), and Cochrane analysis (0.93 [RR, 95% CI: 0.79-1.09]) generally higher (mortality reduction lower) than with those observed with the other study design trials (Table 2) [25, 26, 32].
In the SRs of RCTs that stratified by age, a significantly reduces BC mortality among women with the latest follow-up data (aged 40-49) invited to screening mammography was observed by Hendrick et al. (0.82[RR, 95% CI: 0.71-0.95], 7 RCTs) and Magnus et al. (0.83 [RR, 95% CI: 0.72-0.97)], 8 RCTs) [25, 27]; however, pooled estimates are not statistically significant for SRs conducted by Nelson et al. (0.92, [RR, 95% CI: 0.75-1.02], 9 trials), and Smart et al. (0.84 [RR, 95% CI: 0.69-1.02], 8 RCTs) [2, 33]. The Cochrane analysis with adequately randomized trials found no significant BC mortality reduction among women below 50 years for follow up after 7 years (0.94 [RR, 95% CI: 0.78-1.14]) and 13 years (0.87 [RR, 95% CI: 0.73-1.03]). The Cochrane analysis reported that the pooled estimates for mortality reduction in screening women aged 50 years or older was lower when combined sub-optimally randomized trials with 7 and 13 years follow up (0.88 [RR, 95% CI: 0.64-1.20] and 0.94 [RR, 95% CI: 0.77-1.15]) than adequately randomized trials with 7 and 13 years (0.67 [RR, 95% CI: 0.56-0.81] and 0.70 [RR, 95% CI: 0.62-0.80]) [32]. An SRs conducted by Nelson et al. observed a statistically significant among women aged 50 to 59 (0.86 [RR, 95% CI: 0.68-0.97]) and aged 60 to 69 years (0.67 [RR, 95% CI: 0.54-0.83]), the combined RR is not statistically significant for women aged 70-74 (P>0.05) [2].
Performance of mammography screening technology
Eight SRs reported the accuracy of BC screening conducted using mammography (Table 3). Sensitivity of difference mammography was ranged from 55% to 90.77%, specificity of difference mammography was ranged from 84%-97%. The sensitivity of DBT + FFDM, CESM, DM, FM, and FFDM, were 90.77%(95% CI: 80.7%-96.51%), 89%(95% CI: 88%-91%), 76%(95% CI: 70%-81%), 76% (95% CI: 70%-81%), and 60.00% (95% CI , 47.10%-71.96%), respectively. The specificity of FM, DBT + FFDM, DM, FFDM, and CESM were 97% (95% CI: 94%-98%), 96.49% (95% CI: 96.04%-96.90%), 96% (95% CI: 94%-97%), 95.55% (95% CI: 95.04%-96.01%), and 84% (95% CI: 82%-85%). The DOR of BC screening conducted using the CESM, DM, SFM were 71.36(95% CI: 36.28-140.39), 72(95% CI: 44-118), and 91(95% CI: 52-157).
Seven SRs compared the performance of difference mammography (Table 4). The pooled estimates for CDR of DBT vs. DM, DBT + SM vs. DM, and DBT + FFDM vs. FFDM were 0.0016 (RD, 95% CI: 0.0011-0.002), 1.38(RR, 95% CI:1.24-1.54), and 1.29 (RR, 95% CI: 1.164-1.429). The CDR of FM was similar to FFDM (0.93[RR, 95% CI: 0.83-1.03]), two studies evaluated the CDR of DBT + DM and DM and statistically significant were both observed (1.36 [RR, 95% CI: 1.18-1.58] and 1.52 [RR, 95% CI: 1.08-2.12]). Moreover, the pooled estimates for CDR of DM vs. FM in two SRs found a statistically significant (1.17 [RR, 95% CI: 1.06-1.29] and 0.00051 [RD, 95% CI: 0.00019-0.00083]). The risk ratios and the respective 95% CI of recall rate of DM vs. FM in two SRs were inconsistency (1.07 [RR, 95% CI: 0.94-1.22] and 0.00695 [RD, 95% CI: 0.00347-0.01042]). Moreover, the risk ratios and the respective 95% CI of recall rate of DBT + DM vs. DM were also inconsistency (1.13 [RR, 95% CI: 0.96-1.32] and 0.72[RR, 95% CI: 0.64-0.80]). The recall rate of FM vs. FFDM and DBT+SM vs. DM were not statistically significant (0.95 [RR, 95% CI: 0.71-1.26] and 1.08 [RR, 95% CI: 0.92-1.26]). The RD of recall rate of DBT was statistically significant lower than DM (-0.0219 [-0.0298, -0.014]).