Kombucha: a systematic review of the empirical evidence of human health benefit.

PURPOSE: Kombucha tea, a fermented beverage, has recently become popular in the United States as part of the functional food movement. This popularity is likely driven by its touted health benefits, coupled with the recent scientific movement investigating the role of the microbiome on human health. The purpose of this systematic review is to describe the literature related to empirical health benefits of kombucha as identified from human subjects research. METHODS: In July 2018, we searched the term "kombucha" for all document types in the following databases across all available years: PubMed, Scopus, and Ovid. To identify federal research grants related to kombucha, we searched the National Institutes of Health Research Portfolio Online Reporting Tools. Finally, to identify ongoing human subjects research, we searched clinicaltrials.gov and clinicaltrialsregister.eu. We reviewed a total of 310 articles. RESULTS: We found one study reporting the results of empirical research on kombucha in human subjects. We found no results for kombucha in Research Portfolio Online Reporting Tools, clinicaltrials.gov, or clinicaltrialsregister.eu. CONCLUSIONS: The nonhuman subjects literature claims numerous health benefits of kombucha; it is critical that these assertions are tested in human clinical trials. Research opportunities are discussed.

Quantifying Worry in the Face of Uncertainty: Radiation Exposure from Medical Imaging.

BACKGROUND: The degree to which people worry about radiation exposure from medical imaging has not been quantified. Such concern is important for clinical decision making and policy generation. OBJECTIVE: The aim of this study was to quantify the degree of worry as a consequence of radiation exposure. DESIGN: A time trade-off methodology was used to estimate health state utilities associated with radiation exposure from computed tomography scans in an inclusive sample of physicians. Health state utilities were elicited from in-person interviews using a software-guided, hypothetical scenario in which the subject is exposed to two separate computed tomography scans. RESULTS: One hundred and eighteen interviews were conducted. The overall mean and median utility values for the health state of concern due to radiation exposure were 0.95 (95% confidence interval: 0.94-0.96) and 0.98 (interquartile range: 0.91-1.00), respectively. The utility score distribution was highly skewed toward higher values. Five respondents (4.3%) recorded a utility score of ≤0.8 and 17 respondents (14.5%) were willing to sacrifice at least 5 or more years of life to live free of the radiation-exposure worry. CONCLUSIONS AND RELEVANCE: The physician respondents generally demonstrated low levels of disutility; however, a subset of physicians expressed much greater disutility for the future risk of malignancy. Given the potential for physicians to influence health care decisions and policies, further study of radiation-related concerns seems warranted. Physicians, patients, and the general public should be aware of the potential impact such differing views held by physicians may have on their clinical recommendations.

A randomized controlled trial of directive and nondirective smoking cessation coaching through an employee quitline.

BACKGROUND: Telephone quitlines can help employees quit smoking. Quitlines typically use directive coaching, but nondirective, flexible coaching is an alternative. Call-2-Quit used a worksite-sponsored quitline to compare directive and nondirective coaching modes, and evaluated employee race and income as potential moderators. METHODS: An unblinded randomized controlled trial compared directive and nondirective telephone coaching by trained laypersons. Participants were smoking employees and spouses recruited through workplace smoking cessation campaigns in a hospital system and affiliated medical school. Coaches were four non-medical women trained to use both coaching modes. Participants were randomized by family to coaching mode. Participants received up to 7 calls from coaches who used computer assisted telephone interview software to track topics and time. Outcomes were reported smoking abstinence for 7 days at last contact, 6 or 12 months after coaching began. Both worksites implemented new tobacco control policies during the study. RESULTS: Most participants responded to an insurance incentive introduced at the hospital. Call-2-Quit coached 518 participants: 22 % were African-American; 45 % had incomes below $30,000. Income, race, and intervention did not affect coaching completion rates. Cessation rates were comparable with directive and nondirective coaching (26 % versus 30 % quit, NS). A full factorial logistic regression model identified above median income (odds ratio = 1.8, p = 0.02), especially among African Americans (p = 0.04), and recent quit attempts (OR = 1.6, p = 0.03) as predictors of cessation. Nondirective coaching was associated with high cessation rates among subgroups of smokers reporting income above the median, recent quit attempts, or use of alternative therapies. Waiting up to 4 weeks to start coaching did not affect cessation. Of 41 highly addicted or depressed smokers who had never quit more than 30 days, none quit. CONCLUSION: Nondirective coaching improved cessation rates for selected smoking employees, but less expensive directive coaching helped most smokers equally well, regardless of enrollment incentives and delays in receiving coaching. Some subgroups had very low cessation rates with either mode of quitline support. TRIAL REGISTRATION: ClinicalTrials.gov NCT02730260 , Registered March 31, 2016.

