A system dynamics simulation model of lung cancer screening uptake in Australia

Abstract

This research included two main components. The first involved the development of a qualitative causal loop diagram of lung cancer screening uptake using stakeholder input involving clinical and consumer experts and evidence from the existing literature. The causal loop diagram comprised three main perspectives of a lung cancer screening program: participant, primary care, and health system. Eight key drivers were identified within these perspectives that will likely influence screening uptake: (1) patient stigma; (2) patient fear of having lung cancer; (3) patient health literacy; (4) patient waiting time for a scan appointment; (5) general practitioner capacity; (6) general practitioner clarity on steps after an abnormal CT; (7) specialist capacity to accept referrals and undertake evaluation; and (8) health system capacity for scanning and reporting. Five key system leverage points to optimise screening uptake were also identified: (1) patient stigma influencing willingness to receive a scan; (2) general practitioner capacity for referral to scans; (3) general practitioner capacity to increase patients’ health literacy; (4) specialist capacity to connect patients with timely treatment; and (5) health system capacity to reduce scanning waiting times. The second component of this thesis involved the development of a quantitative system dynamics model to simulate the relationships identified in the causal loop diagram and to test four different scenarios. These included: (i) the implementation of a lung cancer screening program, (ii) the implementation of a lung cancer screening program combined with a screening awareness and stigma reduction intervention, (iii) the hypothetical scenario of 50% screening uptake, (iv) the hypothetical scenario of 100% screening uptake. Without a screening awareness and stigma reduction intervention, screening uptake is estimated to be around 5.6%. With a screening awareness and stigma reduction intervention screening the uptake is expected to double to 11%. A shift towards early-stage lung cancers was evident across all scenarios. Stage I cancers increased from 12% in the base case to 15.8% with a screening program to 18.4% with an additional screening awareness and stigma reduction intervention. The proportion of Stage IV cancers decreased from 64% in the base case to 53.9% with a screening program to 48.7% combined with a screening awareness and stigma reduction intervention an intervention.

Date of Thesis submission	2024
Original language	English
Awarding Institution	Western Sydney University
Sponsors	Australian Government Research Training Program Scholarship
Supervisor	Kate McBride (Supervisor), Andrew Page (Supervisor), Emily Stone (Supervisor) & Danielle Currie (Supervisor)