Improving waiting times and clinic flow in a tertiary diabetes centre

The Diabetes Centre (DBC) at Singapore General Hospital aims to provide patients with one-stop outpatient services. With increasing patient demand, new subspecialty services, high patient expectation, and ongoing research and teaching, the DBC’s daily operations were complicated and inefficient. This resulted in long in-clinic waiting times and low patient satisfaction. They decided they would need to streamline clinic flow and ensure that scheduling was planned according to patient demand.

Diagnosing system bottlenecks

To understand and analyse the bottlenecks within their system, a global assessment of all processes was performed over the course of one week. A spaghetti diagram highlighted congested areas within the clinic. A value stream map and time motion exercise tracked the amount of time patients were spending at various points in the clinic and their waiting times in between these points. To obtain baseline data and then monitor progress after implementing changes, the team chose three outcome measures to track:

  1. Patient turn-around time, or the amount of time a patient spent at the clinic from time of registration to time of payment.
  2. Waiting time to doctor consultation, which is the time difference between the patient’s appointment time and the actual time the patient ended up seeing the doctor.
  3. Patient satisfaction, or the number of compliments and complaints received on patient feedback forms.

The results of the time motion study revealed that the patient experience and overall time spent on each visit depended on many factors, including appointment scheduling, patient and doctor punctuality, wait times for test results, registration processes, medical record retrieval, and coordination between service providers. They chose three key areas that were crucial to improving efficiency and reducing the time each patient spent at the DBC:

  1. Decreasing waiting time to doctor consultation.
  2. Better communication and flow between staff.
  3. Reducing waiting time for payment and appointment rescheduling.


Here’s how they decided to tackle each of these areas:

1. Decreasing waiting time to doctor consultation.

A key problem that emerged was a mismatch between demand and the number of appointment slots available. Different doctors had varying workloads and overbooking was common. To address these issues, they began by identifying four doctors whose patients were waiting the longest to be seen. For these doctors, they matched supply to demand by turning unused new appointment slots into follow up slots, which were in higher demand. Then, using the results of the time motion study, they matched the length of the doctors’ appointment slots with the actual time each doctor was spending in consultation with patients. Finally, they changed the appointment times of each doctor to also align with the length of time doctors spent in consult with patients. After a three month pilot, these changes were made for all of the other remaining doctors.

To reduce the number of patients arriving late or not attending at all, they created an outpatient appointment reminder system by calling all new patients a week ahead of time to remind them of their appointments and tell them to arrive early for blood testing. They also prepared educational leaflets in four major languages with information about arriving early and how to prepare for certain blood tests.

2. Better communication and flow between staff.

The time motion study revealed that a lot of time was spent looking for and transporting patient case notes between different consult rooms. Front registration staff were recording many different appointment times on a small piece of paper, which led to confusion. They created a standard sheet to go with every set of patient notes, to allow for clear, standardised documentation, making it easier to locate patients.

3. Reducing waiting time for payment and appointment rescheduling.

Investigations revealed that there was often a long queue of patients waiting to pay and book their next appointment, especially in the late morning and close to lunch time. To combat this problem, a ‘floating’ staff member who did miscellaneous tasks was reassigned to be an extra cashier and registration staff were given alternating lunch breaks to ensure there were always enough cashiers available at the busiest times of day.


The primary goal of the improvement project was to reduce the length of time patients spent at the clinic from arrival and registration to payment and departure. There was no significant improvement in this particular measure, but the clinic did see positive changes in other areas:

- Thanks to the changes made to appointment scheduling, the percentage of patients seen by the doctor within 60 minutes of arrival increased from 80% to 84%.

- After implementing the appointment reminder system, the rate of new patients who did not attend decreased from 30.2% to 21.3%.

- The number of compliments received from patient satisfaction surveys increased from a baseline mean of 21.4 compliments per month to 27.1 compliments per month.

- Most significantly, by making changes to front desk staffing, patient waiting time to payment and appointment rescheduling decreased by 36.6%.

The team initially found it overwhelming to try and identify problems and decide how to address them. However, having a multidisciplinary team that included both clinical and administrative staff “allowed a true overview of all processes”. Feedback from patients was also instrumental in helping develop strategies.

“This high level of involvement from all staff with a strong patient-centred approach helped engage the buy in and cooperation that was necessary to make the project successful”.

The team also found it was very important to review baseline data in a structured and systematic way. Tracking several indicators while testing the changes allowed them to track and refine the most impactful changes and drop the ones that did not have the desired impact. You can read the full article about their work here.