Journal of the National Cancer Institute Advance Access originally published online on June 10, 2008
JNCI Journal of the National Cancer Institute 2008 100(12):876-887; doi:10.1093/jnci/djn172
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
ARTICLES |
Mammography Facility Characteristics Associated With Interpretive Accuracy of Screening Mammography
Affiliations of authors: Applied Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, MD (ST); Group Health, Center for Health Studies, Seattle, WA (LA); Cancer Research and Biostatistics, Seattle, WA (WEB); Department of Family and Community Medicine, University of California Davis Health System, Sacramento, CA (JJF); Department of Radiology, Lynn Sage Comprehensive Breast Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL (EAB); Oregon Health Sciences University, Portland, OR (PAC); Department of Biostatistics, University of Alabama at Birmingham, Birmingham, AL (GRC); Department of Radiology, University of California School of Medicine, San Francisco, CA (EAS); Department of Radiology, Emory University, Atlanta, GA (CDO); Department of Internal Medicine, University of Washington School of Medicine, Seattle, WA (JGE)
Correspondence to: Stephen Taplin, MD, MPH, 6130 Executive Blvd, MSC 7344, EPN 4005, Bethesda, MD 20892-7344 (e-mail: taplins{at}mail.nih.gov).
Background: Although interpretive performance varies substantially among radiologists, such variation has not been examined among mammography facilities. Understanding sources of facility variation could become a foundation for improving interpretive performance.
Methods: In this cross-sectional study conducted between 1996 and 2002, we surveyed 53 facilities to evaluate associations between facility structure, interpretive process characteristics, and interpretive performance of screening mammography (ie, sensitivity, specificity, positive predictive value [PPV1], and the likelihood of cancer among women who were referred for biopsy [PPV2]). Measures of interpretive performance were ascertained prospectively from mammography interpretations and cancer data collected by the Breast Cancer Surveillance Consortium. Logistic regression and receiver operating characteristic (ROC) curve analyses estimated the association between facility characteristics and mammography interpretive performance or accuracy (area under the ROC curve [AUC]). All P values were two-sided.
Results: Of the 53 eligible facilities, data on 44 could be analyzed. These 44 facilities accounted for 484 463 screening mammograms performed on 237 669 women, of whom 2686 were diagnosed with breast cancer during follow-up. Among the 44 facilities, mean sensitivity was 79.6% (95% confidence interval [CI] = 74.3% to 84.9%), mean specificity was 90.2% (95% CI = 88.3% to 92.0%), mean PPV1 was 4.1% (95% CI = 3.5% to 4.7%), and mean PPV2 was 38.8% (95% CI = 32.6% to 45.0%). The facilities varied statistically significantly in specificity (P < .001), PPV1 (P < .001), and PPV2 (P = .002) but not in sensitivity (P = .99). AUC was higher among facilities that offered screening mammograms alone vs those that offered screening and diagnostic mammograms (0.943 vs 0.911, P = .006), had a breast imaging specialist interpreting mammograms vs not (0.932 vs 0.905, P = .004), did not perform double reading vs independent double reading vs consensus double reading (0.925 vs 0.915 vs 0.887, P = .034), or conducted audit reviews two or more times per year vs annually vs at an unknown frequency (0.929 vs 0.904 vs 0.900, P = .018).
Conclusion: Mammography interpretive performance varies statistically significantly by facility.
| CONTEXT AND CAVEATS Prior knowledge Mammography interpretive performance is known to be influenced by characteristics of the women who are being screened and of the interpreting radiologists. However, the extent to which screening mammography interpretive performance varies by facility-level characteristics is unclear. Study design A cross-sectional survey-based study that examined whether interpretive performance and accuracy vary across mammography facilities after accounting for known determinants of mammography interpretive performance and included 44 facilities, 484 463 screening mammograms performed on 237 669 women, and 2686 breast cancer diagnoses. Contribution Mammography interpretive accuracy was higher among facilities that offered screening mammograms alone vs those that offered screening and diagnostic mammograms; had a breast imaging specialist interpreting mammograms vs not; did not perform double reading vs independent vs consensus double reading; or conducted audit reviews two or more times per year vs annually or at an unknown frequency. Implications Understanding how facility characteristics influence interpretive accuracy could allow women and physicians to choose a mammography facility based on characteristics that are more likely to be associated with higher quality. Radiologists could also change the facilities’ structures or processes to include practices that improve interpretive accuracy. Limitations Characterization of double reading of mammograms was limited. Unmeasured variation among women and radiologists may account for some of the variation associated with facilities. Some facilities were excluded from the analyses because of missing data. Associations were assessed at a single point in time. A number of selection biases may have affected the results.
|
Manuscript received November 5, 2007; revised April 7, 2008; accepted April 22, 2008.
Related Articles in JNCI
CiteULike 
Connotea 
Del.icio.us What's this?
J Natl Cancer Inst 2008 100: 829.
J Natl Cancer Inst 2008 100: 829.
This article has been cited by other articles:
|
|
 |
|
  Screening Mammography: Which Factors Foretell Accuracy? Journal Watch Women's Health, July 10, 2008; 2008(710): 4 - 4. [Full Text]
|
|