Douglas W. Roblin

The use of computed tomography in pediatrics and the associated radiation exposure and estimated cancer risk

IMPORTANCE Increased use of computed tomography (CT) in pediatrics raises concerns about cancer risk from exposure to ionizing radiation. OBJECTIVES To quantify trends in the use of CT in pediatrics and the associated radiation exposure and cancer risk. DESIGN Retrospective observational study. SETTING Seven US health care systems. PARTICIPANTS The use of CT was evaluated for children younger than 15 years of age from 1996 to 2010, including 4 857 736 child-years of observation. Radiation doses were calculated for 744 CT scans performed between 2001 and 2011. MAIN OUTCOMES AND MEASURES Rates of CT use, organ and effective doses, and projected lifetime attributable risks of cancer. RESULTS The use of CT doubled for children younger than 5 years of age and tripled for children 5 to 14 years of age between 1996 and 2005, remained stable between 2006 and 2007, and then began to decline. Effective doses varied from 0.03 to 69.2 mSv per scan. An effective dose of 20 mSv or higher was delivered by 14% to 25% of abdomen/pelvis scans, 6% to 14% of spine scans, and 3% to 8% of chest scans. Projected lifetime attributable risks of solid cancer were higher for younger patients and girls than for older patients and boys, and they were also higher for patients who underwent CT scans of the abdomen/pelvis or spine than for patients who underwent other types of CT scans. For girls, a radiation-induced solid cancer is projected to result from every 300 to 390 abdomen/pelvis scans, 330 to 480 chest scans, and 270 to 800 spine scans, depending on age. The risk of leukemia was highest from head scans for children younger than 5 years of age at a rate of 1.9 cases per 10 000 CT scans. Nationally, 4 million pediatric CT scans of the head, abdomen/pelvis, chest, or spine performed each year are projected to cause 4870 future cancers. Reducing the highest 25% of doses to the median might prevent 43% of these cancers. CONCLUSIONS AND RELEVANCE The increased use of CT in pediatrics, combined with the wide variability in radiation doses, has resulted in many children receiving a high-dose examination. Dose-reduction strategies targeted to the highest quartile of doses could dramatically reduce the number of radiation-induced cancers.

Use of diagnostic imaging studies and associated radiation exposure for patients enrolled in large integrated health care systems, 1996-2010

CONTEXT Use of diagnostic imaging has increased significantly within fee-for-service models of care. Little is known about patterns of imaging among members of integrated health care systems. OBJECTIVE To estimate trends in imaging utilization and associated radiation exposure among members of integrated health care systems. DESIGN, SETTING, AND PARTICIPANTS Retrospective analysis of electronic records of members of 6 large integrated health systems from different regions of the United States. Review of medical records allowed direct estimation of radiation exposure from selected tests. Between 1 million and 2 million member-patients were included each year from 1996 to 2010. MAIN OUTCOME MEASURE Advanced diagnostic imaging rates and cumulative annual radiation exposure from medical imaging. RESULTS During the 15-year study period, enrollees underwent a total of 30.9 million imaging examinations (25.8 million person-years), reflecting 1.18 tests (95% CI, 1.17-1.19) per person per year, of which 35% were for advanced diagnostic imaging (computed tomography [CT], magnetic resonance imaging [MRI], nuclear medicine, and ultrasound). Use of advanced diagnostic imaging increased from 1996 to 2010; CT examinations increased from 52 per 1000 enrollees in 1996 to 149 per 1000 in 2010, 7.8% annual increase (95% CI, 5.8%-9.8%); MRI use increased from 17 to 65 per 1000 enrollees, 10% annual growth (95% CI, 3.3%-16.5%); and ultrasound rates increased from 134 to 230 per 1000 enrollees, 3.9% annual growth (95% CI, 3.0%-4.9%). Although nuclear medicine use decreased from 32 to 21 per 1000 enrollees, 3% annual decline (95% CI, 7.7% decline to 1.3% increase), PET imaging rates increased after 2004 from 0.24 to 3.6 per 1000 enrollees, 57% annual growth. Although imaging use increased within all health systems, the adoption of different modalities for anatomic area assessment varied. Increased use of CT between 1996 and 2010 resulted in increased radiation exposure for enrollees, with a doubling in the mean per capita effective dose (1.2 mSv vs 2.3 mSv) and the proportion of enrollees who received high (>20-50 mSv) exposure (1.2% vs 2.5%) and very high (>50 mSv) annual radiation exposure (0.6% vs 1.4%). By 2010, 6.8% of enrollees who underwent imaging received high annual radiation exposure (>20-50 mSv) and 3.9% received very high annual exposure (>50 mSv). CONCLUSION Within integrated health care systems, there was a large increase in the rate of advanced diagnostic imaging and associated radiation exposure between 1996 and 2010.

