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Harms Associated With Mammography Screening (Key Question 2a) (continued)
Table 2. Age-Specific Screening Results From the BCS
|Screening Result||Age Group|
|40-49 y||50-59 y||60-69 y||70-79 y||80-89 y|
|Outcomes per screening round (per 1000 screened), n*|
|False-negative mammography result||1.0||1.1||1.4||1.5||1.4|
|False-positive mammography result||97.8||86.6||79.0||68.8||59.4|
|Screening-detected invasive cancer||1.8||3.4||5.0||6.5||7.0|
|Yield of screening per screening round, n|
|Patients undergoing mammography to diagnose 1 case of invasive breast cancer†||556||294||200||154||143|
|Patients undergoing additional imaging to diagnose 1 case of invasive breast cancer‡||47||22||14||10||8|
|Patients undergoing biopsy to diagnose 1 case of invasive breast cancer§||5||3||2||2||1.5|
BCSC = Breast Cancer Surveillance Consortium; DCIS = ductal carcinoma in situ.
* Calculated from BCSC data of regularly screened women on the basis of results from a single screening round. Rates of additional imaging and biopsies may be underestimated because of incomplete capture of these examinations by the BCSC.
† 1 per rate of screening-detected invasive cancer.
‡ Rate of additional imaging per rate of screening-detected invasive cancer.
§ Rate of biopsy per rate of screening-detected invasive cancer.
A review of RCTs of mammography screening compared the cumulative incidence of breast cancer in intervention and control groups to determine the extent of overdiagnosis.44 In the 5 trials in which the control group did not receive screening, the absolute excess cumulative incidence of invasive and in situ breast cancer attributed to overdiagnosis among women randomly assigned to screening mammography ranged from 0.07 to 0.73 per 1000 woman-years.
Eight studies report estimates of overdiagnosis using different methods.16 Estimates are derived from data from screening programs in Italy, 45 Denmark, 46 and Norway and Sweden; 47 a microsimulation model;48 analysis of incidence data from screening trials,46, 49-50 and a Markov model with data from a screening trial26 and several screening programs. 51 None of these studies provide estimates specific to U.S. samples. Rates of overdiagnosis vary from less than 1%45-46, 49 to 30%,47 with most from 1% to 10%. Estimates differ by outcome (invasive vs. in situ breast cancer), by whether cases are incident or prevalent, and by age. The studies are too heterogeneous to combine statistically.
CBE Screening (Key Questions 1b and 2b)
Few trials have evaluated the effectiveness or harms of CBE in decreasing breast cancer mortality. In countries with widely practiced mammography screening, the use of CBE rests on its additional contribution to mortality reduction. The CNBSS-2 trial, which compares mammography with CBE versus CBE alone, showed no difference in mortality between these 2 approaches.52
Three trials were designed to determine mortality outcomes by using CBE as the primary screening approach in countries with limited health care resources and without mammography screening programs (Appendix Table 2). A randomized trial comparing CBE with no screening was conducted in the Philippines; however, it was discontinued after 1 screening round because of poor community acceptance and is inconclusive.53 Two randomized trials comparing CBE with no screening are ongoing in Egypt54 and India.55
In the pilot study for the Cairo Breast Screening Trial,54 1.2% of women undergoing CBE had subsequent procedures with benign results. Of the 138,392 women examined in the Philippines study, 3479 had abnormal CBEs and 1220 completed diagnostic work-ups.53 Of these women, 34 (3%) had cancer, 563 (46%) had no detectable abnormalities, and 623 (51%) had biopsy results that were benign.
