GLI GLI Quality Tool
GLI Quality Tool — Version 2.0

Creating a reliable TB laboratory inventory checklist

A tuberculosis laboratory depends on a steady supply of reagents, cartridges, stains, culture media, specimen containers, personal protective equipment, and other consumables. A missing item can delay testing, interrupt quality control, or force staff to use materials outside their validated conditions. An inventory checklist turns stock control into a routine, visible process rather than an emergency response.

The checklist should support the laboratory’s quality management system (QMS), fit the testing methods in use, and work in the local operating environment. A small microscopy service may need a simple paper stock card, while a culture or molecular testing facility may require batch tracking, temperature records, expiry alerts, and electronic reporting.

The GLI Quality Tool’s phased roadmap and twelve Quality Systems Essentials provide a useful structure for this work. Inventory control connects directly with equipment, purchasing and inventory, documents and records, process management, assessment, and continual improvement. The goal is a practical tool that helps staff know what is available, what is usable, what must be ordered, and what requires investigation.

Define the purpose and scope

Begin by stating what the checklist covers. Include all consumables and reagents required for specimen reception, preparation, testing, quality control, result reporting, cleaning, waste management, and equipment maintenance. Include items that are easy to overlook, such as printer labels, pipette tips, gloves, disinfectants, microscope immersion oil, control materials, and replacement filters.

Separate stock into logical categories. Reagents may include staining solutions, molecular assay reagents, extraction materials, culture supplements, and identification kits. Consumables may include tubes, slides, swabs, containers, cartridges, racks, and transport materials. Safety supplies should be visible as a separate category because shortages can immediately affect staff protection and laboratory operations.

The scope should also identify storage locations and responsible areas. A single checklist may cover the main store, refrigerator, freezer, testing benches, satellite rooms, and emergency reserve. Assigning ownership prevents the common problem of assuming that another section has checked or reordered an item.

Before finalizing the checklist, assess whether the laboratory is ready to implement the first phase of a structured quality program by using the phase-one readiness guide. This can help align inventory work with existing responsibilities, documents, and improvement priorities.

Choose the fields that staff must record

Each inventory line should identify one specific item and, where relevant, one specification. The name alone is rarely enough. Record the manufacturer, catalogue number, pack size, test platform, concentration, grade, and any compatible equipment. Different versions of a reagent may look similar but require different procedures or storage conditions.

Useful fields include the following:

Not every field must be completed in the same way for every item. A disposable tube may need quantity, lot, and expiry information, while a prepared reagent may also require preparation date, preparer initials, review date, and stability period after opening. The checklist should make these differences clear without becoming too complicated for routine use.

Use consistent units. Recording one item in boxes, another in individual pieces, and a third in millilitres makes stock calculations unreliable. Define whether the quantity means unopened packs, usable tests, individual units, or prepared volume. If a kit contains a fixed number of tests, record both the number of kits and the estimated tests remaining when this supports ordering decisions.

Build controls for receipt, storage, and use

Inventory management begins when supplies arrive. Staff should compare the delivery with the purchase order or packing list, inspect packaging, verify the lot and expiry date, and record any temperature excursion or visible damage. Reagents requiring cold storage should move promptly to the correct location, with the receiving action documented.

A checklist should support first-expiry, first-out use rather than relying only on the date of arrival. Staff should place items with the earliest expiry where they will be selected first, while keeping lot separation clear. Do not use expired, contaminated, leaking, discoloured, or improperly stored materials unless an authorized procedure specifically permits evaluation and release.

Storage controls should reflect the manufacturer’s instructions and the laboratory’s risk assessment. Shelves and refrigerators need clear labels. Reagents should not be stored with food, personal items, or incompatible chemicals. Flammable materials, corrosives, infectious materials, and cleaning agents may require separate arrangements. Temperature-sensitive stock needs documented monitoring, defined acceptable ranges, and an action plan for excursions.

The checklist should also capture opening and preparation. A reagent can remain within its printed expiry date but become unsuitable after opening, thawing, reconstitution, or repeated temperature changes. A simple “opened on” field, combined with a discard date calculated from the standard operating procedure, can prevent inappropriate use.

Set stock levels and review frequency

Minimum and maximum levels should be based on actual consumption, supplier lead time, storage capacity, and the consequences of a stockout. A busy molecular testing section may need a larger safety stock than a low-volume microscopy service, while an item with a short shelf life should not be over-ordered. Review these levels after changes in testing volume, instrument use, procurement delays, or disease response requirements.

