NCCN Guidelines® Insights: Breast Cancer Screening and Diagnosis, Version 1.2023.

The NCCN Guidelines for Breast Cancer Screening and Diagnosis provide health care providers with a practical, consistent framework for screening and evaluating a spectrum of clinical presentations and breast lesions. The NCCN Breast Cancer Screening and Diagnosis Panel is composed of a multidisciplinary team of experts in the field, including representation from medical oncology, gynecologic oncology, surgical oncology, internal medicine, family practice, preventive medicine, pathology, diagnostic and interventional radiology, as well as patient advocacy. The NCCN Breast Cancer Screening and Diagnosis Panel meets at least annually to review emerging data and comments from reviewers within their institutions to guide updates to existing recommendations. These NCCN Guidelines Insights summarize the panel's decision-making and discussion surrounding the most recent updates to the guideline's screening recommendations.

Artificial Intelligence Applications in Breast Imaging: Current Status and Future Directions.

Attempts to use computers to aid in the detection of breast malignancies date back more than 20 years. Despite significant interest and investment, this has historically led to minimal or no significant improvement in performance and outcomes with traditional computer-aided detection. However, recent advances in artificial intelligence and machine learning are now starting to deliver on the promise of improved performance. There are at present more than 20 FDA-approved AI applications for breast imaging, but adoption and utilization are widely variable and low overall. Breast imaging is unique and has aspects that create both opportunities and challenges for AI development and implementation. Breast cancer screening programs worldwide rely on screening mammography to reduce the morbidity and mortality of breast cancer, and many of the most exciting research projects and available AI applications focus on cancer detection for mammography. There are, however, multiple additional potential applications for AI in breast imaging, including decision support, risk assessment, breast density quantitation, workflow and triage, quality evaluation, response to neoadjuvant chemotherapy assessment, and image enhancement. In this review the current status, availability, and future directions of investigation of these applications are discussed, as well as the opportunities and barriers to more widespread utilization.

Masson's tumor of the reconstructed breast.

Intravascular papillary endothelial hyperplasia (Masson's Tumor) is a rare benign endothelial vascular lesion that can mimic angiosarcoma if not properly recognized. It represents less than 2% of all vascular tumors, but has been seen in the postradiation setting, which also makes differentiating it from angiosarcoma crucial. It is classically characterized as a circumscribed, intravascular mass that is hypoechoic on ultrasound, and T1 isointense and T2 heterogenous on MRI with variable enhancement. Histologically, it demonstrates papillary architecture without significant atypia, and associated vascular thrombus. Although it typically occurs in the soft tissues of the trunk and neck, a very small percentage of cases have been found in the breast. The following case will involve a 64-year-old female with a Masson's tumor involving the capsule of her left breast implant, in the setting of previously treated ductal carcinoma in situ, which was surgically excised and irradiated over 20 years prior.

A Method to Deliver Automated and Tailored Intervention Content: 24-month Clinical Trial.

