Temporal characteristics of laboratory screening errors in cervical cytology.
OBJECTIVE
To explore the temporal characteristics of laboratory false negative reports in cervical cytology.


METHODS
The temporal characteristics of 198 false negative cervical cytology cases were compared with those of 750,805 control cases.


RESULTS
The false negative rate did not vary significantly by month, day of the week or time of day. The false negative rate was lowest for slides that took between 4 and 5 minutes to screen and increased significantly with screening times that were longer than 5 minutes. The false negative rate did not vary by the number of cases already authorized in a given day. After 40 cases had been authorized in a given day, the false negative rate fell for subsequent cases, but this did not reach statistical significance. The false negative rate was higher during periods when prescreening was performed.


CONCLUSIONS
Further studies of the relationship between time and false negative reports are needed. These would provide an evidence base to help promote safe working practices within laboratories and a more objective setting of maximum daily productivity levels for cytotechnologists.
Mitchell
Heather
H
Victorian Cytology Service, Carlton South, Australia. h.mitchell@bigpond.com
Hocking
Jane
J
Saville
Marion
M
D002277:Carcinoma / Q000175:diagnosis*; D002584:Cervix Uteri / Q000473:pathology*; D003951:Diagnostic Errors / Q000517:prevention & control / Q000706:statistics & numerical data*; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D008403:Mass Screening / Q000592:standards / Q000706:statistics & numerical data; D015588:Observer Variation; D013997:Time Factors; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis*; D014626:Vaginal Smears / Q000592:standards / Q000706:statistics & numerical data*; D016526:Workload / Q000592:standards / Q000706:statistics & numerical data