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Objetivo Evaluar la variabilidad interobservador en el uso de la versión 2.0 del PI- RADS (PI-RADS v2), en lectores experimentados y no experimentados. Materiales y Métodos Estudio retrospectivo de análisis de concordancia de lectores. Entre enero de 2015 y diciembre de 2016, 1.656 sujetos fueron estudiados mediante resonancia magnética multiparamétrica (RMmp) de próstata en nuestra institución. Se estimó la distribución porcentual del reporte en categoría PI-RADS v2, y con esa información, se realizó una selección de 150 casos con esquema de aleatorización estratificada a las distribuciones porcentuales de cada categoría. Dichos casos fueron anonimizados, presentados a tres lectores con cinco, cuatro y dos años de experiencia en lectura de RMmp además de tener más de un año de experiencia en el uso del PI- RADS v2 siendo leídos en forma individual. Los datos resultantes fueron analizados en forma independiente por un cuarto investigador. Resultados El valor de kappa ponderado para los observadores fue de 0,69 (IC 95: 0,64 a 0,75). La mayor concordancia correspondió a los lectores de mayor experiencia, donde alcanza un valor de 0,72 (IC 95%: 0,69 a 0,76). La concordancia entre los valores PI-RADS que determinan seguimiento o bien una intervención de acuerdo a elementos clínicos (1-2-3) y conducta activa (4-5) correspondió a 0,70 (IC 95%: 0,59 a 0,78). Discusión Se logró demostrar un acuerdo sustancial entre radiólogos utilizando el PI- RADS v2 para la detección en RMmp de lesiones sospechosas, mayor entre los dos lectores más experimentados. Sin embargo, la comparación del lector de menor experiencia con los de mayor experiencia también presentó una importante concordancia. Los valores de concordancia entre observadores para PI-RADS 2:4 fueron similares a los reportados en la literatura. Conclusiones El PI-RADSv2 ha demostrado en nuestro centro, con radiólogos dedicados a imágenes de abdomen y estudios de próstata, un alto nivel de acuerdo en la interpretación de la RMmp de próstata, encontrándose a tono con lo reportado en la literatura.
Purpose To evaluate the interobserver variability in the use of the PI-RADS 2.0 version, in experienced and non-experienced readers. Material and Methods Retrospective studyof readers' concordance analysis. Between January 2015 and December 2016, 1656 subjects were studied through multiparametric MRI (RMmp) of prostate in our institution. The percentage distribution of the report was estimated in each PI-RADS category, and a selection of 150 cases with a stratified randomization scheme was made to the percentage distributions of every category. These cases were anonymized, presented to three readers with 5, 4 and 2 years' experience in reading RMmp, and more than one-year experience with PI-RADS v2, and were read individually. The resulting data were analyzed independently by a fourth investigator. Results The weighted kappa value for the observers was 0.69 (IC 95: 0.64 to 0.75). The highest agreement corresponded to the two most experienced readers, where it reached a value of 0.72 (95% CI: 0.69 to 0.76). The concordance between the PI-RADS values that determine follow-up (1-2-3) and active behavior (4-5) corresponded to 0.70 (95% CI: 0.59 to 0.78). Discussion It was possible to demonstrate a substantial agreement between radiologists using the PI-RADS v2 for the detection in RMmp of suspicious lesions, greater among the two most experienced readers. However, the comparison of the less experienced reader with those of greater experience also presented an important concordance. The inter-observer concordance values for PI-RADS 2:4 were like those reported in the literature. Conclusions The PI-RADS v2 has demonstrated, in our center, with radiologists dedicated to abdominal images and prostate studies, a high level of agreement in the interpretation of prostate MRmp.
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Objective@#To assess the interobserver variations in delineating the planning target volume (PTV) and organs at risk (OAR) using different contouring methods during intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC), aiming to provide references for the quality control of multi-center clinical trials.@*Methods@#The PTV and OAR of CT image of 1 NPC patient manually delineated by 10 physicians from 8 different radiation centers were defined as the " manual contour group" , and the OAR auto-contoured using the ABAS software and modified by the physicians were defined as the " auto+ manual contour group" . The maximum/minimum ratio (MMR) of the PTV and OAR volumes, and the coefficient of variation (CV) for different delineated contours were comparatively evaluated.@*Results@#Large variation was observed in the PTV and OAR volumes in the manual contour group. The MMR and CV of the PTV were 1.72-3.41 and 0.16-0.39, with the most significant variation in the PTVnd (MMR=3.41 and CV=0.39 for the PTVnd-L). The MMR and CV of the manually contoured OAR were 1.30-7.89 and 0.07-0.67. The MMR of the temporal lobe, spinal cord, temporomandibular joint, optic nerve and pituitary gland exceeded 2.0. Compared with the manual contour group, the average contouring time in the auto+ manual group was shortened by 68% and the interobserver variation of the OAR volume was reduced with an MMR of 1.04-2.44 and CV of 0.01-0.37.@*Conclusions@#Large variation may occur in the PTV and OAR contours during IMRT plans for NPC delineated by different clinicians from multiple medical centers. Auto-contouring+ manually modification can reduce the interobserver variation of OAR delineation, whereas the variation in the delineation of small organs remains above 1.5 times. The consistency of the PTV and OAR delineation and the possible impact upon clinical outcomes should be reviewed and evaluated in multi-center clinical trials.
