Seventy-two thousand and six hundred and forty-four cervical smears were evaluated in the Hospital Nacional Docente Madre Niño San Bartolomé, Lima, in order to determine the quality of samples stained with PAP. The smears were collected from 5 different healthcare districts and an analytical-correlational prospective and cross-sectional study was designed to assess them. Cytological processing was performed in accordance with international requirements for cytology, and cytological interpretation was performed according to the Bethesda system.Of 72,644 cervical smears evaluated by Bethesda system, 2,615 samples (3.6 %) had inadequate sample (IM > 75 %) mainly due to the presence of leucocytes (49 %), low cellularity (24 %) or insufficient fixation (20 %). The Youden index was 0.7 for IM, varying significantly from the negative for intraepithelial lesions or malignancy (P = .71). Health districts Rímac, Túpac-Amaru, Lima and Puente Piedra accounted for 849 (33 %), 723 (28 %), 675 (25 %) and 365 (14 %) of IM, respectively. A statistically significant direct correlation between the place of origin of the smears and the number of IM was found (P < .005; rho = .492). The quantity of cervical smears with IM or low quality surpassed that established by various international bodies and the proportion of non-neoplastic findings was high whilst squamous epithelial and glandular abnormalities were within average range.Quality assessment is necessary in every phase of cytological screening if it is to prove efficient and comply with international quality requirements and accreditation as well as achieving continuous improvement.