Overall Table Statistics

Table 1: 15 November 2021 to 25 December 2021

Table 1: Overall HIV VL Invalid cases from the period 15 November 2021 to 23 December 2021
Characteristic N = 2,0531
Flag Type
CO2H1 30% (616 / 2,048)
P02T 1.7% (35 / 2,048)
P07P 0.5% (11 / 2,048)
Q02 63% (1,287 / 2,048)
U02T <0.1% (1 / 2,048)
U04 4.4% (90 / 2,048)
U06T 0.4% (8 / 2,048)
Flag Severity
Critical 97% (1,993 / 2,048)
Fatal 2.7% (55 / 2,048)
Flag Description
Clot has been detected while aspirating sample 1.7% (35 / 2,048)
Control batch was invalidated (control batch failed) 63% (1,287 / 2,048)
Data for target 1 cannot be analyzed 30% (616 / 2,048)
Insufficient volume was detected in sample tube, sample was not pipetted <0.1% (1 / 2,048)
Not enough supernatant was removed 0.5% (11 / 2,048)
Pipetted volume was not sufficient, sample was not transferred 0.4% (8 / 2,048)
Test order was cancelled by user 4.4% (90 / 2,048)

1 % (n / N)

Weekly Table Statistics

Table 1: 14 November 2021 to 20 November 2021

Table 2: HIV VL Invalid cases from the period 14 November 2021 to 20 November 2021
Characteristic N = 5811
Flag Type
CO2H1 1.0% (6 / 581)
P02T 0.5% (3 / 581)
P07P 0% (0 / 581)
Q02 98% (572 / 581)
U02T 0% (0 / 581)
U04 0% (0 / 581)
U06T 0% (0 / 581)
Flag Severity
Critical 99% (578 / 581)
Fatal 0.5% (3 / 581)
Flag Description
Clot has been detected while aspirating sample 0.5% (3 / 581)
Control batch was invalidated (control batch failed) 98% (572 / 581)
Data for target 1 cannot be analyzed 1.0% (6 / 581)
Insufficient volume was detected in sample tube, sample was not pipetted 0% (0 / 581)
Not enough supernatant was removed 0% (0 / 581)
Pipetted volume was not sufficient, sample was not transferred 0% (0 / 581)
Test order was cancelled by user 0% (0 / 581)

1 % (n / N)

Table 2: 21 November 2021 to 27 November 2021

Table 2: HIV VL Invalid cases from the period 21 November 2021 to 27 November 2021
Characteristic N = 351
Flag Type
CO2H1 66% (23 / 35)
P02T 29% (10 / 35)
P07P 5.7% (2 / 35)
Q02 0% (0 / 35)
U02T 0% (0 / 35)
U04 0% (0 / 35)
U06T 0% (0 / 35)
Flag Severity
Critical 66% (23 / 35)
Fatal 34% (12 / 35)
Flag Description
Clot has been detected while aspirating sample 29% (10 / 35)
Control batch was invalidated (control batch failed) 0% (0 / 35)
Data for target 1 cannot be analyzed 66% (23 / 35)
Insufficient volume was detected in sample tube, sample was not pipetted 0% (0 / 35)
Not enough supernatant was removed 5.7% (2 / 35)
Pipetted volume was not sufficient, sample was not transferred 0% (0 / 35)
Test order was cancelled by user 0% (0 / 35)

1 % (n / N)

Table 3: 28 November 2021 to 04 December 2021

Table 2: HIV VL Invalid cases from the period 28 November 2021 to 04 December 2021
Characteristic N = 921
Flag
CO2H1 83% (76 / 92)
P02T 8.7% (8 / 92)
P07P 2.2% (2 / 92)
Q02 0% (0 / 92)
U02T 0% (0 / 92)
U04 0% (0 / 92)
U06T 6.5% (6 / 92)
Flag_severity
Critical 83% (76 / 92)
Fatal 17% (16 / 92)
Flag_description
Clot has been detected while aspirating sample 8.7% (8 / 92)
Control batch was invalidated (control batch failed) 0% (0 / 92)
Data for target 1 cannot be analyzed 83% (76 / 92)
Insufficient volume was detected in sample tube, sample was not pipetted 0% (0 / 92)
Not enough supernatant was removed 2.2% (2 / 92)
Pipetted volume was not sufficient, sample was not transferred 6.5% (6 / 92)
Test order was cancelled by user 0% (0 / 92)