BSE (Key Questions 1c and 2c)
Preliminary results from trials of BSE in Russia and Shanghai were reviewed for the 2002 report,2 and final results have since been published (Appendix Table 2).18,56-57 The effect of BSE on all-cause mortality in St. Petersburg, Russia, a community without routine mammography screening, was evaluated in a trial that met criteria for fair quality.18, 56-57 Despite a significant increase in the number of cases of breast cancer detected when BSE instruction was provided, there was no reduction in all-cause mortality (RR, 1.07 [CI, 0.88 to 1.29]).18 A good-quality randomized trial conducted in Shanghai, China, indicated breast cancer rates of 6.5 per 1000 for women instructed in BSE and 6.7 per 1000 for control participants after 11 years of follow-up.58 The number of women who died of breast cancer was the same in both groups (135 of 132,979 and 131 of 133,085, respectively; RR, 1.03 [CI, 0.81 to 1.31]). Published meta-analyses of randomized trials59-61 and nonrandomized studies59-61 of BSE also indicate no significant differences in breast cancer mortality between BSE and control groups.
In the Russian18 and Shanghai58 trials, more women randomly assigned to BSE had benign biopsy results than women in control groups (RR, 2.05 [CI, 1.80 to 2.33] for women in the Russian study and 1.57 [CI, 1.48 to 1.68] for women in the Shanghai study). A retrospective cohort study of 27 421 women aged 40 years or older in the United States indicated that those performing more frequent or longer-duration BSEs were more likely than women with less frequent and shorter BSEs to have diagnostic mammography or ultrasonography.62 Contrary to the Russian and Shanghai studies, there was no significant association between BSE and biopsy rates in this study.
Table 3 summarizes the evidence for this review. Breast cancer mortality benefits from RCTs of screening are based on estimates of women who were randomly assigned to screening, whereas harms are based on data from women actually screened.
Trials of mammography screening for women aged 39 to 49 years indicate a statistically significant 15% reduction in breast cancer mortality for women randomly assigned to screening versus those assigned to controls. This translates to a number needed to invite for screening to prevent 1 breast cancer death of 1904 (CrI, 929 to 6378). These results are similar to those for women aged 50 to 59 years but less than those for women aged 60 to 69 years. For women aged 70 years or older, results from the Swedish Two-County trial26 of women aged 70 to 74 years indicate no mortality reduction. However, these results are limited by including only a few women from 1 sample. Interpreting trial results stratified by age requires caution because except for the Age trial,29 age-specific results are subanalyses of trials designed for different purposes.
Although the addition of the Age trial29 did not markedly change the results of the meta-analysis, its contribution to the evidence base is important. The Age trial29 is the only trial of mammography that specifically evaluates the effectiveness of screening women in their 40s. It is the largest trial and draws from a community population. It is the most recent trial that reflects current screening, diagnostic, and treatment practices better than its predecessors, particularly those from the pretamoxifen era. As such, it is the most relevant trial. However, its results, although consistent with the meta-analysis in the direction of benefit, are not statistically significant. Also, its applicability to U.S. women is not clear, in light of important differences between mammography screening practices in the United States and the United Kingdom.63
Harms of mammography screening have been identified, but their magnitude and effect are difficult to measure. The absolute level of radiation exposure and corresponding radiation risk from mammography is very low. Special considerations may be needed, however, for women exposed to additional radiation for other purposes or women particularly susceptible to radiation and breast cancer, such as BRCA mutation carriers. Patient adverse experiences, such as pain during procedures and anxiety and other psychological responses, are common but seem to be transient and do not adversely influence future screening practices. This may differ for individual women. Estimates of the magnitude of overdiagnosis vary depending on the analytic approach used. These estimates are difficult to apply because, for individual women, it is not known which types of cancer will progress, how quickly cancer will advance, and expected lifetimes.
The effectiveness of CBE has not been proven in large, well-designed trials. Current ongoing trials are limited to countries that do not provide routine mammography screening, which restricts their applicability to the United States. Work-ups for false-positive findings subject women to additional imaging and procedures countering the potential benefits of this low-technology approach. For BSE, the Russian18 and Shanghai58 trials simultaneously showed no reductions in mortality and increased numbers of benign biopsy results done as a result of BSE instruction.
