Guidance

Guide to contributory factors (and road safety factors) for reported road casualty statistics

A guide to use of the contributory factors data which form part of the Department for Transport's reported road casualty statistics, and the new road safety factors which will in time replace them.

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Details

Contributory factors apply to collisions recorded under the pre‑2024 STATS19 specification. Road Safety Factors (RSFs) are collected under the 2024 specification. Users should exercise caution when comparing results across specifications.

This guideguidance provides aan brief overview of the contributory factors data(CFs) and road safety factors (RSFs) recorded as part of the STATS19 road collision data collection,collection. includingIt thingsexplains tohow bethese awaredata ofare whencollected interpretingand thepublished, datahow tables,the andtransition informationfrom relatingCFs to RSFs affects the completenessinterpretation of the data.statistics, and factors users should consider when carrying out analysis.

TheRoad guidesafety focusesfactors onare replacing contributory factors,factors whichfollowing torecommendations from the end2018 ofSTATS19 2023review. makeAs uppolice mostforces ofhave adopted the new STATS19 specification at different times, recent statistics contain a mixture of collisions recorded data,using butboth alsosystems. referencesInitial theanalysis newsuggests roadthat safetythis transition has affected the factors whichrecorded willby police officers, meaning that direct comparisons between CF-based and RSF-based data should be collectedmade inwith future.caution.

TheThis guide covers:

  • an overview of contributory (andfactors and road safety)safety factors
  • strengths and weaknesseslimitations of the data
  • datathe confidentialitytransition from contributory factors to road safety factors, including implications for analysis and accessinterpretation
  • furtherdata informationconfidentiality, includingaccess linksarrangements toand datapublished collection formsoutputs
  • analysiscoverage ofand contributorycompleteness of factor reporting
  • analysis of reporting patterns by police force, road type and road user type
  • future developments and planned improvements to the statistics

Further information onrelating anyto aspect of contributory factors or road safety factors data can be addressedobtained tofrom the road safety statistics team viausing the contact details below.

Contact us

Road safety statistics

Updates to this page

Published 29 September 2022
Last updated 2530 SeptemberJuly 20252026 href="#full-history">+β€” show Show all updates
  1. Updated with 2025 data

  2. Updated with details of road safety factors based on 2024 data.

  3. Updated with 2023 data

  4. 2022 reported road casualties Great Britain report published.

  5. First published.

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