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PubMed2000

Understanding physical activity intention in Canadian school children and youth: an application of the theory of planned behavior.

The purpose of this study was to investigate the efficacy of the theory of planned behavior in predicting physical activity intention in a nationwide sample of Canadian children and youth. The study sample consisted of participants from Grades 3, 5, 8, and 11 from schools across Canada. School participation was determined by means of a randomly stratified sample design. Results show that the direct measures of the theory of planned behavior explained 47% of the variability in the measure of physical activity intention. In addition, notable differences in the relative contributions of the predictor variables of attitude, subjective norm, and perceived behavioral control were found across grade and grade-by-gender subgroups. The present study provides evidence that in a population of children and youth the determinants display a pattern of change developmentally.

Adolescent↗
PubMed2006

Important parameters for the manufacture of slow-release matrix pellets with an aqueous dispersion of quaternary poly(meth)acrylates in the rotary fluidized bed.

The manufacture of slow-release matrix pellets with an aqueous dispersion of quaternary poly(meth)acrylates was investigated in the rotary fluidized bed. By considering the moisture content of the fluidized bed to be the key process parameter, it was measured on-line throughout the whole manufacturing process. A specially designed sampling device opened new ways to apply NIR spectrometry in laboratory scale processes. It was shown that reproducibly improved pellet properties can be achieved by reproducing the moisture content of the (rotary) fluidized bed. Moisture plateaus proved to be a suitable way to optimize the sphericity of the pellets. Premoisturizing was found to be a very effective tool to achieve slow-release dissolution of the model drug theophylline.

Acrylic Resins↗
PubMed2006

What is happening during the postnatal visit?

The authors' purpose in this study is to describe attendance, timing, and content of the postnatal visit in three communities in Lebanon. Data are collected with a household survey in three economically disadvantaged suburbs of Beirut, Lebanon. The sample was chosen using probability proportional to size sampling design. About half of the women attended their postnatal visit. Timing of the visit and the services provided varied tremendously. Underutilization and major deficiencies in the quality of postnatal services exist. Raising providers' and women's awareness about the postnatal period and focusing on women's postnatal psychosocial needs can improve the quality of maternity services.

Attitude to Health↗
PubMedDate not supplied

Socio-economic status, standard of living, and neurotic disorder.

Evidence on the association between socio-economic status and the prevalence of neurotic disorder is contradictory. We studied the association between three elements of socio-economic status and the prevalence of neurotic psychiatric disorder in a representative sample of adults aged 16-64 living in private households in the UK. A cross-sectional survey of 10,108 adults aged 16-65 resident in private households in the UK was selected by a multi-stage, clustered, random-sampling design. Neurotic disorders were defined using a standardised interview, the revised clinical interview schedule (CIS-R). Data for 9570 people were available for this study. We used housing tenure and access to cars as measures of standard of living; both were associated with the prevalence of neurotic disorder even after adjustment for other socio-economic and demographic variables, including the Registrar General's Social Class and educational attainment. Those people with no access to a car had an odds ratio for neurotic disorder of 1.4 (95% CI 1.1-1.7), compared with those who had access to two or more cars. People who rented their homes were also at increased risk (1.3 [1.1-1.5]). We estimated that about 10% of the neurotic disorder in the UK could be attributed to the increased prevalence of those without cars who rented their homes. There was a complex interaction between the Registrar General's Social Class and sex, and there was no independent association with educational attainment. There is an independent association between low standard of living and the prevalence of neurotic psychiatric disorder. The UK has experienced one of the largest increases in income inequality within western market economies over the past 20 years, and this inequality may have had adverse consequences for the mental health of the population.

Adolescent↗
PubMed2004

A controlled study of comparative efficacy of oral retinoids and topical betamethasone/salicylic acid for chronic hyperkeratotic palmoplantar dermatitis.