Although more information is available to determine the benefits and harms of routine breast cancer screening in average-risk women, questions remain unanswered. The least amount of data is available for women aged 70 years or older, which is a rapidly growing population in the United States. Recent observational studies indicate that regular screening mammography among older women is associated with earlier-stage disease64-65 and lower breast cancer mortality rates.65 For the many older women who might live 20 to 30 years longer, breast cancer detection and early treatment could reduce morbidity as well as mortality, thereby optimizing independence, function, quality of life, and costs of care in the final years.
Breast cancer is a continuum of entities, not just 1 disease that needs to be taken into account when considering screening and treatment options and when balancing benefits and harms. None of the screening trials consider breast cancer in this manner. As diagnostic and treatment experiences become more individualized66 and include patient preferences, it becomes even more difficult to characterize benefits and harms in a general way.
New technologies, such as digital mammography and MRI, have become widely used in the United States without definitive studies of their effect on screening. Consumer expectations that new technology is better than old may obscure potential adverse effects, such as higher false-positive results and expense. No screening trials incorporating newer technology have been published, and estimates of benefits and harms in this report are based predominantly on studies of film mammography. No definitive studies of the appropriate interval for mammography screening exist, although trial data reflect screening intervals from 12 to 33 months.
Our meta-analysis of mammography screening trials indicates breast cancer mortality benefit for all age groups from 39 to 69 years, with insufficient data for older women. False-positive results are common in all age groups and lead to additional imaging and biopsies. Women aged 40 to 49 years experience the highest rate of additional imaging, whereas their biopsy rate is lower than that for older women. Mammography screening at any age is a tradeoff of a continuum of benefits and harms. The ages at which this tradeoff becomes acceptable to individuals and society are not clearly resolved by the available evidence.
1. U.S. Preventive Services Task Force. Screening for breast cancer: recommendations and rationale. Ann Intern Med 2002;137:344-6. [PMID: 12204019]
2. Humphrey L, Chan BKS, Detlefsen S, Helfand M. Screening for breast cancer: systematic evidence review, 2002. Accessed at www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=hstat3.chapter.27509 on 14 September 2009.
3. Humphrey LL, Helfand M, Chan BK, Woolf SH. Breast cancer screening: a summary of the evidence for the U.S. Preventive Services Task Force. Ann Intern Med 2002;137:347-60. [PMID: 12204020]
4. American Cancer Society. Statistics for 2008. Accessed at http://www.cancer.org/docroot/STT/stt_0_2008.asp?sitearea=STT&level=1 on 14 September 2009.
5. Ries LAG, Harkins D, Krapcho M, Mariotto A, Miller BA, Feuer EJ, et al. SEER Cancer Statistics Review, 1975-2003. Bethesda, MD: National Cancer Institute. Accessed at http://seer.cancer.gov/csr/1975_2003/ on 14 September 2009.
6. Ravdin PM, Cronin KA, Howlader N, Berg CD, Chlebowski RT, Feuer EJ, et al. The decrease in breast-cancer incidence in 2003 in the United States. N Engl J Med 2007;356:1670-4. [PMID: 17442911]
7. Kerlikowske K, Miglioretti DL, Buist DS, Walker R, Carney PA; National Cancer Institute-Sponsored Breast Cancer Surveillance Consortium. Declines in invasive breast cancer and use of postmenopausal hormone therapy in a screening mammography population. J Natl Cancer Inst 2007;99:1335-9. [PMID: 17698950]
8. Chagpar AB, McMasters KM. Trends in mammography and clinical breast examination: a population-based study. J Surg Res 2007;140:214-9. [PMID: 17418862]
9. American Cancer Society. Breast Cancer Facts & Figures 2005-2006. Accessed at http://www.cancer.org/downloads/STT/CAFF2005BrF.pdf on 14 September 2009.
