natgillin/translations-raw huggingface dataset:
Screeningens målkoncentration (STC): Den relevante koncentration for påvisning af mykotoksinet i en prøve.
Numeric values to be used for α as constant in formula set out in this point, depending on the concentration of interest
Når målet er at teste overensstemmelsen med forskrevne grænseværdier, svarer STC til den gældende grænseværdi.
C (μg/kg)
Til andre formål, eller såfremt der ikke er fastsat nogen grænseværdi, prædefinerer laboratoriet STC.
Ref: M. Thompson and R. Wood, Accred.
Screeningsmetode: Metode, der anvendes ved udvælgelse af prøver med et mykotoksinindhold, der med et vist konfidensniveau overstiger screeningens målkoncentration (STC).
Assur., 2006, 10, p.
For så vidt angår mykotoksinscreening anses et konfidensniveau på 95 % for at være egnet.
471-478.
Resultatet af screeningsanalysen er enten »negativ« eller »mistænkt«.
Specific requirements for semi-quantitative screening methods
Screeningsmetoder giver mulighed for omkostningseffektivitet og høj produktivitet med hensyn til antallet af screenede prøver, hvilket forbedrer mulighederne for at opdage nye hændelser med høj eksponering og sundhedsrisici for forbrugerne.
Scope
Disse metoder baseres på bioanalytiske metoder, LC-MS- eller HPLC-metoder.
The scope applies to bioanalytical methods based on immuno-recognition or receptor binding (such as ELISA, dip-sticks, lateral flow devices, immuno-sensors) and physicochemical methods based on chromatography or direct detection by mass spectrometry (e.g. ambient MS).
Resultater fra prøver, der overstiger afskæringsværdien, skal verificeres ved en fuldstændig fornyet analyse fra den originale prøve ved hjælp af en verifikationsmetode.
Other methods (e.g. thin layer chromatography) are not excluded provided the signals generated relate directly to the mycotoxins of interest and allow that the principle described hereunder is applicable.
»Negativ prøve« betyder, at mykotoksinindholdet i prøven er < STC med et konfidensniveau på 95 % (dvs. der er 5 % risiko for, at prøven fejlagtigt indberettes som negativ).
The specific requirements apply to methods of which the result of the measurement is a numerical value, for example a (relative) response from a dip-stick reader, a signal from LC-MS, etc., and that normal statistics apply.
»Falsk negativ prøve« betyder, at mykotoksinindholdet i prøven er > STC, men at prøven er blevet identificeret som negativ.
The requirements do not apply to methods that do not give numerical values (e.g. only a line that is present or absent), which require different validation approaches.
»Mistænkt prøve« (positiv screening) betyder, at prøven overstiger afskæringsværdien (se nedenfor), og at mykotoksinniveauet kan være højere end STC.
Specific requirements for these methods are provided in point 4.3.3.
Et hvert mistænkt resultat udløser en verifikationsanalyse til utvetydig identifikation og kvantificering af mykotoksin.
This document describes procedures for the validation of screening methods by means of an inter-laboratory validation, the verification of the performance of a method validated by means of an inter-laboratory exercise and the single-laboratory validation of a screening method.
»Falsk mistænkt prøve« er en negativ prøve, der er blevet identificeret som mistænkt.
Terminology
Ved »verifikationsmetoder« forstås metoder, der giver fuldstændige eller supplerende oplysninger, så mykotoksinet kan identificeres og kvantificeres entydigt på det relevante niveau.
Screening target concentration (STC): the concentration of interest for detection of the mycotoxin in a sample.
Afskæringsværdi: Den respons, det signal eller den koncentration, som opnås ved screeningsmetoden, over hvilke prøven klassificeres som »mistænkt«.
When the aim is to test compliance with regulatory limits, the STC is equal to the applicable maximum level.
Afskæringen bestemmes ved valideringen og tager hensyn til målingens variabilitet.