BACKGROUND: Chronic hyperkeratotic dermatitis of the palms and soles represents a severe multi-etiological problem, too often faced with ineffective or tedious topical remedies. METHODS: A single-blind, matched-sample design investigation was carried out of 42 patients with chronic hyperkeratotic palmoplantar dermatitis, who were administered acitretin 25-50 mg/day for 1 month, which was controlled versus a conventional topical treatment (betamethasone/salicylic acid ointment). Therapeutic improvement was expressed with the reduction of severity score (expressed on a 0-10 scale). RESULTS: Acitretin was significantly better than the conventional treatment after 30 days (two sided p<0.0001). Moreover, improvement significantly persisted 5 months after suspension of acitretin (p<0.0001), while this was not the case after suspension of the control treatment (p=0.3019). Lesions improved more rapidly with acitretin than with the control treatment (p<0.0002). Some cases of loss of sensitization in patch-test-positive patients were observed. Side effects were minimal or absent, and patients expressed overtly their preference for acitretin treatment. CONCLUSION: After evaluating the former literature, the risks and the benefits, as well as the overt superiority of retinoid treatment, the authors conclude that acitretin should be considered a first choice treatment for this fastidious condition.

Acitretin↗
PubMed2006

A study of Legionella pneumophilia in Tianjin, China.

Legionella is a bacterium identified as the causative agent of Legionnaires' disease commonly found in water and soil in natural environments and human habitats. While most studies are focused on cooling tower water as the source of infection, few studies have compared Legionella from cooling-tower water and water in man-made environments. This cross-sectional study with a randomized cluster sampling design aims to provide information on Legionella found in cooling-tower water and water in man-made environments. Legionella was identified using a dual analytical approach: the serological and the 16SrRNA semi-nest PCR methods. Nine different types of Legionella were identified with the Lp7 type detected in China for the first time. Results indicated slight but insignificantly increased odds (OR = 1.64, 95%CI = 0.54-4.98) of Legionella detection in cooling tower water as compared to water obtained from fountains and parks, suggesting that the mechanism of exposure plays an important role in the causal pathway of outbreaks of Legionnaires' disease.

China↗
PubMed2004

Viable methods for evaluation of community-based rehabilitation programmes.

PURPOSE: The purpose of this article is to discuss some viable and practically feasible methods for evaluation of community-based rehabilitation (CBR) programmes in developing country settings. METHOD: Based on review of literature the role of qualitative approaches for evaluation of CBR programmes are analysed. RESULTS: Aspects of the qualitative paradigm are discussed. The specific qualitative methods of case studies, focus groups, nominal groups, participatory techniques, content analysis, and key informant interviews are deliberated. CONCLUSIONS: Viable alternatives to the qualitative paradigm offer promise in evaluation of CBR programmes. Issues in qualitative designing, sampling, data collection, analysis, and interpretation are discussed. The classical, quantitative paradigm needs to be complemented with viable qualitative methods for evaluation of CBR programmes.

Community Health Services↗
PubMed2005

Memory processing and the glucose facilitation effect: the effects of stimulus difficulty and memory load.

Previous research has consistently found enhancement of memory after the ingestion of a glucose containing drink. The aims of the present study were to specify more precisely the nature of this facilitation by examining the cognitive demand hypothesis. This hypothesis predicts greater glucose induced facilitation on tasks that require significant mental effort. In two experiments, both employing an unrelated sample design, participants consumed either 25 g of glucose or a control solution. In experiment 1, participants first studied low and high imagery word-pairs and memory was assessed 1-, 7- and 14-days later by cued recall. Overall, glucose enhanced both encoding and consolidation processes only for the more difficult low imagery pairs. In experiment 2, the degree of mental effort in a verbal memory task was manipulated in two ways: (1) by varying the phonological similarity of the words; and (2) by varying the length of word lists. Glucose was found to enhance memory only for longer word lists. These data are consistent with the idea that glucose is especially effective in demanding memory tasks, but place some limits on the forms of difficulty that are susceptible to enhancement.

