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PubMedDate not supplied

Harmonization of methods for analysis of cholesterol oxides in foods--the first portion of a long road toward standardization: interlaboratory study.

A compilation of literature data on the content of cholesterol oxidation products (COP) in various food products and in blood demonstrates a large variation in content in products or tissues of very similar nature when analyzed in different laboratories according to a large number of methods. The lack of validated, internationally recognized methodology with published accuracy and precision has so far hindered such assessments. Hence an interlaboratory comparision of methodologies of COP analysis was undertaken on egg yolk powders (EYP), whole milk powders (WMP), skim milk powders (SMP), and lard (L). Each product type had one fresh sample (low) and one aged (high) in COP contents. A total of 17 sets of results on WMP, 15 on SMP and EYP, and 13 on L were compared. Overall results (mg/kg sample) varied extensively: Fresh EYP 0.72-265, aged EYP 2.51-361; fresh WMP 0.02-18.1, aged WMP 0.02-26.9; fresh SMP 0.02-6.51, aged SMP <0.01-6.51; fresh L 0.18-97, aged L 4.15-452. Some results were questioned, viz., those from laboratories not indicating substantial differences between samples "low" and "high" in total COP. Others were excluded because of lack of verification of identity of gas chromatographic peaks by mass spectrometry. Then a more narrow range of core results (mg/kg sample) was observed: Fresh EYP 5.69-29.5 sample, aged EYP 11.8-79.0; fresh WMP 0.12-1.76, aged WMP 1.17-13.7; fresh SMP <0.30-<1.21, aged SMP 0.30-2.26; fresh L 0.18-5.07, aged L 94.4-231. At a workshop discussing the results, numerous recommendations were made toward more reliable methodology for determination of COP in foods.

Cholesterol↗

PubMed2004

Generalizing disease management program results: how to get from here to there.

For a disease management (DM) program, the ability to generalize results from the intervention group to the population, to other populations, or to other diseases is as important as demonstrating internal validity. This article provides an overview of the threats to external validity of DM programs, and offers methods to improve the capability for generalizing results obtained through the program. The external validity of DM programs must be evaluated even before program selection and implementation are begun with a prospective new client. Any fundamental differences in characteristics between individuals in an established DM program and in a new population/environment may limit the ability to generalize.

Disease Management↗

PubMed2004

Epidemiology of breastfeeding: advances and multidisciplinary applications.

Advancing understanding of the importance of breastfeeding (BF) has required advances in application of epidemiologic methods to BF research. This chapter considers, in the context of BF epidemiology, how different research designs complement each other to establish firmer causal inferences, the need for multidisciplinary collaborations, and the application of powerful analytical methods to strengthen epidemiologic studies. A recent global meta-analysis of 47 studies documenting the inverse association between lifetime BF duration and breast cancer risk illustrates the value of longitudinal (cohort) studies to establish the temporal sequence of events and to rule out differential recall biases that can threaten the internal validity of case-control studies. The discovery of the transmission of human immunodeficiency virus (HIV) via human milk has led epidemiologists to provide important hypotheses to be tested at the molecular and cellular level and in turn test hypotheses generated in laboratory studies. Application of powerful statistical methods to BF epidemiology has helped strengthen causal inferences. A retrospective analysis of the 1976--1977 Malaysian Family Life Survey found interactive multivariate statistical models to better understand how different socioeconomic and cultural contexts modify the influence of BF on child health. Further, a study conducted in Cebu City, Philippines, demonstrated how structural equation models can be used to test the pathways through which proximate (e.g., BF) and distal (e.g., socioeconomic status) determinants affect child health after adjusting for reverse causality (i.e., child health influencing maternal BF choice). For ethical reasons, BF randomized controlled trials (RCTs) have seldom been conducted. Recent RCTs examining the link between BF peer counseling and BF outcomes in diverse settings provides a unique opportunity to firmly establish the causal inferences regarding BF and the prevention of diarrheal diseases. The value of rapid assessment anthropologic methods to guide development of peer counseling interventions subsequently tested through RCTs is presented. This chapter also illustrates how Cox regression and logistic regression can be applied to BF research.

