{"id":1185,"date":"2024-04-11T14:39:21","date_gmt":"2024-04-11T11:39:21","guid":{"rendered":"https:\/\/sisu.ut.ee\/lcms_method_validation\/self-test-9-4\/"},"modified":"2024-04-11T14:39:21","modified_gmt":"2024-04-11T11:39:21","slug":"self-test-9-4","status":"publish","type":"page","link":"https:\/\/sisu.ut.ee\/lcms_method_validation\/self-test-9-4\/","title":{"rendered":"Self test 9.4"},"content":{"rendered":"<div id=\"watupro_quiz\" class=\"quiz-area single-page-quiz\">\n<p id=\"submittingExam12\" style=\"display:none;text-align:center;\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/sisu.ut.ee\/wp-content\/plugins\/watupro\/img\/loading.gif\" width=\"16\" height=\"16\"><\/p>\n\n\n\n<form action=\"\" method=\"post\" class=\"quiz-form\" id=\"quiz-12\" enctype=\"multipart\/form-data\">\n<div class=\"watu-question \" id=\"question-1\" style=\";\"><div id=\"questionWrap-1\" class=\"   watupro-question-id-38\">\n\t\t\t<div class=\"question-content\"><div><span class=\"watupro_num\">1. <\/span>An LC-MS\/MS analysis method has been developed to measure amount of leucine from blood (elevated levels of this amino acid can indicate pancreatic cancer). The received information about the concentrations of the analyte will be used for research purposes only.<br>\r\n<br>\r\nIn this research it is important that the results received from the analysis would be with acceptable accuracy at concentration of above a critical level that indicates the presence of the disease.\u00a0Therefore, accuracy at different concentration levels must be known to estimate LoQ.<br>\r\n<br>\r\nWhich of the following statements are true:<\/div><input type=\"hidden\" name=\"question_id[]\" id=\"qID_1\" value=\"38\" class=\"watupro-question-id\"><input type=\"hidden\" id=\"answerType38\" class=\"answerTypeCnt1\" value=\"checkbox\"><!-- end question-content--><\/div><div class=\"question-choices watupro-choices-columns \" id=\"questionChoices38\"><div class=\"watupro-question-choice  \" dir=\"auto\"><input type=\"checkbox\" name=\"answer-38[]\" id=\"answer-id-120\" class=\"answer   answerof-38 \" value=\"120\"><label for=\"answer-id-120\" id=\"answer-label-120\" class=\" answer\"><span><p>LoQ must be estimated by approach specified by FDA because they regulate the validation of analytical methods used for diagnostics.<\/p><\/span><\/label><\/div><div class=\"watupro-question-choice  \" dir=\"auto\"><input type=\"checkbox\" name=\"answer-38[]\" id=\"answer-id-121\" class=\"answer   answerof-38 \" value=\"121\"><label for=\"answer-id-121\" id=\"answer-label-121\" class=\" answer\"><span><p>Precision and trueness should be estimated at different concentrations. LoQ of the method is the concentration at which these parameters are acceptably low. However, if the LoQ of the method is significantly above the critical level of the biomarker then the method should be developed further to lower the LoQ.<\/p><\/span><\/label><\/div><div class=\"watupro-question-choice  \" dir=\"auto\"><input type=\"checkbox\" name=\"answer-38[]\" id=\"answer-id-122\" class=\"answer   answerof-38 \" value=\"122\"><label for=\"answer-id-122\" id=\"answer-label-122\" class=\" answer\"><span><p>LoQ should be found by using the ICH suggested approach where standard deviation of the residuals is divided by the slope of the calibration function and the result is multiplied by 10.<\/p><\/span><\/label><\/div><!-- end question-choices--><\/div><!