Adolescent↗
PubMed1998

The conditional binomial test revisited for clinical trials.

McNemar's test is used to test the hypothesis that one treatment is better than another in a matched-pair design for binary outcomes. The conditional binomial test in such a matched-pair design is the exact McNemar test. However, in many clinical trials, one wants to establish equivalency between two treatments. We discuss how to use a conditional binomial test to establish equivalency between two treatments in a matched-pair design. Sample size and power determination for each conditional binomial test are calculated. Some statistical properties of the tests are analyzed through Monte Carlo simulation.

Binomial Distribution↗
PubMed2003

Shoulder EMG during depression raise in men with spinal cord injury: the influence of lesion level.

BACKGROUND & OBJECTIVE: The depression-style raise maneuver is commonly performed by persons with spinal cord injury (SCI) to relieve skin pressures and avoid skin ulceration. The demands of this critical activity, however, are not fully documented for individuals with higher spinal cord lesions. The purpose of this investigation was to determine the influence of SCI lesion level on shoulder muscle activity during a depression raise maneuver. EXPERIMENTAL DESIGN: Sample of convenience, group comparison. METHODS: Fine-wire intramuscular electrodes recorded electromyographic (EMG) activity from 12 shoulder muscles in 57 men with SCI while they performed depression raises (C6 tetraplegia, n = 10; C7 tetraplegia, n = 18; high paraplegia, n = 16; low paraplegia, n = 13). EMG intensity was normalized to a manual muscle test (MMT) effort. RESULTS: For persons with paraplegia and C7 tetraplegia, dominant EMG activity was recorded from latissimus dorsi, sternal pectoralis major, and triceps muscles (31%-69% MMT). Tetraplegic groups had significantly greater anterior deltoid activity (C6 = 53%, C7 = 22% MMT) than that recorded in paraplegic groups (high paraplegia = 10%, low paraplegia = 3% MMT). Participants with tetraplegia also had increased infraspinatus activity (C6 = 50%, C7 = 32% MMT) compared with participants with low paraplegia (7% MMT). All other muscles had low or very low EMG activity during the depression raise. CONCLUSIONS: Persons with tetraplegia lack normal strength of the primary muscles used by participants with paraplegia for the depression raise (ie, latissimus dorsi, sternal pectoralis major, and triceps muscles). Although increased anterior deltoid activation assisted with elbow extension, it potentially contributes to glenohumeral joint impingement. Alternate methods of pressure relief should be considered for persons with tetraplegia.

Adult↗
PubMed2005

Test review: Delis-Kaplan executive function system.

The Delis-Kaplan Executive Function System (D-KEFS; Delis, Kaplan, & Kramer, 2001) represents the first set of executive tests co-normed on a large and representative national sample designed exclusively for the assessment of executive functions including flexibility of thinking, inhibition, problem solving, planning, impulse control, concept formation, abstract thinking, and creativity. The D-KEFS, composed of nine stand alone tests that can be individually or group administered, provides a standardized assessment of executive functions in children and adults between the ages of 8 and 89. Utilizing a "cognitive-process approach," the D-KEFS tests allow examiners to systematically generate and evaluate relevant clinical hypotheses on executive functioning of a given examinee by comparing and contrasting performance on multiple testing conditions and using contrast measure scores and error analyses. A review of the administration, scoring and interpretation, test construction, standardization, and technical adequacy indicate that the D-KEFS holds much promise not only as a clinical instrument, but also as a research tool for increasing knowledge of the frontal-lobe functions.

Humans↗
PubMed2000

Drug use among welfare recipients in the United States.

This study examined the prevalence of drug use in a nationally representative sample of 1989 recipients and 6840 nonrecipients of four welfare programs. Data from the 1995 National Household Survey on Drug Abuse (NHSDA) were analyzed using the conditional form of multiple logistic regression with matching of respondents on neighborhood of residence. Weighted proportions and variances accounting for the complex sample design of the NHSDA survey were estimated using the Taylor series linearization method. The results indicate that drug use is 50% more common in households with welfare recipients than in nonwelfare households. Programs making welfare eligibility contingent on the recipient working toward a drug-free lifestyle are worth examining, although a vigilant eye must be kept on the potential unintended consequences.

