Use of an artificial neural network in estimating prevalence and assessing underdiagnosis of asthma

An artificial neural network was trained in the recognition of asthmatics in a general practice population, employing crossvalidation on a subset of 350 patients of known asthmatic status. The trained network was then run on the data from 3139 patients whose asthmatic status was unknown. Using the values from the test set as estimates of sensitivity and specificity, the number predicted positive was adjusted to allow for false positives and false negatives to give an estimate of asthma prevalence and the minimum underdiagnosis rate that this suggested for the population. Using different data sets and network structures, prevalence rates of approximately 16–21% were measured providing evidence, even after allowing for maximum variablity in the estimates, consistent with under-diagnosis of at least a small percentage (0.7–4.0%). To provide a more precise estimate of the rate of this under-diagnosis and associated prevalence, a larger training and testing set of more accurately labelled cases is planned.     

Cross-Sectional Study On,The Health Effects Of Gas Cooking Stoves In Japan

In order to investigate the health effects of NO₂, emitted from gas cooking stoves, we compared the prevalence of several respiratory symptoms for people living in gas homes (homes with gas cooking stoves) with those for people living in electric homes (homes with electric cooking stoves) in Japan. The survey was conducted in September 1985, with a self-administered questionnaire. No statistically significant differences were found for several respiratory symptoms between electric homes and gas homes among both children (adjusted odds ratios: 0.64–1.80) and their parents (odds ratios: 0.39–0.94). This work represents a preliminary study in Japan. A longitudinal study should be conducted to further investigate the health effects associated with gas cooking stoves.     

德阳地区晒烟病毒种类及发生规律研究

病毒病在德阳晒烟上每隔1-2年大发生一次,造成重大经济损失。1989-1991年,采用ELISA等手段,鉴定了该地区晒烟病毒标样722个。结果表明,烟草普通花叶病毒(TMV)、黄瓜花叶病毒(CMV)、马铃薯病毒Y(PVY)是晒烟上的3种主要病毒。在不同年份或同一年份的不同时期,这3种病毒发生的比例各不相同。重病年以蚜传的CMV、PVY为主。烟草病毒病流行与否与2、3月的气温及雨日关系密切。调查了该地区的毒源植物,提出了以治蚜避蚜、提高烟株抗病力为中心的综合防治措施,取得了明显的防治效果。      

Systemic,environmental and lifestyle risk factors for dry eye disease in a mediterranean caucasian population

ObjectivesTo assess systemic, environmental and lifestyle risk factors for dry eye disease (DED) in a Mediterranean Caucasian population.MethodsA cross-sectional study was performed on 120 Caucasian participants aged between 18 and 89 years (47.0 ± 22.8 years). Medical history, information regarding environmental conditions and lifestyle, Ocular Surface Disease Index, Dry Eye Questionnaire-5, non-Invasive (Oculus Keratograph 5 M) breakup time, tear film osmolarity and ocular surface staining parameters were assessed in a single clinical session to allow DED diagnosis based on the guidelines of the Tear Film and Ocular Surface Society Dry Eye Workshop II Diagnostic Methodology Report. A multivariate logistic regression model was constructed including those variables with a p-value less than 0.15 in the univariate analysis.ResultsA prevalence of 57.7 % for DED was found. No age differences were found between those with and without DED (U = 1886.5, p = 0.243). Nevertheless, the DED group had more females (X² = 7.033, p = 0.008). The univariate logistic regression identified as potential risk factors for DED the following: female sex, sleep hours per day, menopause, anxiety, systemic rheumatologic disease, use of anxiolytics, daily medication, ocular surgery, poor diet quality, more ultra-processed food in diet, not drinking caffeine and hours of exposure to air conditioning per day. Multivariate logistic regression revealed that hours of sleep per day, menopause and use of anxiolytics were independently associated with DED (p ≤ 0.026 for all).ConclusionsDED is associated with systemic, environmental and lifestyle risk factors. These findings are useful to identify potentially modifiable risk factors, in addition to conventional treatments for DED.     