BACKGROUND: The use of digital technologies and software allows for new opportunities to communicate and engage with research participants over time. When software is coupled with automation, we can engage with research participants in a reliable and affordable manner. Research Electronic Data Capture (REDCap), a browser-based software, has the capability to send automated text messages. This feature can be used to automate delivery of tailored intervention content to research participants in interventions, offering the potential to reduce costs and improve accessibility and scalability. OBJECTIVE: This study aimed to describe the development and use of 2 REDCap databases to deliver automated intervention content and communication to index participants and their partners (dyads) in a 2-arm, 24-month weight management trial, Partner2Lose. METHODS: Partner2Lose randomized individuals with overweight or obesity and cohabitating with a partner to a weight management intervention alone or with their partner. Two databases were developed to correspond to 2 study phases: one for weight loss initiation and one for weight loss maintenance and reminders. The weight loss initiation database was programmed to send participants (in both arms) and their partners (partner-assisted arm) tailored text messages during months 1-6 of the intervention to reinforce class content and support goal achievement. The weight maintenance and reminder database was programmed to send maintenance-related text messages to each participant (both arms) and their partners (partner-assisted arm) during months 7-18. It was also programmed to send text messages to all participants and partners over the course of the 24-month trial to remind them of group classes, dietary recall and physical activity tracking for assessments, and measurement visits. All text messages were delivered via Twilio and were unidirectional. RESULTS: Five cohorts, comprising 231 couples, were consented and randomized in the Partner2Lose trial. The databases will send 53,518 automated, tailored text messages during the trial, significantly reducing the need for staff to send and manage intervention content over 24 months. The cost of text messaging will be approximately US $450. Thus far, there is a 0.004% known error rate in text message delivery. CONCLUSIONS: Our trial automated the delivery of tailored intervention content and communication using REDCap. The approach described provides a framework that can be used in future behavioral health interventions to create an accessible, reliable, and affordable method for intervention delivery and engagement that requires minimal trial-specific resources and personnel time. TRIAL REGISTRATION: ClinicalTrials.gov NCT03801174; https://clinicaltrials.gov/ct2/show/NCT03801174?term=NCT03801174.

The lateral arm device for mammographic breast procedures: overview of its uses, safety, and efficacy.

Introduction: Percutaneous image-guided biopsy is the procedure of choice for diagnosing suspicious abnormalities on breast imaging. Stereotactic, ultrasound, and magnetic resonance imaging are used for image-guided breast biopsies. Stereotactic guidance uses mammography to localize lesions and facilitate placement of a core biopsy needle. The first systems used a vertical-approach needle insertion. The lateral arm device, which is the most recent advancement in stereotactic biopsies and pre-surgical localization allows procedures to be performed using a needle insertion parallel to the compression plate.Areas covered: The lateral arm device was introduced to the market in 2007 and is the first device of its kind. In this article we review the mechanism of this device, the risks and benefits of the device and other the different other modalities utilized to biopsy and localize the breast. We summarize the current literature on this device along with our own experiences utilizing this device.Expert opinion: The lateral arm device has changed the face of stereotactic-guided breast biopsies and localizations by allowing a new approach to perform these procedures. It has improved care to patients by allowing us to get to areas previously not within the biopsy window, decreased biopsy time and increased patient throughput.

Long-term safety and efficacy of breast biopsy markers in clinical practice.

Objective: Percutaneous breast and axillary core biopsy followed by marker placement are integral parts of a breast imager's practice benefiting both patients and clinicians. Marker placement is the standard to facilitate future care. The purpose of this study is to characterize the safety and performance of MammoMARK, CorMARK, and HydroMARK biopsy markers by evaluating device-related adverse events, device deficiencies, and long-term safety.Methods: A retrospective review of three radiology practices identified patients who underwent image-guided breast or axillary biopsies followed by marker placement between 1 January 2012 and 1 January 2017. Medical records were reviewed with adverse events related to marker placement and use recorded.Results: 768 markers were placed with three (0.4%) events recorded. Two device deficiencies and one non-serious adverse event occurred in three patients. Device deficiency events involved user errors deploying the markers, one to inability to locate the marker on post-biopsy imaging, and the second to misplacement relative to biopsy target. One non-serious adverse event involved inability to locate/retain the marker in a surgically resected specimen. No serious adverse events were reported.Conclusion: Placement of breast biopsy markers is safe with minimal associated risks. Issues related to device malfunction, durability, reliability, safety, or performance were not reported.

Diagnostic Accuracy of Digital Breast Tomosynthesis in the Evaluation of Palpable Breast Abnormalities.