Breast Feeding↗

PubMedDate not supplied

Gas chromatographic/mass spectrometric determination of 3-methoxy-1,2-propanediol and cyclic diglycerols, by-products of technical glycerol, in wine: interlaboratory study.

The aim of the present study was to provide the official wine control authorities with an internationally validated method for the determination of 3-methoxy-1,2-propanediol (3-MPD) and cyclic diglycerols (CycDs)-both of which are recognized as impurities of technical glycerol-in different types of wine. Because glycerol gives a sweet flavor to wine and contributes to its full-body taste, an economic incentive is to add glycerol to a wine to mask its poor quality. Furthermore, it is known that glycerol, depending on whether it is produced from triglycerides or petrochemicals, may contain considerable amounts of 3-MPD in the first case or CycDs in the second. However, because these compounds are not natural wine components, it is possible to detect glycerol added to wine illegally by determining the above-mentioned by-products. To this end, one of the published methods was adopted, modified, and tested in a collaborative study. The method is based on gas chromatographic/mass spectrometric analysis of diethyl ether extracts after salting out with potassium carbonate. The interlaboratory study for the determination of 3-MPD and CycDs in wine was performed in 11 laboratories in 4 countries. Wine samples were prepared and sent to participants as 5 blind duplicate test materials and 1 single test material. The concentrations covered ranges of 0.1-0.8 mg/L for 3-MPD and 0.5-1.5 mg/L for CycDs. The precision of the method was within the range predicted by the Horwitz equation. HORRAT values obtained for 3-MPD ranged from 0.8 to 1.7, and those obtained for CycDs ranged from 0.9 to 1.3. Average recoveries were 104 and 109%, respectively.

Diglycerides↗

PubMed2004

Does Cryotherapy Improve Outcomes With Soft Tissue Injury?