Electronic cigarettes: The nicotyrine hypothesis.

There are conflicting reports about the efficacy of electronic cigarettes (e-cigs) as nicotine delivery devices and smoking cessation products. In addition, smokers' responses to some nicotine dependence questions often change as they transition to exclusive e-cig use. Nicotyrine may explain these observations. Nicotyrine forms by the gradual oxidation of nicotine in e-liquids exposed to air. E-cigs aerosolize nicotyrine along with nicotine. Nicotyrine inhibits the cytochrome P450 2A family of enzymes (CYP2A) in airways and liver. These enzymes metabolize nicotine to cotinine, and then cotinine to trans 3-hydroxycotinine. In humans, nicotine is metabolized primarily by hepatic CYP2A6. We propose that e-cig users (vapers) achieve measurable serum nicotine levels when they inhale nicotine and nicotyrine together, because nicotyrine reversibly inhibits nicotine metabolism by CYP2A13 in airways. Consuming nicotyrine by any route should irreversibly inhibit hepatic CYP2A6. When CYP2A6 is substantially inhibited, nicotine clearance is delayed and nicotine withdrawal symptoms are attenuated. Small, relatively infrequent nicotine doses can then sustain satisfying nicotine levels. This theory has numerous implications for e-cig research and tobacco control. Behavioral and pharmacokinetic e-cig studies should be interpreted with attention to likely levels of nicotyrine delivery: e-cig studies may need to routinely measure nicotyrine exposure, assess CYP2A6 activity, confirm nicotine delivery, or deliberately compare unoxidized and oxidized e-liquids. The risks of nicotyrine exposure include impaired clearance of all CYP2A substrates and any effects of the metabolic products of nicotyrine. CYP2A inhibitors like nicotyrine may be useful for future smoking cessation therapy.

On-Line Chemical Composition Analysis of Refillable Electronic Cigarette Aerosol-Measurement of Nicotine and Nicotyrine.

INTRODUCTION: Electronic cigarettes (e-cigs) generate aerosols that users inhale. Analyses of e-liquids inconsistently report nicotyrine, a nicotine analog that could impede nicotine metabolism, raising questions about nicotyrine formation. METHODS: E-cig aerosols were analyzed on-line using a Thermal Desorption Aerosol Gas Chromatograph. Three e-liquids were tested: an unflavored solution in propylene glycol (PG); an unflavored solution in PG and vegetable glycerin (VG), and a flavored solution in PG and VG. A heating duration experiment determined the nicotyrine to nicotine ratio (NNR) in particle phase as a function of the duration of e-cig activation. An aging experiment determined the NNR in e-liquids and aerosols as a function of time since initial exposure to air and storage condition. RESULTS: Nicotine and nicotyrine were quantified in all 3 e-liquids and aerosols. Duration of e-cig activation was inversely related to NNR (NNR = 0.04 with 3-s activation, 0.26 with 0.5 s). Aging influenced both e-liquid NNR and aerosol NNR. On average, the e-liquid NNR increased from 0.03 at 11 days after opening to 0.08 after 60 days. For similar heating durations, aerosol NNR increased from 0.05 at 11 days to 0.23 after 60 days. Storage conditions had little effect on NNR. CONCLUSIONS: E-cig aerosols have variable nicotyrine quantities. Aerosol NNR depends on vaping technique and time elapsed since the e-liquid was exposed to air. It is hypothesized that aerosolized nicotyrine could facilitate nicotine absorption, inhibit the metabolism of nicotine, and reduce a user's urge to smoke.

Analysis of comments in a petition defending electronic cigarettes.