Eligibility Determination↗
PubMed2000

Linear mixed-effect multivariate adaptive regression splines applied to nonlinear pharmacokinetics data.

In a frequently performed pharmacokinetics study, different subjects are given different doses of a drug. After each dose is given, drug concentrations are observed according to the same sampling design. The goal of the experiment is to obtain a representation for the pharmacokinetics of the drug, and to determine if drug concentrations observed at different times after a dose are linear in respect to dose. The goal of this paper is to obtain a representation for concentration as a function of time and dose, which (a) makes no assumptions on the underlying pharmacokinetics of the drug; (b) takes into account the repeated measure structure of the data; and (c) detects nonlinearities in respect to dose. To address (a) we use a multivariate adaptive regression splines representation (MARS), which we recast into a linear mixed-effects model, addressing (b). To detect nonlinearity we describe a general algorithm that obtains nested (mixed-effect) MARS representations. In the pharmacokinetics application, the algorithm obtains representations containing time, and time and dose, respectively, with the property that the bases functions of the first representation are a subset of the second. Standard statistical model selection criteria are used to select representations linear or nonlinear in respect to dose. The method can be applied to a variety of pharmacokinetics (and pharmacodynamic) preclinical and phase I-III trials. Examples of applications of the methodology to real and simulated data are reported.

Algorithms↗
PubMed1999

An extreme-sib-pair genome scan for genes regulating blood pressure.

Hypertension, a risk factor for many cardiovascular, cerebrovascular, and renal diseases, affects one in four Americans, at an annual cost of>$30 billion. Although genetic mutations have been identified in rare forms of hypertension, including Liddle syndrome and glucocorticoid-remediable aldosteronism, the abundance of plausible candidate genes and potential environmental risk factors has complicated the genetic dissection of more prevalent essential hypertension. To search systematically for chromosomal regions containing genes that regulate blood pressure, we scanned the entire autosomal genome by using 367 polymorphic markers. Our study population, selected from a blood-pressure screen of >200,000 Chinese adults, comprises rare but highly efficient extreme sib pairs (207 discordant, 258 high concordant, and 99 low concordant) and all but a single parent of these sibs. By virtue of the sampling design, the number of sib pairs, and the availability of genotyped parents, this study represents one of the most powerful of its kind. Although no regions achieved a 5% genomewide significance level, maximum LOD-score values were >2.0 (unadjusted P<.001) for regions containing five markers (D3S2387, D11S2019, D15S657, D16S3396, and D17S1303), in our primary analysis. Other promising regions identified through secondary analyses include loci near D4S3248, D7S2195, D10S1423, D20S470, D20S482, D21S2052, PAH, and AGT.

Adolescent↗
PubMed2005

The global status of resistance to antiretroviral drugs.

Since 1989, the emergence of resistant human immunodeficiency virus mutants has been documented for any new antiretroviral agent introduced in the clinical setting; it is a major cause of failure of antiretroviral therapy that may ultimately compromise the antiretroviral's efficacy in the general population. In most cases, resistance is due to poor adherence by the patient and/or to low potency of the therapeutic regimen. Resistance is called "primary" if detected in treatment-naive persons and is called "acquired" when it develops in treatment-experienced persons. This latter population represents potential transmitters of resistant viruses to newly infected persons. Data about the actual prevalence of resistance are derived from studies that differ in design, sample size, geographic area, and definitions. For this reason, a limited number of surveillance programs have been established in the past, both in countries where highly active antiretroviral therapy is widely accessible and in geographic areas where it is being introduced.

Acquired Immunodeficiency Syndrome↗
PubMed2001

Potential use of tea extract as a complementary mouthwash: comparative evaluation of two commercial samples.