REFERENCE: Bleakley C, McDonough S, MacAuley D. The use of ice in the treatment of acute soft-tissue injury: a systematic review of randomized controlled trials. Am J Sport Med. 2004; 32:251-261. CLINICAL QUESTION: What is the clinical evidence base for cryotherapy use? DATA SOURCES: Studies were identified by using a computer-based literature search on a total of 8 databases: MEDLINE, Proquest, ISI Web of Science, Cumulative Index to Nursing and Allied Health (CINAHL) on Ovid, Allied and Complementary Medicine Database (AMED) on Ovid, Cochrane Database of Systematic Reviews, Cochrane Database of Abstracts of Reviews of Effectiveness, and Cochrane Controlled Trials Register (Central). This was supplemented with citation tracking of relevant primary and review articles. Search terms included surgery,orthopaedics,sports injury,soft tissue injury,sprains and strains,contusions,athletic injury,acute,compression, cryotherapy,ice,RICE, andcold. STUDY SELECTION: To be included in the review, each study had to fulfill the following conditions: be a randomized, controlled trial of human subjects; be published in English as a full paper; include patients recovering from acute soft tissue or orthopaedic surgical interventions who received cryotherapy in inpatient, outpatient, or home-based treatment, in isolation or in combination with placebo or other therapies; provide comparisons with no treatment, placebo, a different mode or protocol of cryotherapy, or other physiotherapeutic interventions; and have outcome measures that included function (subjective or objective), pain, swelling, or range of motion. DATA EXTRACTION: The study population, interventions, outcomes, follow-up, and reported results of the assessed trials were extracted and tabulated. The primary outcome measures were pain, swelling, and range of motion. Only 2 groups reported adequate data for return to normal function. All eligible articles were rated for methodologic quality using the PEDro scale. The PEDro scale is a checklist that examines the believability (internal validity) and the interpretability of trial quality. The 11-item checklist yields a maximum score of 10 if all criteria are satisfied. The intraclass correlation coefficient and kappa values are similar to those reported for 3 other frequently used quality scales (Chalmers Scale, Jadad Scale, and Maastricht List). Two reviewers graded the articles, a method that has been reported to be more reliable than one evaluator. MAIN RESULTS: Specific search criteria identified 55 articles for review, of which 22 were eligible randomized, controlled clinical trials. The articles' scores on the PEDro scale were low, ranging from 1 to 5, with an average score of 3.4. Five studies provided adequate information on the subjects' baseline data, and only 3 studies concealed allocation during subject recruitment. No studies blinded their therapist's administration of therapy, and just 1 study blinded subjects. Only 1 study included an intention-to-treat analysis. The average number of subjects in the studies was 66.7; however, only 1 group undertook a power analysis. The types of injuries varied widely (eg, acute or surgical). No authors investigated subjects with muscle contusions or strains, and only 5 groups studied subjects with acute ligament sprains. The remaining 17 groups examined patients recovering from operative procedures (anterior cruciate ligament repair, knee arthroscopy, lateral retinacular release, total knee and hip arthroplasties, and carpal tunnel release). Additionally, the mode of cryotherapy varied widely, as did the duration and frequency of cryotherapy application. The time period when cryotherapy was applied after injury ranged from immediately after injury to 1 to 3 days postinjury. Adequate information on the actual surface temperature of the cooling device was not provided in the selected studies. Most authors recorded outcome variables over short periods (1 week), with the longest reporting follow-ups of pain, swelling, and range of motion recorded at 4 weeks postinjury. Data in that study were insufficient to calculate effect size. Nine studies did not provide data of the key outcome measures, so individual study effect estimates could not be calculated. A total of 12 treatment comparisons were made. Ice submersion with simultaneous exercises was significantly more effective than heat and contrast therapy plus simultaneous exercises at reducing swelling. Ice was reported to be no different from ice and low-frequency or high-frequency electric stimulation in effect on swelling, pain, and range of motion. Ice alone seemed to be more effective than applying no form of cryotherapy after minor knee surgery in terms of pain, but no differences were reported for range of motion and girth. Continuous cryotherapy was associated with a significantly greater decrease in pain and wrist circumference after surgery than intermittent cryotherapy. Evidence was marginal that a single simultaneous treatment with ice and compression is no more effective than no cryotherapy after an ankle sprain. The authors reported ice to be no more effective than rehabilitation only with regard to pain, swelling, and range of motion. Ice and compression seemed to be significantly more effective than ice alone in terms of decreasing pain. Additionally, ice, compression, and a placebo injection reduced pain more than a placebo injection alone. Lastly, in 8 studies, there seemed to be little difference in the effectiveness of ice and compression compared with compression alone. Only 2 of the 8 groups reported significant differences in favor of ice and compression. CONCLUSIONS: Based on the available evidence, cryotherapy seems to be effective in decreasing pain. In comparison with other rehabilitation techniques, the efficacy of cryotherapy has been questioned. The exact effect of cryotherapy on more frequently treated acute injuries (eg, muscle strains and contusions) has not been fully elucidated. Additionally, the low methodologic quality of the available evidence is of concern. Many more high-quality studies are required to create evidence-based guidelines on the use of cryotherapy. These must focus on developing modes, durations, and frequencies of ice application that will optimize outcomes after injury.

Journal Article↗

PubMed2005

Using and interpreting analogue designs.

Researchers in rehabilitation counseling and disability studies sometimes use analogue research, which involves materials that approximate or describe reality (e.g., written vignettes, videotaped exemplars) rather than investigating phenomena in real-world settings. Analogue research often utilizes experimental designs, and it thereby frequently possesses a high degree of internal validity. Analogue research allows investigators to exercise tight control over the implementation of the independent or treatment variable and over potentially confounding variables, which enables them to isolate the effects of those treatment variables on selected outcome measures. However, the simulated nature of analogue research presents an important threat to external validity. As such, the generalizability of analogue research to real-life settings and situations may be problematic. These and other issues germane to analogue research in vocational rehabilitation are discussed in this article, illustrated with examples from the contemporary literature.

Humans↗

PubMed2004

Understanding exercise behavior among New Zealand adolescents: a test of the transtheoretical.

PURPOSE: To test the utility of applying the Transtheoretical Model (TTM) to adolescent exercise behavior. The purpose of Study 1 was a replication study to examine whether the TTM could predict exercise stage readiness in adolescents. The purpose of Study 2 was to test the model's internal validity to predict exercise stage transition. METHODS: For Study 1, students (n = 3972) from 13 high schools completed questionnaires corresponding the variables in the TTM (i.e., stage of exercise change, processes of change, self-efficacy and decisional balance). For Study 2, 1434 of those participants completed the stage of exercise change questionnaire 6 months later. These data were used to establish an exercise stage transition profile. RESULTS: Results from Study 1 showed large effects for self-efficacy, decisional balance and two behavioral processes (i.e., counter-conditioning and self-liberation). Study 2 showed that all TTM construct significantly predicted exercise stage transition. Large effects were found for the same variables as in Study 1. CONCLUSIONS: The TTM is a useful framework for understanding both exercise stage readiness and exercise stage transition in an adolescent population.

