The interobserver reliability of pretest probability assessment in patients with suspected pulmonary embolism.

INTRODUCTION: Pretest probability assessment and objective testing are combined to appropriately manage patients with suspected pulmonary embolism (PE). However, the interobserver reliability of pretest probability assessment has not been investigated. We sought to determine (for patients with suspected PE) the interobserver reliability of pretest probability assessment (by overall impression (gestalt) versus an explicit clinical model). MATERIALS AND METHODS: A prospective cohort study was conducted at an urban university hospital. For patients referred for ventilation and perfusion (V/Q) scanning for suspected PE, structured assessments (11 history and 4 physical examination parameters) were performed by a referring physician and a designated thrombosis physician. The referring and thrombosis physicians also assigned a pretest probability for PE (low, moderate, or high) by gestalt. An explicit seven-point clinical model for suspected PE was later applied to each structured assessment to determine the pretest probability. Assessments were performed independently and prior to diagnostic test results. Interobserver reliability (two rater unweighted Kappa (kappa) statistic) was determined for each parameter on the structured assessment and the pretest probability assessments (gestalt vs. explicit clinical model). RESULTS: One hundred and ten patients with suspected PE received duplicate assessments. Historical features demonstrated substantial to almost perfect interobserver reliability (kappa=0.60-0.95). For the physical findings, only heart rate had substantial interobserver reliability (kappa=0.60). Pretest probability assessment was not reliable when using physician's gestalt (kappa=0.33), but produced substantial interobserver reliability using the explicit clinical model (kappa=0.62). CONCLUSIONS: Given the inadequate interobserver reliability of pretest probability assessment by overall impression (or gestalt), physicians should use explicit clinical models in the diagnostic management of patients with suspected pulmonary embolism.

A systematic review of the association between factor V Leiden or prothrombin gene variant and intrauterine growth restriction.

OBJECTIVE: The purpose of this study was to conduct a systematic review of the literature of studies that examined the association between factor V Leiden and/or prothrombin gene variant and intrauterine growth restriction. STUDY DESIGN: This systematic review of studies assesses the association between factor V Leiden and/or prothrombin gene variant and intrauterine growth restriction. RESULTS: Ten case-control studies fulfilled the selection criteria for inclusion in the meta-analysis. There was a significant association between factor V Leiden and intrauterine growth restriction (odds ratio, 2.7; 95% CI, 1.3-5.5) and prothrombin gene variant and intrauterine growth restriction (odds ratio, 2.5; 95% CI, 1.3-5.0). Five cohort studies were identified in the systematic review; 3 studies were prospective (2 full publications), and 2 studies were retrospective (1 full publication). Combining the 2 full publication prospective studies yields a summary relative risk of 0.99 (95% CI, 0.5-1.9). CONCLUSION: This meta-analysis of case-control studies suggests that the factor V Leiden and prothrombin gene variant both confer an increased risk of giving birth to an intrauterine growth restricted infant, although this may be driven by small, poor-quality studies that demonstrated extreme associations. Large well-conducted prospective cohort studies are required to determine definitively whether an association between thrombophilia and intrauterine growth restriction is present.