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Objective To assess the interobserver variations in delineating the planning target volume (PTV) and organs at risk (OAR) using different contouring methods during intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC),aiming to provide references for the quality control of multi-center clinical trials.Methods The PTV and OAR of CT image of 1 NPC patient manually delineated by 10 physicians from 8 different radiation centers were defined as the "manual contour group",and the OAR auto-contoured using the ABAS software and modified by the physicians were defined as the "auto+manual contour group".The maximum/minimum ratio (MMR) of the PTV and OAR volumes,and the coefficient of variation (CV) for different delineated contours were comparatively evaluated.Results Large variation was observed in the PTV and OAR volumes in the manual contour group.The MMR and CV of the PTV were 1.72-3.41 and 0.16-0.39,with the most significant variation in the PTVnd (MMR=3.41 and CV =0.39 for the PTVnd-L).The MMR and CV of the manually contoured OAR were 1.30-7.89 and 0.07-0.67.The MMR of the temporal lobe,spinal cord,temporomandibular joint,optic nerve and pituitary gland exceeded 2.0.Compared with the manual contour group,the average contouring time in the auto+ manual group was shortened by 68％ and the interobserver variation of the OAR volume was reduced with an MMR of 1.04-2.44 and CV of 0.01-0.37.Conclusions Large variation may occur in the PTV and OAR contours during IMRT plans for NPC delineated by different clinicians from multiple medical centers.Auto-contouring+ manually modification can reduce the interobserver variation of OAR delineation,whereas the variation in the delineation of small organs remains above 1.5 times.The consistency of the PTV and OAR delineation and the possible impact upon clinical outcomes should be reviewed and evaluated in multi-center clinical trials.
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PURPOSE: To investigate interobserver variation in target volume delineations for prostate cancer salvage radiotherapy using planning computed tomography (CT) versus combined planning CT and magnetic resonance imaging (MRI). MATERIALS AND METHODS: Ten radiation oncologists independently delineated a target volume on the planning CT scans of five cases with different pathological status after radical prostatectomy. Two weeks later, this was repeated with the addition of planning MRI. The volumes obtained with CT only and combined CT and MRI were compared, and the effect of the addition of planning MRI on interobserver variability was assessed. RESULTS: There were large differences in clinical target volume (CTV) delineated by each observer, regardless of the addition of planning MRI (9.44–139.27 cm³ in CT only and 7.77–122.83 cm³ in CT plus MRI) and no significant differences in the mean and standard deviation of CTV. However, there were decreases in mean volume and standard deviation as a result of using the planning MRI. CONCLUSION: This study showed substantial interobserver variation in target volume delineation for salvage radiotherapy. The combination of planning MRI with CT tended to decrease the target volume and the variation.
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Humans , Magnetic Resonance Imaging , Observer Variation , Prostate , Prostatectomy , Prostatic Neoplasms , Radiotherapy , Tomography, X-Ray ComputedABSTRACT
PURPOSE: The degree of radiation-induced lung fibrosis (RILF) can be measured quantitatively by fibrosis volume (VF) on chest computed tomography (CT) scan. The purpose of this study was to investigate the interobserver and intraobserver variability in CT-based measurement of VF. MATERIALS AND METHODS: We selected 10 non-small cell lung cancer patients developed with RILF after postoperative radiation therapy (PORT) and delineated VF on the follow-up chest CT scanned at more than 6 months after radiotherapy. Three radiation oncologists independently delineated VF to investigate the interobserver variability. Three times of delineation of VF was performed by two radiation oncologists for the analysis of intraobserver variability. We analysed the concordance index (CI) and inter/intraclass correlation coefficient (ICC). RESULTS: The median CI was 0.61 (range, 0.44 to 0.68) for interobserver variability and the median CIs for intraobserver variability were 0.69 (range, 0.65 to 0.79) and 0.61(range, 0.55 to 0.65) by two observers. The ICC for interobserver variability was 0.974 (p < 0.001) and ICCs for intraobserver variability were 0.996 (p < 0.001) and 0.991 (p < 0.001), respectively. CONCLUSION: CT-based measurement of VF with patients who received PORT was a highly consistent and reproducible quantitative method between and within observers.
