Knowledge of stroke risk factors, warning symptoms, and treatment among an Australian urban population.

BACKGROUND AND PURPOSE: Reduction in the risk of stroke and increase in the speed of hospital presentation after the onset of stroke both depend on the level of knowledge of stroke in the general population. The aim of the present study was to assess baseline knowledge regarding stroke risk factors, symptoms, treatment, and information resources. METHODS: A community-based telephone interview survey was conducted in the Newcastle urban area in Australia. A total of 1278 potential participants between the ages of 18 to 80 were selected at random from an electronic telephone directory. A trained telephone interviewer conducted a telephone survey using the Computer-Assisted Telephone Interviewing (CATI) program. RESULTS: A total of 822 participants completed the telephone interview. Six hundred three participants (73.4%) correctly identified the brain as the affected organ in stroke. The most common risk factors for stroke identified by respondents were smoking (identified by 324 [39.4%]) and stress (identified by 277 [33.7%]). The most common warning sign of stroke described by respondents was "blurred and double vision or loss of vision in an eye," listed by 198 (24.1%). A total of 626 (76.2%) respondents correctly listed >/=1 established stroke risk factor, but only 409 (49.8%) respondents correctly listed >/=1 warning sign. CONCLUSIONS: The level of knowledge in the community of established stroke risk factors, warning signs, and treatment as indicated by this survey suggests that a community-based education program to increase public knowledge of stroke may contribute to reducing the risk of stroke and to increasing the speed of hospital presentation after the onset of stroke.

Hereditary nonpolyposis colorectal cancer in 95 families: differences and similarities between mutation-positive and mutation-negative kindreds.

Hereditary nonpolyposis colorectal cancer (HNPCC) describes the condition of a disparate group of families that have in common a predisposition to colorectal cancer in the absence of a premalignant phenotype. The genetic basis of this disease has been linked to mutations in genes associated with DNA mismatch repair. A large proportion of families harbor changes in one of two genes, hMSH2 and hMLH1. Approximately 35% of families in which the diagnosis is based on the Amsterdam criteria do not appear to harbor mutations in DNA-mismatch-repair genes. In this report we present data from a large series of families with HNPCC and indicate that there are subtle differences between families that harbor germline changes in hMSH2 and families that harbor hMLH1 mutations. Furthermore, there are differences between the mutation-positive group (hMSH2 and hMLH1 combined) of families and the mutation-negative group of families. The major findings identified in this study focus primarily on the extracolonic disease profile observed between the mutation-positive families and the mutation-negative families. Breast cancer was not significantly overrepresented in the hMSH2 mutation-positive group but was overrepresented in the hMLH1 mutation-positive group and in the mutation-negative group. Prostate cancer was not overrepresented in the mutation-positive groups but was overrepresented in the mutation-negative group. In age at diagnosis of colorectal cancer, there was no difference between the hMSH2 mutation-positive group and the hMLH1 mutation-positive group, but there was a significant difference between these two groups and the mutation-negative group.

The eicosapentaenoic to docosahexaenoic acid ratio of diets affects the pathogenesis of arthritis in Lew/SSN rats.

Dietary-induced changes in tissue levels of polyunsaturated fatty acids modify inflammatory reactions through changes in the synthesis of lipid and peptide mediators of inflammation. Four semipurified 20% fat diets, based on beef tallow (BT), safflower oil (SFO), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were provided. The DHA and EPA ratios of the (n-3) fatty acid-based diets were 1.1 and 3.4, respectively. The effect of prefeeding diets differing in EPA to DHA ratios prior to the induction of streptococcal cell wall (SCW) arthritis in female Lew/SSN rats was examined. Weanling rats were fed diets for 5 wk before arthritis induction and 5 wk post-arthritis induction. Footpad thickness, hock circumference, plasma and macrophage fatty acids and histological assessment were compared. There were no differences in food intake and final body weights among the groups. Footpad inflammation, reported as percentage change (adjusted for growth) was greatest for rats fed the BT-based diet, intermediate in those fed the SFO-based diet and least for the rats fed the EPA- and DHA-based diets (P < 0.05). Macrophage phospholipids revealed cellular incorporation of EPA and DHA from the fish-oil based diets which modified lipid and peptide mediators of inflammation. Histological sections of rat hocks ranked by severity of arthritis-related changes suggested that the SFO- and EPA-based diets were more successful in ameliorating the destructive arthritic phase in hock joints than the BT- and DHA-based diets (P = 0.09) in this model of arthritis. The course of SCW-induced arthritis can be altered by diet-induced changes in macrophage fatty acid composition. The EPA-based diet is more effective in suppression of inflammation than the DHA-based diet.

Use of conditional and marginal odds-ratios for analysing familial aggregation of binary data.

