Can a checklist reduce SOS errors in chest radiography?

Rationale and Objectives. A previous study demonstrated unexpected protection from satisfaction of search (SOS) effects when observers verbalized the focus of their attention during visual search and interpretation of chest radiographs. We suggested that protection from SOS might have occurred if each observer developed an informal checklist to help generate the verbal descriptions. The objective of this study is to determine whether a formal checklist reduces SOS effects in chest radiology. Materials and Methods. Fifty-seven chest radiographs, half of which demonstrated diverse, native abnormalities were read twice by 20 observers, once with and once without the addition of a simulated pulmonary nodule. Area under the receiver operating characteristic (ROC) curve for detecting the native abnormalities was estimated for each observer in each treatment condition using the contaminated binormal ROC model. Radiologists in the current experiment used a checklist during the interpretation, rather than describing their visual search. Results were compared with those of the verbalization study, which used the same set of radiographs. Results. Although no SOS effect was found when the checklist was used, ROC performance was, on average, much poorer with the checklist than when ongoing search was reported verbally (0.68 versus 0.75, F(1,37) = 17.26, P < .001). Conclusions. Our results indicate that the recommendation to use a self-prompting checklist to counteract SOS is not warranted. The relative superiority of verbalizing search over using an imposed checklist may be based on the consistency of each of these interventions with the observer's internal strategy for searching radiographs.