Risk perception and disease knowledge in attendees of a community-based lung cancer screening programme

In England, a risk-based approach is used to determine eligibility for lung cancer screening. Ensuring effective communication and counselling of risk is therefore increasingly important. In this study, we explore the perception of lung cancer risk in attendees of a community-based screening service, located in socio-economically deprived areas of Manchester. We analyse responses based on demographic variables, calculated risk score and screening eligibility.

The Manchester Lung Health Check (LHC) programme invited ever smokers, age 55-80, to a lung cancer risk assessment in which their 6-year risk was calculated (using the PLCO_M2012 model). Those at high risk (PLCO_M2012 score ≥ 1.51%) were eligible for low dose CT (LDCT) screening. Prior to their assessment, attendees were invited to complete the study questionnaire, which assessed absolute and comparative risk perception, disease knowledge (incidence, survival, and risk factors), lung cancer specific worry, and mental health.

371 participants completed the questionnaire; 66% (n = 243) had linked clinical data. Perceived absolute risk was markedly higher than calculated risk (median: 20% vs. 1%; p < 0.001) and higher in women than men (25% vs. 15%; p = 0.001). There was no correlation between perceived absolute and calculated risk. Overall, 30% classified themselves at higher, and 21% at lower, lung cancer risk compared to others their age. Median PLCO_M2012 score increased with perceived comparative risk (p = 0.004). Those eligible for screening were more likely to: classify themselves at higher comparative risk (41% vs. 21%; p < 0.0001), report lung cancer-specific worry (27% vs. 10%; p = 0.001) and have indications of depression (20% vs. 10%; p = 0.05). Family history of lung cancer was significantly associated with higher comparative risk (_adjOR 4.03, 95%CI 1.74-9.3; p = 0.001).

Employing comparative rather than absolute risk may assist risk counselling. Further research is required to determine the optimal approach to risk communication in this setting.