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PubMed2001

Effect of cutaneous stimulation on pain reduction in emergency department patients.

CONTEXT: The problem of unrelieved pain in Emergency Department (ED) patients as well as contraindications to analgesics and narcotics due to masking of symptoms during the diagnostic period, presents itself as a unique opportunity for ED nurses to utilize non-pharmacological and non-invasive interventions such as cutaneous stimulation (CS) to relieve pain. OBJECTIVE: To evaluate the effectiveness of a specific protocol of CS, developed by the researchers, in reducing pain levels in ED patients. Another objective was to determine the effect of CS on blood pressure and heart rate. Potential factors that could influence the dependent variables such as age, gender, educational level, location of pain, and site of CS were tested. DESIGN: A one group pre-test post-test experimental design measured variables before and after intervention in all subjects. SAMPLE: After being screened for inclusion, 50 patients (38 adults, 12 children) were admitted to the study and were treated with CS to relieve pain. RESULTS: Following CS, subjects reported significantly reduced pain, and demonstrated reduced heart rate, and blood pressure readings. The location of pain significantly influenced heart rate and diastolic blood pressure but not pain level. The most effective site of CS was contralateral to the pain. Age, gender and educational level had no significant affect. CONCLUSIONS: The results of this study provide empirical evidence that CS effectively reduces pain, heart rate, and blood pressure in ED patients. The intervention of CS has solid utilization potential and could be easily incorporated into standard ED procedure. Further research is needed to identify threats to internal validity especially that of the caring presence of the nurse.

Adolescent↗

PubMed2000

Effect of cutaneous stimulation on pain reduction in emergency department patients.

CONTEXT: The problem of unrelieved pain in Emergency Department (ED) patients as well as contraindications to analgesics and narcotics due to masking of symptoms during the diagnostic period, presents itself as a unique opportunity for ED nurses to utilize non-pharmacological and non-invasive interventions such as cutaneous stimulation (CS) to relieve pain. OBJECTIVE: To evaluate the effectiveness of a specific protocol of CS, developed by the researchers, in reducing pain levels in ED patients. Another objective was to determine the effect of CS on blood pressure and heart rate. Potential factors that could influence the dependent variables such as age, gender, educational level, location of pain, and site of CS were tested. DESIGN: A one group pre-test post-test experimental design measured variables before and after intervention in all subjects. SAMPLE: After being screened for inclusion, 50 patients (38 adults, 12 children) were admitted to the study and were treated with CS to relieve pain. RESULTS: Following CS, subjects reported significantly reduced pain, and demonstrated reduced heart rate, and blood pressure readings. The location of pain significancy influenced heart rate and diastolic blood pressure but not pain level. The most effective site of CS was contralateral to the pain. Age, gender and educational level had no significant affect. CONCLUSIONS: The results of this study provide empirical evidence that CS effectively reduces pain, heart rate, and blood pressure in ED patients. The intervention of CS has solid utilization potential and could be easily incorporated into standard ED procedure. Further research is needed to identify threats to internal validity especially that of the caring presence of the nurse.

Adolescent↗

PubMed1996

Diagnostic tests for temporomandibular disorders: an assessment of the methodologic quality of research reviews.

SUMMARY. The objective of this study was to assess review articles of temporomandibular disorder (TMD) diagnostic tests for methodological quality and to establish the need for a systematic reviewing process. Computerized bibliographic database searches from 1983 to December 1996, information requests from authors, and review of reference lists of all retrieved reports were used to identify relevant reviews. After applying selection criteria, two investigators independently reviewed the articles. Each review article was evaluated independently for methodological quality. Agreement between reviewers was measured using quadratic weighted kappa.Forty-five of 53 review articles met the selection criteria. No review described the search methods, selection criteria, demonstrably avoided selection bias or pooled data of primary studies. Three of 45 articles assessed the internal validity and reliability of the studies included in their review. Major to extensive methodological flaws were noted across all reviews.This critique of methodologic quality in TMD diagnostic review articles supports the need for a systematic reviewing process. Clinicians turning to diagnostic reviews to aid them in synthesizing a large body of literature may wish to apply the described methodologic criteria to separate 'valid' from 'invalid' reviews. Copyright 1996 Harcourt Publishers Ltd.

Journal Article↗

PubMed1998

Quantification of insulin-like growth factor-1 (IGF-1) mRNA: modulation of growth intensity by feeding results in inter- and intra-tissue-specific differences of IGF-1 mRNA expression in steers.