INTRODUCTION: A 2009 petition opposing a Food and Drug Administration (FDA) ban on electronic cigarettes (e-cigs) garnered international attention from e-cig users (vapers). Petitioners' comments described the perceived benefits of vaping. METHODS: We conducted a qualitative and quantitative analysis of petitioners' comments. A sample of 200 petitioner names was sought in public records. Reviewers identified 13 major themes in a sample of comments, and themes related to current controversies were added. For each theme, software pattern-matching instructions (regular expressions) were developed and were used to scan comments. Agreement between reviewers and software was calculated; theme prevalence and clustering was ascertained. RESULTS: A total of 13,414 signatures and 8,285 comments from 50 states and 75 nations were collected in 6 months. Temporal patterns and name matches in public records suggest that most petitioners are authentic. Agreement between reviewers and software was moderate to high (κ = 0.4-0.8). Commonly cited themes were "e-cigs helped me quit" (34%), "a ban would be counterproductive" (15%), and "my health improved with e-cigs" (13%). Two clusters of themes emerged: the first combined comments about smoking cessation, health benefits, and smoking relapse that an e-cig ban would cause; the second combined themes that a "ban would be counterproductive," it would infringe on personal liberties, and it was motivated by government or industrial greed. People who cited mental health issues often mentioned avoiding withdrawal as a benefit of e-cigs. CONCLUSIONS: Early e-cig adopters were both frustrated and confused by discussion of a ban. They believed that e-cigs safely delivered nicotine and helped them quit smoking.

Beliefs, experience, and interest in pharmacotherapy among smokers with HIV.

OBJECTIVES: To examine beliefs, prior use, and interest in using pharmacotherapy among people living with HIV/AIDS (PLWHA). METHODS: Cross-sectional survey of smokers in a midwestern HIV clinic. RESULTS: The sample (N = 146) included 69% men, 82% African Americans, 45% were in precontemplation for quitting, and 46% were interested in using pharmacotherapy. Primary reasons for non-use included cost and a belief that they would be able to quit on their own. Physician assistance was the strongest correlate of prior use. Perceived benefits and self-efficacy were the strongest correlates of willingness to use pharmacotherapy. CONCLUSIONS: Future interventions should address misconceptions, perceived benefits, and self-efficacy for using cessation aids. Physicians should offer pharmacotherapy to all smokers.

Methods for Performing Survival Curve Quality-of-Life Assessments.

BACKGROUND: Many medical decisions involve an implied choice between alternative survival curves, typically with differing quality of life. Common preference assessment methods neglect this structure, creating some risk of distortions. METHODS: Survival curve quality-of-life assessments (SQLA) were developed from Gompertz survival curves fitting the general population's survival. An algorithm was developed to generate relative discount rate-utility (DRU) functions from a standard survival curve and health state and an equally attractive alternative curve and state. A least means squared distance algorithm was developed to describe how nearly 3 or more DRU functions intersect. These techniques were implemented in a program called X-Trade and tested. RESULTS: SQLA scenarios can portray realistic treatment choices. A side effect scenario portrays one prototypical choice, to extend life while experiencing some loss, such as an amputation. A risky treatment scenario portrays procedures with an initial mortality risk. A time trade scenario mimics conventional time tradeoffs. Each SQLA scenario yields DRU functions with distinctive shapes, such as sigmoid curves or vertical lines. One SQLA can imply a discount rate or utility if the other value is known and both values are temporally stable. Two SQLA exercises imply a unique discount rate and utility if the inferred DRU functions intersect. Three or more SQLA results can quantify uncertainty or inconsistency in discount rate and utility estimates. Pilot studies suggested that many subjects could learn to interpret survival curves and do SQLA. LIMITATIONS: SQLA confuse some people. Compared with SQLA, standard gambles quantify very low utilities more easily, and time tradeoffs are simpler for high utilities. When discount rates approach zero, time tradeoffs are as informative and easier to do than SQLA. CONCLUSIONS: SQLA may complement conventional utility assessment methods.

Rural, suburban, and urban differences in factors that impact physician adherence to clinical preventive service guidelines.

PURPOSE: Rural-urban disparities in provision of preventive services exist, but there is sparse research on how rural, suburban, or urban differences impact physician adherence to clinical preventive service guidelines. We aimed to identify factors that may cause differences in adherence to preventive service guidelines among rural, suburban, and urban primary care physicians. METHODS: This qualitative study involved in-depth semistructured interviews with 29 purposively sampled primary care physicians (10 rural, 10 suburban, 9 urban) in Missouri. Physicians were asked to describe barriers and facilitators to clinical preventive service guideline adherence. Using techniques from grounded theory analysis, 2 coders first independently conducted content analysis then reconciled differences in coding to ensure agreement on intended meaning of transcripts. FINDINGS: Patient epidemiologic differences, distance to health care services, and care coordination were reported as prominent factors that produced differences in preventive service guideline adherence among rural, suburban, and urban physicians. Epidemiologic differences impacted all physicians, but rural physicians highlighted the importance of occupational risk factors in their patients. Greater distance to health care services reduced visit frequency and was a prominent barrier for rural physicians. Care coordination among health care providers was problematic for suburban and urban physicians. Patient resistance to medical care and inadequate access to resources and specialists were identified as barriers by some rural physicians. CONCLUSIONS: The rural, suburban, or urban context impacts whether a physician will adhere to clinical preventive service guidelines. Efforts to increase guideline adherence should consider the barriers and facilitators unique to rural, suburban, or urban areas.

