Breast screening technologists: when is a difficult case truly difficult and for whom?

Each year almost all film readers in the UK Breast Screening Programme voluntarily read a set of difficult mammographic cases as a means of self-assessing their film reading skills. We set out to investigate what case characteristics, if any, actually constituted a ‘difficult’ or ‘easy’ case in the opinion of radiological experts. We also examined how UK Breast Screening personnel performed on those cases which the experts deemed were difficult, in order to build up a profile of the types of cases that provide film readers with the most problems. We examined two main elements of case diagnosis, case classification and case features and investigated if there were any group differences in terms of case difficulty and the percentage of incorrectly reported cases. Data from over 15 radiological experts and approximately 400 film readers were compared on 180 cases. Significant differences were found between the expert and screening populations (p < .05) in terms of these case characteristics. These data contribute to the understanding of just what constitutes a difficult case as considered by experts and other film-readers, with a view to elucidating the type of cases most appropriate for advanced mammographic training.