cobas® liat system support: FAQ

Q: What are the recommended environmental operating conditions for the cobas® liat system?

A: Temperature range of 15-32°C (59-90°F), relative humidity of 15-80% (non-condensing), and altitude ≤ 2,000m (6,500 feet) above sea level.

Q: What are the placement requirements when installing the analyzer? 

A: Place the analyzer on a level, vibration free and non-reflective surface; away from direct sunlight. Allow at least 10 cm (4 inches) of space at the rear of the analyzer for airflow. Ensure the vents are not blocked. Allow at least 6 cm (2.5 inches) of space in front of the analyzer for easy barcode scanning. Position the analyzer near a grounded main outlet to avoid creating a trip hazard with the power cable.

Q: Are the cobas® liat system assays CLIA waived?

A: The cobas Cdiff assay is not CLIA Waived. All other cobas® liat system assays are CLIA Waived. A Certificate of Waiver is required to perform this testing in a CLIA Waived setting. To obtain CLIA Waiver information and a Certificate of Waiver, please contact your state health department.

Q: What is the difference between User, Supervisor and Administrator roles?

A: Users: Run authorized assays and view assay tube lots. Add assay tube lots. Change own password and badge barcode.

Supervisors: all User permitted actions, plus: review results, manage users (with user role supervisor or user), set up the analyzer (except network settings), configure data collection, manage assay tube lots, install assays, schedule tasks, archive and delete data, export data, import assay tube lots, back up analyzer, manage problem reports, clean USB flash drives.

Administrators: all Supervisor permitted actions, plus: network configuration settings, manage all users, update assays and software, register assays and software, import settings and users, restore analyzer.

Q: What printers are compatible with my cobas® liat system?

A: Please refer to the Printer Setup section of the cobas® liat system User Guide for detailed information on compatible printers and printer configuration. The cobas® liat system User Guide can be found under Guides and Documentation > User Guides..

Q: How do I restore or synchronize assay tube lots from one cobas® liat system to another using a USB flash drive? And, what is the difference between replacing and merging assay tube lots?

A: To restore or to synchronize assay tube lots, export the assay tube lots from an analyzer onto a USB flash drive, and then import the assay tube lots from the USB flash drive to a different analyzer.

To export assay tube lots to a USB flash drive, Choose Tools > Export data > Export assay lots.

If there is already an export file present on the USB flash drive, do one of the following:

• To replace the export file, choose the Replace button. Selecting Replace will overwrite the existing lot list on the USB flash drive.
• To merge the export file, choose the Merge button. No lots will be removed from the USB flash drive or instrument when selecting merge. The lot list from the instrument and USB flash drive will be combined.

Note: After removing expired assay tube lots from your cobas® liat system, you should Replace the export file on your USB flash drive.

To import assay tube lots, Choose Tools > Import data > Import assay lots. Enter your password and choose the Enter button.

Replace or merge the assay tube lots on the analyzer.

• To replace the lot list on the analyzer with the lot list on the USB flash drive, choose the Replace button.
• To merge the lot lists on the analyzer and USB flash drive, choose the Merge button. No lots will be removed from the USB flash drive or instrument when selecting merge. The lot list from the instrument and USB flash drive will be combined.

On the success message, choose the Confirm button, then remove the USB flash drive.

Q: What is the required user maintenance for the cobas® liat system?

A: The user is not required to perform any maintenance, other than touch screen calibration.

Q: Does the analyzer require service from a Roche service engineer?

A: The analyzer does not require service from a Roche service engineer.

Please note that the 5 year maintenance plan is no longer required for systems that have been upgraded to cobas® liat system software version 3.3 and higher. If you see a message on your analyzer regarding 5 year maintenance, please contact Roche cobas® liat system Technical Support at 1-800-800-5973.

Q: How should I clean the touch screen?

A: Keep the touch screen clean from excessive fingerprints and moisture by gently wiping it with a soft, lint-free cloth. Do not use isopropanol or bleach to clean the touch screen.

Q: How should I clean the exterior of the analyzer, and front buttons?

A: Do not spray or apply liquid directly on the analyzer or the power supply. Spraying or applying liquid to the analyzer or the power supply may damage the analyzer or pose an electrical hazard.

The exterior of the analyzer and front buttons can be cleaned using a soft, lint-free cloth moistened with either 70% isopropanol or 5-10% bleach solution. If bleach is used, the analyzer must then be wiped twice using a fresh lint-free cloth moistened with 70% isopropanol to remove all bleach residue. Periodically check the rear vent and bottom of the analyzer for excessive dust or debris. 

Q: How should I clean the window of the barcode reader?

A: Shut down the analyzer. Moisten a lint-free cloth with 70% isopropanol and then gently wipe the outside of the barcode reader window.

Only clean the window of the barcode reader in case of repeated barcode reading failures. DO NOT use bleach to clean the window of the barcode reader.

Q: When should I use the cleaning tool on my analyzer?

A: Only use the cleaning tool when prompted by the message “Use cleaning tool” on the screen. Use the provided cleaning tool, following the instructions provided in the Cleaning Tool Guide included with the cleaning tool kit. 

