Paul R. Yarnold Optimal Data Analysis, LLC The lead note in the Errata section of Optimal Data Analysis presents the corrected illustration of the first CTA model published in the field of medicine, two decades ago. View journal article

Fred B. Bryant & Paul R. Yarnold Optimal Data Analysis, LLC Recent research tested the a priori hypothesis that Type A Behavior (TAB) undermines enjoyment of leisure time, and that this effect is mediated by savoring responses which hamper enjoyment. Findings suggested that the hypothesized A-B differences in savoring reflect differences in perfectionism rather than … Continue reading Type A Behavior and Savoring Among College Undergraduates: Enjoy Achievements Now—Not Later

Robert C. Soltysik & Paul R. Yarnold Optimal Data Analysis, LLC Identification and detection of adverse drug reactions (ADRs) is critical to patient safety improvement, and warfarin is a medication known to be associated with a high rate of ADRs. Hierarchically optimal CTA was used to predict ADRs attributable to medications taken in addition to … Continue reading Hierarchically Optimal Classification Tree Analysis of Adverse Drug Reactions Secondary to Warfarin Therapy

Paul R. Yarnold & Robert C. Soltysik Optimal Data Analysis, LLC Hospital admission status, Emergency Severity Index (ESI) Version 3 triage score, and binary indicators of whether lab work or radiological examinations were completed in the Emergency Department (ED), were available for 160,471 patients seen over a three-year period in the ED of a leading … Continue reading Emergency Severity Index (Version 3) Score Predicts Hospital Admission

Paul R. Yarnold Optimal Data Analysis, LLC Arbitrary parsing of ordinal variables is omnipresent throughout the literature. A hypothetical example demonstrates how arbitrary parsing can reduce the accuracy of a statistical model. View journal article

Paul R. Yarnold Optimal Data Analysis, LLC The effect of serum cholesterol level on coronary heart disease and mortality was assessed for middle aged diabetic men in a prospective population study.1 Logistic regression was used to test the linear trend over quintiles, yielding estimated p<0.02. However the validity of the estimated Type I error rate … Continue reading UniODA vs. Logistic Regression: Serum Cholesterol and Coronary Heart Disease and Mortality Among Middle Aged Diabetic Men

Paul R. Yarnold Optimal Data Analysis, LLC This 27-year follow-up investigated long-term stability of Type A behavior (TAB) for 1,180 surviving participants in the Western Collaborative Group Study. The kappa statistic was used to assess reliability among and between self- and Structured Interview-based TAB assessments. Results indicated fair temporal reliability for self-assessments (kappa=0.39), moderate temporal … Continue reading UniODA vs. Kappa: Evaluating the Long-Term (27-Year) Test-Retest Reliability of the Type A Behavior Pattern

Paul R. Yarnold Optimal Data Analysis, LLC This study investigated the concordance between clinician and patient assessments of patient’s physical and mental functioning, made using 4-category ordinal scales, for a consecutive sample of 166 outpatients with rheumatoid arthritis. Weighted kappa isn’t a normed statistic, but the respective weighted kappa statistic obtained for the assessments, 0.39 … Continue reading UniODA vs. Weighted Kappa: Evaluating Concordance of Clinician and Patient Ratings of the Patient’s Physical and Mental Health Functioning

Paul R. Yarnold Optimal Data Analysis, LLC Kagan and Snidman investigated processes mediating early reactivity to stimulation in a longitudinal study of 94 four-month-old infants who displayed a combination of either high motor activity and frequent crying, or low motor activity and infrequent crying. Fearful behavior assessed at 9 and 14 months of age was … Continue reading UniODA vs. Chi-Square: Discriminating Inhibited and Uninhibited Infant Profiles

Paul R. Yarnold Optimal Data Analysis, LLC This study evaluates the number of migraine attacks experienced in a clinical trial of two alternative treatments, for a sample of 67 patients. Several conventional statistical methods were used to compare the number of attacks between treatments, but all of these methods were compromised by violations of their … Continue reading UniODA vs. Student’s t-Test: Comparing Two Migraine Treatments

Paul R. Yarnold Optimal Data Analysis, LLC This study compares 10-month-old infant smile status and inter-glance interval for attentive versus inattentive mothers. Statistical analysis by chi-square found no significant effects, while UniODA found that infants with inattentive mothers smile less often, with greater inter-glance intervals. View journal article