RATIONALE AND OBJECTIVES: The role of digital breast tomosynthesis (DBT) in evaluating palpable abnormalities has not been evaluated and its accuracy compared to 2D mammography is unknown. The purpose of this study was to evaluate combined 2D mammography, DBT, and ultrasound (US) at palpable sites. MATERIALS AND METHODS: Two breast imagers reviewed blinded consecutive cases with combined 2D mammograms and DBT examinations performed for palpable complaints. By consensus, 2D and DBT findings were recorded and compared to US. Patient characteristics, demographics, subsequent workup, and outcome were recorded. RESULTS: A total of 229 sites in 188 patients were included, with 50 biopsies performed identifying 18 cancers. All 18 cancers were identified on 2D and US, whereas 17 cancers were identified on DBT. Cancer detection sensitivities for 2D, DBT, and US were 100.0%, 94.4%, and 100.0%. The negative predictive value, when combined with US, was 100% for both. The sensitivity and the specificity for both benign and malignant findings with 2D and DBT were 70.5% versus 75.4% (P = 0.07) and 95.3% versus 99.1% (P = 0.125). Palpable findings not identified by 2D and DBT were smaller than those identified (11.5 ± 8.3 mm vs 23.9 ± 12.8 mm, P < 0.001). Patients with dense breasts were more likely to have mammographically occult findings than patients with nondense breasts (27.4% vs 8.3%). CONCLUSIONS: DBT did not improve cancer detection over 2D or US. Both mammographic modalities failed to identify sonographically confirmed findings primarily in dense breasts. The diagnostic use of DBT at palpable sites provided limited benefit over combined 2D and US. When utilizing DBT, US should be performed to adequately characterize palpable sites.

A comparative effectiveness study of eSource used for data capture for a clinical research registry.

OBJECTIVE: This pilot study compared eSource-enabled versus traditional manual data transcription (non-eSource methods) for the collection of clinical registry information. The primary study objective was to compare the time spent completing registry forms using eSource versus non-eSource methods The secondary objectives were to compare data quality associated with these two data capture methods and the flexibility of the workflows. This study directly addressed fundamental questions relating to eSource adoption: what time-savings can be realized, and to what extent does eSource improve data quality. MATERIALS AND METHODS: The study used time and motion methods to compare eSource versus non-eSource data capture workflows for a single center OB/GYN registry. Direct observation by industrial engineers using specialized computer software captured keystrokes, mouse clicks and video recordings of the study team in their normal work environment completing real-time data collection. RESULTS: The overall average data capture time was reduced with eSource versus non-eSource methods (difference, 151s per case; eSource, 1603s; non-eSource, 1754s; p=0.051). The average data capture time for the demographic data was reduced (difference, 79s per case; eSource, 133s; non-eSource, 213s; p<0.001). This represents a 37% time reduction (95% confidence interval 27% to 47%). eSourced data field transcription errors were also reduced (eSource, 0%; non-eSource, 9%). CONCLUSION: The use of eSource versus traditional data transcription was associated with a significant reduction in data entry time and data quality errors. Further studies in other settings are needed to validate these results.

An Assessment of Pathology Resident Access to and Use of Technology: A Nationwide Survey.

CONTEXT: - Current technologies including digital slide scanners and handheld devices can revolutionize clinical practice and pathology graduate medical education (GME). The extent to which these technologies are used in pathology GME is unknown. OBJECTIVES: - To determine the types of technologies used, usage amount, and how they are integrated into pathology residency/fellowship programs nationwide. DESIGN: - A 40-question online survey for residents/fellows was developed and administered via the Research Electronic Data Capture System after institutional review board approval. RESULTS: - Fifty-two program directors (37%) gave permission for participation. One-hundred seventy-one responses were received (18% response rate). Most respondents have access to personal technology (laptop = 78% [134 of 171]), smartphone = 81% [139 of 171], tablet = 49% [84 of 171]), and Web-based digital slide collections (82%, 141 of 171). Few residents are provided electronic devices by their programs (laptop = 22% [38 of 171], smartphone = 0.5% [1 of 171], and tablet = 12% [21 of 171]). Fifty-nine percent have access to digital slide scanners, 33% have access to a program-created database of digitized slides, and 52% use telepathology. Fifteen percent have access to asynchronous learning. Of those with access to video-recorded conferences, 89% review them. Program size was significantly positively correlated with resident access to program-provided laptops (P = .02) and tablets (P < .001), digital slide scanners (P = .01), and telepathology (P = .001). Of all devices, program-provided laptops are used most for professional work (60.5% use this device for more than 5 hours per day). CONCLUSIONS: - Most residents report access to multiple types of innovative technology, but incorporation of these tools within pathology training programs is highly variable. Opportunities for incorporating innovative technologies exist and could be further explored.

