Assessment of performance measures and learning curves for use of a virtual-reality ultrasound simulator in transvaginal ultrasound examination.

OBJECTIVE: To assess the validity and reliability of performance measures, develop credible performance standards and explore learning curves for a virtual-reality simulator designed for transvaginal gynecological ultrasound examination. METHODS: A group of 16 ultrasound novices, along with a group of 12 obstetrics/gynecology (Ob/Gyn) consultants, were included in this experimental study. The first two performances of the two groups on seven selected modules on a high-fidelity ultrasound simulator were used to identify valid and reliable metrics. Performance standards were determined and novices were instructed to continue practicing until they attained the performance level of an expert subgroup (n = 4). RESULTS: All 28 participants completed the selected modules twice and all novices reached the expert performance level. Of 153 metrics, 48 were able to be used to discriminate between the two groups' performance. The ultrasound novices scored a median of 43.8% (range, 17.9-68.9%) and the Ob/Gyn consultants scored a median of 82.8% (range, 60.4-91.7%) of the maximum sum score (P < 0.001). The ultrasound novices reached the expert level (88.4%) within a median of five iterations (range, 5-6), corresponding to an average of 219 min (range, 150-251 min) of training. The test/retest reliability was high, with an intraclass correlation coefficient of 0.93. CONCLUSIONS: Competence in the performance of gynecological ultrasound examination can be assessed in a valid and reliable way using virtual-reality simulation. The novices' performance improved with practice and their learning curves plateaued at the level of expert performance, following between 3 and 4 h of simulator training.

Reliable and valid assessment of ultrasound operator competence in obstetrics and gynecology.

OBJECTIVES: To explore the reliability and validity of a recently developed instrument for assessment of ultrasound operator competence, the Objective Structured Assessment of Ultrasound Skills (OSAUS). METHODS: Three groups of 10 doctors with different levels of ultrasound experience in obstetrics and gynecology were included. The novices had less than 1 month of experience, the intermediate group had 12-60 months of experience and the senior participants were all consultants. Fifteen participants performed transabdominal fetal biometry and the other 15 participants performed systematic transvaginal gynecological ultrasound scans. All scans were video-recorded and assessed by two blinded consultants using the OSAUS scale. The OSAUS scores were compared between the groups using the Kruskal-Wallis test, and pass/fail scores were determined using the contrasting-groups method of standard setting. RESULTS: For the transabdominal fetal biometry examinations, the mean ± SD OSAUS scores of the novices, intermediates and senior participants were 1.5 ± 0.4, 3.3 ± 0.6 and 4.4 ± 0.4, respectively (P = 0.003). For the systematic transvaginal scans, the mean ± SD OSAUS scores of the novices, intermediates and senior participants were 1.8 ± 0.2, 3.1 ± 0.1 and 3.9 ± 0.5, respectively (P = 0.003). Post-hoc comparisons showed significant differences between each of the groups for both types of scans. The pass/fail score was 2.5 for the transvaginal scan and 3.0 for the transabdominal biometry examinations. The inter-rater reliability was 0.89. CONCLUSIONS: Ultrasound competence can be assessed in a reliable and valid way using the OSAUS scale. The pass/fail scores may be used to help determine when trainees are qualified for independent practice.

Does leisure time physical activity in early pregnancy protect against pre-eclampsia? Prospective cohort in Danish women.

OBJECTIVE: To examine the association between physical activity in early pregnancy and risk of pre-eclampsia. DESIGN: Prospective cohort. SETTING: Denmark. POPULATION: A total of 85,139 pregnant Danish women, recruited between 1996 and 2002. METHODS: The authors assessed leisure time physical activity in first trimester by a telephone interview and categorised women a priori into seven groups: 0 (reference), 1-44, 45-74, 75-149, 150-269, 270-419 and 420+ minutes/week. Pre-eclampsia diagnoses were extracted from the Danish National Patient Registry. A number of potential confounders were adjusted for by logistic regression. MAIN OUTCOME MEASURES: Pre-eclampsia and severe pre-eclampsia. RESULTS: The two highest physical activity levels were associated with increased risk of severe pre-eclampsia compared with the nonexercising group, with adjusted odds ratios of 1.65 (95% CI: 1.11-2.43) and 1.78 (95% CI: 1.07-2.95), whereas more moderate levels of physical activity (1-270 minutes/week) had no statistically significant association with risk of pre-eclampsia (total n = 85,139). CONCLUSIONS: We were unable to document a protective effect of leisure time physical activity against pre-eclampsia. Our data even suggest that leisure time physical activity exceeding 270 minutes/week in first trimester may increase risk of severe pre-eclampsia.