1 % (n / N)

Table 4: 05 December 2021 to 11 December 2021

Table 3: HIV VL Invalid cases from the period 05 December 2021 to 11 December 2021
Characteristic N = 2831
Flag Type
CO2H1 98% (276 / 283)
P02T 0.7% (2 / 283)
P07P 1.8% (5 / 283)
Q02 0% (0 / 283)
U02T 0% (0 / 283)
U04 0% (0 / 283)
U06T 0% (0 / 283)
Flag Severity
Critical 98% (276 / 283)
Fatal 2.5% (7 / 283)
Flag Description
Clot has been detected while aspirating sample 0.7% (2 / 283)
Control batch was invalidated (control batch failed) 0% (0 / 283)
Data for target 1 cannot be analyzed 98% (276 / 283)
Insufficient volume was detected in sample tube, sample was not pipetted 0% (0 / 283)
Not enough supernatant was removed 1.8% (5 / 283)
Pipetted volume was not sufficient, sample was not transferred 0% (0 / 283)
Test order was cancelled by user 0% (0 / 283)

1 % (n / N)

Table 5: 12 December 2021 to 18 December 2021

Table 3: HIV VL Invalid cases from the period 12 December 2021 to 18 December 2021
Characteristic N = 1461
Flag Type
CO2H1 91% (133 / 146)
P02T 6.8% (10 / 146)
P07P 0% (0 / 146)
Q02 0% (0 / 146)
U02T 0.7% (1 / 146)
U04 0% (0 / 146)
U06T 1.4% (2 / 146)
Flag Severity
Critical 91% (133 / 146)
Fatal 8.9% (13 / 146)
Flag Description
Clot has been detected while aspirating sample 6.8% (10 / 146)
Control batch was invalidated (control batch failed) 0% (0 / 146)
Data for target 1 cannot be analyzed 91% (133 / 146)
Insufficient volume was detected in sample tube, sample was not pipetted 0.7% (1 / 146)
Not enough supernatant was removed 0% (0 / 146)
Pipetted volume was not sufficient, sample was not transferred 1.4% (2 / 146)
Test order was cancelled by user 0% (0 / 146)

1 % (n / N)

Table 6: 20 December 2021 to 25 December 2021

Table 3: HIV VL Invalid cases from the period 20 December 2021 to 25 December 2021
Characteristic N = 1021
Flag Type
CO2H1 12% (12 / 102)
P02T 0% (0 / 102)
P07P 0% (0 / 102)
Q02 0% (0 / 102)
U02T 0% (0 / 102)
U04 88% (90 / 102)
U06T 0% (0 / 102)
Flag Severity
Critical 100% (102 / 102)
Fatal 0% (0 / 102)
Flag Description
Clot has been detected while aspirating sample 0% (0 / 102)
Control batch was invalidated (control batch failed) 0% (0 / 102)
Data for target 1 cannot be analyzed 12% (12 / 102)
Insufficient volume was detected in sample tube, sample was not pipetted 0% (0 / 102)
Not enough supernatant was removed 0% (0 / 102)
Pipetted volume was not sufficient, sample was not transferred 0% (0 / 102)
Test order was cancelled by user 88% (90 / 102)

1 % (n / N)

Overall Distribution: Plots

Plot 1: Overall Distribution

Fig 1: Overall distribution of HIV VL Invalid cases. The colours represent the various flag types generated by the Cobas 8800 instrument. The dotted lines depict the various dates, technologists observed and recorded a non-conforming event generated by the Cobas 8800 instrument.

My observations: Overall the most detected flag type was Q02 (control batch was invalidated (control batch failed)), followed by C02H1 (Data for target 1 cannot be analysed). High frequency of Q02 was observed on the 18th of November 2021 then faded away over the weeks as it was replaced by C02H1. High frequency of C02H1 was observed on the 10th of December 2021.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • Q02: Affects the entire batch
  • C02H1: Affects individual samples

Weekly Distribution: Plots

Plot 1: Period 14 November 2021 to 20 November 2021

Fig 1: Weekly distribution of HIV VL Invalid cases. The colours represent the various flag types generated by the Cobas 8800 instrument. The dotted lines depict the various dates, technologists observed and recorded a non-conforming event/s generated by the Cobas 8800 instrument.