Adolescent↗

PubMedDate not supplied

[Assessment of neurobehavioral functions of workers exposed to low doses of metallic lead].

The effects of low-dose lead occupational exposure on neurobehavioral functions are still not well defined by international literature. The objective of this study is to assess by psychometric testing the presence of possible neuropsychological impairment in a group of male Italian workers with low blood lead levels in comparison to an adequate non exposed worker group. Given informed consent to take part to the study, all workers were interviewed about their working and clinical history and underwent determination of blood lead levels (PbB). An internationally validated computerized battery of psychometric tests and a standardized paper-and-pencil version of mood self-rating scale and WAIS-R Vocabulary subtest were also administered to the workers. Exposed workers had a geometric mean of PbB significantly higher than non exposed workers, but rather low (16.4 +/- 1.7 microg/dl). The results of psychometric tests were not significantly different between the two worker groups, even after adjusting for the main confounding factors. In workers exposed to low lead doses no neurobehavioral abnormalities were demonstrated by the administered psychometric test battery.

Adult↗

PubMed1992

Newer functional outcome measurements in juvenile rheumatoid arthritis: a progress report.

Development of health status questionnaires for pediatric patients with rheumatic disease presents special challenges. At this time, several investigators are actively involved in development of health status instruments which have demonstrated reliability and internal validity. I review these instruments and outline future studies needed for these instruments.

Arthritis, Juvenile↗

PubMed2005

[Effect of laparoscopic cholecystectomy on the quality of life of patients with uncomplicated socially disabling gallstone disease].

INTRODUCTION: The indication for cholecystectomy in symptomatic, uncomplicated gallstone disease varies in the literature, and there is no international consensus. In Denmark, laparoscopic cholecystectomy is recommended for patients with uncomplicated cholecystolithiasis and socially disabling pain. Postoperative health-related quality of life on this indication is unknown. MATERIALS AND METHODS: A prospective consecutive study was conducted. Patients with uncomplicated cholecystolithiasis and socially disabling pain were included and underwent laparoscopic cholecystectomy in the department of day surgery. All patients had uncomplicated gallstone disease. An internationally validated questionnaire, the Gastrointestinal Quality of Life Index (GIQLI), was completed one week before and six weeks after the operation. The questionnaire comprises 32 questions covering five items related to gastrointestinal disease, and each question is rated on a scale of 0 to 4 points. The maximum GIQLI score (GIQLI total) is 128 points (32 x 4 points) and represents the best possible health-related quality of life. RESULTS: 75 consecutive patients (62 women) underwent uneventful operations. All patients returned the pre- and postoperative questionnaire. The median age was 42 years (range 18-69), the median body mass index was 26 (19-39) and the median operation time was 56 minutes (24-130). The median GIQLI total scores were 99 (33-127) and 112 (82-128) before and after operation, respectively (P < 0.001). Scores on all five sub-items were significantly improved as well. CONCLUSION: Laparoscopic cholecystectomy improves the health-related quality of life six weeks after the operation in patients with socially disabling, uncomplicated cholecystolithiasis.

Adult↗

PubMed2005

[Evidence-based medicine in Spanish pediatric surgery reports].

INTRODUCTION: Pediatric surgical literature is characterized by a high prevalence of observational studies and a paucity of randomized controlled trial, comparing mainly medical therapies. AIMS: To asses scientific evidence level produced by spanish pediatric surgeons. MATERIAL AND METHODS: Articles reported in Cirugía Pediátrica, surgical reports in Anales Españoles de Pediatría, and reports from spanish authors published in the Journal of Pediatric Surgery, Pediatric Surgery International and European Journal of Pediatric Surgery, from 1997 to 2002. Internal validity was assessed through the critial guides from Sackett, and evidence level was classified through the Oxford Centre for Evidence Based Medicine classification. RESULTS: 94.5% on therapy reports, 61.5% on diagnosis, 83.3% on prognosis and 52.2% on risk factors or etiology, were classified as level 4 (descriptive studies). Only four randomized controlled trials were found, all of them comparing medical therapies (analgesia, antibiotics and surgical stress control). CONCLUSIONS: Our results are similar to those offered by previous reviews, showing up a low level of scientific evidence in most articles. Diffusion of guides on reporting descriptive studies may improve the evidence level of our reports.

