CT2111

Stool: Clostridium difficile common antigen and toxin/toxin gene

CT2111A: Negative/Negative    CT2111B:Positive/Positive

CMPT QA/QC

CT2111-A: C.difficile common antigen negative and gene/toxin negative, viable for 35 days

CT2111-B: C.difficile common antigen positive and gene/toxin positive, viable for 35 days

Reference Laboratories

CT2111-A: 8/11 labs reported both antigen and toxin negative; two labs did not test antigen but reported toxin negative; one lab reported antigen indeterminate but tested negative for toxin.

CT2111-B: 9/11 labs reported both antigen and toxin positive; two labs did not test antigen but reported toxin positive.

Participants’ results

NOTE: grading for Clostridium difficile toxin testing has changed. Please click here for more details

(Insert table results A) 

Table 1. CT2111A - Antigen/Toxin or Toxin geneTotalGrade
negative/negative46Acceptable/Acceptable
not tested/negative6Ungraded/Acceptable
negative/not tested1Acceptable/Ungraded
indeterminate/negative1Ungraded/Acceptable
Total54

 

(Insert table results B) 

Table 1. CT2111B - Antigen/Toxin or Toxin geneTotalGrade
positive/positive47Acceptable/Acceptable
not tested/positive6Ungraded/Acceptable
indeterminate/indeterminate*1Ungraded/Ungraded
Total54

*Laboratory indicated they would refer sample for further tesing.

Insert table IC/PH B if applicable 

Table 2. CT2111B - IC /PH NotificationTotalGrade
YES52Acceptable
NO *1Ungraded
Not applicable (reported indeterminate)1Ungraded
Total54

*Lab is an outpatient laboratory and not required to report to Infection Control

Suitability for Grading

A challenge is considered suitable for grading if agreement is reached by 80 percent of selected reference group and at least 70 percent of the participants.

Antigen and toxin detection was correctly performed by at least 80 percent of reference laboratories and greater than 70 percent of all laboratories thus, both challenges were determined to be suitable for grading.

Grading: Please note that grading for Clostridium difficile toxin testing has changed. Please click here for more details

The samples are assessed for homogeneity and stability using in-house quality control methods and random selection of samples before and during production, and post sample delivery. The number of random samples selected is based on selection tables within Military standard 105E (1).

The challenge sample lot was confirmed to be homogeneous and stable for at least 15 days.

Grading of Clostridium difficile common antigen and toxin/toxin gene detection is based on a Positive / Negative result, no further statistical analysis is performed on the results beyond that described under “Suitability for grading(1) Famum NR. Acceptance sampling. In: Modern Statistical Quality Control and Improvement. Belmont, California.: Duxbury Press; 1994:305.

Stool: Clostridium difficile common antigen and toxin/toxin gene

CTxxxxA: Result/Result     CTxxxxB: Result/Result

CMPT QA/QC

CTxxxx-A: C.difficile common antigen result and gene/toxin result, viable for x days

CTxxxx-B: C.difficile common antigen result and gene/toxin result, viable for x days

Reference Laboratories

CTxxxx-A: 

CTxxxx-B: 

Participants’ results

NOTE: grading for Clostridium difficile toxin testing has changed. Please click here for more details

(Insert table results A) [table “x” not found /]

Insert table IC/PH A if applicable [table “x” not found /]

(Insert table results B) [table “x” not found /]

Insert table IC/PH B if applicable [table “x” not found /]

NT: not tested

Suitability for Grading

A challenge is considered suitable for grading if agreement is reached by 80 percent of selected reference group and at least 70 percent of the participants.

Antigen and toxin detection was correctly performed by at least 80 percent of reference laboratories and greater than 70 percent of all laboratories thus, both challenges were determined to be suitable for grading.

Grading: Please note that grading for Clostridium difficile toxin testing has changed. Please click here for more details

The samples are assessed for homogeneity and stability using in-house quality control methods and random selection of samples before and during production, and post sample delivery. The number of random samples selected is based on selection tables within Military standard 105E (1).

The challenge sample lot was confirmed to be homogeneous and stable for at least 15 days.

Grading of Clostridium difficile common antigen and toxin/toxin gene detection is based on a Positive / Negative result, no further statistical analysis is performed on the results beyond that described under “Suitability for grading(1) Famum NR. Acceptance sampling. In: Modern Statistical Quality Control and Improvement. Belmont, California.: Duxbury Press; 1994:305.

Posted in Clostridium difficile Results, critiques