My observations: the most detected flag type was Q02 (control batch was invalidated (control batch failed)), followed by C02H1 (Data for target 1 cannot be analysed). The 18th of November 2021, had the highest frequency of invalid cases.

Notes from technologist in-charge: On the 15th of November 2021, a concern with the instruments transfer module was recorded. On the 18th of November 2021, the technologist in-charge (day shift), noted a rise in failing runs and requested a call to be logged to Roche personnel.

On the 19th of November 2021, another technologist in-charge noted more errors (tranfer module, firmware motion control, software error) including technical instrument problems and documented them.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • Q02: Affects the entire batch
  • C02H1: Affects individual samples

Plot 2: Period 21 November 2021 to 27 November 2021

Fig 2: Weekly distribution of HIV VL Invalid cases. The colours represent the various flag types generated by the Cobas 8800 instrument. The dotted lines depict the various dates, technologists observed and recorded a non-conforming event/s generated by the Cobas 8800 instrument.

My observations: Overall the most detected flag type was C02H1 (Data for target 1 cannot be analysed) followed by P02T (Clot has been detected while aspirating sample). The 25th of November 2021, had the highest frequency of invalid cases.

Notes from technologist in-charge: On the 23rd of November 2021, more technologists in-charge, were witnessing more errors generated by the Cobas 8800 instrument. Another request to log a call to Roche was made but there seemed to be a problem with their priority/emergency line.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • C02H1: Affects individual samples
  • P02T: Affects individual samples

Plot 3: Period 28 November 2021 to 03 November 2021

Fig 3: Weekly distribution of HIV VL Invalid cases. The colours represent the various flag types generated by the Cobas 8800 instrument. The dotted lines depict the various dates, technologists observed and recorded a non-conforming event/s generated by the Cobas 8800 instrument.

My observations (plot): Overall the most detected flag type was C02H1 (Data for target 1 cannot be analysed), followed by P02T (Clot has been detected while aspirating sample) and U06T (Pipetted volume was not sufficient, sample was not transferred). The 2nd of December 2021, had the highest frequency of invalid cases, followed by the the 1st of December 2021.

Notes from technologist in-charge: On the 2nd of December 2021, technical instrument problems were observed and recorded (Samples not being pulled to the scanner).

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • C02H1: Affects individual samples
  • P02T: Affects individual samples

Plot 4: Period 05 December 2021 to 11 December 2021

Fig 4: Weekly distribution of HIV VL Invalid cases. The colours represent the various flag types generated by the Cobas 8800 instrument. The dotted lines depict the various dates, technologists observed and recorded a non-conforming event/s generated by the Cobas 8800 instrument.

My observations (plot): Overall the most detected flag type was C02H1 (Data for target 1 cannot be analysed), followed by P07P (Not enough supernatant was removed). The 10th of December 2021, had the highest frequency of invalid cases, followed by the the 07th of December 2021.

Notes from technologist in-charge: No notes were recorded by the technologist in-charge on this week.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • C02H1: Affects individual samples
  • P07P: Affects individual samples

Plot 5: Period 12 December 2021 to 18 December 2021

Fig 5: Weekly distribution of HIV VL Invalid cases. The colours represent the various flag types generated by the Cobas 8800 instrument. The dotted lines depict the various dates, technologists observed and recorded a non-conforming event/s generated by the Cobas 8800 instrument.

My observations (plot): Overall the most detected flag type was C02H1 (Data for target 1 cannot be analysed), followed by P02T (Clot has been detected while aspirating sample). The 12th of December 2021, had the highest frequency of invalid cases, followed by the 18th of December 2021.

Notes from technologist in-charge: On the 13th of December 2021, the technologist in-charge (night shift), decided to mask (inactivate) the instruments analytical A1 and A2 units because of the high frequency of C02H1. A Roche personnel (Sekgaila) was notified about the action. Another technologist in-charge (day shift), noted to have checked the errors and the problem seemed to be Module A not the analytical units. Module A was masked and Module B was used, this decision was communicated with Roche personnel (Avi).

