Comparative yield of endocervical and metaplastic cells. Two sampling techniques: wooden spatula and cytology brush.

OBJECTIVE

To compare two sampling techniques in their ability to obtain endocervical and metaplastic cells from the Papanicolaou smear.

DESIGN

Prospective clinical trial comparing the criterion standard of a wooden spatula to a cytology brush.

SETTING

Community-based family medicine clinic in London, Ont.

PATIENTS

Consecutive sample of 102 women aged 15 to 58 years requiring a Pap smear between October 1992 and October 1993 who presented to the office of their family physician and were assessed by one resident or one faculty physician.

INTERVENTIONS

A Pap smear was obtained from each participant using first the wooden spatula and then the cytology brush.

MAIN OUTCOME MEASURES

The number of Pap smears done in the study population that contained endocervical or metaplastic cells.

RESULTS

Endocervical cell yield was significantly greater using the cytology brush (93.1%) than using the spatula (61.8%) (P < 0.001). There was no significant difference in metaplastic cell yield between the cytology brush (71.6%) and the spatula (63.7%). At least one of these cell types was identified on 95.1% of cytology brush samples and on 79.4% of spatula samples (P < 0.001). The resident and faculty physician were not significantly different in their rate of detecting endocervical or metaplastic cells.

CONCLUSIONS

Adding a cytology brush sample to the Pap smear resulted in a significant increase in the rate of Pap smears that detected cells. The cytology brush was significantly better than the spatula for detecting endocervical cells (P < 0.001), but not significantly better for detecting metaplastic cells.