The effect of constant and compensating body growth velocities on IGF-1 mRNA expression was studied in various tissues of growing steers. Twenty-six steers were allocated to three groups in which the average daily gains were kept either constantly high on intensive feeding, low on pasture feeding or were accelerated to compensatory growth after feed restriction. All animals were slaughtered at 570+/-2.6 kg and samples were collected from liver, heart, kidney and from 4 different muscles (m. splenius, m. soleus, m. cutaneus truncii and m. semispinalis capitis), which were selected in order to include maximal differences in fibre composition as well as in growth impetus. IGF-1 mRNA was quantified by a validated internally standardised RT-PCR method. The amount of RNA extracted from the various tissues investigated was constant within each type of tissue and showed no differences between treatment groups. As indicated by a constant ratio between the amount of RNA extracted and the DNA concentrations, there was no effect of the feeding on total transcriptional activity. The order of IGF-1 mRNA abundance per g tissue was liver > > kidney > heart > skeletal muscle. The different feeding regimen resulted in significant differences of IGF-1 mRNA expression rates in all organs showing different patterns between organs. IGF-1 mRNA concentrations showed muscle specific differences and also divergent reactions in response to the differing growth rates. These results support that the liver is the main IGF-1 producing tissue; above that they indicate that skeletal muscle, in particular when taking its absolute mass into account, might considerably contribute to the IGF-1 levels in blood. Our findings demonstrate that IGF-1 mRNA expression is regulated tissue specifically not only between different organs but also within musculature.

Animals↗

PubMed2000

[Effect strength variation in the single group pre-post study design: a critical review].

In Germany, studies in rehabilitation research--in particular evaluation studies and examinations of quality of outcome--have so far mostly been executed according to the uncontrolled one-group pre-post design. Assessment of outcome is usually made by comparing the pre- and post-treatment means of the outcome variables. The pre-post differences are checked, and in case of significance, the results are increasingly presented in form of effect sizes. For this reason, this contribution presents different effect size indices used for the one-group pre-post design--in spite of fundamental doubts which exist in relation to that design due to its limited internal validity. The numerator concerning all effect size indices of the one-group pre-post design is defined as difference between the pre- and post-treatment means, whereas there are different possibilities and recommendations with regard to the denominator and hence the standard deviation that serves as the basis for standardizing the difference of the means. Used above all are standardization oriented towards the standard deviation of the pre-treatment scores, standardization oriented towards the pooled standard deviation of the pre- and post-treatment scores, and standardization oriented towards the standard deviation of the pre-post differences. Two examples are given to demonstrate that the different modes of calculating effect size indices in the one-group pre-post design may lead to very different outcome patterns. Additionally, it is pointed out that effect sizes from the uncontrolled one-group pre-post design generally tend to be higher than effect sizes from studies conducted with control groups. Finally, the pros and cons of the different effect size indices are discussed and recommendations are given.

Case-Control Studies↗

PubMed2003

[Treatment outcome study of the stuttering therapy summer camp 2000 for children and adolescents].

Therapists are generally confronted with the question, to what extent results of randomised clinical trials with their emphasis on internal validity are relevant for practitioners and their unselected patients. Often results from clinical trials are neglected in clinical practice and the "normal" practice remains unstudied. In this study a therapeutic approach for stuttering has been studied under practice conditions, but with a maximum of methodological validity. Beyond the concrete study it is also discussed whether the chosen procedure can be a model for practice studies. Patients from age 9 to 19 participated in a stuttering therapy summer-camp for children and adolescents by the Austria-Self-Aid-Initiative Stuttering. Participants were supposed to learn a more open handling of their stuttering and acquire basics for a fluent speech. The therapy concept includes elements of a fluency shaping and a stuttering modification therapy. The evaluation followed a panel design with two assessments before, one assessment after therapy and one follow-up and three types of measurement: 1. three videotaped speech situations, 2. four questionnaires for the participants and their parents, and 3. Goal Attainment Scalings (GAS). The stuttering frequency shows a reduction from 22.2 to 9.5 % (effect size 1.29). Follow-up results, GAS and all questionnaires also indicate clear improvements. Altogether, the Therapeutic Stuttering Summer-camp was able to reach its aims.

Adolescent↗

PubMed2003

[The Comprehensive Cohort Design as alternative to the randomized controlled trial in rehabilitation research: advantages, disadvantages, and implementation in the SARAH study].

In rehabilitation research new therapies have to be evaluated within randomized trials as the best choice for proving the efficacy. Randomized controlled trials are widely accepted as the definitive method for evaluating the efficacy of new therapies. The random assignment of patients to their treatment ensures the internal validity of the comparison of new treatments with controls. Often patients in a randomized trial only represent a small proportion of the patients who satisfy the inclusion criteria of the trial. This will especially be true in rehabilitation medicine because of strong preferences of the patients for one or the other therapy. An assessment of the external validity of trial results can best be achieved by comparing the study population to the population of patients who met the eligibility criteria but did not consent to randomization. The Comprehensive Cohort Design (CCD) is designed to have the opportunity of recruiting all patients fulfilling these eligibility criteria regardless of their consent to randomisation. Advantages and disadvantages of this study design will be discussed in detail and on the example of the SARAH-study.

