Candace D. McNaughton

High discordance of chest x-ray and computed tomography for detection of pulmonary opacities in ED patients: implications for diagnosing pneumonia ☆

OBJECTIVE To evaluate the diagnostic performance of chest x-ray (CXR) compared to computed tomography (CT) for detection of pulmonary opacities in adult emergency department (ED) patients. METHODS We conducted an observational cross-sectional study of adult patients presenting to 12 EDs in the United States from July 1, 2003, through November 30, 2006, who underwent both CXR and chest CT for routine clinical care. CXRs and CT scans performed on the same patient were matched. CXRs and CT scans were interpreted by attending radiologists and classified as containing pulmonary opacities if the final radiologist report noted opacity, infiltrate, consolidation, pneumonia, or bronchopneumonia. Using CT as a criterion standard, the diagnostic test characteristics of CXR to detect pulmonary opacities were calculated. RESULTS The study cohort included 3423 patients. Shortness of breath, chest pain and cough were the most common complaints, with 96.1% of subjects reporting at least one of these symptoms. Pulmonary opacities were visualized on 309 (9.0%) CXRs and 191 (5.6 %) CT scans. CXR test characteristics for detection of pulmonary opacities included: sensitivity 43.5% (95% CI, 36.4%-50.8%); specificity 93.0% (95% CI, 92.1%-93.9%); positive predictive value 26.9% (95% CI, 22.1%-32.2%); and negative predictive value 96.5% (95% CI, 95.8%-97.1%). CONCLUSION In this multicenter cohort of adult ED patients with acute cardiopulmonary symptoms, CXR demonstrated poor sensitivity and positive predictive value for detecting pulmonary opacities. Reliance on CXR to identify pneumonia may lead to significant rates of misdiagnosis.

Psychometric properties of the brief health literacy screen in clinical practice.

ABSTRACTBACKGROUNDThe three-item Brief Health Literacy Screen (BHLS) has been validated in research settings, but not in routine practice, administered by clinical personnel.OBJECTIVEAs part of the Health Literacy Screening (HEALS) study, we evaluated psychometric properties of the BHLS to validate its administration by clinical nurses in both clinic and hospital settings.PARTICIPANTSBeginning in October 2010, nurses in clinics and the hospital at an academic medical center have administered the BHLS during patient intake and recorded responses in the electronic health record.MEASURESTrained research assistants (RAs) administered the short Test of Functional Health Literacy in Adults (S-TOFHLA) and re-administered the BHLS to convenience samples of hospital and clinic patients. Analyses included tests of internal consistency reliability, inter-administrator reliability, and concurrent validity by comparing the nurse-administered versus RA-administered BHLS scores (BHLS-RN and BHLS-RA, respectively) to the S-TOFHLA.KEY RESULTSCronbach’s alpha for the BHLS-RN was 0.80 among hospital patients (N = 498) and 0.76 among clinic patients (N = 295), indicating high internal consistency reliability. Intraclass correlation between the BHLS-RN and BHLS-RA among clinic patients was 0.77 (95 % CI 0.71–0.82) and 0.49 (95 % CI 0.40–0.58) among hospital patients. BHLS-RN scores correlated significantly with BHLS-RA scores (r = 0.33 among hospital patients; r = 0.62 among clinic patients), and with S-TOFHLA scores (r = 0.35 among both hospital and clinic patients), providing evidence of inter-administrator reliability and concurrent validity. In regression models, BHLS-RN scores were significant predictors of S-TOFHLA scores after adjustment for age, education, gender, and race. Area under the receiver operating characteristic curve for BHLS-RN to predict adequate health literacy on the S-TOFHLA was 0.71 in the hospital and 0.76 in the clinic.CONCLUSIONSThe BHLS, administered by nurses during routine clinical care, demonstrates adequate reliability and validity to be used as a health literacy measure.