Adding flexible temporal constraints to identify chronic comorbid conditions in ambulatory claims data.

Chronic comorbid conditions are important predictors of primary care outcomes, provide context for clinical decisions, and are potential complications of diseases and treatments. Comorbidity indices and multimorbidity categorization strategies based on administrative claims data enumerate diagnostic codes in easily modifiable lists, but usually have inflexible temporal requirements, such as requiring two claims greater than 30 days apart, or three claims in three quarters. Table structures and claims data search algorithms were developed to support flexible temporal constraints. Tables of disease categories allow subgroups with different numbers of events, different times between similar claims, variable periods of interest, and specified diagnostic code substitutability. The strategy was tested on five years of private insurance claims from 2.2 million working age adults. The contrast between rarely recorded, high prevalence diagnoses (smoking and obesity) and frequently recorded but not necessarily chronic diagnoses (musculoskeletal complaints) demonstrated the advantage of flexible temporal criteria.

In vitro particle size distributions in electronic and conventional cigarette aerosols suggest comparable deposition patterns.

INTRODUCTION: Electronic cigarette users ("vapers") inhale aerosols of water, nicotine, and propylene glycol (PG) or vegetable glycerin (VG). Aerosol particle sizes should affect deposition patterns in vapers and bystanders. METHODS: Aerosols were generated by a smoking machine and an electronic cigarette filled with 16mg/ml nicotine in aqueous PG or VG solution. A scanning mobility particle sizer (SMPS) counted particles of 10-1,000 nm diameters. A single puff experiment counted particles immediately and after aging 10 and 40 s. A steady-state experiment counted particles emitted from a collection chamber, untreated and after desiccation or organic vapor removal. The International Commission on Radiological Protection (ICRP) human respiratory tract model was used to estimate deposition. Results were compared to similar data from reference cigarettes. RESULTS: Puffs generated peak particle counts at (VG) 180 nm and (PG) 120 nm. Steady-state peaks occurred around 400 nm. Organic vapor removal eliminated small particles and reduced the size and number of large particles. Desiccation reduced the total volume of particles by 70% (VG, small PG) to 88% (large PG). The ICRP model predicted 7%-18% alveolar delivery; 9%-19% venous delivery, mostly in the head; and 73%-80% losses by exhalation. Reference cigarettes generated more particles initially, but were otherwise similar; however, in vivo smoke particle deposition is higher than the model predicts. CONCLUSIONS: Nicotine delivery may depend on vaping technique, particle evolution, and cloud effects. Predicted 10% arterial and 15% venous delivery may describe bystander exposure better than vapers exposure.

Diuretic of choice in ABFM hypertension self-assessment module simulations.

BACKGROUND: Evidence suggests that chlorthalidone has therapeutic advantages over hydrochlorothiazide, perhaps because of a longer antihypertensive effect. Although guidelines such as the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure treat diuretics as a class, some experts believe chlorthalidone is the diuretic of choice in hypertension management. We evaluated diplomates' use of chlorthalidone and hydrochlorothiazide as first-choice diuretics in virtual patient simulations of hypertension in the American Board of Family Medicine Maintenance of Certification for Family Physicians self-assessment modules. METHODS: We examined action logs for hypertension simulations completed between 2004 and 2011 and identified initial antihypertensive choices made by diplomates. We tabulated uses of any diuretic as initial treatment, distinguishing between chlorthalidone, hydrochlorothiazide, and other diuretic choices. We examined trends in the use of diuretics and chlorthalidone in simulations using linear models. RESULTS: Chlorthalidone use increased 0.7 percentage points per year (test for ß >0, P < .0013), from approximately 1.3% of simulation prescriptions in 2004 to about 4.8% in 2010 and 2011, whereas hydrochlorothiazide prescriptions fell 2 percentage points per year (P = .035), from nearly 57% to 47%. As a fraction of all diuretic use, chlorthalidone increased 1.4 percentage points per year (P = .0006), from 2% to 9%. CONCLUSIONS: Small but growing numbers of diplomates are heeding recommendations in the growing literature to start with chlorthalidone rather than hydrochlorothiazide, at least in the virtual patient environment. Observed choices in virtual patient management strongly imply that this is a valid topic for additional attention in the hypertension self-assessment module.