Impact of the Addition of Digital Breast Tomosynthesis (DBT) to Standard 2D Digital Screening Mammography on the Rates of Patient Recall, Cancer Detection, and Recommendations for Short-term Follow-up.

RATIONALE AND OBJECTIVES: The addition of digital breast tomosynthesis (DBT) to digital screening mammography (DM) has been shown to decrease recall rates and improve cancer detection rates, but there is a lack of data regarding the impact of DBT on rates of short-term follow-up. We assessed possible changes in performance measures with the introduction of DBT at our facility. MATERIALS AND METHODS: In our observational study, databases were used to compare rates of recall, short-term follow-up, biopsy, and cancer detection between women undergoing DM without (n = 10,477) and women undergoing DM with (n = 2304) the addition of DBT. Regression analysis was performed to determine associations with patient age, breast density, and availability of comparison examinations. RESULTS: The addition of DBT resulted in significantly lower recall rates (16%-14%, P = .017), higher rates of biopsy (12.7%-19.1%, P < .01), and increased detection of ductal carcinoma in situ, with a difference of 2.3 cases per 1000 screens (P = .044). A 33% increase in cancer detection rates was observed with DBT, which did not reach statistical significance. Short-term follow-up of probably benign findings was 80% higher in the DBT group (odds ratio = 1.80, 95% confidence interval = 1.38-2.36, P < .001). CONCLUSIONS: To our knowledge, we are the first to study the impact of DBT on rates of short-term follow-up, and observed an 80% increase over the DM group. Further research is needed to determine the malignancy rate of Breast Imaging Reporting and Data System 3 lesions detected with DBT, and establish appropriate follow-up to maximize cancer detection while minimizing expense and patient anxiety.

Quantification of breast stiffness using MR elastography at 3 Tesla with a soft sternal driver: A reproducibility study.

PURPOSE: Previous studies of breast MR elastography (MRE) evaluated the technique at magnetic field strengths of 1.5 Tesla (T) with the breast in contact with the driver. The aim of this study is to evaluate breast stiffness measurements and their reproducibility using a soft sternal driver at 3T and compare the results with qualitative measures of breast density. MATERIALS AND METHODS: Twenty-two healthy volunteers each underwent two separate breast MRE scans in a 3T MRI. MRE vibrations were introduced into the breasts at 60 Hz using a soft sternal driver and axial slices were collected using a gradient echo MRE sequence. Mean stiffness measurements were calculated for each volunteer as well as a measure of reproducibility using concordance correlation between scans. Mean stiffness values for each volunteer were assessed and related to amounts of fibroglandular tissue (i.e., breast lobules, ducts, and fibrous connective tissue). RESULTS: The stiffness values were reproducible with a significant P-value < 0.0001 between two scans with concordance correlation of 0.87 and 0.91 for center slice and grouping all slices, respectively. Volunteers with dense breasts (i.e., higher grades of fibroglandular tissue) had mean stiffness values of 0.96 kPa (center slice) and 0.92 kPa (all slices) while those without dense breasts had mean stiffness values of 0.85 kPa (center slice) and 0.83 kPa (all slices) (P ≤ 0.05). CONCLUSION: Breast MRE is a reproducible technique at 3T using a soft sternal driver. Dense breasts had significantly higher stiffness measurements compared with nondense breasts. LEVEL OF EVIDENCE: 2 J. MAGN. RESON. IMAGING 2017;45:1379-1384.