Adult↗

PubMed2004

[Quality indicators for ambulatory health education programme for overweight and obese children and adolescents].

BACKGROUND: In Germany, 9 to 12 % of all children between five and seven years of age have been shown to be overweight at school entry; 2.5 to 3.5 % of them are obese. Therapeutic intervention for obese children and adolescents is considered to be indicated especially in cases where an increased body mass index (BMI) is accompanied by a disease the effective treatment of which requires weight loss. Furthermore, the child and its family must be willing to actively change their habits. OBJECTIVE: A multitude of health care providers have begun to offer multidisciplinary group programme for prevention and treatment of obesity to affected individuals and their families. The Medical Service of the Statutory Health Insurance (MDK) has therefore developed a list of quality and assessment criteria for such programme. METHODS: A systematic search for information in international and national publications was performed using standard methodology of evidence-based medicine. Data were extracted and assessed according to pre-defined criteria taking into consideration previously published clinical guidelines and opinions of expert panels. RESULTS: Nearly all available studies were of low internal validity and mostly of poor methodological quality. Therefore, no binding recommendations for the design of health education programme for overweight and obese children and adolescents can be given. Potentially successful intervention should combine the following 4 modules: nutrition, physical activity, change of eating habits, physical activity habits and life style using methods of behavioural therapy, and involvement of parents. Such combinations may have the potential to reduce or stabilise the BMI at least during a defined period of time. In younger children, the beneficial effect will be more pronounced if the parents are actively involved. CONCLUSION: Up to now informative studies have not reliably shown that the effect of ambulatory health education programmes for overweight and obese children and adolescents and their parents may last for more than one or two years. Therefore, a controlled clinical trial determining the long-term effectiveness of such programme is imperative. The decision whether a defined programmes should be included in such a study could be taken on the basis of the quality indicators and assessment criteria described here.

Ambulatory Care↗

PubMed2005

[Prediction of premature pension after stationary rehabilitation due to adipositas--a prognostic model based on routinely collected data of the State Insurance Institution of Baden-Württemberg].

Up to 60 % of the German population can be marked as obese. Due is to its frequency and its associated diseases like cardiovascular disorders and disorders of the musculoskeletal system adipositas is a severe burden on the German health care system. This burden is caused by costs of the disease and costs due to premature pensioning. In this study logistic regression modelling has been performed by means of routinely collected data of patients of the regional statutory pension insurance institute Landesversicherungsanstalt Baden-Württemberg (LVA-BW) rehabilitated due to adipositas (n = 599). The aim was to detect influential variables for the prognosis of premature pensioning (n = 135). The data of the patients were obtained from a research database of the "RehaNet" project which includes data of the standardized discharge report of the Federation of German Pension Insurance Institutes and quality assurance questionnaires of the LVA-BW. Three variables remain in the model after a step-down procedure for modelling by logistic regression. The selected variables are age (in years), the physician's statement about the patients limitations of movement after rehabilitation (yes/no) and about the patients ability to work in future (more/less than half-day). After internal validation of the model by bootstrap methods the model achieves a sensitivity of 73 %, a specificity of 87 %, a positive and a negative predictive value of 57 and 93 % respectively. The area under the curve (AUC) of the ROC analysis is 0.87, so the model achieves a good prognostic value. Thus, this model is a valuable test for the exclusion of possible premature pension while or after rehabilitation due to adipositas. It was found that the situation of "no premature pensioning" of patients rehabilitated due to adipositas can be predicted quite accurately with little information (three variables). This reveals a perspective for further research in the possibility of an early, risk-adapted and individualised intervention after stationary rehabilitation for adipositas to keep employment.

Databases, Factual↗

PubMed1994

Multidimensional assessment of acute and long-term effects in antidepressant drug trials.

