{"analyses":[{"groupDescription":"Pairwise comparison for each direction between each pair of technologies were done using a t test to check if the difference in the recommended shift is more than 2 mm. Clinical significance is based on a 2 mm difference. Statistical significance is determined based on 5% level of significance.","groupIds":["OG000","OG001"],"nonInferiorityComment":"Statistical significance testing at 5% level of significance, p-value being larger than 0.05 . The p-values for pairwise comparison.","nonInferiorityType":"NON_INFERIORITY_OR_EQUIVALENCE","pValue":"1.00","pValueComment":"Statistical significance testing at 5% level of significance, p-value being larger than 0.05. The p-values for pairwise comparison lateral and vertical, for OBI and CBCT was 1.00.","statisticalMethod":"t-test, 2 sided","testedNonInferiority":true},{"groupDescription":"Pairwise comparison for each direction between each pair of technologies were done using a t test to check if the difference in the recommended shift is more than 2 mm. Clinical significance is based on a 2 mm difference. Statistical significance is determined based on 5% level of significance.","groupIds":["OG000","OG002"],"nonInferiorityComment":"Statistical significance testing at 5% level of significance, p-value being larger than 0.05. Those are the p-values for pairwise comparison.","nonInferiorityType":"NON_INFERIORITY_OR_EQUIVALENCE","pValue":"1.00","pValueComment":"Statistical significance testing at 5% level of significance, p-value being larger than 0.05. The p-values for pairwise comparison lateral and vertical, for OBI and ExacTrac was 1.00.","statisticalMethod":"t-test, 2 sided","testedNonInferiority":true}],"classes":[{"categories":[{"measurements":[{"groupId":"OG000","spread":"3.1","value":"-1.2"},{"groupId":"OG001","spread":"3.4","value":"-0.8"},{"groupId":"OG002","spread":"3.2","value":"-1.8"}]}],"title":"Vertical shift"},{"categories":[{"measurements":[{"groupId":"OG000","spread":"3.3","value":"-1.5"},{"groupId":"OG001","spread":"3.3","value":"-1.1"},{"groupId":"OG002","spread":"3.9","value":"1.3"}]}],"title":"Lateral shift"}],"denoms":[{"counts":[{"groupId":"OG000","value":"10"},{"groupId":"OG001","value":"10"},{"groupId":"OG002","value":"10"}],"units":"Participants"}],"description":"The automated patient setup procedure varies between 'OBI', 'CBCT' or 'Exactrac' imaging technologies. Each procedure gives two shifts: 'vertical' and 'lateral'. In the absence of a gold standard, our goal is to compare the shifts recommended by each pair of automated patient setup procedures. Average and Std deviation of vertical and lateral motion from the three systems were computed. P value, 1.00, refers to the test of difference of each system with OBI being more than 2 mm. Pairwise comparison for each direction between each pair of technologies were done using a t test to check if the difference in the recommended shift is more than 2 mm. The reported mean value represents the shift from planned treatment position averaged over all daily treatment setups. A negative mean vertical value indicates the patient was consistently set up posterior to plan; a negative mean lateral value indicates a set up consistently right of plan.","dispersionType":"Standard Deviation","groups":[{"description":"Patients are first set up for treatment with surface fiducial marks and followed by an automated image guided alignment procedure to achieve better alignment with the planning image. The automated procedure OBI gives two shifts: vertical and lateral. In the absence of a gold standard, our goal is to compare the vertical and lateral shifts recommended by each pair of automated procedures.","id":"OG000","title":"Orthogonal Varian kV OBI Image"},{"description":"Patients are first set up for treatment with surface fiducial marks and followed by an automated image guided alignment procedure to achieve better alignment with the planning image. The automated procedure CBCT gives two shifts: vertical and lateral. In the absence of a gold standard, our goal is to compare the vertical and lateral shifts recommended by each pair of automated procedures.","id":"OG001","title":"Varian CBCT (Cone Beam CT) Imaging"},{"description":"Patients are first set up for treatment with surface fiducial marks and followed by an automated image guided alignment procedure to achieve better alignment with the planning image. The automated procedure ExacTrac gives two shifts: vertical and lateral. In the absence of a gold standard, our goal is to compare the vertical and lateral shifts recommended by each pair of automated procedures.","id":"OG002","title":"Oblique Brainlab ExacTrac Images"}],"paramType":"MEAN","populationDescription":"Ten evaluable head and neck patients treated with external beam radiation therapy received 19 to 32 fractions with all three imaging techniques. The mean daily shift of these 19 to 32 fractions were recorded for each technique. Statistical significance is determined based on 5% level of significance.","reportingStatus":"POSTED","timeFrame":"up to 7 weeks","title":"Differences of Calculated Set up Errors of 2 mm Between the Different Imaging Technologies","type":"PRIMARY","unitOfMeasure":"mm"}