-- end questionWrap--><\/div>\t\t\t\t\t<div style=\"display:none;\" id=\"liveResult-1\">\t\t   \n\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/sisu.ut.ee\/wp-content\/plugins\/watupro\/img\/loading.gif\" width=\"16\" height=\"16\" alt=\"Loading...\" title=\"Loading...\">\u00a0Loading...\t\t\t\t\t<\/div>\t\n\t\t\t<\/div> \n\t   \t<p id=\"liveResBtn-38\" style=\"clear:both;\"><input type=\"button\" id=\"liveResultBtn38\" class=\"liveResultBtn1 watupro-live-result-btn\" value=\"See Answer\" onclick=\"WatuPRO.liveResult(38, 1);\"><\/p>\n\t   <div class=\"watu-question \" id=\"question-2\" style=\";\"><div id=\"questionWrap-2\" class=\"   watupro-question-id-39\">\n\t\t\t<div class=\"question-content\"><p><span class=\"watupro_num\">2. <\/span>Precision and trueness of an analysis method that measures imazalil from oranges were estimated at different concentrations:<\/p>\n<table style=\"border-collapse: collapse; width: 30%;\" border=\"1\" width=\"192\" cellspacing=\"0\" cellpadding=\"0\">\n<tbody>\n<tr style=\"height: 14.5pt;\">\n<td style=\"height: 14.5pt; width: 48pt; border: 1px solid black; text-align: center;\" width=\"64\" height=\"19\"><strong>Concentration (mg\/kg)<\/strong><\/td>\n<td style=\"width: 48pt; border: 1px solid black; text-align: center;\" width=\"64\"><strong>Relative standard deviation<\/strong><\/td>\n<td style=\"width: 48pt; border: 1px solid black; text-align: center;\" width=\"64\"><strong>Recovery<\/strong><\/td>\n<\/tr>\n<tr style=\"height: 14.5pt;\">\n<td style=\"height: 14.5pt; border: 1px solid black; text-align: center;\" align=\"right\" height=\"19\">0.01<\/td>\n<td style=\"border: 1px solid black; text-align: center;\" align=\"right\">0.3<\/td>\n<td style=\"border: 1px solid black; text-align: center;\" align=\"right\">0.65<\/td>\n<\/tr>\n<tr style=\"height: 14.5pt;\">\n<td style=\"height: 14.5pt; border: 1px solid black; text-align: center;\" align=\"right\" height=\"19\">0.05<\/td>\n<td style=\"border: 1px solid black; text-align: center;\" align=\"right\">0.25<\/td>\n<td style=\"border: 1px solid black; text-align: center;\" align=\"right\">0.85<\/td>\n<\/tr>\n<tr style=\"height: 14.5pt;\">\n<td style=\"height: 14.5pt; border: 1px solid black; text-align: center;\" align=\"right\" height=\"19\">0.1<\/td>\n<td style=\"border: 1px solid black; text-align: center;\" align=\"right\">0.18<\/td>\n<td style=\"border: 1px solid black; text-align: center;\" align=\"right\">0.9<\/td>\n<\/tr>\n<tr style=\"height: 14.5pt;\">\n<td style=\"height: 14.5pt; border: 1px solid black; text-align: center;\" align=\"right\" height=\"19\">0.5<\/td>\n<td style=\"border: 1px solid black; text-align: center;\" align=\"right\">0.12<\/td>\n<td style=\"border: 1px solid black; text-align: center;\" align=\"right\">0.9<\/td>\n<\/tr>\n<tr style=\"height: 14.5pt;\">\n<td style=\"height: 14.5pt; border: 1px solid black; text-align: center;\" align=\"right\" height=\"19\">1<\/td>\n<td style=\"border: 1px solid black; text-align: center;\" align=\"right\">0.08<\/td>\n<td style=\"border: 1px solid black; text-align: center;\" align=\"right\">0.9<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>In this case SANTE\/SANCO guidelines must be followed.<\/p>\n<p><strong>Question:<\/strong> What is the LoQ of the method?