For other purposes or in case no maximum level has been established, the STC is predefined by the laboratory.
Negativ kontrolprøve (blind-matrix): En prøve, som vides at være fri [1] for det mykotoksin, som der screenes for, dvs. på baggrund af tidligere konstatering ved brug af en verifikationsmetode, der er tilstrækkelig følsom.
Screening method: means method used for selection of those samples with levels of mycotoxins that exceed the screening target concentration (STC), with a given certainty.
Hvis der ikke kan indsamles nogen blindprøver, kan der muligvis anvendes materiale med det lavest tilgængelige niveau, så længe det på baggrund af niveauet er muligt at komme frem til den konklusion, at screeningsmetoden er egnet.
For the purpose of mycotoxin screening, a certainty of 95 % is considered fit-for-purpose.
Positiv kontrolprøve: Prøve, der indeholder mykotoksinet på samme niveau som screeningens målkoncentration, f.eks. et certificeret referencemateriale, materiale med kendt indhold (f.eks. testmateriale fra præstationsprøvninger) eller på anden måde tilstrækkelig defineret af en verifikationsmetode.
The result of the screening analysis is either “negative” or “suspect”.
Hvis der ikke foreligger nogen af ovenstående, kan man anvende en blanding af prøver med forskellige kontaminationsniveauer eller en spiket prøve, der er fremstillet i et laboratorium, og som er tilstrækkelig defineret, såfremt det kan bevises, at kontaminationsniveauet er blevet verificeret.
Screening methods shall allow a cost-effective high sample-throughput, thus increasing the chance to discover new incidents with high exposure and health risks to consumers.
Valideringsprocedure
These methods shall be based on bio-analytical, LC-MS or HPLC methods.
Målet med valideringen er at vise screeningsmetodens egnethed.
Results from samples exceeding the cut-off value shall be verified by a full re-analysis from the original sample by a confirmatory method.
Screeningsmetoder kan valideres af flere laboratorier eller ét enkelt laboratorium.
“Negative sample” means the mycotoxin content in the sample is < STC with a certainty of 95 % (i.e. there is a 5 % chance that samples will be incorrectly reported as negative).
Hvis der allerede foreligger valideringsdata fra flere laboratorier for en vis kombination af mykotoksin/matrix/STC, er det tilstrækkeligt, at metodens pålidelighed kontrolleres i et laboratorium, der anvender metoden.
“False negative sample” means the mycotoxin content in the sample is > STC but it has been identified as negative.
Første validering ved validering af ét enkelt laboratorium
“Suspect sample” (screen positive) means the sample exceeds the cut-off level (see below) and may contain the mycotoxin at a level higher than the STC.
Mykotoksiner:
Any suspect result triggers a confirmatory analysis for unambiguous identification and quantification of the mycotoxin.
Der skal udføres validering for hvert enkelt mykotoksin inden for anvendelsesområdet.
“False suspect sample” is a negative sample that has been identified as suspect.
I forbindelse med bioanalytiske metoder, der giver en kombineret respons for en vis mykotoksingruppe (dvs. aflatoksin B1, B2, G1 & G2, fumonisin B1 & B2), skal anvendeligheden bevises, og testens begrænsninger skal nævnes inden for metodens anvendelsesområde.
“Confirmatory methods” means methods that provide full or complementary information enabling the mycotoxin to be identified and quantified unequivocally at the level of interest.
Matrixer:
Cut-off level: the response, signal, or concentration, obtained with the screening method, above which the sample is classified as “suspect”.
Der bør gennemføres en indledende validering for hver enkel vare eller for hver varegruppe, hvis metoden vides at kunne anvendes på flere varer.
The cut-off is determined during the validation and takes the variability of the measurement into account.
I dette tilfælde udvælges der en repræsentativ og en relevant vare fra den gruppe (se tabel A).
