Small proportions: what to report for confidence intervals?

The original article to which this Erratum refers was published in Pharmacoepidemiology and Drug Safety 2005; 14: 239–247.     

Case-control study of risk factors for cervical neoplasia in Denmark. II. Role of sexual activity,reproductive factors,and venereal infections

Sexual, reproductive and venereal risk factors for cervical neoplasia were investigated in a population-based case-control study of 586 women with histologically verified, cervical squamous-cell carcinoma in situ, and 59 women with invasive squamous-cell cervical cancer, diagnosed from 1985 to 1986 in Copenhagen. Cases were identified from the computerized Danish Cancer Registry. An age-stratified control group (n=614) was drawn at random from the female population in the study area by means of the Danish Central Population Register. A structured questionnaire was mailed to cases as well as controls. Increasing number of sexual partners exerted a significant effect on the risk both for carcinoma in situ, and invasive cancer, independently of age at first intercourse and other potential confounders. Conversely, the association with early age at first intercourse became statistically insignificant after allowance for other risk factors, although an increasing risk was still observed with decreasing age at sexual debut. Early age at first episode with genital warts was a significant risk factor for carcinoma in situ, perhaps indicating a possible increased susceptibility of the cervix epithelium during adolescence. A history of genital warts was a good predictor of risk for carcinoma in situ, whereas a history of previous gonorrhea was associated with an increased risk for invasive carcinoma. Women with multiple births had a significantly increased adjusted risk, especially for carcinoma in situ, although some association was also observed with invasive cervical cancer. The study supports the hypothesis of cervical neoplasia being a sexually transmitted disease, and that carcinoma in situ and invasive cervical carcinoma, to a high degree, have similar patterns of risk factors.Drs Kjaer, Engholm, and Lynge are with the Danish Cancer Registry. Dr Dahl is with the Department of Surgery, Slagelse Hospital, Denmark. Dr Bock is with the Department of Gynecology, Rigshospitalet, Copenhagen, Denmark. Dr Jensen, formerly with the Danish Cancer Registry, is deceased. Address correspondence to Dr Kjaer, Danish Cancer Registry, Institute of Cancer Epidemiology, Danish Cancer Society, Rosenvengets Hovedvej 35, Box 839, Copenhagen. Denmark. The Danish Cancer Society supported this study through grants.     

Comparison studies of HPV detection in areas at different risk for cervical cancer.

The hypothesis of a geographical correlation between HPV detection rates and incidence of cervical cancer has been investigated in studies of various types. However, results from these studies are equivocal, in contrast to findings concerning other suspected risk factors which seem to correlate well with the cervical cancer incidence. Possible explanations include (1) greater sensitivity of ecological studies to cumulative exposures such as lifetime number of sexual partners, lifetime smoking and seroprevalence of herpes simplex virus type 2, than to HPV DNA prevalence which does not reflect cumulative exposure to HPV and (2) misclassification in the HPV diagnosis leading to wrong prevalence estimates. In future research, it will be important to establish the sensitivity and specificity of the different methods and conduct intra- and interlaboratory validation studies in order to standardize methods. In spite of the limitations of cross-sectional studies, the measurement of HPV prevalence and its correlation with, for example, sexual behaviour is still valuable for our understanding and interpretation of the role of HPV infections.     

Lipopolysaccharide contamination of beta-lactoglobulin affects the immune response against intraperitoneally and orally administered antigen

BACKGROUND: Microbial components in the environment are potent activators of the immune system with capacity to shift the active immune response towards priming of Th1 and/or Th2 cells. Lipopolysaccharide (LPS), a cell-wall component of Gram-negative bacteria, is extensively present in food products like cow's milk. It is not well established, however, how this presence of LPS affects oral tolerance induction. METHODS: We studied the effect of LPS contamination in a commercial preparation of the cow milk protein beta-lactoglobulin (beta-LG) on antigen-specific immune responses. IgG1/IgG2a production upon intraperitoneal immunization without adjuvant was measured, and oral tolerance induction against beta-LG after administration of either an aqueous solution or water-in-oil (w/o) emulsion of beta-LG was evaluated. RESULTS: LPS contamination of beta-LG provoked a beta-LG-specific IgG2a response, as well as an enhanced beta-LG-specific IgG1 response upon intraperitoneal immunization. Oral tolerance induction to beta-LG was induced by aqueous solutions of beta-LG with and without LPS administration. Conversely, oral administration of w/o-emulsified beta-LG prevented oral tolerance to beta-LG only when the beta-LG was contaminated with LPS. CONCLUSIONS: LPS contamination of an aqueous protein solution does not affect oral tolerance induction, whereas LPS present in emulsion prevents oral tolerance induction towards the food protein.     

Limb anomalies: Developmental and evolutionary aspects

In this review we describe the developmental mechanisms involved in the making of a limb, by focusing on the nature and types of interactions of the molecules that play a part in the regulation of limb patterning and characterizing clinical conditions that are known to result from the abnormal function of these molecules. The latter subject is divided into sections dealing with syndromal and nonsyndromal deficiencies, polydactylies, and brachydactylies. Conditions caused by mutations in homeobox genes and fibroblast growth factors and their receptor genes are listed separately. Since the process of limb development has been conserved for more than 300 millions years, with all the necessary adaptive modifications occurring throughout evolution, we also take into consideration the evolutionary aspects of limb development in terms of genetic repertoire, molecular pathways, and morphogenetic events.     

Interaction analysis of physician-patient communication: the influence of trait anxiety on communication and outcome

Little attention has been paid to how patients' personality traits interfere with the communication and the outcome of physician-patient interaction. We performed an experimental study with students with high and low trait anxiety as patients. One physician conducted a single consultation with 41 students applying two beforehand-specified consultation styles. Patients completed questionnaires concerning emotional state and satisfaction. The actual content of the consultations was analyzed by Roter interaction analysis system (RIAS). The physician gave more biomedical information to low-anxiety students than high-anxiety students. Students who provided a lot of biomedical information themselves were less tense after the consultation. However, students with high anxiety were more dependent on the physician actively asking biomedical questions for them to be able to deliver that same information. In contrast to low-anxiety students, those with high anxiety were less satisfied after consultations involving many psychosocial questions posed by the physician and a good deal of emotional talk on their own part. Compared to low-anxiety students, students with high anxiety were less satisfied and tenser after consultations with much positive emotional talk on the part of the physician. We conclude that physicians and educators should be aware that psychological and emotional communication may be experienced as intrusive and inappropriate by patients with high trait anxiety when they present minor somatic problems.