<\/p>\n<p><strong>Answer:<\/strong> <select name=\"gap_39_1\" class=\"watupro-gap answer answerof-39\"><option value=\"\"><\/option><option value=\"1 mg\/kg\">1 mg\/kg<\/option><option value=\"0.1 mg\/kg\">0.1 mg\/kg<\/option><option value=\"0.05 mg\/kg\">0.05 mg\/kg<\/option><option value=\"0.01 mg\/kg\">0.01 mg\/kg<\/option><option value=\"0.5 mg\/kg\">0.5 mg\/kg<\/option><\/select><\/p>\n<input type=\"hidden\" name=\"question_id[]\" id=\"qID_2\" value=\"39\" class=\"watupro-question-id\"><input type=\"hidden\" id=\"answerType39\" class=\"answerTypeCnt2\" value=\"gaps\"><!-- end question-content--><\/div><!-- end questionWrap--><\/div>\t\t\t\t\t<div style=\"display:none;\" id=\"liveResult-2\">\t\t   \n\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/sisu.ut.ee\/wp-content\/plugins\/watupro\/img\/loading.gif\" width=\"16\" height=\"16\" alt=\"Loading...\" title=\"Loading...\">\u00a0Loading...\t\t\t\t\t<\/div>\t\n\t\t\t<\/div> \n\t   \t<p id=\"liveResBtn-39\" style=\"clear:both;\"><input type=\"button\" id=\"liveResultBtn39\" class=\"liveResultBtn2 watupro-live-result-btn\" value=\"See Answer\" onclick=\"WatuPRO.liveResult(39, 2);\"><\/p>\n\t   <div class=\"watu-question \" id=\"question-3\" style=\";\"><div id=\"questionWrap-3\" class=\"   watupro-question-id-40\">\n\t\t\t<div class=\"question-content\"><div><span class=\"watupro_num\">3. <\/span>Which of the following statements are true:<\/div><input type=\"hidden\" name=\"question_id[]\" id=\"qID_3\" value=\"40\" class=\"watupro-question-id\"><input type=\"hidden\" id=\"answerType40\" class=\"answerTypeCnt3\" value=\"checkbox\"><!-- end question-content--><\/div><div class=\"question-choices watupro-choices-columns \" id=\"questionChoices40\"><div class=\"watupro-question-choice  \" dir=\"auto\"><input type=\"checkbox\" name=\"answer-40[]\" id=\"answer-id-126\" class=\"answer   answerof-40 \" value=\"126\"><label for=\"answer-id-126\" id=\"answer-label-126\" class=\" answer\"><span><p>LoQ of an analysis method is used daily to interpret analysis results. Therefore, LoQ should be estimated regularly and a conservative LoQ estimate should be used.<\/p><\/span><\/label><\/div><div class=\"watupro-question-choice  \" dir=\"auto\"><input type=\"checkbox\" name=\"answer-40[]\" id=\"answer-id-125\" class=\"answer   answerof-40 \" value=\"125\"><label for=\"answer-id-125\" id=\"answer-label-125\" class=\" answer\"><span><p>LoQ for an approach is estimated that measures glyphosate (widely used pesticide) from soil. Simple water samples with spiked concentration of glyphosate can be used to estimate LoQ of the method.<\/p><\/span><\/label><\/div><div class=\"watupro-question-choice  \" dir=\"auto\"><input type=\"checkbox\" name=\"answer-40[]\" id=\"answer-id-124\" class=\"answer   answerof-40 \" value=\"124\"><label for=\"answer-id-124\" id=\"answer-label-124\" class=\" answer\"><span><p>LoQ can be estimated from calibration data in which lowest calibration level is above the estimated LoQ.<\/p><\/span><\/label><\/div><!-- end question-choices--><\/div><!-- end questionWrap--><\/div>\t\t\t\t\t<div style=\"display:none;\" id=\"liveResult-3\">\t\t   \n\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/sisu.ut.ee\/wp-content\/plugins\/watupro\/img\/loading.gif\" width=\"16\" height=\"16\" alt=\"Loading...\" title=\"Loading...\">\u00a0Loading...\t\t\t\t\t<\/div>\t\n\t\t\t<\/div> \n\t   \t<p id=\"liveResBtn-40\" style=\"clear:both;\"><input type=\"button\" id=\"liveResultBtn40\" class=\"liveResultBtn3 watupro-live-result-btn\" value=\"See Answer\" onclick=\"WatuPRO.liveResult(40, 3);\"><\/p>\n\t   <div class=\"watu-question \" id=\"question-4\" style=\";\"><div id=\"questionWrap-4\" class=\"   watupro-question-id-41\">\n\t\t\t<div class=\"question-content\"><div><span class=\"watupro_num\">4. <\/span>Estimate LoQ from given data collected from LC-MS\/MS measurements of meropenem (a broad-spectrum antibiotic) from blood. For estimating LoQ use the approach suggested by ICH that uses standard deviation of residuals (LoQ = 10 \u00d7 stdev(residulas) \/ slope).