Extracting and tidying up data from graphs in the National Ambulance Syndromic Surveillance System (England)

I extracted Cardiac/Respiratory Arrest data from graphs in five publications from the UK Health Security Agency/Public Health England bulletins on the NASSS. The five publications were:

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/860059/NASS_Bulletin_2020_03.pdf

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/871917/NASS_Bulletin_2020_10.pdf

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/954014/NASS_Bulletin_2021_02.pdf

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/966198/NASS_Bulletin_2021_08.pdf

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1050383/UKHSA_NASS_Bulletin_2022_03.pdf

The copied graphs were uploaded into WebPlotDigitizer (https://automeris.io/WebPlotDigitizer/) after some mild modification with GIMP (https://www.gimp.org) to remove gridlines and the daily data trace.

This graph shows all the data from the four reports plotted together.

This graph shows which data from each report was used. It also shows interpolated points (in grey) used to fill the gaps between datapoints read using WebPlotDigitizer.

Data was saved as .csv files then tidied in R (https://cran.r-project.org/) to remove duplicates and combine the datasets. Simple graphs were made using ggplot2 (https://ggplot2.tidyverse.org).

The data and reports shared here are available under the Open Government Licence (https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/)

The graph style with lines showing where each year starts and ends, and labels for each year, was developed using example code from http://www.jasonfabris.com/blog/dteformat/