Negative control (blank matrix) sample: a sample known to be free [1] of the mycotoxin to be screened for, e.g. by previous determination using a confirmatory method of sufficient sensitivity.
Prøvesæt:
If no blank samples can be obtained, then material with the lowest obtainable level might be used as long as the level allows the conclusion that the screening method is fit for purpose.Positive control sample: sample containing the mycotoxin at the screening target concentration, e.g. a certified reference material, a material of known content (e.g. test material of proficiency tests) or otherwise sufficiently characterised by a confirmatory method.
Til valideringssættet kan der eventuelt tilføjes yderligere sæt bestående af 20 prøver, der indeholder mykotoksinet på andre niveauer, med henblik på at få kendskab til, i hvilket omfang metoden kan skelne mellem forskellige mykotoksinkoncentrationer.
Validation procedure
Koncentration:
The aim of the validation is to demonstrate the fitness of purpose of the screening method.
For hver STC, der anvendes i en rutinemæssig undersøgelse, skal der gennemføres en validering.
This is done by determination of the cut-off value and determination of the false negative and false suspect rate.
Indledende validering ved fællesafprøvning
In these two parameters performance characteristics such as sensitivity, selectivity, and precision are embedded.
Validering ved fællesafprøvning skal udføres i henhold til en international anerkendt protokol om fællesafprøvninger (f.eks. ISO 5725:1994 eller IUPAC International Harmonised Protocol), som forudsætter, at der inddrages gyldige data fra mindst otte forskellige laboratorier.
Screening methods can be validated by inter-laboratory or by single laboratory validation.
Derudover er den eneste forskel sammenlignet med validering i ét enkelt laboratorium, at de ≥ 20 prøver pr. vare/indhold kan fordeles ligeligt mellem de deltagende laboratorier med mindst to prøver pr. laboratorium.
If inter-laboratory validation data is already available for a certain mycotoxin/matrix/STC combination, a verification of method performance is sufficient in a laboratory implementing the method.
De (relative) responser fra de negative og positive kontrolprøver anvendes som grundlag for beregningen af de påkrævede parametre.
Mycotoxins:
Screeningsmetoder med en respons proportional med mykotoksinkoncentrationen
The validation shall be performed for every individual mycotoxin in the scope.
For så vidt angår screeningsmetoder med en respons proportional med mykotoksinkoncentrationen gælder følgende:
In case of bio-analytical methods that give a combined response for a certain mycotoxin group (e.g. aflatoxins B1, B2, G1 & G2; fumonisins B1 & B2), applicability must be demonstrated and limitations of the test mentioned in the scope of the method.
Afskæring = RSTC – t-værdi0,05 * SDSTC
Undesired cross-reactivity (e.g. DON-3-glycoside, 3- or 15-acetyl-DON for immuno-based methods for DON) is not considered to increase the false negative rate of the target mycotoxins, but may increase the false suspect rate.
respons fra de positive kontrolprøver (på STC-niveau)
This unwanted increasing will be diminished by confirmatory analysis for unambiguous identification and quantification of the mycotoxins.
t-værdi = ensidet t-værdi for en andel af falsk negative resultater på 5 % (se tabel B)
Matrices:
standardafvigelse
An initial validation should be performed for each commodity, or, when the method is known to be applicable to multiple commodities, for each commodity group.
Screeningsmetoder med en respons omvendt proportional med mykotoksinkoncentrationen
In the latter case, one representative and relevant commodity is selected from that group (see table A).
Lignende for screeningsmetoder med en respons omvendt proportional med mykotoksinkoncentrationen fastlægges afskæringen som:
Sample set:
Afskæring = RSTC + t-værdi0,05 * SDSTC
The minimum number of different samples required for validation is 20 homogeneous negative control samples and 20 homogeneous positive control samples that contain the mycotoxin at the STC, analysed under intermediate precision (RSDRi) conditions spread over 5 different days.
