PubMed · 9762511
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
M Szklo. 1998. Population-based cohort studies.. https://doi.org/10.1093/oxfordjournals.epirev.a017974
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
As part of an ongoing cohort study in the Hokuriku region of Japan, cervical cell samples from histologically confirmed normal (n = 114) or abnormal (n = 286) women were examined for the presence of HPV DNA using a second-generation hybrid capture assay (HCA-II) and LCR-E7 PCR. HCA-II detected low-risk (HPV-6, -11, -42, 43 and -44) and high-risk (HPV-16, -18, -31, -33, -35, -39, -45, -51, -52, -56, -58, -59 and -68) HPV types, while LCR-E7 PCR detected an additional 7 HPV types and some uncharacterized types. In screening of high-grade squamous intraepithelial lesions (HSILs) and invasive cervical cancer, the sensitivities of HCA-II and LCR-E7 PCR testing the high-risk HPV types were 83% and 81%, respectively, while the specificity of both assays was 93%. The sensitivity of LCR-E7 PCR increased to 87%, which was significantly higher than that in HCA-II, when testing both high-risk and other HPV types. Sixty-eight inconsistent results (17% of total tested) from HCA-II and LCR-E7 PCR were due to (i) low copy number of HPV genome (false-negative for HCA-II, 5.3% and for LCR-E7 PCR, 1.3%), (ii) infection with HPV types undetectable by HCA-II (4.8%), (iii) multiple HPV infections (5%) or (iv) unknown reasons (0.8%). LCR-E7 PCR revealed that infections with HPV-16, -18, -31, -33, -35, -51, -52, -56, -58 or -67 was a high risk for cancer since these types predominated in HSIL and invasive cervical cancer. Samples showing high relative light units (>20) with a high-risk probe in HCA-II also gave positive results in LCR-E7 PCR and were generally associated with abnormal cervical lesions. Thus, we propose that both HCA-II and LCR-E7 PCR are valuable screening tests for premalignant and malignant cervical lesions.
Explore the source record for details and available documents.
Once a new vaccine has been licensed and is in widespread use, it is important to be able to detect and investigate adverse events which may be associated with the vaccine. This is particularly important for rare events which may have been missed in pre-licensure studies. Recent studies investigating adverse events following vaccination have used either a population or a sample of the population (cohort studies), cases matched to controls (case-control studies), or just information on the cases themselves (self-controlled case-series studies). In this paper, the three methods are reviewed and compared and examples are given of recent applications. The effects of potential sources of bias are demonstrated using a data set on MMR vaccine and convulsions.