Cytopathology and More | Automated screening workload limits are too high

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1. Cytotechnologists’ workday should not include more than seven hours of gynecologic (Pap test) screening in a 24-hour period, provided there are no additional duties or distractions.

Based on available evidence that fatigue and discomfort increase over time, No. 1 above is considered good practice. These recommendations apply only to gynecologic screening and do not necessarily apply to nongynecologic cytology, including immediate evaluation of adequacy of fine-needle aspirates. Non-screening time of gynecologic specimens must include at least two paid mini-breaks of 15 minutes each and a 30-minute lunch break in an eight-hour day. Breaks constitute a complete break from microscopy work and cannot include other activities such as data entry, quality assurance, and nongynecologic specimen immediate evaluation and screening. Time allotted for breaks is intended for mental and muscular rest, so it cannot be “worked through.” Employment for fewer than eight hours must also assume non-screening time of gynecologic specimens, including breaks, prorated to the total number of hours worked. For example, a person scheduled to screen Pap tests for a four-hour shift should have at least one 15-minute paid break and one 15-minute lunch break, which adds up to 3.5 hours of actual gynecologic screening and 30 minutes of non-screening.

3. Cytotechnologist average laboratory productivity should not exceed 70 slides per day using the Centers for Medicare and Medicaid Services recommendations for calculating workload (fields of view [FOV] only = 0.5 slide, full manual review [MR] = 1.0 slide, FOV + MR = 1.5 slide).

The current FDA workload limits for automated image-assisted screening methods, including the ThinPrep Imaging System and FocalPoint GS, are 100 slides per day, where slides are counted per the 2010 FDA bulletin. These rates are extremely high and may be associated with significant reduction in sensitivity. This American Society of Cytopathology recommendation is assuming a full manual review rate of imaged slides to be at least 15 to 20 percent (see recommendation No. 4). For example, with a 20 percent FMR, maximum number of slides examined per day will equal 80 “field of view only” slides (calculated as 80 × 0.5 = 40) plus 20 FOV + FMR slides (calculated as 20 × 1.5 = 30). So the total number of actual slides screened in this example is 100 slides (FOV and 20 percent FMR). We understand that screening rates vary from hour to hour, screener to screener, and slide to slide. This variation is expected as the complexity of the slides examined varies and performance of the cytotechnologist changes over time. These screening rates, therefore, are recommended as a maximum laboratory average, not as a maximum individual cytotechnologist performance.

4. The percentage of imaged slides that undergo full manual review should be at least either 15 percent, or twice (2×) the epithelial cell abnormality (ECA) rate, whichever is greater.

Studies have demonstrated that as workload and productivity increase, there is a tendency for FMR to decrease, which leads to decreased detection rates of abnormalities in the Pap test.

In summary, higher screening rates proportionally cancel out the increased sensitivity gained by imaging because there is a direct relationship between the amount of time spent screening slides and the accuracy of the reading. Increased cytotechnologist workload leads to reduced accuracy and higher false-negative rates. The current maximum FDA workload limits for automated image-assisted screening, including the ThinPrep Imaging System and FocalPoint GS (100 slides per day), are certainly too high for most cytotechnologists to achieve. Workload limits should not be based on extrapolated numbers and should take into account microscopic screening time, LIS time, and necessary breaks.

Cytotechnologists are not machines.

1. Renshaw AA, Elsheikh TM. Predicting screening sensitivity from workload in gynecologic cytology: a review. Diagn Cytopathol. 2011;39:832–836.
2. Elsheikh T, Kirkpatrick JL, Cooper MK, Johnson ML, Hawkins AP, Renshaw AA. Increasing cytotech workload above 100 slides per day using the ThinPrep imaging system leads to significant reductions in screening accuracy. Cancer Cytopathol. 2010;118:75-82.
3. Levi A, Schofield K, Elsheikh TM, Harigopal M, Chhieng D. Effects of increasing cytotechnologist workload using the location guided imaging system FocalPoint GS on SurePath Pap tests (abstract). Cancer Cytopathol. 2010;118(suppl 5):307.

Dr. Elsheikh is medical director of AP services, Cleveland Clinic Laboratories, Cleveland, Ohio.