Ved at anvende denne specifikke t-værdi til at fastlægge afskæringsværdien er andelen af falsk negative resultater automatisk fastsat til 5 %.
Optionally, additional sets of 20 samples containing the mycotoxin at other levels can be added to the validation set to gain insight to what extent the method can distinguish between different mycotoxin concentrations.
Vurdering af egnethed
Concentration:
t-værdi (afskæring — middelværdiblindprøve)/SDblindprøve
For each STC to be used in routine application, a validation has to be performed.
ved screeningsmetoder med en respons proportional med mykotoksinkoncentrationen
Initial validation through collaborative trials
t-værdi (middelværdiblindprøve — afskæring)/SDblindprøve
Validation through collaborative trials shall be done in accordance with an internationally recognised protocol on collaborative trials (e.g. ISO 5725:1994 or the IUPAC International Harmonised Protocol) which requires inclusion of valid data from at least eight different laboratories.
ved screeningsmetoder med en respons omvendt proportional med mykotoksinkoncentrationen.
Other than that, the only difference compared to single laboratory validations is that the ≥ 20 samples per commodity/level can be evenly divided over the participating laboratories, with a minimum of two samples per laboratory.
Fra den fremkomne t-værdi, baseret på frihedsgrader beregnet ud fra antal forsøg, kan sandsynligheden for falsk mistænkte prøver for så vidt angår ensidet fordeling enten beregnes (dvs. i form af regneark »TDIST«) eller tages fra en tabel over t-fordeling.
Determination of cut-off level and rate of false suspected results of blank samples
Den tilsvarende værdi for den ensidede t-fordeling specificerer andelen af falsk mistænkte resultater.
The (relative) responses for the negative control and positive control samples are taken as basis for the calculation of the required parameters.
Dette er beskrevet nærmere med et eksempel i »Analytical and Bioanalytical Chemistry DOI 10.1007/s00216 -013-6922-1«.
Screening methods with a response proportional with the mycotoxin concentration
Udvidelse af metodens anvendelsesområde
For screening methods with a response proportional with the mycotoxin concentration the following applies:
Udvidelse af anvendelsesområdet til andre mykotoksiner
Cut-off = RSTC – t-value0,05 * SDSTC
Når der tilføjes nye mykotoksiner til en eksisterende screeningsmetodes anvendelsesområde, er en fuldstændig validering påkrævet for at bevise metodens egnethed.
mean response of the positive control samples (at STC)
Udvidelse til andre varer
t-value: one tailed t-value for a rate of false negative results of 5 % (see table B)
Hvis screeningsmetoden vides eller forventes at blive anvendt til andre varer, skal disse andre varers validitet verificeres.
standard deviation
Hertil skal mindst 10 homogene negative og 10 homogene positive kontrolprøver (på STC-niveau) analyseres under intermediære præcisionsbetingelser.
Similarly, for screening methods with a response inversely proportional with the mycotoxin concentration, the cut-off is determined as:
De positive kontrolprøver skal ligge over afskæringsværdien.
Cut-off = RSTC + t-value0,05 * SDSTC
Hvis dette kriterium ikke opfyldes, er en fuldstændig validering påkrævet.
By using this specific t-value for establishing the cut-off value, the rate of false negative results is by default set at 5 %.
Kontrol af metoder, der allerede er valideret ved fællesafprøvninger
Fitness for purpose assessment
For så vidt angår screeningsmetoder, der allerede er blevet valideret ved en fællesafprøvning i et laboratorium, skal pålideligheden valideres.
Results from the negative control samples are used to estimate the corresponding rate of false suspect results.
Hertil skal mindst 6 negative og 6 positive kontrolprøver (på STC-niveau) analyseres.
The t-value is calculated corresponding to the event that a result of a negative control sample is above the cut off value, thus erroneously classified as suspect.