Short, Subjective Measures of Numeracy and General Health Literacy in an Adult Emergency Department

OBJECTIVES The objective was to evaluate the reliability and validity of brief subjective measures of numeracy and general health literacy in the adult emergency department (ED) setting. METHODS A convenience sample of adult ED patients completed subjective measures of general health literacy (Short Literacy Survey [SLS]) and numeracy (Subjective Numeracy Scale [SNS]). These patients also completed two objective tests of literacy (the Short Test of Functional Health Literacy in Adults [S-TOFHLA] and the Rapid Estimate of Adult Literacy in Medicine [REALM]) and an objective test of numeracy (Wide Range Achievement Test-4 [WRAT4]). Internal reliability of the subjective measures was assessed using Cronbachs alpha. Construct validity of the subjective measures was assessed by correlating them against the S-TOFHLA, REALM, and WRAT4, using Spearmans rank correlation coefficients, receiver operating characteristics (ROC) curves, and hierarchical, multiple linear regression with adjustment for patient age, sex, race, and education. RESULTS The median age of the 207 patients surveyed was 46 years (interquartile range [IQR] = 32 to 59 years); 27% were African American. Sixty-one percent of patients reported that their highest level of education was high school or below. As measured by the S-TOFHLA and REALM, most patients had adequate literacy levels (89% and 80%, respectively), while 44% of patients had below average numeracy skills on the WRAT4. The median SLS score was 14 (IQR = 12 to 15) on a scale of 3 to 15; the median SNS score was 36 (IQR = 30 to 42) on a scale of 6 to 48. The SLS and SNS had good internal reliability, with Cronbachs alphas of 0.74 and 0.82, respectively. The SLS Spearmans rank order correlation coefficient was 0.33 (95% confidence interval [CI] = 0.20 to 0.45) for the S-TOFHLA, with a standardized beta coefficient of 0.36 (p < 0.05) after adjustment for patient demographics. The SLS correlation coefficient was 0.26 (95% CI = 0.13 to 0.38) for the REALM, with a standardized beta coefficient of 0.38 (p < 0.05) after adjustment for patient demographics. The area under the ROC curve (AUC) for the SLS was 0.74 (95% CI = 0.68 to 0.80) when compared to the S-TOFHLA and 0.72 (95% CI = 0.65 to 0.78) when compared to the REALM. The SNS predicted numeracy well, with a correlation coefficient of 0.57 (95% CI = 0.47 to 0.65) for the WRAT4, a standardized beta coefficient of 0.30 (p < 0.05) after adjustment for patient demographics, and an AUC of 0.77 (95% CI = 0.70 to 0.82). CONCLUSIONS The SNS and SLS are reliable, valid tests that can be used to rapidly estimate general health literacy and numeracy skill levels in adult ED patients. Continuing work is needed to establish their ability to predict clinical outcomes.

Reducing Blood Culture Contamination in the Emergency Department: An Interrupted Time Series Quality Improvement Study

OBJECTIVES Blood culture contamination is a common problem in the emergency department (ED) that leads to unnecessary patient morbidity and health care costs. The study objective was to develop and evaluate the effectiveness of a quality improvement (QI) intervention for reducing blood culture contamination in an ED. METHODS The authors developed a QI intervention to reduce blood culture contamination in the ED and then evaluated its effectiveness in a prospective interrupted times series study. The QI intervention involved changing the technique of blood culture specimen collection from the traditional clean procedure to a new sterile procedure, with standardized use of sterile gloves and a new materials kit containing a 2% chlorhexidine skin antisepsis device, a sterile fenestrated drape, a sterile needle, and a procedural checklist. The intervention was implemented in a university-affiliated ED and its effect on blood culture contamination evaluated by comparing the biweekly percentages of blood cultures contaminated during a 48-week baseline period (clean technique) and 48-week intervention period (sterile technique), using segmented regression analysis with adjustment for secular trends and first-order autocorrelation. The goal was to achieve and maintain a contamination rate below 3%. RESULTS During the baseline period, 321 of 7,389 (4.3%) cultures were contaminated, compared to 111 of 6,590 (1.7%) during the intervention period (p < 0.001). In the segmented regression model, the intervention was associated with an immediate 2.9% (95% confidence interval [CI] = 2.2% to 3.2%) absolute reduction in contamination. The contamination rate was maintained below 3% during each biweekly interval throughout the intervention period. CONCLUSIONS A QI assessment of ED blood culture contamination led to development of a targeted intervention to convert the process of blood culture collection from a clean to a fully sterile procedure. Implementation of this intervention led to an immediate and sustained reduction of contamination in an ED with a high baseline contamination rate.