Child↗

PubMed2005

[Therapy research in times of patient preference].

The Declaration of Helsinki bears the consequence that in the future reference-controlled clinical trials will increasingly replace placebo-controlled trials. This has enormous implications on research in complementary and alternative medicine: strong preferences for or against the compared therapies will prevent patients to consent to randomisation. In these circumstances a number of alternative designs have been proposed, based on the combination of preference and randomisation, but some of them suffer from severe methodological problems. Others are internally valid but unfeasible in practice and difficult to interpret. Thus, in case of strong patient preferences, we suggest to conduct non-randomised trials but to give special interest to advanced statistical methods (e.g. structural equation models) which must replace simple two-group comparisons.

Controlled Clinical Trials as Topic↗

PubMedDate not supplied

Benchmarking outcome in ICU.

There are as yet few well developed systems for comparing the quality of care in Irish hospitals with other hospitals either nationally or internationally. The best known are the perinatal mortality rates of the Dublin maternity hospitals. Other examples include mortality rates after cardiac surgery and survival rates after cancer surgery. We describe a comparison of outcomes in an Irish ICU with internationally validated mortality rates for a given severity of illness. The method of stratifying for severity of illness is by use of the APACHE II scoring system. In 2003 the standardised mortality ratio for Beaumont Hospital ICU was 0.87 with a mean APACHE II admission score of 17.5 which compares favourably with similar data produced from UK units.

APACHE↗

PubMed2005

[Evaluating the treatment satisfaction of vardenafil in men with erectile dysfunction and female partners by the Treatment Satisfaction Scale].

The Treatment Satisfaction Scale (TSS) has been developed to assess various concepts related to erectile dysfunction (ED) treatment satisfaction in patients and their partners. The self-report questionnaire consists of 4 modules: unmedicated patient, medicated patient, unmedicated partner, and medicated partner modules, measuring a range of sexuality concepts considered important by ED patients and their partners including six domains: "Confidence", "Ease with Erection", "Erectile Function Satisfaction", "Pleasure from Sexual Activity", "Satisfaction with Orgasms", and "Satisfaction with Medication". The TSS is an internationally valid, psychometrically sound instrument to assess patient and partner satisfaction with ED therapy. In a recent double-blind, multicenter, parallel arms, flexible dose clinical trial, the TSS was used to compare patient and partner's satisfaction with vardenafil and placebo therapy. The results demonstrated that vardenafil significantly improved not only erectile function, but also confidence, ease of erection, pleasure, and satisfaction with erectile function, orgasm and medication in men ED and their partners. These attributes are considered to be essential in the acceptance and continued use of PDE5 inhibitor therapy for ED.

Double-Blind Method↗

PubMed2005

Chronic heart failure beyond city limits.

INTRODUCTION: Chronic heart failure (CHF) develops in frail elderly individuals who have suffered an acute or sustained insult to the structural efficiency of the heart due to the presence of underlying heart disease and/or hypertension. It is also more common in individuals with disproportionately high levels of cardiac disease or its risk factors, for example lower socioeconomic status. As such, this epidemic is particularly significant for older people, males and Aboriginal people; groups who comprise a greater proportion of the population in rural and remote Australia. The aim of this study is to determine if the rates of CHF differ between urban and rural Australia. METHOD: CHF prevalence rates derived from well validated international CHF prevalence data were applied to the Australian Bureau of Statistics Census data for 2001 and weighted to reflect the proportion of Aboriginal people in each geographical stratum. RESULTS: Australia wide, the estimated prevalence of CHF was 17.87 per 1000, ranging from 13.98/1000 in the Australian Capital Territory to 29.50/1000 in rural Northern Territory. Overall, CHF was more prevalent in rural and remote regions (19.84/1000) and large urban centres (19.01/1000) than in capital cities (16.94/1000) (p<0.001). High prevalence rates were also noted in the idyllic rural locations favoured by retirees. In Victoria, Western Australia, South Australia and the Australian Capital Territory over 70% of the estimated individual cases were located in capital cities. In New South Wales, Queensland, Tasmania and the Northern Territory the highest proportion of cases occurred outside capital cities. CONCLUSION: The main significance of these findings is that while a majority of heart failure may occur among people living in cities (because that is where most people live), a disproportionate number of cases occur among people living outside these cities (due to age and other socio-demographic risk factors) where services may be fewer and less accessible.

