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Background:Identification of human papillomavirus type 16 (HPV16) as the major risk factor for cervical neoplasia, and mass production of DNA free HPV capsids have paved the way to preventive vaccination trials. Design of such trials requires reliable attack rate data.Objective:Determination of (1) HPV16 and (2) cervical neoplasia attack rates in primiparous women. Estimation of actuarial sample sizes for HPV16 vaccination phase IV trials.Design:A longitudinal cohort study.Methods:Population based Finnish Maternity Cohort (FMC) and Finnish Cancer Registry (FCR) were linked for the identification of two cohorts of primiparous women: (1) a random subsample of the FMC: 1656 women with two pregnancies between 1983-9 or 1990-6 and living in the Helsinki metropolitan area, and (2) all 72 791 primiparous women living in the same area during 1983-94. Attack rate for persistent HPV16 infection (1) was estimated in 1279 seronegative women by proportion of seroconversions between the first and the second pregnancy. Comparable 10 year cumulative incidence rate (CR) of cervical intraepithelial neoplasia grade III and cervical cancer (CIN III+) (2) was estimated based on cases registered at the FCR during 1991-4.Results:The HPV16 attack rates were 13.8% (<18 years), 7.0% (18-19 years), 2.3% (21 years), 2.4% (23 years), and 4.5% (<25 years). Number of vaccinees required for a 5 year efficacy trial with persistent HPV16 infection as the end point ranged between 1000 and 3900, assuming 80% power, 90%-70% vaccine efficacy (VE), and misclassification. The CRs of CIN III+ were 0.33% (<18 years), 0.44% (18-19 years), 0.21% (20-24 years), and 0.28% (<25 years). Number of vaccinees required for a 10 year efficacy trial with HPV16 positive CIN III+ as the end point was 15 000 assuming 80% power, 90% VE, and 75% aetiological fraction of CIN III+ for HPV16.Conclusions:The attack rates of HPV16 and CIN III+ identify primiparous women under 25 years of age among target populations for postnatal HPV vaccination at phase II/III trials.

The diagnostic accuracy of detailed zonography using the Scanora multimodal X-ray system was compared with that of periapical radiography. The study was based on the detection of periapical bone lesions at 259 dental sites distributed evenly throughout the dentitions of 164 patients. Each site was examined by periapical radiography and zonography, in parallel. The zonograms consisted of four detailed images that could also be read as stereopairs, in either the horizontal or vertical direction. Five observers evaluated the sites for the presence or absence of periapical osteolysis or sclerosis and apical widening of the periodontal ligament space for the whole dentition, and for three dental regions. ROC analysis revealed no significant overall or regional differences between the diagnostic accuracies of the periapical and zonographic techniques, regardless of whether the zonograms were read as sets of four images (multiview) or stereoscopic images. The sensitivity of periapical radiography was 72%, that of multiview zonography 88%, and that of stereoscopic zonography 85%. Specificities were 93%, 84% and 89%, respectively. The energy imparted during detailed zonography was 0.98 mJ. It is concluded that zonography is as good as periapical radiography for the detection of periapical pathology.

The diagnostic performance of the detailed narrow-beam (DNB) technique of the Scanora multimodal X-ray system was compared with periapical radiography for detecting periodontal pathology. In total, 253 sites in 133 patients were examined. Receiver operating characteristics (ROC) of both imaging modalities were analyzed in relation to the ratings of five observers for the whole dentition, three dental regions and five types of periodontal lesion. ROC analysis demonstrated that the overall diagnostic performance of DNB radiography was better (P < 0.05) than that of periapical radiography. DNB radiography was significantly superior (P < 0.01) for detecting marginal widening of periodontal membrane space, but there was no significant difference between the two techniques for crestal erosion, vertical bone loss, furcation involvement or calculus. The regional differences found in overall diagnostic performance of the two imaging modalities were not significant. The sensitivity for periapical radiography was 71% and for DNB radiography 85%, and the specificities 82% and 81% respectively. It is concluded that DNB radiography is a good radiographic examination for periodontal disease, and an acceptable alternative to periapical radiography.

The diagnostic performance of the detailed narrow-beam (DNB) technique of the Scanora multimodal radiography system was compared for periapical radiography for the detection of periapical bone lesions at 262 dental sites in 144 patients. Receiver operating characteristics (ROC) of both imaging modalities were analysed in relation to the ratings of five observers for the whole dentition, three dental regions, and two types of periapical lesions. ROC analysis demonstrated no overall or regional significant differences in the diagnostic performance of the two imaging modalities. The sensitivity for periapical radiography was 72% and for DNB radiography 90%, and the specificities 89% and 88%, respectively. It is concluded that DNB radiography performs as well as periapical radiography for detecting periapical bone lesions.

BackgroundThe aim of the study was to analyse the pattern of lung cancer mortality from 1960 to 1989 and to predict lung cancer mortality for 1990–1999 for males and females aged ≥ 30 years in the Czech and Slovak Republics. MethodThe mortality pattern of lung cancer was examined and predicted using republic-age-period-cohort models. ResultsTrends in lung cancer mortality were upward for both sexes over the study period. In the early 1960s, lung cancer mortality in Slovak males was much lower than that in Czech males, but since the late 1960s lung cancer mortality in males increased more rapidly in Slovakia than in the Czech Republic. It was predicted that mortality due to lung cancer in Slovak males would exceed that in Czech males during the last 5 years of the 20th century. Slovak female lung cancer mortality was lower than that for Czech females throughout the study period, and the trends in both republics were similar.