10. Edwards BK, Brown ML, Wingo PA, Howe HL, Ward E, Ries LA, et al. Annual report to the nation on the status of cancer, 1975-2002, featuring population-based trends in cancer treatment. J Natl Cancer Inst 2005;97:1407-27. [PMID: 16204691]
11. Berry DA, Cronin KA, Plevritis SK, Fryback DG, Clarke L, Zelen M, et al; Cancer Intervention and Surveillance Modeling Network (CISNET) Collaborators. Effect of screening and adjuvant therapy on mortality from breast cancer. N Engl J Med 2005;353:1784-92. [PMID: 16251534]
12. Saslow D, Boetes C, Burke W, Harms S, Leach MO, Lehman CD, et al; American Cancer Society Breast Cancer Advisory Group. American Cancer Society guidelines for breast screening with MRI as an adjunct to mammography. CA Cancer J Clin 2007;57:75-89. [PMID: 17392385]
13. Flobbe K, Bosch AM, Kessels AG, Beets GL, Nelemans PJ, von Meyenfeldt MF, et al. The additional diagnostic value of ultrasonography in the diagnosis of breast cancer. Arch Intern Med 2003;163:1194-9. [PMID: 12767956]
14. Bedrosian I, Mick R, Orel SG, Schnall M, Reynolds C, Spitz FR, et al. Changes in the surgical management of patients with breast carcinoma based on preoperative magnetic resonance imaging. Cancer 2003;98:468-73. [PMID: 12879462]
15. Day NE. Overdiagnosis and breast cancer screening [Editorial]. Breast Cancer Res 2005;7:228-9. [PMID: 16168144]
16. Nelson HD, Tyne K, Naik A, Bougatsos C, Chan BK, Nygren P, et al. Screening for Breast Cancer: Systematic Evidence Review Update for the U.S. Preventive Services Task Force. Evidence Review Update. (Prepared by the Oregon Evidence-based Practice Center under contract 290-02-0024 with the Agency for Healthcare Research and Quality.) Rockville, MD: Agency for Healthcare Research and Quality; 2009.
17. Web of Science. Accessed at http://isiwebofknowledge.com/products_tools/multidisciplinary/webofscience/ on 14 September 2009.
18. Semiglazov VF, Manikhas AG, Moiseenko VM, Protsenko SA, Kharikova RS, Seleznev IK, et al. [Results of a prospective randomized investigation [Russia (St.Petersburg)/WHO] to evaluate the significance of self-examination for the early detection of breast cancer]. Vopr Onkol 2003;49:434-41. [PMID: 14569932]
19. National Cancer Institute. Breast Cancer Surveillance Consortium. Accessed at http://breastscreening.cancer.gov/ on 14 September 2009.
20. Ballard-Barbash R, Taplin SH, Yankaskas BC, Ernster VL, Rosenberg RD, Carney PA, et al. Breast Cancer Surveillance Consortium: a national mammography screening and outcomes database. AJR Am J Roentgenol. 1997;169: 1001-8. [PMID: 9308451]
21. Harris RP, Helfand M, Woolf SH, Lohr KN, Mulrow CD, Teutsch SM, et al; Methods Work Group, Third US Preventive Services Task Force. Current methods of the US Preventive Services Task Force: a review of the process. Am J Prev Med 2001;20:21-35. [PMID: 11306229]
22. Development Core Team. R: A language and environment for statistical computing [Expert program]. Vienna, Austria: R Foundation for Statistical Computing; 2006.
23. Thomas A, O'Hara B, Ligges U, Sturtz S. Making BUGS open. R News 2006;6:12-17.24.
24. D'Orsi CJ, Bassett LW, Berg WA. Follow-up and outcome monitoring. In: Breast Imaging Reporting and Data System: ACR BIRADS. 4th ed. Reston, VA: American Coll of Radiology; 2003:229-51.