Adult↗

PubMed2005

Ascertainment of meningococcal disease in Europe.

Meningococcal disease surveillance in most countries is based upon a combination of statutory notification systems and laboratory reporting, both of which are recognised to underestimate the true burden of disease. The incidence of meningococcal disease varies throughout Europe, and although there are many reasons for this, it is important to quantify the degree of under-ascertainment in order to validate international comparisons. Here, we review the literature on the ascertainment of meningococcal disease in Europe and the available methods for estimating the degree of under-reporting. We found that the sensitivity of surveillance varies between countries and over time, with estimates ranging from 40% to 96%. We identified five methods suitable for conducting ascertainment studies, from simple comparative studies to more complicated capture-recapture and regression analyses. Studies of ascertainment may be used to identify weaknesses and biases in surveillance data, and facilitate the improvement of these systems. These findings are relevant to the surveillance of other infectious diseases, particularly those with lower mortality and a lower public profile than meningococcal disease, for which ascertainment may be worse.

Europe↗

PubMedDate not supplied

CRTs--cluster randomized trials or "courting real troubles": challenges of running a CRT in rural Gujarat, India.

This paper addresses the logistical challenges of implementing public health interventions in the setting of cluster randomized trials (CRTs), drawing on the experience of carrying out a CRT within a community-based health insurance (CBHI) scheme in rural India. Our CRT is seeking to improve the equity impact--i.e., reduce the differential in claims submission for hospitalization between poor and less poor--of this CBHI in rural areas. Five main challenges are identified and discussed: 1) assigning control clusters, 2) blinding, 3) implementing interventions simultaneously, 4) minimizing leakage, and 5) piggy-backing on a changing scheme. These challenges are not likely to be unique to low-income settings, although the fifth challenge is particularly likely when working with relatively small and resource-constrained programs. While compromises to methodological best-practice may reduce internal validity, they make the intervention more 'real', and potentially more applicable, to other programs and settings. Further, careful documentation of compromises allows them to be considered in the final analysis.

Cluster Analysis↗

PubMed2006

[Systematic evaluation on acupuncture and moxibustion for treatment of dysphagia after stroke].

OBJECTIVE: To assess the therapeutic effect and potential adverse effect of acupuncture in treatment of dysphagia after stroke. METHODS: A systematic review including all the relevant randomized controlled trials (RCTs) or quasi-RCTs of acupuncture and moxibustion for treatment of dysphagia after stroke were performed using the method recommended by the cochrane collaboration. RESULTS: Seven papers including 506 cases met the enrolled criteria. All of the trials were of lower methodological quality. Meta-analysis of enrolled 6 trials showed that the acupuncture group had a better therapeutic effect on dysphagia after stroke than the control group (RR 1.17, 95% CI 1.08, 1.27, Z=3.78, P=0.0002). The mortality and the occurrence of pneumonia were similar between acupuncture and control groups (RR 0.25, 95% CI 0.03, 2.18 and RR 3.02, 95% CI 0.093, 23.10, respectively). The treatment group significantly reduced in time of the thick barium through pharynx examined by videofluorography (WMD -7.23, 95% CI -13.18,-1.28). CONCLUSION: A reliable conclusion can not be drawn from the present data because of the defects in methodological quality, especially no long-term terminal outcome events, although it appears a tendency that acupuncture can improve dysphagia after stroke in short-term with no adverse effect. Therefore, it is necessary to perform more multi central randomized controlled trials in good internal validity and high quality in future.

Acupuncture Therapy↗