Donald R. Holleman

Diagnosis of obstructive airways disease from the clinical examination

AbstractObjective: To determine the operating characteristics of history and physical examination items for pulmonary airflow obstruction. Design: Prospective observational study. Setting: Medical Preoperative Evaluation Clinic at the Durham Veterans Affairs Medical Center. Patients/participants: Consecutive patients referred for outpatient medical preoperative risk assessment. Interventions: None. Measurements and main results: Number of years the patient had smoked cigarettes, patient-reported wheezing [LR+ (likelihood ratio for finding present)=3.1; LR− (likelihood ratio for finding absent)=0.58], and auscultated wheezing (LR+=12; LR−=0.87) were independent predictors of obstructive airways disease from the history and physical examination. Forced expiratory time and peak expiratory flow rate, both measured by the clinician at the bedside, were additional independent predictors of airflow obstruction. A nomogram using patient-reported wheezing, number of years the patient had smoked, and auscultated wheezing was developed and validated (area under receiver operating characteristic curve=0.78; p=0.0001) for the bedside prediction of obstructive airways disease. Peak expiratory flow rate can be substituted for auscultated wheezing with similar predictive ability. Conclusions: The results of bedside clinical examinations predict the presence of obstructive airways disease. A nomogram based on a combination of four bedside findings predicts airflow obstruction as well as clinicians’ overall clinical impressions.

Predicting daily visits to a walk-in clinic and emergency department using calendar and weather data.

We studied the association between calendar and weather variables and daily unscheduled patient volume in a walk-in clinic and emergency department. Calendar variables (season, week of month, day of week, holidays, and federal check delivery days) and weather variables (high temperature and snowfall) forecasted clinic volume, explaining 84% of daily variance and 44% of weekday variance. Staffing according to predicted volume could have decreased overstaffing from 59%to 15% of days, but would have increased under-staffing from 2% to 18% of days. Models using calendar and weather data that forecast local utilization may help to schedule staffing for walk-in clinics and emergency departments more efficiently.

Quantitative Assessments from the Clinical Examination

OBJECTIVE: To describe strategies for using multiple clinical examination items to estimate disease probabilities; and to evaluate the diagnostic accuracy of each strategy. DESIGN: Prospective observational study. SETTING: Medical preoperative evaluation clinic at a university-affiliated Veterans Affairs Medical Center. PATIENTS: Previously reported consecutive series of patients referred for outpatient medical preoperative risk assessment. MEASUREMENTS AND MAIN RESULTS: Pulmonary clinical examination and spirometry were the measurements. A strategy of using likelihood ratios (LRs) from seven clinical examination items was least accurate (p < .0001). Three alternative strategies were equivalent in diagnostic accuracy (p≥ .2): (1) using the single best clinical examination item and its LR, (2) using the LRs from three clinical examination items chosen by logistic regression, and (3) using the adjusted LRs chosen in strategy 2. When compared with using LRs from all seven items, the strategies of using three LRs chosen by logistic regression or using adjusted likelihood ratios better discriminated patients with airflow limitation from those without (receiver operating characteristic [ROC] areas 0.79 vs 0.69;p= .02). Using the single best clinical finding did not statistically degrade the clinical examination’s discriminating ability (ROC areas 0.79 vs 0.75;p= .20). CONCLUSIONS: Describing the rational clinical examination requires evaluating conditional independence of examination components. Conditional independence assumptions were violated when seven clinical examination items were used to estimate posterior probability of airflow limitation. Focusing on clinical examination items identified through logistic models overcame violations of independence; further statistical adjustment did not improve diagnostic accuracy. Clinicians can use the single most predictive clinical examination finding to avoid inaccuracy from violating the independence assumption.

Resident recognition of open-angle glaucoma: effects of an educational intervention

To test an educational intervention’s effect on improving detection of glaucoma by direct ophthalmoscopy, 14 medicine residents examined five patients, two with ophthalmoscopic changes of glaucoma and three with normal fundi. The residents observed a standardized slide/narrative educational intervention reviewing glaucomatous ophthalmoscopic changes and then re-examined the same patients eight to 12 weeks later. The intervention’s odds of improving residents’ diagnostic impression were significant (OR=2.2; 95% CI=1.3–36), with significant improvement in sensitivity (p=0.02) and a trend toward improved specificity. These findings confirm that the diagnosis of glaucomatous ocular changes on eye examinations by medicine residents can be improved with a brief educational intervention.