Improving the ability to discriminate medical multiple-choice questions through the analysis of the competitive examination to assign residency positions in Spain.

INTRODUCTION: Psychometrics plays a vital role in evaluating educational research, including the analysis of multiple-choice exams. This study aims to improve the discriminatory ability of the "Médico Interno Residente" (MIR) medical exam in Spain, used to rank candidates for specialized healthcare training, through psychometric analysis. METHODS: We analyzed 2,890 MIR exam questions from 2009 to 2021 (totaling 147,214 exams), categorizing them based on methodology and response type. Evaluation employed classical test theory and item response theory (IRT). Classical test theory determined difficulty and discrimination indices, while IRT assessed the relationship between knowledge levels and question performance. RESULTS: Question distribution varied across categories and years. Frequently addressed knowledge areas included various medical specialties. Non-image-associated clinical cases were the easiest, while case-based clinical questions exhibited the highest discriminatory capacity, differing significantly from image-based case or negative questions. High-quality questions without images had longer stems but shorter answer choices. Adding images reduced discriminatory power and question difficulty, with image-based questions being easier. Clinical cases with images had shorter stems and longer answer choices. CONCLUSIONS: For improved exam performance, we recommend using a clinical case format followed by direct short-answer questions. Questions should be of low difficulty, providing clear and specific answers based on scientific evidence and avoiding ambiguity. Typical clinical cases with key characteristic features should be presented, excluding uncertain boundaries of medical knowledge. Questions should have lengthy stems and concise answer choices, minimizing speculation. If images are used, they should be typical, clear, consistent with the exam, and presented within clinical cases using clinical semiotics and propaedeutics.

Amino-terminal pro-B-type natriuretic peptide, inferior vena cava ultrasound, and biolectrical impedance analysis for the diagnosis of acute decompensated CHF.

BACKGROUND: Both Framingham criteria and natriuretic peptides (NPs) may worsen their diagnostic validity for acute decompensated heart failure (ADHF) in elderly patients with comorbidities, mainly renal failure. Ultrasound of inferior vena cava (IVCu) and bioelectrical impedance analysis (BIA) are useful tools for detecting ADHF, although their utility compared with NP is not fully established. METHODS AND RESULTS: We conducted a prospective study with 96 patients who presented at the emergency department with dyspnea and were classified as ADHF and non-ADHF groups. Inferior vena cava ultrasonography measured maximum and minimum inferior vena cava diameters and collapsibility index (CIx), whereas BIA calculated resistance (Rz) and reactance (Xc). The primary goal was to compare amino-terminal pro-B-type NP (NT-proBNP), IVCu, and BIA for identifying ADHF. The ADHF group showed significantly (P<.001) higher NT-proBNP values (5801 vs 599 pg/mL), higher maximum IVC diameter (2.26 vs 1.58 cm), higher minimum IVC diameter (1.67 vs 0,7 cm), and lower CIx (27% vs 59%), as well as lower Rz (458.8 vs 627.1 Ohm) and lower Xc (23.5 vs 38.4 Ohm) compared with the non-ADHF group. The estimated area under the curve for ADHF diagnosis was 0.84 for NT-proBNP, 0.90 for maximum IVC diameter, 0.93 for minimum IVC diameter, and 0.90 for CIx, as well as 0.83 and 0.80 for Rz and Xc respectively, without finding significant difference. Cutoff values for diagnosis of ADHF with IVCu and BIA are proposed. Amino-terminal pro-B-type NP values significantly varied in patients with renal impairment, independently of ADHF status, whereas neither IVCu nor BIA did. CONCLUSIONS: Inferior vena cava ultrasonography and BIA analysis are as useful as NT-proBNP to ADHF diagnosis, validated in an elderly population with kidney disease.