Background
To obtain an adequate cervical (Papanicolaou) smear, the squamous-columnar junction should be sampled as carcinoma develops preferentially in this transformation zone. The purpose of this study was to compare the adequacy of cervical smears taken with the Ayre spatula as opposed to the cytobrush.

Methods
This was a retrospective analytical study. One sampler, an experienced general practitioner, took the smears in the period 1990 to 2004. Initially, the Ayre spatula was used to consecutively sample the cervix and thereafter, a cytobrush alone was used. Two groups were thus formed for comparison. The presence of endocervical cells was accepted as an indicator of an adequate smear.

Results
A total of 4561 smears were taken and 247 had no endocervical cells. Of 2006 smears taken with a cytobrush, 1955 (97.5%) contained endocervical cells compared with 2325 (91%) of 2555 smears taken with an Ayre spatula. The difference was significant with an Odds Ratio of 4.56, 95% Confidence Interval 3.42-6.42. A further 34 smears classified as unsatisfactory due to degeneration (19), insufficient squamous cells (7), inflammatory exudate (4), excess blood (3) and a thick slide (1).

Conclusions
The cytobrush is significantly more efficacious than the Ayre spatula in obtaining adequate cervical smears. Use of the cytobrush will ensure less repeat smears.