OBJECTIVE: To evaluate the potential of using tea extracts as complementary mouthwash and to test the comparative efficacy of two commercial samples. DESIGN: A randomized controlled trial with 30 healthy human volunteers was carried out. The subjects were randomly assigned to 5 groups of 6 subjects per group. The ability of Ndu tea (from Cameroon) and Lipton tea (from Nigeria) to reduce colony forming units (CFU) in the liquid expectorated after 60 seconds of gargling from the mouth of the volunteers at 5 and 60 minutes were evaluated. These were compared to the values obtained from bank water and Minty Brett (thymol 0.047%), a standard antiseptic. SETTING: University of Nigeria, Nsukka, Enugu State, Nigeria. SUBJECTS: Thirty healthy human volunteers (18 males and 12 females, between 22-30 years of age) who met the eligibility requirement of being nonsmokers and not taking any other antimicrobial agent were selected for the study. RESULT: Relative to the bank water, the results indicated that the hot water extract of both teas significantly (p < 0.05) reduced CFU per milliliter in the liquid expectorated after gargling at both 5 and 60 minutes. Minty Brett showed higher activity than both tea extracts; however, unlike Minty Brett both extracts still reduced the CFU per milliliter at time 60 minutes (an indication of longer duration of activity). The combination of the tea extracts with sodium lauryl sulfate (1.2% w/v), a surfactant and emulsifier, significantly increased the antimicrobial activity relative to each tea alone. Comparatively, the activity of Ndu tea was found to be slightly higher than that of Lipton tea but this was not significant (p < 0.05). CONCLUSION: Lipton and Ndu tea extracts potently reduced the CFU per milliliter. This activity was potentiated by sodium lauryl sulfate. Although Minty Brett had more potent antimicrobial activity, both tea extracts have longer duration of activity. The results indicate the potential usefulness of tea extracts as a complementary mouthwash.

Adult↗
PubMed2002

Does mindfulness meditation contribute to health? Outcome evaluation of a German sample.

OBJECTIVES: This exploratory study is the first systematic outcome evaluation to examine the effects of an 8-week meditation-based program in mindfulness in a German sample. DESIGN: Twenty-one (21) participants with chronic physical, psychologic, or psychosomatic illnesses were examined in a longitudinal pretest and post-treatment design with a 3-month follow-up. OUTCOME MEASURES: Both quantitative and qualitative data were gathered. Emotional and general physical well-being, sense of coherence, overall psychologic distress, and satisfaction with life were measured with standardized instruments. RESULTS: Overall, the interventions led to high levels of adherence to the meditation practice and satisfaction with the benefits of the course, as well as effective and lasting reductions of symptoms (especially in psychologic distress, well-being, and quality of life). Changes were of moderate-to-large effect sizes. Positive complementary effects with psychotherapy were also found. CONCLUSIONS: These findings warrant controlled studies to evaluate the efficacy and cost effectiveness of mindfulness-based stress reduction as an intervention for chronic physical and psychosomatic disorders in Germany.

Adult↗
PubMed1991

Reference data for obesity: 85th and 95th percentiles of body mass index (wt/ht2) and triceps skinfold thickness.

Body mass index (BMI) and triceps skinfold thickness (TSF) are commonly used measures of adiposity in clinical and epidemiologic studies. The 85th and 95th percentiles of BMI and TSF are often used operationally to define obesity and superobesity, respectively. Race-specific and population-based 85th and 95th percentiles of BMI and TSF for people aged 6-74 y were generated from anthropometric data gathered in the National Health and Nutrition Examination Survey 1 (NHANES I). The complex sample design of the survey is reflected in the reference values presented. Racial differences in these extremes of the distribution do not emerge until adulthood. Researchers may choose population-based, race-specific, or age-specific criteria for obesity on the basis of assumptions underlying their specific research questions.

Adolescent↗