On the 14th of December 2021, a call was logged for the errors. Steven (Roche) arrived, “the problem is identified as the channel beads that have been leaking either on top of the plates or on the platform. Parts are ordered and will be collected tonight. Replacement due tomorrow morning”. Module A is still masked.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • C02H1: Affects individual samples
  • P02T: Affects individual samples

Plot 6: Period 19 December 2021 to 25 December 2021

Fig 6: Weekly distribution of HIV VL Invalid cases. The colours represent the various flag types generated by the Cobas 8800 instrument. The dotted lines depict the various dates, technologists observed and recorded a non-conforming event/s generated by the Cobas 8800 instrument.

My observations (plot): Overall the most detected flag type was U04 (Test order was cancelled by user), followed by C02H1 (Data for target 1 cannot be analysed). The 20th of December 2021, had the highest frequency of invalid cases.

Notes from technologist in-charge: On the 20th of December 2021, the lab manager, spoke with Roche personnel regarding the high frequency of C02H1 observed on the 18th of December 2021. Documents of HIV VL invalid cases were emailed to the Roche personnel.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • U04: Affects the entire batch
  • C02H1: Affects individual samples

Bar Plots with Statistics (Date of creation)

Plot 1: Period 14 November 2021 to 20 November 2021

Plot 1: The most detected flag type was Q02 (control batch was invalidated (control batch failed)), followed by C02H1 (Data for target 1 cannot be analysed). The 18th of November 2021, had the highest frequency of invalid cases.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • Q02: Affects the entire batch
  • C02H1: Affects individual samples

Plot 2: Period 21 November 2021 to 27 November 2021

Plot 2: Overall the most detected flag type was C02H1 (Data for target 1 cannot be analysed) followed by P02T (Clot has been detected while aspirating sample). The 25th of November 2021, had the highest frequency of invalid cases.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • C02H1: Affects individual samples
  • P02T: Affects individual samples

Plot 3: Period 28 November 2021 to 04 December 2021

Plot 3: Overall the most detected flag type was C02H1 (Data for target 1 cannot be analysed), followed by P02T (Clot has been detected while aspirating sample) and U06T (Pipetted volume was not sufficient, sample was not transferred). The 2nd of December 2021, had the highest frequency of invalid cases, followed by the the 1st of December 2021.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • C02H1: Affects individual samples
  • P02T: Affects individual samples

Plot 4: Period 05 December 2021 to 11 December 2021

Plot 4: Overall the most detected flag type was C02H1 (Data for target 1 cannot be analysed), followed by P07P (Not enough supernatant was removed). The 10th of December 2021, had the highest frequency of invalid cases, followed by the the 07th of December 2021.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • C02H1: Affects individual samples
  • P07P: Affects individual samples

Plot 5: Period 12 December 2021 to 18 December 2021

Plot 5: Overall the most detected flag type was C02H1 (Data for target 1 cannot be analysed), followed by P02T (Clot has been detected while aspirating sample). The 12th of December 2021, had the highest frequency of invalid cases, followed by the the 18th of December 2021.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • C02H1: Affects individual samples
  • P02T: Affects individual samples

Plot 6: Period 20 December 2021 to 23 December 2021

Plot 6: Overall the most detected flag type was U04 (Test order was cancelled by user), followed by C02H1 (Data for target 1 cannot be analysed). The 20th of December 2021, had the highest frequency of invalid cases.

Note: If a batch (93 samples and 2 positive controls and 1 negative control) is invalid, repeat testing of the entire batch including samples and controls.

  • U04: Affects the entire batch
  • C02H1: Affects individual samples

Bar Plots with Statistics (Time of creation)

Plot 1: Period 14 November 2021 to 20 November 2021

Plot 2: Period 21 November 2021 to 28 November 2021

Plot 3: Period 28 November 2021 to 04 December 2021

Plot 4: Period 05 December 2021 to 11 December 2021

Plot 5: Period 12 December 2021 to 18 December 2021

Plot 6: Period 20 December 2021 to 23 December 2021