Hvis dette kriterium ikke opfyldes, skal laboratoriet analysere de grundlæggende årsager med henblik på at fastslå, hvorfor det ikke kan opfylde de krav, der blev fastlagt i fællesafprøvningen.
t-value (cut off – meanblank)/SDblank
Kun når laboratoriet har truffet korrigerende foranstaltninger skal det igen verificere metodens pålidelighed i sit laboratorium.
for screening methods with a response proportional with the mycotoxin concentration
Hvis laboratoriet ikke kan verificere resultaterne fra fællesafprøvningen, skal det fastlægge sin egen afskæring ved en fuldstændig validering i ét enkelt laboratorium.
t-value (meanblank – cut off)/SDblank
Kontinuerlig metodekontrol/løbende metodevalidering
for screening methods with a response inversely proportional with the mycotoxin concentration
Efter den indledende validering er yderligere valideringsdata nødvendige, idet der medtages mindst to positive kontrolprøver i hvert parti af screenede prøver.
From the obtained t-value, based on the degrees of freedom calculated from the number of experiments, the probability of false suspect samples for a one tailed distribution can either be calculated (e.g.. spread sheet function “TDIST”) or taken from a table for t-distribution.
Den ene positive kontrolprøve er en kendt prøve (dvs. en, der er anvendt i den indledende validering), den anden omfatter en anden vare fra samme varegruppe (hvis kun én vare analyseres, anvendes en anden prøve af denne vare i stedet for).
The corresponding value of the one tailed t-distribution specifies the rate of false suspect results.
Det er valgfrit, om der medtages negative kontrolprøver.
This concept is described in detail with an example in Analytical and Bioanalytical Chemistry DOI 10.1007/s00216 -013-6922-1.
Resultaterne fra de to positive kontrolprøver føjes til det eksisterende valideringssæt.
Extension of the scope of the method
Mindst én gang årligt fastlægges afskæringsværdien på ny, og metodens gyldighed revurderes.
Extension of scope to other mycotoxins:
Den kontinuerlige metodekontrol tjener flere formål:
When new mycotoxins are added to the scope of an existing screening method, a full validation is required to demonstrate the suitability of the method.
kvalitetskontrol af partiet af screenede prøver
Extension to other commodities:
formidling af oplysninger om metodens robusthed i henhold til det laboratories betingelser, der anvender metoden
If the screening method is known or expected to be applicable to other commodities, the validity to these other commodities shall be verified.
begrundelse for at anvende metoden på andre varer
As long as the new commodity belongs to a commodity group (see Table A) for which an initial validation has already been performed, a limited additional validation is sufficient.
mulighed for at justere afskæringsværdier i tilfælde af gradvise afvigelser i tidens løb.
For this, a minimum of 10 homogeneous negative control and 10 homogeneous positive control (at STC) samples shall be analysed under intermediate precision conditions.
Valideringsrapport
The positive control samples shall all be above the cut-off value.
Valideringsrapporten skal indeholde:
In case this criterion is not met, a full validation is required.
Angivelse af STC
Verification of methods already validated through collaborative trials
Angivelse af den fastlagte afskæring
For screening methods that have already been successfully validated through a collaborative laboratory trial, the method performance shall be verified.
Bemærk: Afskæringen skal have samme antal betydende cifre som STC.
For this a minimum of 6 negative control and 6 positive control (at STC) samples shall be analysed.
Numeriske værdier, der anvendes til at beregne afskæringen, skal have mindst ét betydende ciffer mere end STC.
In case this criterion is not met, the laboratory has to perform a root-cause analysis to identify why it cannot meet the specification as obtained in the collaborative trial.
Angivelse af den beregnede andel af falsk mistænkt
Only after taking corrective action it shall re-verify the method performance in its laboratory.
Angivelse af, hvordan andelen af falsk mistænkt er fremkommet.
In case the laboratory is not capable to verify the results from the collaborative trial, it will need to establish its own cut-off in a complete single laboratory validation.