Predicting changes in hypertension control using electronic health records from a chronic disease management program

OBJECTIVE Common chronic diseases such as hypertension are costly and difficult to manage. Our ultimate goal is to use data from electronic health records to predict the risk and timing of deterioration in hypertension control. Towards this goal, this work predicts the transition points at which hypertension is brought into, as well as pushed out of, control. METHOD In a cohort of 1294 patients with hypertension enrolled in a chronic disease management program at the Vanderbilt University Medical Center, patients are modeled as an array of features derived from the clinical domain over time, which are distilled into a core set using an information gain criteria regarding their predictive performance. A model for transition point prediction was then computed using a random forest classifier. RESULTS The most predictive features for transitions in hypertension control status included hypertension assessment patterns, comorbid diagnoses, procedures and medication history. The final random forest model achieved a c-statistic of 0.836 (95% CI 0.830 to 0.842) and an accuracy of 0.773 (95% CI 0.766 to 0.780). CONCLUSIONS This study achieved accurate prediction of transition points of hypertension control status, an important first step in the long-term goal of developing personalized hypertension management plans.

Low Numeracy Is Associated With Increased Odds of 30-Day Emergency Department or Hospital Recidivism for Patients With Acute Heart Failure

Background— More than 25% of Medicare patients hospitalized for heart failure are readmitted within 30 days. The contributions of numeracy and health literacy to recidivism for patients with acute heart failure (AHF) are not known. Methods and Results— A cohort of patients with acute heart failure who presented to 4 emergency departments between January 2008 and September 2011. Research assistants administered subjective measures of numeracy and health literacy; 30-day follow-up was performed by phone interview. Recidivism was defined as any unplanned return to the emergency department or hospital within 30 days of the index emergency department visit for AHF. Multivariable logistic regression adjusting for patient age, sex, race, insurance status, hospital site, days eligible for recidivism, chronic kidney disease, abnormal hemoglobin, and low ejection fraction evaluated the relation between numeracy and health literacy with 30-day recidivism. Of the 709 patients included in the analysis, 390 (55%) had low numeracy skills and 258 (37%) had low literacy skills. Low numeracy was associated with increased odds of recidivism within 30 days (adjusted odds ratio, 1.41; 95% confidence interval, 1.00–1.98; P=0.048). For low health literacy, adjusted odds ratio of recidivism was 1.17 (95% confidence interval, 0.83–1.65; P=0.37). Conclusions— Low numeracy was associated with greater odds of 30-day recidivism. Further investigation is warranted to determine whether addressing numeracy and health literacy may reduce 30-day recidivism for patients with acute heart failure.

Health Literacy and Mortality: A Cohort Study of Patients Hospitalized for Acute Heart Failure

Background More than 30% of patients hospitalized for heart failure are rehospitalized or die within 90 days of discharge. Lower health literacy is associated with mortality among outpatients with chronic heart failure; little is known about this relationship after hospitalization for acute heart failure. Methods and Results Patients hospitalized for acute heart failure and discharged home between November 2010 and June 2013 were followed through December 31, 2013. Nurses administered the Brief Health Literacy Screen at admission; low health literacy was defined as Brief Health Literacy Screen ≤9. The primary outcome was all-cause mortality. Secondary outcomes were time to first rehospitalization and, separately, time to first emergency department visit within 90 days of discharge. Cox proportional hazards models determined their relationships with health literacy, adjusting for age, gender, race, insurance, education, comorbidity, and hospital length of stay. For the 1379 patients, average age was 63.1 years, 566 (41.0%) were female, and 324 (23.5%) had low health literacy. Median follow-up was 20.7 months (interquartile range 12.8 to 29.6 months), and 403 (29.2%) patients died. Adjusted hazard ratio for death among patients with low health literacy was 1.34 (95% CI 1.04, 1.73, P=0.02) compared to Brief Health Literacy Screen >9. Within 90 days of discharge, there were 415 (30.1%) rehospitalizations and 201 (14.6%) emergency department visits, with no evident association with health literacy. Conclusions Lower health literacy was associated with increased risk of death after hospitalization for acute heart failure. There was no evident relationship between health literacy and 90-day rehospitalization or emergency department visits.