DO NOT use the cleaning tool for biological contamination. This tool does not decontaminate the analyzer, but becomes contaminated itself. If you suspect a tube leak happened inside the analyzer, contact Roche cobas® liat system Technical Support at 1-800-800-5973.

Q: What are the appropriate shipping conditions for the cobas® liat Assay kits?

A: 0°C to ≤ 35°C (32°F to 95°F), maximum 5 day transport time for the cobas CT/NG and cobas CT/NG/MG Assay kits

-20°C to ≤ 35°C (-4°F to 95°F), maximum 5 day transport time for all other cobas liat Assay kits

Depending on the season and/or geographic location, ambient gel packs may be added in kit packaging as protection against freezing or excessive heat damage.

Q: What are the appropriate shipping conditions for the cobas® liat Quality Control kits?

A: -20°C to ≤ 45°C (-4°F to 113°F), maximum 5 day transport time for the cobas Cdiff Control Kits

-20°C to ≤ 35°C (-4°F to 95°F), maximum 5 day transport time for all other cobas® liat Control Kits

Depending on the season and/or geographic location, ambient gel packs may be added in kit packaging as protection against freezing or excessive heat damage.

Q: What are the appropriate storage conditions for the cobas® liat Reagent kits?

A: All cobas® liat reagent kits should be stored at 2-8°C.

Q: What are the appropriate storage conditions for the cobas® liat Quality Control kits?

A: The cobas Cdiff Quality Control kits should be stored at 15-30°C.

All other cobas® liat Quality Control kits should be stored at 2-8°C.

Q: When do my reagent kits expire?

A: Assay tubes are stable until the date of expiration listed on the assay tube package. Do not use reagents beyond their expiration dates. Do not open individual tube packaging until you are ready to perform testing. Store the assay tubes at 2-8ºC. 

Q: When do my Quality Control kits expire?

A: The cobas® Cdiff positive and negative controls are stable at 15-30°C until the expiration date indicated on the control kit, regardless of the open date of the pouches.

The cobas® Strep A Quality Control Kit and cobas Influenza A/B & RSV Quality Control Kit positive and negative control tubes contained in factory-sealed pouches are stable at 2-8°C until the expiration date indicated on the control kit. After opening a pouch, these controls are stable for 90 days at 2-8°C or until the kit expiration date, whichever comes first. Write the date opened on the pouch where indicated. Close the zip lock seal on the pouch after each use.

For all other cobas® liat assays, the positive and negative controls are stable at 2-8°C until the expiration date indicated on the control kit, regardless of the open date of the pouches.

Q: How long can an assay tube sit at room temperature? 

A: Please refer to the relevant cobas® liat assay’s method sheet. All cobas® liat assay method sheets can be found under Guides and Documentation > Assay Method Sheets.

Q: How should I store my patient sample if it cannot be immediately tested?

A: Please refer to the transport and storage section of the relevant cobas® liat assay’s method sheet. All cobas® liat assay method sheets can be found under Guides and Documentation > Assay Method Sheets.

Q: Do we have to use the collection media indicated in the assay method sheets, or can we use another brand? 

A: To ensure test accuracy, use only the collection materials indicated in the relevant assay’s method sheet as they have been validated or approved for use with the cobas® liat system. All cobas® liat assay method sheets can be found under Guides and Documentation > Assay Method Sheets.

Q: Can I view the Ct values from my results?

A: Yes, the Ct values for positive sample results and positive control results are available in the ResultArchive.csv file. To access this file, archive results to a USB and then open the ResultArchive.csv file in Excel (or other spreadsheet application) to view these Ct values. For detailed instructions on this process, refer to the Quick Reference Guide Opening Result Archive Files with Microsoft Excel.

Additionally, Ct values for positive sample results and positive control results may be transmitted to connected hosts (DMS/LIS).

Q: Should I archive and delete data from my cobas® liat system?

A: Yes, we recommend periodically archiving and deleting results and audit trail data from the cobas® liat system to maintain optimal analyzer performance. Consider creating and retaining a problem report prior to exporting and deleting data from the analyzer, for any potential troubleshooting needs.

Q: What does Run status: Warning on my result report mean?

A: The Warning status is generated when the analyzer detects a potential issue, for example with motor movement, and assigns it a code with a low severity rating. A code with a low severity rating is treated as a warning and the instrument attempts a recovery. If the recovery attempt is successful, the script will proceed as intended and the run status Warning is generated on the result report. In this case, the analyzer is performing as intended and the results are valid.

If the recovery attempt is unsuccessful, the severity rating will be escalated, which signals the assay to abort. In this case the analyzer will not give a result and the run status will be Aborted.

Q: What is an assay abort?

A: An assay abort is the premature termination of a sample test. Assay aborts are designed to prevent excessive movements during operation that could result in analyzer damage. Occasional assay aborts are a normal and expected result of this important failsafe. Under normal operation, the analyzer alerts the user if a malfunction or error is detected. Please refer to the Troubleshooting section for information on how to troubleshoot aborts.

Q: What is an assay invalid? 

A: An invalid is generated when abnormalities in PCR amplification of the internal processing control or assay targets are detected. Invalid results can be expected to occur at a low rate when PCR conditions are not optimal. Please refer to the Troubleshooting section for information on how to troubleshoot invalids.