Retooling institutional support infrastructure for clinical research.

Clinical research activities at academic medical centers are challenging to oversee. Without effective research administration, a continually evolving set of regulatory and institutional requirements can divert investigator and study team attention away from a focus on scientific gain, study conduct, and patient safety. However, even when the need for research administration is recognized, there can be struggles over what form it should take. Central research administration may be viewed negatively, with individual groups preferring to maintain autonomy over processes. Conversely, a proliferation of individualized approaches across an institution can create inefficiencies or invite risk. This article describes experiences establishing a unified research support office at the Duke University School of Medicine based on a framework of customer support. The Duke Office of Clinical Research was formed in 2012 with a vision that research administration at academic medical centers should help clinical investigators navigate the complex research environment and operationalize research ideas. The office provides an array of services that have received high satisfaction ratings. The authors describe the ongoing culture change necessary for success of the unified research support office. Lessons learned from implementation of the Duke Office of Clinical Research may serve as a model for other institutions undergoing a similar transition.

Influences of Radiology Trainees on Screening Mammography Interpretation.

PURPOSE: Participation of radiology trainees in screening mammographic interpretation is a critical component of radiology residency and fellowship training. The aim of this study was to investigate and quantify the effects of trainee involvement on screening mammographic interpretation and diagnostic outcomes. METHODS: Screening mammograms interpreted at an academic medical center by six dedicated breast imagers over a three-year period were identified, with cases interpreted by an attending radiologist alone or in conjunction with a trainee. Trainees included radiology residents, breast imaging fellows, and fellows from other radiology subspecialties during breast imaging rotations. Trainee participation, patient variables, results of diagnostic evaluations, and pathology were recorded. RESULTS: A total of 47,914 mammograms from 34,867 patients were included, with an overall recall rate for attending radiologists reading alone of 14.7% compared with 18.0% when involving a trainee (P < .0001). Overall cancer detection rate for attending radiologists reading alone was 5.7 per 1,000 compared with 5.2 per 1,000 when reading with a trainee (P = .517). When reading with a trainee, dense breasts represented a greater portion of recalls (P = .0001), and more frequently, greater than one abnormality was described in the breast (P = .013). Detection of ductal carcinoma in situ versus invasive carcinoma or invasive cancer type was not significantly different. The mean size of cancers in patients recalled by attending radiologists alone was smaller, and nodal involvement was less frequent, though not statistically significantly. CONCLUSIONS: These results demonstrate a significant overall increase in recall rate when interpreting screening mammograms with radiology trainees, with no change in cancer detection rate. Radiology faculty members should be aware of this potentiality and mitigate tendencies toward greater false positives.

Clinical Quality Improvement Curriculum for Faculty in an Academic Medical Center.

Interested faculty enrolled in this 6-month-long quality improvement (QI) course to facilitate independent QI project work. The course included monthly 1.5-hour sessions: 20-minute presentations covering key QI concepts, then small group activities to facilitate project work. Faculty were required to identify, construct, and implement an independent QI project. They met individually with mentors twice during the course, with additional guidance offered virtually via phone or e-mail, and completed pretests and posttests of QI knowledge (maximum score = 15) and self-assessed confidence. A statistically significant difference in knowledge (pre-course mean = 7.75, standard deviation [SD] = 3.06; post-course mean = 11.75, SD = 3.28; P = .02) and self-assessed confidence (pre mean = 3.08, SD = 0.65; post mean = 4.5, SD = 0.68; P < .0001) was found. Of 8 faculty, 5 were able to conduct small tests of change; 3 studied the current processes and planned to run tests of change. Positive responses to this course helped obtain buy-in from leadership to develop a leadership program in QI.

Can Tablet Computers Enhance Faculty Teaching?