Bemærk: Angivelsen af den beregnede andel af falsk mistænk indikerer, om metoden er egnet, da den indikerer antallet af blinde (eller ringe kontaminerede) prøver, som verificeres.
Continuous method verification/on-going method validation
Skema A
After initial validation, additional validation data are acquired by including at least two positive control samples in each batch of samples screened.
Varegruppe til valideringen af screeningsmetoder
One positive control sample is a known sample (e.g. one used during initial validation), the other is a different commodity from the same commodity group (in case only one commodity is analysed, a different sample of that commodity is used instead).
Varegrupper
Inclusion of a negative control sample is optional.
Varekategorier
The results obtained for the two positive control samples are added to the existing validation set.
Typiske repræsentative varer i kategorien
At least once a year the cut-off value is re-established and the validity of the method is re-assessed.
Højt vandindhold
The continuous method verification serves several purposes:
Frugtsaft
quality control for the batch of samples screened
Æblesaft, druesaft
providing information on robustness of the method at conditions in the laboratory that applies the method
Alkoholholdige drikkevarer
justification of applicability of the method to different commodities
Vin, øl, cider
allowing to adjust cut-off values in case of gradual drifts over time.
Rod- og knoldgrøntsager
Validation report
Frisk ingefær
The validation report shall contain:
Puré baseret på korn eller frugt
A statement on the STC
Puré til spædbørn eller småbørn
A statement on the obtained cut-off.
Højt olieindhold
Note: The cut-off must have the same number of significant figures as the STC.
Trænødder
Numerical values used to calculate the cut-off need at least one more significant figure than the STC.
Valnød, hasselnød, kastanje
A statement on calculated false suspected rate
Olieholdige frø og produkter heraf
A statement on how the false suspected rate was generated.
Rapsfrø, solsikkefrø, bomuldsfrø, sojabønner, jordnødder, sesam osv.
Note: The statement on the calculated false suspected rate indicates if the method is fit-for-purpose as it indicates the number of blank (or low level contamination) samples that will be subject to verification.
Olieholdige frugter og produkter heraf
Table A
Olier og pasta (dvs. jordnøddesmør, tahin)
Commodity groups for the validation of screening methods
Højt indhold af stivelse og/eller proteiner og lavt indhold af vand og fedt
Commodity groups
Kerner af korn og produkter heraf
Commodity categories
Hvede, rug, byg, majs, ris, havre Fuldkornsbrød, hvedebrød, kiks, morgenmadscerealier, pasta
Typical representative commodities included in the category
Diætetiske produkter
High water content
Pulver til forberedelse af mad til spædbørn eller småbørn
Fruit Juices
Højt syreindhold og højt vandindhold [2]
Apple juice, grape juice
Citrusprodukter
Alcoholic beverages
»Vanskelige eller unikke varer« [3]
Wine, beer, cider
Kakaobønner og produkter heraf, kopra og produkter heraf
Root and tuber vegetables
kaffe, te
Fresh ginger
Krydderier, lakrids
Cereal or fruit based purees
Højt sukkerindhold, lavt vandindhold
Purees intended for infants and small children
Tørrede frugter
High oil content
Figner, rosiner, korender, sultanas
Tree nuts
Mælk og mejeriprodukter
Walnut, hazelnut, chestnut
Mælk
Oil seeds and products thereof
Ko-, gede- og bøffelmælk
Oilseed rape, sunflower, cotton-seed, soybeans, peanuts, sesame etc.
Ost
Oily fruits and products thereof
Ko-, gedeost
Oils and pastes (e.g. peanut butter, tahina)
Mejeriprodukter (f.eks. mælkepulver)
High starch and/or protein content and low water and fat content
Yoghurt, fløde
Cereal grain and products thereof
Tabel B
Wheat, rye, barley, maize, rice, oats Wholemeal bread, white bread, crackers, breakfast cereals, pasta