There are deep problems related to international comparisons of crime, according to Professor Marcelo Aebi of the University of Lausanne.
He told the Association for Criminal Justice Research and Development annual conference on 5 October 2018 that statistics are influenced by the moment of their collection.
In general, countries recording crime data when it is reported to the police (input statistics) usually have higher rates of crime than those recording it when the police finish the investigation (output statistics).
Professor Aebi pointed out that online offences are almost absent from police statistics. He recommended flagging the cases that have a cyber-component to allow estimates of the percentage of offences that are tech-related.