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Studies have shown that Liquid Based Pap Tests increase detection of precancerous cells over the conventional smear based glass slide Pap smear.

The Liquid Based Pap Test is the most widely used method for cervical cancer screening in the United States. It was developed to address the limitations of the conventional Pap smear, and after rigorous clinical trials, it was approved by the U.S. Food and Drug Administration (FDA) as a replacement for the conventional Pap smear. The Liquid Based Pap Test is a cytology method approved by the FDA found to be "significantly more effective" than the conventional Pap smear for detection of cervical abnormalities.

Most importantly, since FDA approval, more than 170 studies have been published, in peer-reviewed medical journals, demonstrating a wide range of clinical benefits of the Liquid Based Pap Test including increased disease detection, reduction of equivocal diagnoses, improved specimen adequacy and the ability to perform additional tests out of the same vial. Liquid based Pap Tests , after proper validation, are currently approved by the FDA for a variety of out of the vial tests, including HPV, CT, NG, and HSV as well as any potential agent that is DNA based and can be identified using sophisticated DNA testing.

To date there have been more than 30 studies published in peer-reviewed journals, reporting on nearly 400,000 patients that show a significant increase in the detection of both low grade and high grade lesions using the Liquid based Pap Tests compared to the conventional Pap smear.

Liquid Based Process
1. Dispersion: Randomizes/homogenizes patient population within the vial.
2. Cell Collection: software monitors the flow rate and senses when pores are blocked by material (red blood cells [RBCs], white blood cells [WBCs], and epithelial cells).
3. Cell Transfer: Cylinder is inverted and filter comes in contact with glass slide. Air pressure from behind the filter aids the cell's natural attraction to the glass slides.

Clinical Studies
IMPROVES SAMPLE QUALITY AND DETECTION OF ABNORMALITIES OVER CONVENTIONAL PAP SMEARS.*

Method:
Meta-analysis of 25 articles published between 1990-2000 comparing diagnostic cytology and specimen adequacy of the two tests for 67,484 patients.

Findings:
Odds ratios favored the Liquid Based Pap Tests over the conventional Pap smear in regard to the diagnosis of LSIL and HSIL; adequacy was improved in the Liquid Based Pap Test group in all trials.

* Bernstein SJ, Sanchez-Ramos L, Ndubisi B. Liquid-based cervical cytologic smear study and conventional Papanicolaou smears: A metaanalysis of prospective studies comparing cytologic diagnosis and sample adequacy. Am J Obstet Gynecol. 2001;185:308-317.

Conventional Pap Smear

Microscopically, the uneven distribution of cellular material associated with the Conventional Pap Smear pattern is evident.

Liquid Based Pap Test

This slide is the from the same patient as the slide above. Tissue architecture is maintained. Liquid based technology rearranges the relationship of cell groups on the glass slide. A group/sheet of endocervical cells present represents this.