In the realm of occupational health, employers expect timely, accurate and confidential fitness-for-work decisions. Candidates expect a coordinated experience rather than repeated requests for information, avoidable appointment delays or uncertainty about when their certificate will be available.
When results accumulate in queues, the underlying issue is rarely a single individual’s performance. More often, the end-to-end value stream contains excessive waiting, incomplete inputs, disconnected systems, batch processing and unclear hand-offs.
Value Stream Mapping (VSM) provides a disciplined way to see the entire pathway. Instead of optimising only booking, nursing, pathology or physician review, the team studies how information and clinical work flow from employer referral to certificate issue and employer notification.
The method aligns naturally with the Define phase of Lean Six Sigma, the Measure phase and DMAIC improvement. It also provides the evidence needed to distinguish genuine capacity constraints from delays created by process design.
Important: The figures in this guide are a realistic worked example for improvement planning. They are not clinical benchmarks. Each clinic should validate its own data, privacy controls, medical governance requirements and regulatory obligations.
1. What Value Stream Mapping Reveals in Occupational Health
A value stream includes every activity required to deliver a service, together with the movement of information, records, samples and decisions.
For a pre-employment medical, value-adding work may include:
- Performing clinically required examinations.
- Conducting audiometry and spirometry.
- Collecting pathology samples.
- Reviewing results and making a fitness-for-work decision.
- Issuing the certificate required by the employer.
Other activities may be necessary but non-value-adding from the candidate’s perspective, such as waiting for a booking, chasing missing questionnaire fields, moving files between systems or waiting for physician review.
The fundamental purpose of VSM is to compare:
- Value-added time: Hands-on work that changes the service or produces a required clinical outcome.
- Non-value-added time: Waiting, queues, rework, duplication, unnecessary movement and avoidable administration.
- Total lead time: Elapsed time from referral receipt to certificate notification.
- Process Cycle Efficiency (PCE): Value-added time divided by total lead time.
The Lean 6 Sigma Hub Process Cycle Efficiency Calculator can help teams quantify how much of the total pathway creates customer value.
A high-quality map is based on direct observation. The NHS Value Stream Mapping guidance similarly recommends walking the pathway, recording actual cycle times, queues, defects and information flows rather than relying only on documented procedures.
2. Select the Scope: One Complete Candidate Journey
A useful scope begins with a clear start and finish.
Start point
Employer booking or candidate referral received and accepted by the clinic.
End point
Fitness-for-work certificate issued and notification securely sent to the employer or authorised recipient.
The in-scope pathway should include:
- Employer booking and candidate referral.
- Referral validation and registration.
- Pre-medical questionnaire sent, completed and reviewed.
- Appointment scheduling and confirmation.
- Clinical examination.
- Audiometry.
- Spirometry.
- Pathology collection.
- Pathology result receipt and reconciliation.
- Physician review.
- Certificate preparation and issue.
- Employer notification and case closure.
Keep the map at approximately 8–10 major process boxes. A process map can describe every task. A VSM should instead expose the flow, the queues and the major constraints.
Include the people who operate the process: booking staff, nurses, technicians, pathology liaison staff, physicians, administration and employer account representatives. Their observations will often reveal the difference between the official workflow and the real one.
3. Current-State Map: The Referral-to-Certificate Baseline
Consider a clinic receiving 420 referrals per week, equivalent to approximately 84 referrals per working day.
The current-state pathway is:
Employer referral → Booking queue → Questionnaire → Clinic appointment → Audiometry and spirometry → Pathology → Results compilation → Physician review → Certificate issue → Employer notification
The clinic’s observed baseline is:
| Process measure | Current-state result |
|---|---|
| Referrals per week | 420 |
| Average referral-to-certificate service time | 8.5 business days |
| End-to-end lead time used for PCE analysis | 11.4 days |
| Value-added clinical time | 52 minutes |
| Appointment duration | 75 minutes |
| Average booking lead time | 2.6 business days |
| No-show rate | 9% |
| Incomplete questionnaires requiring follow-up | 14% of files |
| Pathology turnaround | 1.8 days average |
| Physician review capacity | 2 physicians × 30 files per day = 60 files/day |
| Certificates issued | Approximately 60 per day |
| First-pass yield | 86% |
| Physician review queue | 120 files at week-end |
The numbers reveal a structural imbalance. Average demand is 84 referrals per day, while physician review capacity is 60 files per day. Unless work is redistributed, demand will create a review queue of approximately 24 files per day, before accounting for incomplete questionnaires, no-shows, repeat tests or complex cases.
Worked PCE calculation
Using the defined baseline:
- Value-added clinical time = 52 minutes
- Total lead time = 11.4 days
- Total elapsed time = 11.4 × 24 × 60 = 16,416 minutes
Therefore:
PCE = 52 ÷ 16,416 × 100 = 0.32%
This does not mean the clinic is only 0.32% productive. It means that only 0.32% of the candidate’s elapsed journey is hands-on value-added time. The remaining time is dominated by waiting, scheduling, information gaps, result batching and review queues.
The 14% rework rate also has a direct impact. At 420 referrals per week, approximately 59 files require additional information. If each follow-up consumes 12 minutes of administrator time, the clinic spends nearly 12 hours per week on avoidable rework before considering the delay experienced by the candidate or employer.
4. The Eight Wastes in an Occupational Health Clinic
Use the DOWNTIME acronym to classify waste without assigning blame.
D, Defects
Incomplete questionnaires, incorrect employer requirements, missing signatures, invalid samples, unreadable test outputs or certificates requiring correction.
O, Overproduction
Preparing physician review packs before all required results are available, or generating duplicate certificates and reports for multiple recipients.
W, Waiting
Candidates waiting for appointments, files waiting for pathology, pathology waiting for collection batches and completed assessments waiting for physician review.
