GLI GLI Quality Tool
GLI Quality Tool — Version 2.0

Cycle time analysis for TB laboratory workflow improvement

In Australia, tuberculosis is uncommon compared with many other countries, yet laboratories from Sydney to Darwin still process specimens that require careful, timely handling. Public health laboratories in cities such as Melbourne and Perth support clinicians managing active cases, contact tracing in remote communities, and migration screening programs. With vast geography and relatively low case numbers, efficiency matters: each specimen often travels long distances and any delay can affect patient isolation decisions and community treatment programs. Workflow improvement planning is therefore a practical necessity, not just an administrative exercise.

Cycle time analysis is a straightforward but powerful technique borrowed from process improvement. It measures the elapsed time between defined points in a workflow, such as when a sputum sample arrives at the receiving bench and when a validated result is released to the clinician. By breaking the journey into discrete steps and timing each one, laboratory teams can see where value is added, where waiting occurs, and which activities could be reorganised. For TB laboratories, the approach works well because specimen pathways are well defined and regulatory expectations for turnaround time are clear.

The GLI Quality Tool provides a four-phase roadmap that supports laboratories in this kind of systematic improvement work. Each phase offers checklists, user instructions and downloadable templates aligned with twelve Quality Systems Essentials. Within that structure, cycle time analysis becomes a practical lens for assessing current performance, setting realistic targets, and tracking whether changes actually improve service delivery.

Mapping the TB laboratory workflow and capturing baseline data

Before any improvement can be designed, the team needs a clear picture of how specimens actually move through the laboratory. This starts with a process map, drawn by walking the specimen from the moment it arrives in the reception area through centrifugation, smear preparation, culture inoculation, identification, and finally reporting. In Australian laboratories, reception staff often juggle samples received by courier from regional hospitals, postal deliveries from remote clinics, and walk-in patients, so the first step is to capture all these entry points.

Once the map exists, baseline cycle times are collected over a representative period, usually two to four weeks, to capture typical variation. Stopwatches, spreadsheets, or barcode-based tracking systems can record the time each sample enters and leaves key workstations. Total cycle time is calculated from reception to result release, while step times highlight individual activities. Many teams find it useful to display this information on a simple value stream map so everyone can see where delays cluster.

This mapping exercise clarifies the role of each Quality Systems Essential in the workflow. Documentation records show when forms are completed and reviewed, equipment logs reveal whether instruments cause delays, and personnel rosters expose gaps in coverage. The Phase 1 resources of the GLI Quality Tool can be useful here, offering structured templates for capturing baseline information and aligning them with the twelve essentials.

Identifying bottlenecks and understanding variation

Bottlenecks rarely appear where the team expects them. A common finding in TB laboratories is that the smear microscopy station, often assumed to be fast, actually holds up processing because staining and reading protocols differ between shifts. Culture inoculation benches, by contrast, sometimes run smoothly because they are dedicated by protocol. Cycle time data quickly reveals these patterns and separates perception from reality.

Variation is just as important as averages. A median processing time of 24 hours may mask occasional samples that take four days because of equipment calibration, staff absences, or queueing during peak hours. Plotting cycle times on a run chart, or calculating standard deviations for each step, helps the team understand whether performance is predictable. In Australian laboratories serving large catchment areas, batch arrival patterns from regional flights can create spikes that need separate analysis.

Staffing patterns also affect variation. Turnover of experienced microscopists, in particular, can lengthen processing periods until new staff build proficiency. Laboratories planning improvements should consider a structured turnover analysis to anticipate and mitigate such disruptions. Understanding these human factors is essential because process redesign will fail if the team cannot operate it consistently.

Designing targeted improvements using quality systems essentials

With bottlenecks and variation identified, the improvement team can match interventions to the relevant Quality Systems Essential. If specimen reception queues are the problem, facility design and safety considerations might suggest redesigning the receiving bench. If smear staining takes too long, the answer may lie in equipment maintenance schedules, reagent preparation, or workload distribution between shifts.

Workload distribution is often a practical entry point because it requires relatively little capital investment. The usual approach involves balancing case numbers across early and late shifts, ensuring senior staff are available during high-volume periods, and clarifying handover responsibilities. A workload distribution framework offers a structured way to test different rosters and measure their effect on cycle times before committing to a permanent change.

Equipment-related improvements might include preventive maintenance calendars, parallel processing using multiple microscopes, or upgrading to automated staining systems. Documentation improvements usually involve standardising forms, introducing barcode labels, and digitising request forms where connectivity allows. Personnel improvements focus on competency assessments, continuing education, and supportive supervision, all of which reduce variation in processing times.

Piloting, measuring and adjusting the plan

Improvement plans work best when they are piloted on a small scale before full rollout. A pilot might run for one month in a single section of the laboratory, or focus on one specimen type such as sputum from respiratory clinics. During the pilot, cycle times continue to be measured, but the team also gathers qualitative feedback from staff about what works and what creates new frustrations.

Measurement during testing should be tight enough to detect meaningful change but not so burdensome that it disrupts the workflow being tested. Simple indicators, such as median total cycle time, percentage of results released within target time, and number of samples exceeding a threshold, are often sufficient. Australian laboratories accredited by NATA are familiar with this kind of indicator-based monitoring because it mirrors approaches used in broader quality management.

Adjustments are expected. A pilot in a Perth laboratory might reveal that a new shift pattern works well Monday to Thursday but creates handover problems before Monday. Evaluation rather than frustration should guide these changes. Testing on a small scale saves time and builds confidence before changes affect the wider service.

Sustaining gains through monitoring, training and continual improvement

Sustaining improvement requires ongoing attention to the system that supported the change. This means keeping visual management boards updated, reviewing cycle time data monthly, and incorporating the indicators into routine quality meetings. It also means revisiting the process map periodically because workflows evolve as equipment changes, staff rotate, and testing volumes shift.

Training is central to sustainability. New staff should be trained in the improved process, not the old one, and competency assessments should verify that they can perform each step within the expected cycle time. Experienced staff benefit from refresher sessions that reinforce standardisation and address drift, the slow return to old habits that commonly follows improvements.

Continual improvement, the twelfth Quality Systems Essential, ensures that progress does not stall. Teams can use short, focused improvement cycles to address remaining issues, such as reducing variation in culture reading times or streamlining result entry into laboratory information systems. By treating cycle time analysis as a recurring practice rather than a one-off project, laboratories build a culture where efficiency, quality and patient care reinforce each other.

The GLI Quality Tool offers a practical starting point for this work, with phase-specific checklists and downloadable materials that align with the twelve Quality Systems Essentials. Teams ready to begin can explore the Phase 1 resources to establish their baseline, then progress through the roadmap as their improvement plan matures. Whether your laboratory operates from a major metropolitan hospital or a regional centre, cycle time analysis offers a clear, measurable path toward better TB services for the communities you serve.