AYAhmed Yazıcı
← All projects

Case 08 / Healthcare + simulation

Orthopedic outpatient flow, modeled patient by patient.

A discrete-event simulation of the real outpatient workflow at Balta Limanı Kemik Hastanesi, developed using operational data collected at the hospital.

  1. 01 / ARRIVEAppointment or walk-inWalk-ins first pass through consultant registration
  2. 02 / EXAMFirst doctor visitPriority queue and doctor-specific service
  3. 03 / IMAGEX-ray if referredTwo rooms with their own queues
  4. 04 / FINISHFollow-up or departureReturn to the same doctor after imaging
Hospital resources
7 + 2doctors and X-ray rooms in the model
Patients generated
448in the documented seeded run
Patients completed
448all generated patients finished the workflow
01 / THE SYSTEM

One hospital day is many connected queues.

Patients do not all follow the same route. Some arrive for scheduled appointments, while walk-ins need consultant registration before joining the doctor workflow. Doctors may refer a patient for X-ray, after which the patient returns for a second examination.

The project represents those events and resource constraints as patient-level processes. It focuses on the hospital's orthopedic outpatient workflow captured by the collected data, rather than an abstract clinic example.

02 / MODEL DESIGN

Make the operating rules visible.

The configured model has seven doctors, two priority-based X-ray rooms, and one consultant. Appointment patients and walk-ins enter through different arrival processes. Each doctor has specific arrival, service, appointment, and imaging-referral distributions.

  • Appointment priority and a separate walk-in priority offset shape doctor queues.
  • Doctors pause for lunch from simulation minute 240 to 300.
  • Pre-lunch X-ray service time uses a 1.25× multiplier.
  • Walk-in generation stops at minute 420; scheduled appointment arrivals stop at minute 480.
  • The model keeps running after arrivals stop until active patients and queues clear.

Queue lengths are sampled every simulated minute. The output records patient completions, X-ray referrals, doctor examinations, consultant registrations, and queue histories.

03 / DEMONSTRATED RUN

A seeded run that drains the system.

The repository fixes its random seed at 42 for its documented default scenario. The figures below describe that single simulated run.

MeasureRecorded result
Scheduled appointments237
Appointment arrivals / walk-in arrivals235 / 213
Patients generated / completed448 / 448
X-ray patients341
Overall X-ray referral share76.12%
Consultant mean / maximum queue length2.76 / 10 patients
Simulation end time558 minutes

The simulation continued 78 minutes beyond the final appointment-arrival horizon to let the remaining patients finish. No patients remained at termination in this run.

04 / INTERPRETATION

What this evidence supports.

The model reproduces the configured patient routes and resource rules, and its documented run completes all generated patients. The output exposes where queues form and how much work reaches each resource.

Scope. The reported counts and referral share are sample outcomes from one seeded stochastic run. They are not estimates of long-run rates or evidence that a staffing change improves real-world patient care. Comparing policies would require repeated seeds and a defined evaluation design.