Developing explicit risk models for predicting low-back disability: A statistical perspective

Despite extensive research efforts, disability due to work-related low-back disorders continues to pose a significant economic burden to industry, and significant pain and economic loss to workers. Numerous epidemiological studies have been conducted, but many of these studies have resulted in qualitative guidelines rather than explicit quantitative guidelines. Furthermore, there is considerable disagreement and controversy concerning the validity of manual materials handling criteria based on biomechanical, physiological, and psychophysical theory and research. There is a pressing need for epidemiological field evaluation of such criteria, as well as epidemiologically-based models that provide estimates of low-back disability risk given a set of task, workplace and worker characteristics. A critical tool in such investigations is the statistical method chosen to model risk. The statistical appropriateness of previously used methods are reviewed and critiqued. A fairly comprehensive discussion of the statistical models available for modeling disability risk is then presented, with a focus on models that provide explicit estimates of risk. Recent advances in computer speed have significantly advanced the power and flexibility of statistical modeling techniques. These techniques have the potential to provide considerable insight into the etiology of low-back disability and to provide explicit quantitative design criteria for the ergonomics practitioner.Relevance to industryStatistical methods available for modeling the risk of low-back disability are discussed and previous methodologies used are critiqued. The methods discussed will aid researchers conducting epidemiological studies of low-back disorders in industry, and the discussion of these methods will aid practitioners faced with interpreting results of previous studies.     

Modifiable lifestyle risk factors for dry eye disease

PurposeTo examine the association between modifiable lifestyle factors and dry eye disease.MethodsThree hundred and twenty-two community residents (186 females, 136 males; mean ± SD age, 41 ± 22 years) with no major systemic or ophthalmic conditions (other than dry eye disease) were recruited in a cross-sectional study. A lifestyle factor questionnaire was administered, and dry eye symptomology, ocular surface characteristics, and tear film quality were evaluated for each participant within a single clinical session, in accordance with the global consensus recommendations of the TFOS DEWS II reports.ResultsA total of 111 (34 %) participants fulfilled the TFOS DEWS II diagnostic criteria for dry eye disease. Multivariate regression analysis demonstrated that advancing age, female sex, East Asian ethnicity, and increased digital screen exposure time were positive risk factors for dry eye disease (all p < 0.05), while increased caffeine consumption was a protective factor (p = 0.04).ConclusionsIncreased digital screen exposure time and reduced caffeine consumption were modifiable lifestyle factors associated with higher odds of dry eye disease. These findings might contribute to informing the design of future prospective research investigating the efficacy of preventative intervention and risk factor modification strategies.     

Development and evaluation of evidence-based guidelines on contact lens-related microbial keratitis.

PURPOSE: To assess the response to clinical guidelines based on recent epidemiological studies of contact lens-related microbial keratitis. METHODS: Incidence rates for silicone hydrogel extended wear were summarized from recent studies. Risk factors were listed and two key factors identified: overnight wear and poor hygiene accounting for 43% and 33% of risk, respectively. A pre-guidelines, web-based survey was conducted to assess the need for information and level of knowledge on CL-related microbial keratitis (n=162). Comparisons to a post-guidelines survey (n=51) measured whether new information was acquired through an educational brochure posted to the membership. RESULTS: In the pre- and post-guidelines surveys, 52% (85/162) vs. 43% (22/51, p=0.3) indicated they did not have enough information on CL-related microbial keratitis. The importance attached to risk factors was generally reflective of the magnitude of risk and practitioners made appropriate recommendations about low risk modalities. Hygiene practices were rated as highly important in both surveys (>90%) with increased awareness of handwashing (p=0.03). Overnight wear of hydrogel lenses was considered highly important in 94% (201/213). However, despite evidence to the contrary, only 53% in the pre-guidelines and 58% in the post-guidelines surveys indicated that silicone hydrogel overnight wear was a highly important risk factor. CONCLUSIONS: Research evidence has been disseminated to the BCLA membership and responses gathered via a web survey. There are some areas of disconnect between practitioner opinion, as gauged in this survey, and the evidence from the research, particularly with regards to increased risk with overnight wear.     

Outbreak of Haff Disease caused by consumption of crayfish (Procambarus clarkii), Nanjing,Jiangsu Province,China

Haff disease is a rare syndrome characterized by rhabdomyolysis following consumption of cooked fish or crustaceans. We present the investigation of an outbreak of Haff disease in Nanjing, Jiangsu Province, China incorporating both epidemiological and chemical analysis. Structured questionnaires were sent to 20 case-patients and 25 diners who ate with case-patients. Eleven samples of crayfish (Procambarus clarkii) from the local markets, blood and urine samples from two case-patients were collected and sent for chemical testing. The case-control study revealed that all cases and controls had eaten crayfish during the exposure period. Consuming more than 10 pieces of crayfish was related to increased disease risk (p < 0.001). Chemical analysis of crayfish, blood and urine samples did not show any possible toxins, drugs and hazardous elements. This 2010 Nanjing outbreak of Haff disease was attributed to the consumption of crayfish. Improved surveillance and understanding of etiology should help further our understanding of this disease and improve management of future disease outbreaks.