BACKGROUND: Learner benefits of tablet computer use have been demonstrated, yet there is little evidence regarding faculty tablet use for teaching. OBJECTIVE: Our study sought to determine if supplying faculty with tablet computers and peer mentoring provided benefits to learners and faculty beyond that of non-tablet-based teaching modalities. METHODS: We provided faculty with tablet computers and three 2-hour peer-mentoring workshops on tablet-based teaching. Faculty used tablets to teach, in addition to their current, non-tablet-based methods. Presurveys, postsurveys, and monthly faculty surveys assessed feasibility, utilization, and comparisons to current modalities. Learner surveys assessed perceived effectiveness and comparisons to current modalities. All feedback received from open-ended questions was reviewed by the authors and organized into categories. RESULTS: Of 15 eligible faculty, 14 participated. Each participant attended at least 2 of the 3 workshops, with 10 to 12 participants at each workshop. All participants found the workshops useful, and reported that the new tablet-based teaching modality added value beyond that of current teaching methods. Respondents developed the following tablet-based outputs: presentations, photo galleries, evaluation tools, and online modules. Of the outputs, 60% were used in the ambulatory clinics, 33% in intensive care unit bedside teaching rounds, and 7% in inpatient medical unit bedside teaching rounds. Learners reported that common benefits of tablet computers were: improved access/convenience (41%), improved interactive learning (38%), and improved bedside teaching and patient care (13%). A common barrier faculty identified was inconsistent wireless access (14%), while no barriers were identified by the majority of learners. CONCLUSIONS: Providing faculty with tablet computers and having peer-mentoring workshops to discuss their use was feasible and added value.

Outcomes of benign breast papillomas diagnosed at image-guided vacuum-assisted core needle biopsy.

PURPOSE: To determine the upgrade rate of benign papillomas diagnosed at image-guided vacuum-assisted core needle biopsy (VACNB) and to compare our results with the summarized literature. MATERIALS AND METHODS: A database search was performed to identify patients older than 18 years of age with benign papillomas diagnosed at VACNB between 2004 and 2013. A total of 199 papillomas in 184 patients were identified. Clinical, imaging, and pathological features for each were analyzed. Patients who were subsequently diagnosed with malignancy at the site of papilloma, either at surgical excision or upon imaging follow-up, were compared with those not upgraded. Upgrade was defined as a diagnosis of invasive carcinoma or ductal carcinoma in situ (DCIS). RESULTS: Of 199 papillomas, 110 (55.3%) were diagnosed at ultrasound-guided VACNB, 78 (39.2%) were diagnosed at stereotactic-guided VACNB, and 11 (5.5%) were diagnosed at magnetic resonance imaging-guided VACNB. Surgical excision was performed for 89 (44.7%), and the remaining 110 (55.3%) underwent imaging follow-up. Two patients were subsequently diagnosed with invasive carcinoma and 4 were found with DCIS. The upgrade rate across both groups was 3% (6 of 199). Masses with calcifications (P=.001) and smaller needle gauge at VACNB (P=.02) had a significant association with upgrade. CONCLUSION: Benign papillomas diagnosed with VACNB demonstrated a 3% upgrade rate to malignancy, which is similar to the 2.9% upgrade rate calculated by compiling applicable published literature. Conservative management with imaging follow-up as opposed to surgical excision may be appropriate in cases where an initial diagnosis of benign papilloma is made with VACNB. Benign papillomas associated with calcifications on imaging should be considered for surgical excision given their increased association with malignancy.

Expert panel consensus on assessment checklists for a rheumatology objective structured clinical examination.

