Overview of the interactive map interface

There are two types of map that you can use to explore data on low-dose computed tomography (LDCT) lung cancer screening:

  • a pin map provides an overview of individual clinical trials, implementation studies and national or regional LDCT screening programmes contained in the data set
  • a heat map displays the policy context for LDCT screening of lung cancer in each country. The policy context map can be filtered by lung cancer cases and deaths per 100,000 population (incidence and mortality).

You can toggle between the two maps by clicking the respective map buttons in the navigation bar. Data tables provide additional information on what is known about an individual study/programme or a country’s position on the LDCT lung cancer screening implementation pathway.

For more information, including the search strategy, click the button below to read the interactive map methodology.

Interactive map of lung cancer screening: methodology

Key features of the map interface

You can explore the interactive map in a variety of ways, depending on what type of information you are most interested in. For both maps, you can:

  • Browse by location: click on the ‘quick start’ function to Zoom in to different areas of the map at the country and city level. You can reset the search by clicking ‘back to quick start’ at the top of the country list.
  • Explore individual entries or countries: click the pins or the outline of a country on the heat map to view more information.
  • Refine your search: Filters in the navigation bar can be opened to reduce the number of pins or countries that appear on the map. On the heat map, countries can be filtered based on country status; on the pin map, filters include (but are not limited to) entry type, features of the study/programme and availability of results.
  • Search for something specific: begin typing into the search bar and it will update and filter results for you in real time.

Interacting with either the pin map or the heat map will trigger data to appear in a ‘data dashboard’. The dashboard sits to the left of the map when using a desktop computer (recommended), or replaces the map view when using a mobile device.

The data dashboards display the following:

  • Pin map dashboard: around 20 core variables from the full data set for each individual map entry. This dashboard contains key information such as research objectives, the eligible population and, if reported, the participant outcomes from screening for the study/programme.
  • Heat map dashboard: overview information about each country, such as whether there is a national cancer control plan, and a rough indication of how close that country is to implementation of LDCT screening for lung cancer.

Sharing the data:

You can easily share a direct link to an entry on the pin map or heat map using the ‘Share link to entry’ button or ‘Tweet this entry’ button.

Definitions applied to the interactive map interface

The full data set contains more than 50 variables. All of the definitions for the variables used to build the interactive map are included in the full methodology and the cover sheet for the CSV database download.

Click here to download the full data set.

Outlined below are explanations for a small number of these variables, which we hope will support you in engaging with the data set.

Throughout the interactive map, missing data are indicated by a dash (‘–’) and if a variable does not apply this is indicated by ‘N/A’.

For other definitions around lung cancer screening, please click the button below to visit the glossary.

Glossary

Pin map

Acronym Acronym used to abbreviate the full name of the study/programme for this map – including official acronyms. If an official acronym cannot be identified, one will be drafted to optimise the user experience of the map interface.
Design Whether the entry is a clinical trial, implementation study or national/regional programme (see glossary)
Status Whether the study/programme is ongoing (active) or complete (inactive)
Centres in country If the study/programme is an international multicentre initiative, the number of centres/sites within this country
Screening interval The frequency of screening offered to participants at baseline or prior to enrolment (e.g. annual scan)
Radiation dose reported Whether information on the level of radiation emitted by a single LDCT scan is available in the literature (yes, no)
# Participants targeted The number of participants that the study/programme seeks to enrol or the total number of participants that have undergone LDCT screening so far
# participants screened to date The total number of participants last reported to have undergone LDCT screening so far
Research focus e.g. Workforce capacity, Barriers to screening, Cost-effectiveness, Eligibility criteria
Age (years)a The minimum and maximum age considered eligible for screening (e.g. 50–75)
Smoking history: PYsa The minimum number of pack-years’ (PYs) smoking history a person is required to have to participate in screening, e.g. ≥30
Smoking history: YSQa The minimum number of years since quitting smoking (YSQ) required for a person to participate in screening e.g. ≤15
Never smokers Whether people who have never smoked are eligible to participate in screening
Other criteria The number of other risk factors considered when assessing whether a person is eligible for screening, such as exposure to asbestos or family history of lung cancer (e.g. 2)
Screening uptake (%)b Proportion of target population that responded to an invitation for screening and attended for an LDCT baseline scan
Confirmed lung cancer cases (%)b Proportion of participants who underwent baseline LDCT screening and were reported to have a true positive (confirmed) result for lung cancer
Stage I/II lung cancer cases (%)b Overall proportion of participants in which lung cancer was detected and diagnosed at stage I/II

a For age and smoking history, if there is any variation based on other risk factors for lung cancer, this will be indicated by an asterisk and footnote..

b Proportions expressed as percentages (%)

Heat-map

Lung cancer incidence The number of lung cancer cases per 100,000 population from the GLOBOCAN 2020 data set (world age-standardised rate, including sex-specific rates)1
Lung cancer mortality The number of lung cancer deaths per 100,000 population from the GLOBOCAN 2020 data set (world age-standardised rate, including sex-specific rates)1
National cancer control plan (NCCP) Whether there is an NCCP available, and if so, the year the last NCCP was published and whether it discussed a strategy for the early detection of lung cancer
Population-based cancer registry (PBCR) Whether there is a population-based cancer registry that captures cancer incidence/mortality in a given country
Country status Only the latest ‘stage’ that a country is along the lung cancer screening implementation pathway will be shown.

Unknown status: Either no data could be identified from the literature search, or there are clinical trials or studies related to LDCT lung cancer screening, but no formal position on lung cancer screening at the national level is known

Implementation research: The country has previously or is currently conducting small-scale, regional or national implementation studies, including pilot programmes

Formal commitment to implement: The country has formally committed to the implementation of LDCT lung cancer screening in its National cancer control plan, or other official legislation/notices  

Implementation roll-out: An organised LDCT screening programme is being rolled out or has previously been rolled out to the entire eligible population within a certain region of the country, or nationwide.

References

  1. Ferlay J, Ervik M, Lam F, et al. 2020. Global Cancer Observatory: cancer today. [Updated 01/12/20]. Available from: https://gco.iarc.fr/today [Accessed 25/02/22]