25. Rosenberg RD, Yankaskas BC, Abraham LA, Sickles EA, Lehman CD, Geller BM, et al. Performance benchmarks for screening mammography. Radiology 2006;241:55-66. [PMID: 16990671]
26. Nyström L, Andersson I, Bjurstam N, Frisell J, Nordenskjöld B, Rutqvist LE. Long-term effects of mammography screening: updated overview of the Swedish randomised trials. Lancet 2002;359:909-19. [PMID: 11918907]
27. Habbema JD, van Oortmarssen GJ, van Putten DJ, Lubbe JT, van der Maas PJ. Age-specific reduction in breast cancer mortality by screening: an analysis of the results of the Health Insurance Plan of Greater New York study. J Natl Cancer Inst. 1986;77:317-20. [PMID: 3461193]
28. Miller AB, To T, Baines CJ, Wall C. The Canadian National Breast Screening Study-1: breast cancer mortality after 11 to 16 years of follow-up. A randomized screening trial of mammography in women age 40 to 49 years. Ann Intern Med 2002;137:305-12. [PMID: 12204013]
29. Moss SM, Cuckle H, Evans A, Johns L, Waller M, Bobrow L; Trial Management Group. Effect of mammographic screening from age 40 years on breast cancer mortality at 10 years' follow-up: a randomised controlled trial. Lancet 2006;368:2053-60. [PMID: 17161727]
30. Bjurstam N, Björneld L, Warwick J, Sala E, Duffy SW, Nyström L, et al. The Gothenburg Breast Screening Trial. Cancer 2003;97:2387-96. [PMID: 12733136]
31. Tabar L, Fagerberg G, Chen HH, Duffy SW, Smart CR, Gad A, et al. Efficacy of breast cancer screening by age. New results from the Swedish Two-County Trial. Cancer. 1995;75:2507-17. [PMID: 7736395]
32. Tabár L, Vitak B, Chen HH, Duffy SW, Yen MF, Chiang CF, et al. The Swedish Two-County Trial twenty years later. Updated mortality results and new insights from long-term follow-up. Radiol Clin North Am 2000;38:625-51. [PMID: 10943268]
33. Spelic DC. Dose and image quality in mammography: trends during the first decade of MQSA. Silver Spring, MD: U.S. Food and Drug Administration; 2003. Accessed at http://www.fda.gov/Radiation-EmittingProducts/MammographyQualityStandardsActandProgram/FacilityScorecard/ucm113606.htm on 13 November 2009.
34. Armstrong K, Moye E, Williams S, Berlin JA, Reynolds EE. Screening mammography in women 40 to 49 years of age: a systematic review for the American College of Physicians. Ann Intern Med 2007;146:516-26. [PMID: 17404354]
35. John EM, Phipps AI, Knight JA, Milne RL, Dite GS, Hopper JL, et al. Medical radiation exposure and breast cancer risk: findings from the Breast Cancer Family Registry. Int J Cancer 2007;121:386-94. [PMID: 17372900]
36. Brett J, Bankhead C, Henderson B, Watson E, Austoker J. The psychological impact of mammographic screening. A systematic review. Psychooncology 2005;14:917-38. [PMID: 15786514]
37. Brewer NT, Salz T, Lillie SE. Systematic review: the long-term effects of false-positive mammograms. Ann Intern Med 2007;146:502-10. [PMID: 17404352]
38. Mushlin AI, Kouides RW, Shapiro DE. Estimating the accuracy of screening mammography: a meta-analysis. Am J Prev Med. 1998;14:143-53. [PMID: 9631167]
39. Olivotto IA, Kan L, Coldman AJ. False positive rate of screening mammography [Letter]. N Engl J Med. 1998;339:560; author reply 563. [PMID: 9714619]
