The relation between eight specific colposcopic diagnostic findings and the histologic grade of a cervical lesion in 896 women was evaluated. The size of the transformation zone (TZ), the size of the lesion, the intensity of the color tone, distinct margins, the pathology of the vessels, and the presence of micropapillae as single findings were highly statistically correlated to the histologic grade (P < 0.0001). By logistic regression analysis the risk for a higher histologic grade when assessed by colposcopy was greatest in women with variation of the acetowhite color (odds ratio (OR) = 16.0; 95% CI, 10.0-26.0) followed by coarse vessels (OR = 10.0; CI, 3.2-34.0). Lesion-size larger than 50% of the visible cervix had an OR of 3.6 (CI, 2.1-6.3). Extention beyond TZ had an OR of 0.4 (CI, 0.2-0.4) and larger TZ had an OR of 0.5 (CI, 0.3-0.9). In conclusion we found that the size of the cervical lesion had some independent predictive value and should be considered in future trials.