Family physicians' completion of scoring criteria in Virtual Patient encounters.

The American Board of Family Medicine (ABFM) has used a 60-item Multiple Choice Question (MCQ) section followed by a Virtual Patient (VP) exercise in Maintenance Of Certification (MOC) since 2004, and has had an asthma module since 2005. The original asthma VP criteria anticipated some Expert Panel Report-3 recommendations, such as home peak flow monitoring and a written plan, that were added to the MCQ section only when the guideline was updated in 2007. VP completion rates for these criteria improved markedly with the MCQ update, while other criteria completion rates were stable. Asthma criteria completion rates are not predicted by the strength of evidence for the criteria. User interface details influence criteria completion rates, but did not affect the changes observed in 2007. Asthma MCQ content affects Diplomate performance on asthma VP: this translational step suggests that MOC exercises could result in improved care for real patients.

Variation over time in preventable hospitalization rates across counties.

BACKGROUND: The Agency for Health Care Research and Quality developed 14 prevention quality indicators (PQIs), including four PQIs related to preventable hospitalizations for diabetes and one to asthma. Quality indicators vary across counties, but variation over time has not been described. METHODS: The Kentucky Cabinet for Health and Family Services published PQI data for each county in Kentucky in each of the 3 years from 2006 to 2008. Variation and correlations among PQI measures were calculated. RESULTS: PQI rates often varied 10-fold between counties. Repeated measures of four PQIs were highly correlated, suggesting local health care processes that are stable over time. Some PQIs, such as PQI01--emergent complications of blood glucose control--correlated poorly with other measures. Other PQIs are correlated over geography and time, including PQI03 (long-term complications of diabetes); PQI14 (poorly controlled diabetes); and PQI15 (asthma). CONCLUSIONS: These county PQI measures were stable over time. Stability implies that PQI measures were not the result of random processes and did not rapidly shift. However, some health improvement needs varied between counties. Although tailoring health promotion interventions to each county's needs may be complex, stable needs afford time to undertake targeted quality improvement efforts.

Interviews with "vapers": implications for future research with electronic cigarettes.

INTRODUCTION: Awareness and use of electronic cigarettes (e-cigs) has increased dramatically. Electronic Nicotine Delivery Devices deliver an aerosol comprised usually of water, propylene glycol and/or glycerin, nicotine, and flavorings. Scant research exists to evaluate the efficacy and safety of such devices, and only one quantitative survey of European users (N = 81) has been published. This qualitative study explores e-cig users' ("vapers") experiences. METHODS: Participants attended a convention or club meeting in St. Louis, MO, and were interviewed individually or in small groups. Qualitative methods were used to analyze interview data for both deductive and emergent themes to broad research questions. RESULTS: Even with a relatively small sample of formal participants (N = 15), there were pervasive themes including the language and culture of vaping; social and informational support among vapers and their use of Internet resources (learning about e-cigs); the learning curve to using e-cigs and the numerous modifications ("mods") available for e-cigs and personal vaporizers; motives and perceived benefits of using e-cigs versus cigarettes including cigarette-like enjoyment, cost, restored sense of taste and smell, and improved breathing and exercise tolerance; rapidly reduced nicotine tolerance and dependence; and a strong interest in e-cig-related research and policy. CONCLUSIONS: The learning curve to using e-cigs has important implications for laboratory tests of these devices with novice users. Similarly, the multiple e-cig options and the use of "mods" create challenges for researchers and policy makers. Transdisciplinary research is urgently needed, and experienced "vapers" are very interested and willing research participants.

Health and life insurance as an alternative to malpractice tort law.