40. Hofvind S, Thoresen S, Tretli S. The cumulative risk of a false-positive recall in the Norwegian Breast Cancer Screening Program. Cancer 2004;101:1501-7. [PMID: 15378474]
41. Elmore JG, Barton MB, Moceri VM, Polk S, Arena PJ, Fletcher SW. Ten-year risk of false positive screening mammograms and clinical breast examinations. N Engl J Med. 1998;338:1089-96. [PMID: 9545356]
42. Yankaskas BC, Taplin SH, Ichikawa L, Geller BM, Rosenberg RD, Carney PA, et al. Association between mammography timing and measures of screening performance in the United States. Radiology 2005;234:363-73. [PMID: 15670994]
43. Drossaert CH, Boer H, Seydel ER. Does mammographic screening and a negative result affect attitudes towards future breast screening? J Med Screen 2001;8:204-12. [PMID: 11743037]
44. Moss S. Overdiagnosis and overtreatment of breast cancer: overdiagnosis in randomised controlled trials of breast cancer screening. Breast Cancer Res 2005; 7:230-4. [PMID: 16168145]
45. Paci E, Miccinesi G, Puliti D, Baldazzi P, De Lisi V, Falcini F, et al. Estimate of overdiagnosis of breast cancer due to mammography after adjustment for lead time. A service screening study in Italy. Breast Cancer Res 2006;8:R68. [PMID: 17147789]
46. Olsen AH, Agbaje OF, Myles JP, Lynge E, Duffy SW. Overdiagnosis, sojourn time, and sensitivity in the Copenhagen mammography screening program. Breast J 2006;12:338-42. [PMID: 16848843]
47. Zahl PH, Strand BH, Maehlen J. Incidence of breast cancer in Norway and Sweden during introduction of nationwide screening: prospective cohort study. BMJ 2004;328:921-4. [PMID: 15013948]
48. de Koning HJ, Draisma G, Fracheboud J, de Bruijn A. Overdiagnosis and overtreatment of breast cancer: microsimulation modelling estimates based on observed screen and clinical data. Breast Cancer Res 2006;8:202. [PMID: 16524452]
49. Duffy SW, Agbaje O, Tabar L, Vitak B, Bjurstam N, Björneld L, et al. Overdiagnosis and overtreatment of breast cancer: estimates of overdiagnosis from two trials of mammographic screening for breast cancer. Breast Cancer Res 2005;7:258-65. [PMID: 16457701]
50. Zackrisson S, Andersson I, Janzon L, Manjer J, Garne JP. Rate of overdiagnosis of breast cancer 15 years after end of Malmö mammographic screening trial: follow-up study. BMJ 2006;332:689-92. [PMID: 16517548]
51. Yen MF, Tabár L, Vitak B, Smith RA, Chen HH, Duffy SW. Quantifying the potential problem of overdiagnosis of ductal carcinoma in situ in breast cancer screening. Eur J Cancer 2003;39:1746-54. [PMID: 12888370]
52. Miller AB, To T, Baines CJ, Wall C. Canadian National Breast Screening Study-2: 13-year results of a randomized trial in women aged 50-59 years. J Natl Cancer Inst 2000;92:1490-9. [PMID: 10995804]
53. Pisani P, Parkin DM, Ngelangel C, Esteban D, Gibson L, Munson M, et al. Outcome of screening by clinical examination of the breast in a trial in the Philippines. Int J Cancer 2006;118:149-54. [PMID: 16049976]
54. Boulos S, Gadallah M, Neguib S, Essam E, Youssef A, Costa A, et al. Breast screening in the emerging world: high prevalence of breast cancer in Cairo. Breast 2005;14:340-6. [PMID: 16131468]
55. National Cancer Institute. U.S. National Institutes of Health. Cancer control research. Accessed at http://cancercontrol.cancer.gov/grants/abstract.asp?applid=6965060 on 14 September 2009.