<br>\r\n<table style=\"border-collapse: collapse; width: 30%;\" border=\"1\" width=\"128\" cellspacing=\"0\" cellpadding=\"0\"><tbody><tr style=\"height: 14.5pt;\"><td style=\"height: 14.5pt; width: 48pt; text-align: center; border: 1px solid black;\" width=\"64\" height=\"19\"><strong>Concentration (mg\/kg)<\/strong><\/td><td style=\"width: 48pt; text-align: center; border: 1px solid black;\" width=\"64\"><strong>Intensity<\/strong><\/td><\/tr><tr style=\"height: 14.5pt;\"><td style=\"height: 14.5pt; text-align: center; border: 1px solid black;\" align=\"right\" height=\"19\">0.0005<\/td><td style=\"text-align: center; border: 1px solid black;\" align=\"right\">12053<\/td><\/tr><tr style=\"height: 14.5pt;\"><td style=\"height: 14.5pt; text-align: center; border: 1px solid black;\" align=\"right\" height=\"19\">0.005<\/td><td style=\"text-align: center; border: 1px solid black;\" align=\"right\">104341<\/td><\/tr><tr style=\"height: 14.5pt;\"><td style=\"height: 14.5pt; text-align: center; border: 1px solid black;\" align=\"right\" height=\"19\">0.0101<\/td><td style=\"text-align: center; border: 1px solid black;\" align=\"right\">272494<\/td><\/tr><tr style=\"height: 14.5pt;\"><td style=\"height: 14.5pt; text-align: center; border: 1px solid black;\" align=\"right\" height=\"19\">0.025<\/td><td style=\"text-align: center; border: 1px solid black;\" align=\"right\">676932<\/td><\/tr><tr style=\"height: 14.5pt;\"><td style=\"height: 14.5pt; text-align: center; border: 1px solid black;\" align=\"right\" height=\"19\">0.05<\/td><td style=\"text-align: center; border: 1px solid black;\" align=\"right\">869373<\/td><\/tr><tr style=\"height: 14.5pt;\"><td style=\"height: 14.5pt; text-align: center; border: 1px solid black;\" align=\"right\" height=\"19\">0.103<\/td><td style=\"text-align: center; border: 1px solid black;\" align=\"right\">1894379<\/td><\/tr><\/tbody><\/table>For use with ValChrom: <a href=\"https:\/\/sisu.ut.ee\/lcms_method_validation\/st_9-4_1_lod_loq-xls\/\" target=\"_blank\" rel=\"noopener\" data-fid=\"57424\">st_9.4_1_lod_loq.xls<\/a>\u00a0<br>\r\n<br>\r\nNotes:<br>\r\n<br>\r\nBefore estimating LoD use the plot of absolute residuals to estimate which of the highest calibration levels should be removed from data so that the data would be linear. Do not set intercept as zero as in case of these data it is known that the intercept can have a non zero value.<br>\r\n<br>\r\nFor use with ValChrom delete the lines that do not fit and reupload the CSV file.<br>\r\n<br>\r\nPlease write result rounded to 2 significant digits (unit: mg\/kg).<\/div><input type=\"hidden\" name=\"question_id[]\" id=\"qID_4\" value=\"41\" class=\"watupro-question-id\"><input type=\"hidden\" id=\"answerType41\" class=\"answerTypeCnt4\" value=\"textarea\"><!-- end question-content--><\/div><div class=\"question-choices \" id=\"questionChoices41\"><p><input type=\"text\" name=\"answer-41[]\" id=\"textarea_q_41\" class=\"watupro-text\" value=\"\" size=\"60\"><\/p><!-- end question-choices--><\/div><!