BACKGROUND: Tort law has legitimate social purposes of deterrence, punishment and compensation, but medical tort law does none of these well. Tort law could be counterproductive in medicine, encouraging costly defensive practices that harm some patients, restricting access to care in some settings and discouraging innovation. DISCUSSION: Patients might be better served by purchasing combined health and life insurance policies and waiving their right to pursue malpractice claims. The combined policy should encourage the insurer to profit by inexpensively delaying policyholders' deaths. A health and life insurer would attempt to minimize mortal risks to policyholders from any cause, including medical mistakes and could therefore pursue systematic quality improvement efforts. If policyholders trust the insurer to seek, develop and reward genuinely effective care; identify, deter and remediate poor care; and compensate survivors through the no-fault process of paying life insurance benefits, then tort law is largely redundant and the right to sue may be waived. If expensive defensive medicine can be avoided, that savings alone could pay for fairly large life insurance policies. SUMMARY: Insurers are maligned largely because of their logical response to incentives that are misaligned with the interests of patients and physicians in the United States. Patient, provider and insurer incentives could be realigned by combining health and life insurance, allowing the insurer to use its considerable information access and analytic power to improve patient care. This arrangement would address the social goals of malpractice torts, so that policyholders could rationally waive their right to sue.

Area-level poverty is associated with greater risk of ambulatory-care-sensitive hospitalizations in older breast cancer survivors.

OBJECTIVES: To estimate the frequency of ambulatory care-sensitive hospitalizations (ACSHs) and to compare the risk of ACSH in breast cancer survivors living in high-poverty with that of those in low-poverty areas. DESIGN: Prospective, multilevel study. SETTING: National, population-based 1991 to 1999 National Cancer Institute Surveillance, Epidemiology, and End Results Program data linked with Medicare claims data throughout the United States. PARTICIPANTS: Breast cancer survivors aged 66 and older. MEASUREMENTS: ACSH was classified according to diagnosis at hospitalization. The percentage of the population living below the U.S. federal poverty line was calculated at the census-tract level. Potential confounders included demographic characteristics, comorbidity, tumor and treatment factors, and availability of medical care. RESULTS: Of 47,643 women, 13.3% had at least one ACSH. Women who lived in high-poverty census tracts (>or=30% poverty rate) were 1.5 times (95% confidence interval (CI)=1.34-1.72) as likely to have at least one ACSH after diagnosis as women who lived in low-poverty census tracts (<10% poverty rate). After adjusting for most confounders, results remained unchanged. After adjustment for comorbidity, the hazard ratio (HR) was reduced to 1.34 (95% CI=1.18-1.52), but adjusting for all variables did not further reduce the risk of ACSH associated with poverty rate beyond adjustment for comorbidity (HR=1.37, 95% CI=1.19-1.58). CONCLUSION: Elderly breast cancer survivors who lived in high-poverty census tracts may be at increased risk of reduced posttreatment follow-up care, preventive care, or symptom management as a result of not having adequate, timely, and high-quality ambulatory primary care as suggested by ACSH.

Using county-level public health data to prioritize medical education topics.

INTRODUCTION: Medical education topics might be locally prioritized using public health data on health outcomes and risk factors unrelated to quality of care. METHODS: The Missouri Information for Community Assessment (MICA) supplied preventable hospitalization rates (PHRs) for asthma, chronic obstructive pulmonary disease (COPD), diabetes, heart failure, and hypertension in 114 counties from 1998 to 2002. For each disease, a linear regression model predicted PHR from behavior, access, and disease prevalence data from MICA and other public data sources. For each disease in each county, the residual, unexplained PHR should include effects of local medical practices. Variation in relative priority of diseases between counties was estimated from raw PHR and unexplained PHR. RESULTS: The raw values of the five PHRs varied geographically in different patterns. Regression models explained between 46% and 83% of the variability. The medical education priorities implied by unexplained PHR values differ from priorities inferred from unadjusted PHR or disease prevalence. DISCUSSION: Patient behavior and poor health care access contribute to PHR but do not fully explain variation in PHR. If county-level unexplained PHR values identify high priority medical education topics, then other measures of importance, notably disease prevalence and PHR, are poor identifiers of high value topics. Although available predictor and outcome variables constrain the current analysis, unexplained variation in health outcome measures might identify educational opportunities. These observations suggest strategies for balancing and evaluating controlled trials of knowledge dissemination efforts and eventually for deploying educational activities.

Value of information in virtual patient performance evaluations.

The American Board of Family Medicine (ABFM) uses virtual patients (VP) in Maintenance of Certification. User queries might be evaluated by calculating diagnostic value of information (VOI). Typical primary care queries address concerns far beyond efficient diagnosis. We identify practical constraints on VOI scoring in simulations of primary care practice. We imagine a Bayesian physician as the ideal candidate for VOI scoring. Bayesian physicians require an explicit decision making perspective and many local data.