56. Semiglazov VF, Moiseenko VM, Manikhas AG, Protsenko SA, Kharikova RS, Popova RT, et al. [Interim results of a prospective randomized study of self-examination for early detection of breast cancer (Russia/St.Petersburg/WHO)]. Vopr Onkol. 1999;45:265-71. [PMID: 10443229]
57. Semiglazov VF, Moiseyenko VM, Bavli JL, Migmanova NSh, Seleznyov NK, Popova RT, et al. The role of breast self-examination in early breast cancer detection (results of the 5-years USSR/WHO randomized study in Leningrad). Eur J Epidemiol. 1992;8:498-502. [PMID: 1397215]
58. Thomas DB, Gao DL, Ray RM, Wang WW, Allison CJ, Chen FL, et al. Randomized trial of breast self-examination in Shanghai: final results. J Natl Cancer Inst 2002;94:1445-57. [PMID: 12359854]
59. Hackshaw AK, Paul EA. Breast self-examination and death from breast cancer: a meta-analysis. Br J Cancer 2003;88:1047-53. [PMID: 12671703]
60. Baxter N; Canadian Task Force on Preventive Health Care. Preventive health care, 2001 update: should women be routinely taught breast self-examination to screen for breast cancer? CMAJ 2001;164:1837-46. [PMID: 11450279]
61. Kösters JP, Gøtzsche PC. Regular self-examination or clinical examination for early detection of breast cancer. Cochrane Database Syst Rev 2003: CD003373. [PMID: 12804462]
62. Tu SP, Reisch LM, Taplin SH, Kreuter W, Elmore JG. Breast self-examination: self-reported frequency, quality, and associated outcomes. J Cancer Educ. 2006;21:175-81. [PMID: 17371185]
63. Smith-Bindman R, Chu PW, Miglioretti DL, Sickles EA, Blanks R, Ballard-Barbash R, et al. Comparison of screening mammography in the United States and the United kingdom. JAMA 2003;290:2129-37. [PMID: 14570948]
64. Badgwell BD, Giordano SH, Duan ZZ, Fang S, Bedrosian I, Kuerer HM, et al. Mammography before diagnosis among women age 80 years and older with breast cancer. J Clin Oncol 2008;26:1-8. [PMID: 18427152]
65. Galit W, Green MS, Lital KB. Routine screening mammography in women older than 74 years: a review of the available data. Maturitas 2007;57:109-19. [PMID: 17336004]
66. Tripathy D. Targeted therapies in breast cancer. Breast J 2005;11 Suppl 1:S30-5. [PMID: 15725114]
67. Smeeth L, Haines A, Ebrahim S. Numbers needed to treat derived from meta-analyses-sometimes informative, usually misleading. BMJ. 1999;318: 1548-51. [PMID: 10356018]
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Source: Nelson HD, Tyne K, Naik A, Bougatsos B, Chan BK, Humphrey L. Screening for Breast Cancer: An Update for the U.S. Preventive Services Task Force. Ann Intern Med 2009;151:727-37.
This report was conducted by the Oregon Evidence-based Practice Center under contract to the Agency for Healthcare Research and Quality (contract 290-02-0024); the Veteran's Administration Women's Health Fellowship (Dr. Tyne); and the Oregon Health & Science University Department of Surgery in conjunction with the Human Investigators Program (Dr. Naik). Data collection for some of this work was supported by the National Cancer Institute-funded BCSC cooperative agreement (U01CA63740, U01CA86076, U01CA86082, U01CA63736, U01CA70013, U01CA69976, U01CA63731, U01CA70040).
The authors acknowledge the contributions of AHRQ Project Officer Mary Barton, MD, MPP, and USPSTF leads Russ Harris, MD, MPH; Allen Dietrich, MD; Carol Loveland-Cherry, PhD, RN; Judith Ockene, PhD, Med; and Bernadette Melnyk, PhD, RN, CPNP/NPP. The authors thank the BCSC investigators, participating mammography facilities, and radiologists for the data used in this project. A list of the BCSC investigators and procedures for requesting BCSC data for research purposes are available at http://breastscreening.cancer.gov/. They also thank Patricia A. Carney, PhD; Steve Taplin, MD; Sebastien Haneuse, PhD; and Rod Walker, MS; for direct work with investigators, along with Andrew Hamilton, MLS, MS, for literature searches, and Sarah Baird, MS, for managing the bibliography at the Oregon Evidence-based Practice Center at the Oregon Health & Science University.
AHRQ Publication No. 10-05142-EF-5
Current as of November 2009
Nelson HD, Tyne K, Naik A, Bougatsos B, Chan BK, Humphrey L. Screening for Breast Cancer: An Update for the U.S. Preventive Services Task Force. AHRQ Publication No. 10-05142-EF-5, November 2009. http://www.uspreventiveservicestaskforce.org/uspstf09/breastcancer/brcanup.htm