A practical reorder point can be estimated from average use during the supplier lead time plus a safety reserve. For example, if a laboratory uses 20 cartridge boxes per month and delivery commonly takes six weeks, the reorder point should cover expected consumption during that period and include additional stock for delays. The exact calculation may be simple, but it should be documented and reviewed rather than based on memory.

Different items need different review frequencies. High-use or high-risk materials may be checked daily or weekly. Stable, low-use supplies may be reviewed monthly. Emergency items such as respiratory protection, spill materials, and critical controls deserve a defined minimum quantity even if they are rarely used.

Checklist area Routine record Trigger for action Responsible role
Receipt Quantity, lot, expiry, condition Mismatch, damage, or temperature concern Storekeeper or designee
Storage Location and temperature Excursion or misplaced stock Section supervisor
Daily use Quantity issued and remaining Level reaches reorder point Testing staff
Reagent preparation Date, preparer, expiry after opening Unlabeled or overdue material Bench supervisor
Monthly review Physical count and record comparison Variance, excess, or approaching expiry Inventory lead
Disposal Item, reason, quantity, authorization Expired, contaminated, or rejected stock Quality or safety officer

Reconcile records with physical stock

A checklist is effective only when written records match what is actually on the shelf. Schedule physical counts and compare the result with stock cards, spreadsheets, or laboratory information systems. Investigate differences rather than silently correcting them. Variances may indicate recording errors, unreported transfers, damaged stock, theft, incorrect units, or materials used for training and verification.

Use a simple variance record that states the item, expected quantity, counted quantity, difference, likely cause, corrective action, and reviewer. Repeated discrepancies may show that the process is too difficult, that staff lack time, or that stock is being stored in several uncontrolled locations.

Electronic tools can improve visibility, especially when they provide expiry reminders and consumption trends. However, digital records do not replace defined procedures or staff accountability. When moving from paper records, the laboratory should plan data fields, user access, backup, validation, and migration of active stock. Guidance on moving to electronic TB records can help connect inventory records with broader laboratory information practices.

Keep the checklist itself under document control. Give it a title, version number, approval date, review date, and document owner. If a spreadsheet is used, protect formulas, restrict editing of approved fields, and retain a backup. If paper forms are used, provide a clear filing location and define how completed pages are reviewed and archived.

Use the checklist to manage risk and quality

Inventory data should inform more than purchasing. Trends can reveal excessive wastage, repeated stockouts, poor forecasting, inefficient pack sizes, or problems with a supplier. Track near-expiry items early enough to redistribute them safely within the laboratory or to another authorized facility, subject to applicable procedures and transport conditions.

Link stock records to quality events. An unexpected control failure may be associated with a degraded reagent, incorrect storage, or a lot change. When a problem occurs, the inventory checklist can help identify affected batches, testing dates, and specimens that may require review. Lot verification and acceptance testing should be documented before a new reagent or kit enters routine use.

Recommendations for maintaining a usable system include:

Training should use real examples from the laboratory. Staff need to practice receiving a delivery, recording a lot number, calculating usable stock, responding to a temperature excursion, and quarantining an unsuitable item. Competency checks can then confirm that the checklist is understood and used consistently.

Review performance and keep the process current

The inventory process should have measurable indicators. Useful measures include the number of stockout days, percentage of critical items within target levels, expired stock value, unresolved physical-count variances, and the proportion of deliveries checked on receipt. Choose a small set that staff can maintain accurately and review them at regular quality meetings.

When an indicator worsens, look for the process cause. A stockout may result from delayed procurement, inaccurate consumption records, an unrealistic reorder point, or an approval bottleneck. Corrective action should identify who will act, what will change, and when effectiveness will be checked.

Review the checklist whenever a test method, supplier, storage area, instrument, or procurement arrangement changes. At least annually, confirm that item specifications, minimum levels, storage requirements, and responsible roles remain accurate. Remove obsolete fields and add new controls when experience shows that an important risk is not being captured.

A well-designed inventory checklist gives TB laboratory staff a shared view of readiness. It protects the integrity of reagents, supports safe work, reduces avoidable waste, and provides evidence that supplies are controlled throughout their life cycle. Adapt the fields to local capacity, approve the procedure through the QMS, train the people who will use it, and begin with a focused review of critical items before expanding to the full inventory.