The Cost-Effectiveness of Birth-Cohort Screening for Hepatitis C Antibody in U.S. Primary Care Settings

BACKGROUND In the United States, hepatitis C virus (HCV) infection is most prevalent among adults born from 1945 through 1965, and approximately 50% to 75% of infected adults are unaware of their infection. OBJECTIVE To estimate the cost-effectiveness of birth-cohort screening. DESIGN Cost-effectiveness simulation. DATA SOURCES National Health and Nutrition Examination Survey, U.S. Census, Medicare reimbursement schedule, and published sources. TARGET POPULATION Adults born from 1945 through 1965 with 1 or more visits to a primary care provider annually. TIME HORIZON Lifetime. PERSPECTIVE Societal, health care. INTERVENTION One-time antibody test of 1945-1965 birth cohort. OUTCOME MEASURES Numbers of cases that were identified and treated and that achieved a sustained viral response; liver disease and death from HCV; medical and productivity costs; quality-adjusted life-years (QALYs); incremental cost-effectiveness ratio (ICER). RESULTS OF BASE-CASE ANALYSIS Compared with the status quo, birth-cohort screening identified 808,580 additional cases of chronic HCV infection at a screening cost of

Disparities in Use of a Personal Health Record in a Managed Care Organization

2874 per case identified. Assuming that birth-cohort screening was followed by pegylated interferon and ribavirin (PEG-IFN+R) for treated patients, screening increased QALYs by 348,800 and costs by

Medication Errors Among Adults and Children With Cancer in the Outpatient Setting

5.5 billion, for an ICER of

Patient Satisfaction With Primary Care: Does Type of Practitioner Matter?

15,700 per QALY gained. Assuming that birth-cohort screening was followed by direct-acting antiviral plus PEG-IFN+R treatment for treated patients, screening increased QALYs by 532,200 and costs by

Sex differences in gout epidemiology, evaluation and treatment

19.0 billion, for an ICER of

Translating primary care practice climate into patient activation: the role of patient trust in physician.

35,700 per QALY saved. RESULTS OF SENSITIVITY ANALYSIS The ICER of birth-cohort screening was most sensitive to sustained viral response of antiviral therapy, the cost of therapy, the discount rate, and the QALY losses assigned to disease states. LIMITATION Empirical data on screening and direct-acting antiviral treatment in real-world clinical settings are scarce. CONCLUSION Birth-cohort screening for HCV in primary care settings was cost-effective. PRIMARY FUNDING SOURCE Division of Viral Hepatitis, Centers for Disease Control and Prevention.

Effect of increased cost-sharing on oral hypoglycemic use in five managed care organizations : How much is too much?

OBJECTIVE Personal health records (PHRs) can increase patient access to health care information. However, use of PHRs may be unequal by race/ethnicity. DESIGN The authors conducted a 2-year cohort study (2005-2007) assessing differences in rates of registration with KP.org, a component of the Kaiser Permanente electronic health record (EHR). MEASUREMENTS At baseline, 1,777 25-59 year old Kaiser Permanente Georgia enrollees, who had not registered with KP.org, responded to a mixed mode (written or Internet) survey. Baseline, EHR, and KP.org data were linked. Time to KP.org registration by race from 10/1/05 (with censoring for disenrollment from Kaiser Permanente) was adjusted for baseline education, comorbidity, patient activation, and completion of the baseline survey online vs. by paper using Cox proportional hazards. RESULTS Of 1,777, 34.7% (616) registered with KP.org between Oct 2005 and Nov 2007. Median time to registering a KP.org account was 409 days. Among African Americans, 30.1% registered, compared with 41.7% of whites (p < 0.01). In the hazards model, African Americans were again less likely to register than whites (hazard ratio [HR] = 0.652, 95% CI: 0.549-0.776) despite adjustment. Those with baseline Internet access were more likely to register (HR = 1.629, 95% CI: 1.294-2.050), and a significant educational gradient was also observed (more likely registration with higher educational levels). CONCLUSIONS Differences in education, income, and Internet access did not account for the disparities in PHR registration by race. In the short-term, attempts to improve patient access to health care with PHRs may not ameliorate prevailing disparities between African Americans and whites.

Construction of a Multisite DataLink Using Electronic Health Records for the Identification, Surveillance, Prevention, and Management of Diabetes Mellitus: The SUPREME-DM Project

PURPOSE Outpatients with cancer receive complicated medication regimens in the clinic and home. Medication errors in this setting are not well described. We aimed to determine rates and types of medication errors and systems factors associated with error in outpatients with cancer. METHODS We retrospectively reviewed records from visits to three adult and one pediatric oncology clinic in the Southeast, Southwest, Northeast, and Northwest for medication errors using established methods. Two physicians independently judged whether an error occurred (kappa = 0.65), identified its severity (kappa = 0.76), and listed possible interventions. RESULTS Of 1,262 adult patient visits involving 10,995 medications, 7.1% (n = 90; 95% CI, 5.7% to 8.6%) were associated with a medication error. Of 117 pediatric visits involving 913 medications, 18.8% (n = 22; 95% CI, 12.5% to 26.9%) were associated with a medication error. Among all visits, 64 of the 112 errors had the potential to cause harm, and 15 errors resulted in injury. There was a range in the rates of chemotherapy errors (0.3 to 5.8 per 100 visits) and home medication errors (0 to 14.5 per 100 visits in children) at different sites. Errors most commonly occurred in administration (56%). Administration errors were often due to confusion over two sets of orders, one written at diagnosis and another adjusted dose on the day of administration. Physician reviewers selected improved communication most often to prevent error. CONCLUSION Medication error rates are high among adult and pediatric outpatients with cancer. Our findings suggest some practical targets for intervention, including improved communication about medication administration in the clinic and home.