The glossary explains some of the words used across this website and covers some key cancer and research terms, which primarily focus on lung cancer.


Cancer treatment that uses the body’s immune system to fight cancer. It works by helping the immune system to recognise and attack cancer cells.1

Impact evaluation

An assessment of the possible intended and unintended consequences of an intervention. It compares these consequences against the outcomes that would have happened with no intervention.2

Implementation study

A type of study which seeks to investigate the practical requirements of implementing an intervention in the ‘real world’. Implementation studies may or may not be randomised. For lung cancer screening, this may include how to improve recruitment and participation rates, improve the efficiency of a programme or ensure the quality of screening between different sites. Often the terms ‘implementation trial’ (or study), ‘pilot’ and ‘feasibility study’ are used interchangeably. Although definitions vary, they often share common research objectives.3 See also ‘Feasibility study’, ‘Pilot’ and ‘Randomised controlled trial’


A rate-based measure used in epidemiology to understand the burden of a disease in a defined population and its change over time. It is expressed as the number of new cases of a disease per 100,000 people that are diagnosed within a specified time period.4 See also ‘Prevalence’

Incidental findings

Other diseases first discovered while an individual is undergoing a computed tomography (CT) scan for something else. For example, lung cancer may be detected through a routine chest CT, or a heart condition may be spotted during a lung cancer screening appointment.5 See also ‘Guidelines’ and ‘Incidental nodule management protocol’

Incidental nodule management protocol

A set of best-practice guidelines for how to clinically manage a person who had a computed tomography scan for a reason other than lung cancer screening, and was found to have nodules in the lung.5 This protocol standardises the steps needed to evaluate whether a person should be referred for further testing.6 See also ‘Guidelines’, ‘Incidental findings’ and ‘Nodule’


  1. Cancer Research UK. 2021. What is immunotherapy? Available from: [Accessed 10/08/2023]

  2. Stern E. 2015. Impact Evaluation: A Guide for Commisioners and Managers. London, England: Bond

  3. Abbott JH. 2014. The distinction between randomized clinical trials (RCTs) and preliminary feasibility and pilot studies: what they are and are not. Journal of Orthopaedic & Sports Physical Therapy 44(8): 555-58

  4. Global Lung Cancer Coalition. 2022. Glossary.  Available from: [Accessed 04/03/22]

  5. McNulty W, Baldwin D. 2019. Management of pulmonary nodules. BJR Open 1(1): 20180051

  6. Morgan M, Weerakkody, Y. 2022. Lung-RADS Reference article (, . [Updated 28/03/22].  Available from: [Accessed 11/04/22]