We propose a method for measuring familial aggregation of binary outcomes that incorporates unconditional, i.e., marginal, odds-ratios, for measuring association between outcomes within generations while using conditional odds-ratios to measure association between generations. This method may be used together with marginal odds-ratio models to explore the strength of association between individuals within a generation while accounting for the outcomes of predecessors. Interpretation of resulting odds-ratios is straightforward and a number of features of the method are discussed. An example, using smoking status data from Busselton Health Study families, is used to illustrate our approach.

Adjustment for regression dilution in epidemiological regression analyses.

PURPOSE: The term "regression dilution" describes the dilution/attenuation in a regression coefficient that occurs when a single measured value of a covariate is used instead of the usual or average value over a period of time. This paper reviews the current knowledge concerning a simple method of adjusting for regression dilution in single and multiple covariate situations and illustrates the adjustment procedure. METHODS: Formulation of the regression dilution problem as a measurement error problem allows existing measurement error theory to be applied to developing methods of adjustment for regression dilution. This theory leads to a precise method of adjustment for linear regression and approximate methods for logistic and Cox proportional hazards regression. The method involves obtaining the naive estimates of coefficients by assuming that covariates are not measured with error, and then adjusting these coefficients using reliability estimates for the covariates. Methods for estimating the reliability of covariates from the reliability and main study data and a method for the calculation of standard errors and confidence intervals for adjusted coefficients are described. RESULTS: An illustration involving logistic regression analysis of risk factors for death from cardiovascular disease based on cohort and reliability data from the Busselton Health Study shows that the different methods for estimating the adjustment factors give very similar adjusted estimates of coefficients, that univariate adjustment procedures may lead to inappropriate adjustments in multiple covariate situations, whether or not other covariates have intra-individual variation, and when the reliability study is moderate to large, the precision of the estimates of reliability coefficients has little impact on the standard errors of adjusted regression coefficients. CONCLUSIONS: The simple method of adjusting regression coefficients for "regression dilution" that arises out of measurement error theory is applicable to many epidemiological settings and is easily implemented. The choice of method to estimate the reliability coefficient has little impact on the results. The practice of applying univariate adjustments in multiple covariate situations is not recommended.

Outcome measures in split mouth caries trials and their statistical evaluation.

The split mouth study design in trials of fissure sealants and restorative materials neatly controls for confounding by many of the variables associated with poor retention of sealants and occurrence of dental caries. Traditionally, the outcome measures used in split mouth trials have been material retention, (per cent) effectiveness and net gain. A survey of the literature revealed that a large proportion of split mouth studies report no statistical evaluation of outcome measures. In those studies in which statistical evaluation had been conducted, McNemar's X2 was the test most frequently used. This statistic is appropriate for comparing differences between "success" and "failure" tooth pairs (or "positives" and "negatives" in split mouth terminology) but it cannot evaluate directly effectiveness and net gain. The distributions of effectiveness and net gain are different and it would be desirable to estimate confidence intervals for them. In this paper, we consider these statistics, suggest methods by which confidence intervals may be calculated, and provide examples of the calculations. We demonstrate the close relationship between effectiveness (as used in split mouth trials) and relative effect and relative risk (as used in general epidemiological analysis) and recommend that relative risk should be the preferred outcome measure for split mouth trials. Whatever outcome measure is chosen in split mouth trials should always be subjected to statistical evaluation, preferably by the calculation of confidence intervals.

Media relations: clues for improvement.

A nationwide survey of media representatives in television, radio, and newspapers investigated their perceptions about health care executives and health care system. Major findings include media perceptions about the trustworthiness of health care executives and the priority of and future plans for health care coverage. Critical problems while interacting with health care executives were also identified by the media and are discussed. Finally, suggestions for improving the health care executive-media relationship are given.

Hospital study reveals strategies for improving media relations.

A nationwide study revealed that hospital administrators feel inadequate when dealing with the media, and also think the media does not understand the hospital business. Many strategies are available to counter these problems, including some that emphasize issues related to bed size.

Dealing with the media: CEOs' perceptions.

Health care executives' greatest concern in dealing with journalists is what they perceive as the media's lack of information and lack of understanding of health care issues. According to a survey to which 175 institutions responded, administrators perceive that they are not well prepared to deal with the media, they fear being quoted out of context, and they exhibit a lack of trust in the media. When the study data were examined according to hospital size and the presence or absence of a public relations function, the following relationships were observed: CEOs in large institutions are more likely than CEOs in smaller institutions to perceive that the media misunderstand health care issues. The degree to which lack of trust in the media and quoting out of context were cited as problems declines as bed size increases. The presence of a public relations function in the institution does not eliminate CEO's perceptions of miscommunication. Providers must take a strong stance in addressing the potential problems highlighted in the study. Seminars and printed materials should be created to update the media on current issues and to foster a sense of cooperation between the parties. Executives themselves must take advantage of continuing education programs that focus on developing communications skills. Efforts to resolve these problems are imperative, since continued dissatisfaction with the media ultimately will result in a misinformed or uninformed public.