Subject(s)
Humans , Carcinoma, Non-Small-Cell Lung , Evaluation Studies as Topic , Fibrosis , Follow-Up Studies , Lung , Observer Variation , Radiotherapy , Thorax , Tomography, X-Ray ComputedABSTRACT
Background & objectives: Bacterial vaginosis (BV) is the most common form of vaginal infection and an important cause of morbidity in women of reproductive age. This study was carried out to examine the interobserver variation on interpretation of Nugent scoring method in the diagnosis of BV. Methods: This prospective study was conducted in a rural primary health care center of north India from May 2003 to April 2004 and included 601 married, sexually active women between 18-49 yr of age presented with self-reported symptoms of vaginal discharge and/or genital itching and/or genital burning. Specimens collected from the lateral wall of vagina were subjected to Gram staining and the microscope slide smears were examined by 3 independent observers. Each of the three observers scored and interpreted the slides for diagnosis of bacterial vaginosis using the Nugent method. Results: Complete agreement amongst the three observers was found in 76.2 per cent of cases. In 22.13 per cent cases, two observers were in agreement while interpretation of the slides were in complete disagreement only in 1.66 per cent of cases. The interrater reproducibility was found to be excellent between observers 1 and 3, while between observers 1 and 2, and 2 and 3 it was good to fair. Interpretation & conclusions: Nugent scoring system appears to be a reliable and convenient method for laboratory evaluation of cases of bacterial vaginosis. At the same time, one must be aware of the factors that might lead to discrepant results.
Subject(s)
Female , Humans , India , Observer Variation , Prospective Studies , Rural Health Services , Vaginosis, Bacterial/diagnosisABSTRACT
[Objeetive] To assess the reproducibility and accuracy of four ratios used to measure patellar height,named the Blackburne-Peel,Caton Deschamps,Insall-Salvati and modified Insall-Salvati,before and after totalknee arthroplasty.[Methods]The patellar height was measured,by means of the four ratios,on the pre-and post-operative lateral radiographs of 44 patients(45 knees)who had undergone total knee arthroplasty.Two independent observers measured the films sequentially,in identical conditions,totally 720 measurements per observer.[Results]Before operation there was greater interobserver variation using either the Insall-Salvati or modified Insall-Salvati ratios than that when using the Caton-Deschamps or Blackburne-Peel methods.This was due to difficulty in identifying the insertion of the patellar tendon.Before operation,there was a minimal difference in reliability between these methods.After operation the interobserver difference was greatly reduced using both the Caton-Deschamps and Blackburne-Peel methods,which used the prosthetic joint line,compared with the Insall-Salvati and modified Insall-Salvati,which refered to the insertion of the patellar tendon.[Conclusion]The theoretical advantage of using the Insall-Salvati and modified Insall-Salvati ratios in measuring true patellar height after total knee arthroplasty needs to be balanced against their significant interobserver variability and inferior reliability when compared with other ratios.
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BACKGROUND/AIMS: Capsule endoscopy (CE) is a new method enabling noninvasive diagnosis of small bowel diseases. There have been few studies examining the possibility of interobserver variation according to proficiency. We evaluated the interobserver variability between expert and novice for reviewing CE images. METHODS: Among patients who were taken CE from June 2003 to July 2003, twenty patients were randomly selected. Captured images were assessed by an expert and a novice separately. The expert has experience of more than 150 CE interpretation and the novice only had experience in performing EGD and colonoscopy. The novice had trained on interpretation of the CE with 5 cases before this study. Interobserver agreement was evaluated using kappa coefficient. RESULT: CE findings were divided into normal/ abnormal groups. Abnormal groups were classified into small focal, large focal, multiple diffuse, structural deformity groups. Compared with the expert, the novice missed 2 cases (Meckel's diverticulum and angiodysplasia). There was no disagreement in other cases. CONCLUSION: There is 90% (18/20) interobserver agreement between the expert and the novice for the interpetation of findings CE (k=0.737). Normal findings and diffuse large lesions tended to have higher concordance, whereas small focal lesion and structural deformities were more likely to be a source of disagreement.