N: Non-utilised talent
Booking staff repeatedly chasing information instead of improving referral quality, or clinicians spending time on preventable administrative corrections.
T, Transportation
Moving paper files, printed results or physical samples between rooms and departments when secure digital transfer could be used.
I, Inventory
Work in process such as unbooked referrals, incomplete questionnaires, unreviewed files and certificates awaiting dispatch.
M, Motion
Repeatedly searching across systems, walking to retrieve equipment, locating paper forms or switching between disconnected screens.
E: Extra-processing
Re-entering candidate information, duplicating clinical observations, manually reconciling pathology results or requiring multiple approval signatures for a standard case.
The Analyse phase should then separate symptoms from root causes. Useful tools include a Pareto chart of rework reasons, a process capability review of lead time, a cause-and-effect diagram and a stratification of cases by employer, test bundle and complexity.
5. Future-State Design: Build Pull and Standard Work
The future state should not simply ask staff to work faster. It should redesign the flow so complete work reaches the next step at the right time.
Pre-appointment digital questionnaire
Use mandatory fields, employer-specific requirements and automated validation before the appointment is confirmed. Route incomplete questionnaires back to the candidate or employer with a clear exception message.
Target outcome: reduce incomplete files from 14% to 4% and raise first-pass yield from 86% to 96%.
Standardised clinical bundle
Create standard work for the examination, audiometry, spirometry and pathology sequence. Define the order of activities, equipment checks, documentation requirements and escalation rules.
This reduces variation in appointment duration and prevents missing-test rework.
Pathology fast lane
For standard pre-employment panels, establish a dedicated collection and transport pathway with defined cut-off times, specimen tracking and result integration. Complex or specialised tests should remain in a separate exception pathway.
Target outcome: reduce average pathology turnaround from 1.8 days to 0.75 days.
Physician review pull
Physicians should pull completed files based on readiness rather than receiving large batches. Use protected review slots aligned to the completion rate of clinical assessments and pathology.
With demand exceeding current capacity, the clinic should also review case segmentation, physician session design, delegation of appropriate administrative checks and escalation rules for non-standard cases. Clinical decisions must remain with appropriately authorised professionals.
Single electronic certificate pathway
Use one controlled workflow for certificate preparation, review, issue and secure notification. The system should show status, owner, due date and missing information without requiring duplicate tracking spreadsheets.
6. Current State Versus Future State
| Key metric | Current state | 90-day future-state target |
|---|---|---|
| Referral-to-certificate lead time | 8.5 business days | 3.5 business days |
| PCE analysis lead time | 11.4 days | 4.5 days |
| Value-added process time | 52 minutes | 48 minutes through standard work |
| Process Cycle Efficiency | 0.32% | 0.74% |
| Rework rate | 14% | 4% |
| No-show rate | 9% | 5% |
| Physician review backlog | 120 files | Below 20 files |
| On-time certificate rate | 68% | 95% |
| Cost per medical | $186 | $160 |
The future-state process may contain approximately the same amount of clinical work. The improvement comes from removing the time between activities, improving input quality and matching review capacity to demand.
7. A 90-Day Kaizen Sequence
Wave 1: Days 1–30, Stabilise and measure
Owners: Clinic manager, booking lead, Lean Six Sigma project lead and physician champion.
Actions:
- Confirm operational definitions for lead time, rework, no-show, first-pass yield and on-time issue.
- Capture 30 days of baseline data.
- Introduce a daily visual management board.
- Categorise missing questionnaire information.
- Separate standard cases from complex cases.
- Confirm the real physician review capacity and demand profile.
Expected impact: Reduce hidden variation, establish reliable data and prevent the queue from growing unnoticed.
Wave 2: Days 31–60, Improve the front end and clinical flow
Owners: Digital workflow owner, nursing lead, pathology liaison and booking team.
Actions:
- Pilot the digital questionnaire with the highest-volume employer group.
- Introduce automated appointment reminders and confirmation links.
- Publish standard work for the clinical bundle.
- Launch the pathology fast lane for standard panels.
- Add an exception queue for incomplete or non-standard files.
Expected impact: Reduce rework to 8% or below, lower no-shows to 6% and shorten pathology turnaround to approximately 1 day.
Wave 3: Days 61–90, Establish pull and control
Owners: Medical director, physician lead, clinic manager and quality lead.
Actions:
- Implement physician review pull based on file readiness.
- Create protected daily review capacity.
- Introduce the single electronic certificate pathway.
- Review daily demand against review capacity.
- Display lead time, backlog, first-pass yield and on-time issue rate.
- Audit the process weekly and update standard work when conditions change.
Expected impact: Reduce the review backlog below 20 files, achieve 95% on-time certificate issue and reach a referral-to-certificate lead time of approximately 3.5 business days.
Turn Occupational Health Flow Into Measurable Improvement
Value Stream Mapping gives occupational health leaders a shared operational language. It connects candidate experience, employer service levels, clinical governance, capacity planning and Lean Six Sigma metrics in one view.
The most important lesson is clear: the backlog is usually created between process steps, not during the clinical work itself. By improving referral quality, standardising the assessment bundle, accelerating pathology, creating physician review pull and controlling the certificate pathway, clinics can improve speed without compromising clinical quality or confidentiality.
If you want to lead this type of improvement with confidence, Lean 6 Sigma Hub’s CSSC-accredited Green Belt training covers process mapping, data collection, root-cause analysis, hypothesis testing, piloting, control plans and sustainable change through self-paced online learning.
Enrol in Lean Six Sigma certification today and build the capability to improve occupational health pathways with evidence, structure and measurable results.
Kaizen. Kai-Care. Kai-Done. Lean Six Sigma