OBJECTIVE: While several regional fellowship groups conduct rheumatology objective structured clinical examinations (ROSCEs), none have been validated for use across programs. We aimed to establish agreement among subspecialty experts regarding checklist items for several ROSCE stations. METHODS: We administered a 1-round survey to assess the importance of 173 assessment checklist items for 11 possible ROSCE stations. We e-mailed the survey to 127 rheumatology educators from across the US. Participants rated each item's importance on a 5-point Likert scale (1 = not important to 5 = very important). Consensus for high importance was predefined as a lower bound of the 95% confidence interval ≥4.0. RESULTS: Twenty-five individuals (20%) completed the expert panel survey. A total of 133 of the 173 items (77%) met statistical cutoff for consensus to retain. Several items that had population means of ≥4.0 but did not meet the predetermined definition for consensus were rejected. The percentage of retained items for individual stations ranged from 24% to 100%; all items were retained for core elements of patient counseling and radiograph interpretation tasks. Only 24% of items were retained for a rehabilitation medicine station and 60% for a microscope use/synovial fluid analysis station. CONCLUSION: This single-round expert panel survey established consensus on 133 items to assess on 11 proposed ROSCE stations. The method used in this study, which can engage a diverse geographic representation and employs rigorous statistical methods to establish checklist content agreement, can be used in any medical field.

Development and assessment of a web-based clinical quality improvement curriculum.

BACKGROUND: Understanding quality improvement (QI) is an important skill for physicians, yet educational interventions focused on teaching QI to residents are relatively rare. Web-based training may be an effective teaching tool in time-limited and expertise-limited settings. INTERVENTION: We developed a web-based curriculum in QI and evaluated its effectiveness. METHODS: During the 2011-2012 academic year, we enrolled 53 first-year internal medicine residents to complete the online training. Residents were provided an average of 6 hours of protected time during a 1-month geriatrics rotation to sequentially complete 8 online modules on QI. A pre-post design was used to measure changes in knowledge of the QI principles and self-assessed competence in the objectives of the course. RESULTS: Of the residents, 72% percent (37 of 51) completed all of the modules and pretests and posttests. Immediate pre-post knowledge improved from 6 to 8.5 for a total score of 15 (P < .001) and pre-post self-assessed competence in QI principles on paired t test analysis improved from 1.7 to 2.7 on a scale of 5 for residents who completed all of the components of the course. CONCLUSIONS: Web-based training of QI in this study was comparable to other existing non-web-based curricula in improving learner confidence and knowledge in QI principles. Web-based training can be an efficient and effective mode of content delivery.

Effect of automated bio-behavioral feedback on the control of type 1 diabetes.

OBJECTIVE: To test the effect of an automated system providing real-time estimates of HbA(1c), glucose variability, and risk for hypoglycemia. RESEARCH DESIGN AND METHODS: For 1 year, 120 adults with type 1 diabetes (69 female/51 male, age = 39.1 [14.3] years, duration of diabetes 20.3 [12.9] years, HbA(1c) = 8.0 [1.5]), performed self-monitoring of blood glucose (SMBG) and received feedback at three increasingly complex levels, each continuing for 3 months: level 1--routine SMBG; level 2--adding estimated HbA(1c), hypoglycemia risk, and glucose variability; and level 3--adding estimates of symptoms potentially related to hypoglycemia. The subjects were randomized to feedback sequences of either levels 1-2-3 or levels 2-3-1. HbA(1c), symptomatic hypoglycemia, and blood glucose awareness were evaluated at baseline and at the end of each level. RESULTS: For all subjects, HbA(1c) was reduced from 8.0 to 7.6 from baseline to the end of study (P = 0.001). This effect was confined to subjects with baseline HbA(1c) >8.0 (from 9.3 to 8.5, P < 0.001). Incidence of symptomatic moderate/severe hypoglycemia was reduced from 5.72 to 3.74 episodes/person/month (P = 0.019), more prominently for subjects with a history of severe hypoglycemia (from 7.20 to 4.00 episodes, P = 0.008) and for those who were hypoglycemia unaware (from 6.44 to 3.71 episodes, P = 0.045). The subjects' ratings of the feedback were positive, with up to 89% approval of the provided features. CONCLUSIONS: Feedback of SMBG data and summary SMBG-based measures resulted in improvement in average glycemic control and reduction in moderate/severe hypoglycemia. These effects were most prominent in subjects who were at highest risk at the baseline.