Safe Prescribing: An Educational Intervention For Medical Students

Background and Purpose: Errors in handwritten medication orders are common and can result in patient harm. We evaluated an intervention for increasing safe prescribing by medical students. Methods: We conducted a pre-post evaluation to evaluate a brief educational intervention to increase safe prescribing by medical students. Two 1-hr, small-group, interactive educational sessions for 3rd-year medical students were held 2 weeks apart at Washington University in St. Louis. Prescribing errors were measured with a verbal transcription test. Results: Twenty-eight students participated. Following the intervention, the average number of error-free orders in the 10-order test increased 5-fold from 0.82 per student to 4.54 per student, and the average number of errors and dangerous errors per student decreased from 13.96 to 7.36 (p <. 0001) and from 4.75 to 2.68 (p <. 0001), respectively. Conclusions: After a brief interactive educational intervention for medical students, the frequency of error-free handwritten orders increased, and prescribing errors decreased. Additional training may be required to further improve and maintain safe prescribing.

Association of health literacy with elevated blood pressure: a cohort study of hospitalized patients.

Background:The clinical consequences of low health literacy are not fully understood. Objectives:We evaluated the relationship between low health literacy and elevated blood pressure (BP) at hospital presentation. Research Design and Subjects:We conducted a cross-sectional evaluation of adult patients hospitalized at a university hospital between November 1, 2010 and April 30, 2012. Measures:Health literacy was assessed using the Brief Health Literacy Screen (BHLS). Low health literacy was defined as a BHLS score ⩽9. BP was assessed using clinical measurements. The outcome was elevated BP (≥140/90 mm Hg; ≥130/80 mm Hg with diabetes or renal disease) or extremely elevated BP (>160/100 mm Hg) at hospital presentation. Multivariate logistic regression adjusted for age, sex, race, insurance, comorbidities, and antihypertensive medications; preplanned restricted analysis among patients with diagnosed hypertension was performed. Results:Of 46,263 hospitalizations, 23% had low health literacy, which occurred more often among patients who were older (61 vs. 54 y), less educated (28.4% vs. 11.2% had not completed high school), and more often admitted through the emergency department (54.3% vs. 48.1%) than those with BHLS>9. Elevated BP was more frequent among those with low health literacy [40.0% vs. 35.5%; adjusted odds ratio (aOR) 1.06; 95% confidence interval (CI), 1.01–1.12]. Low health literacy was associated with extremely elevated BP (aOR 1.08; 95% CI, 1.01–1.16) and elevated BP among those without diagnosed hypertension (aOR 1.09; 95% CI, 1.02–1.16). Conclusions:More than ⅓ of patients had elevated BP at hospital presentation. Low health literacy was independently associated with elevated BP, particularly among patients without diagnosed hypertension.

Low Literacy is associated with Uncontrolled Blood Pressure in Primary Care Patients with Hypertension and Heart Disease

OBJECTIVES To evaluate the association between low literacy and uncontrolled blood pressure (BP) and their associations with medication adherence. METHODS Cross-sectional study of 423 urban, primary care patients with hypertension and coronary disease. The relationship between low literacy (Rapid Estimate of Adult Literacy in Medicine ≤ 44) and uncontrolled BP (≥140/90 mmHg, ≥130/80 mmHg for patients with diabetes) was evaluated by crude and adjusted logistic regression. Relationships with self-reported adherence and refill adherence were explored using adjusted linear and logistic regression. RESULTS Overall, 192 (45%) subjects had low literacy and 227 (52.9%) had uncontrolled BP. Adjusting for age, gender, race, employment, education, mental status, and self-reported adherence, low literacy was associated with uncontrolled BP (OR 1.75, 95% CI 1.06-2.87). Lower self-reported adherence was associated with uncontrolled BP; the relationship between refill adherence and uncontrolled BP was not statistically significant. CONCLUSION Low literacy is independently associated with uncontrolled BP. PRACTICE IMPLICATIONS Awareness of the relationships among patient literacy, BP control, and medication adherence may guide healthcare providers as they communicate with patients.