-- end questionWrap--><\/div>\t\t\t\t\t<div style=\"display:none;\" id=\"liveResult-4\">\t\t   \n\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/sisu.ut.ee\/wp-content\/plugins\/watupro\/img\/loading.gif\" width=\"16\" height=\"16\" alt=\"Loading...\" title=\"Loading...\">\u00a0Loading...\t\t\t\t\t<\/div>\t\n\t\t\t<\/div> \n\t   \t<p id=\"liveResBtn-41\" style=\"clear:both;\"><input type=\"button\" id=\"liveResultBtn41\" class=\"liveResultBtn4 watupro-live-result-btn\" value=\"See Answer\" onclick=\"WatuPRO.liveResult(41, 4);\"><\/p>\n\t   <div style=\"display:none\" id=\"question-5\">\n\t<div class=\"question-content\">\n\t\t<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/sisu.ut.ee\/wp-content\/plugins\/watupro\/img\/loading.gif\" width=\"16\" height=\"16\" alt=\"Loading...\" title=\"Loading...\">\u00a0Loading...\t<\/div>\n<\/div>\n\n<br>\n\t\n\t\t\t<div class=\"watupro_buttons flex \" id=\"watuPROButtons12\">\n\t\t  <div id=\"prev-question\" style=\"display:none;\"><input type=\"button\" value=\"&lt; Previous\" onclick=\"WatuPRO.nextQuestion(event, 'previous');\"><\/div>\t\t  \t\t  \t\t   \n\t\t   \t  \t\t<div><input type=\"button\" name=\"action\" class=\"watupro-submit-button\" onclick=\"WatuPRO.submitResult(event)\" id=\"action-button\" value=\"View Results\">\n\t\t<\/div>\n\t\t<\/div>\n\t\t\n\t<input type=\"hidden\" name=\"quiz_id\" value=\"12\" id=\"watuPROExamID\">\n\t<input type=\"hidden\" name=\"start_time\" id=\"startTime\" value=\"2026-04-17 19:59:36\">\n\t<input type=\"hidden\" name=\"start_timestamp\" id=\"startTimeStamp\" value=\"1776455976\">\n\t<input type=\"hidden\" name=\"question_ids\" value=\"\">\n\t<input type=\"hidden\" name=\"watupro_questions\" value=\"38:120,121,122 | 39: | 40:126,125,124 | 41:127\">\n\t<input type=\"hidden\" name=\"no_ajax\" value=\"0\">\t\t\t<\/form>\n\t<p>\u00a0<\/p>\n<\/div>\n\n<script type=\"text\/javascript\">\n\/\/jQuery(document).ready(function(){\ndocument.addEventListener(\"DOMContentLoaded\", function(event) { \t\nvar question_ids = \"38,39,40,41\";\nWatuPROSettings[12] = {};\nWatuPRO.qArr = question_ids.split(',');\nWatuPRO.exam_id = 12;\t    \nWatuPRO.post_id = 1185;\nWatuPRO.store_progress = 0;\nWatuPRO.curCatPage = 1;\nWatuPRO.requiredIDs=\"0\".split(\",\");\nWatuPRO.hAppID = \"0.71948200 1776445176\";\nvar url = \"https:\/\/sisu.ut.ee\/wp-content\/plugins\/watupro\/show_exam.php\";\nWatuPRO.examMode = 1;\nWatuPRO.siteURL=\"https:\/\/sisu.ut.ee\/lcms_method_validation\/wp-admin\/admin-ajax.php\";\nWatuPRO.emailIsNotRequired = 0;\nWatuPRO.perDecade = 10;\nWatuPROIntel.init(12);\nWatuPRO.inCategoryPages=1;});    \t \n<\/script>\n\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":60,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":""},"class_list":["post-1185","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/sisu.ut.ee\/lcms_method_validation\/wp-json\/wp\/v2\/pages\/1185","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sisu.ut.ee\/lcms_method_validation\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sisu.ut.ee\/lcms_method_validation\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sisu.ut.ee\/lcms_method_validation\/wp-json\/wp\/v2\/users\/60"}],"replies":[{"embeddable":true,"href":"https:\/\/sisu.ut.ee\/lcms_method_validation\/wp-json\/wp\/v2\/comments?post=1185"}],"version-history":[{"count":0,"href":"https:\/\/sisu.ut.ee\/lcms_method_validation\/wp-json\/wp\/v2\/pages\/1185\/revisions"}],"wp:attachment":[{"href":"https:\/\/sisu.ut.ee\/lcms_method_validation\/wp-json\/wp\/v2\/media?parent=1185"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}