Contrasting the findings from pharmacoepidemiological studies with the status of registration of new compounds and the legal process of reviewing the old compounds indicates a crisis of the preclinical and clinical investigations of "antidepressants". Within the last two decades, the development of more and more formalized guidelines and regulations for the performance of clinical drug trials could be observed. Certainly, this has resulted into an improved internal validity of the findings. On the other hand, there appears to be a broad consensus among practising psychiatrists that published findings of clinical trials often do not concur with the experiences of psychiatric practice indicating unsatisfactory external validity. With regard to the aim of optimizing the antidepressant therapy and to lower the costs for mental health care, it appears to be of particular importance to test the real effectiveness of an "antidepressant" as close as possible to its use in practice. (To avoid misunderstandings: This does not mean to ask for more so-called "naturalistic" study designs!) It is self-evident that also in the future controlled studies, particularly vs. placebo, cannot be dispensed with. However, more promising for a relevant assessment of old and new substances would be the use and development of suitable mathematical procedures, which might imply re-evaluations and re-classifications of already published findings; furthermore, it seems essential also to integrate the existing experiences of psychiatrists in hospitals and in private practice.(ABSTRACT TRUNCATED AT 250 WORDS)

Antidepressive Agents↗

PubMed1986

Contribution to the search for vigilance-indicative EEG variables. Results of a controlled, double-blind study with pyritinol in elderly patients with symptoms of mental dysfunction.

We used a clinical pharmacological model to test pyritinol versus placebo in patients with mental deficiency and a clinical diagnosis of beginning chronic brain syndrome. Following a two weeks' washout phase, 50 patients were randomly allocated to two treatment groups of 25 patients each, receiving either 200 mg pyritinol three times daily, or placebo under double-blind conditions. The treatment period lasted 8 weeks. To be included in the study, patients had to have at least 50% subvigil phases in the 15-min EEG resting recording. We define such behaviour as a neurophysiological disturbance of vigilance. Scores in the Benton test were to be 2 points below the expected value, and/or the NAF score was to be above a standard value attained in an old peoples' home (greater than or equal to 14). We used this clinical pharmacological model for an internal validation of our Vigilance Index (VI). According to our definition, the Vigilance Index should express vigilance in the sense of an optimalization of the neuronal system to enable this system to perform better. The delta F power and the alpha slow-wave index have been considered as vigilance-indicative variables in the EEG. We believe that vigilance can be better expressed by a multidimensional approach, which takes into account all EEG elements that express vigilance, such as the replacement of the occipital basic rhythm (e.g. alpha or beta rhythm) into slow waves, the lowering of the dominant occipital frequency (be it an alpha or beta frequency), the anteriorization of the basic rhythm in the occipital field to the frontal region.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1994

[The incidence and prevalence of malignant diseases. A secondary data analysis of a representative random sample of those with local compulsory medical insurance in Dortmund].

Prevalence and distribution of malignant neoplasms were obtained in 1988 and 1989 from a representative random sample of 5% of insured members of the statutory health insurance company in Dortmund, Germany (7447 persons). Data were gathered from medical certificates the diagnosis being further validated internally by other patient data. The cancer prevalence in the sample was 2.3% (males 1.6%, females 3.0%). The average age of the 174 patients with cancer was 67.5 years, half of them 70 years or over. The most frequent cancer was that of the breast (32.2%), followed by that of the colorectum (14.3%) and the skin (12.5%). Standardized for age and sex the prevalence of cancer for the whole population of the Federal Republic of Germany (excluding the former German Democratic Republic) was calculated as 2.2% (males 1.7%, females 2.5%), i.e. 1.33 million patients. The incidence of cancer for 1989 was 0.54%. Taking into account special methodological considerations, the secondary analysis of data obtained from the described source provides information relevant to the care of patients with cancer and thus makes a valuable contribution to the documentation of medical care provision.

Adult↗

PubMed2000

Intravenous Lorazepam versus dimenhydrinate for treatment of vertigo in the emergency department: a randomized clinical trial.

STUDY OBJECTIVE: To determine whether lorazepam is more effective than dimenhydrinate in relieving the symptom of vertigo in the emergency department setting. METHODS: A prospective, randomized, double-blind trial of intravenous lorazepam versus dimenhydrinate therapy was conducted in the ED of a county-owned, university-affiliated hospital. All adult patients who presented between January 24, 1998, and May 23, 1999, with the symptom of vertigo were eligible for inclusion. The intervention was varying the intravenous treatment between lorazepam, 2 mg, and dimenhydrinate, 50 mg. All patients received intravenous infusion of Ringer's lactate solution at a rate of 100 mL/h. Adequacy of randomization to the 2 treatment groups was assessed by comparing the patients' relevant baseline history, physical examination, and symptoms. The predetermined primary outcome measurement was the patient's sensation of "vertigo with ambulation" 1 and 2 hours after treatment. Secondary outcome measurements included vertigo while lying, sitting, and turning the head, ability to ambulate as judged by the enrolling physician, and sensation of nausea and drowsiness 1 and 2 hours after treatment, and whether the patient was "ready to go home" per patient report or physician assessment 2 hours after treatment. All patient symptoms were reported on 10-point scales. Outcome measurements were compared between the 2 treatment groups with a 2-way repeated-measures analysis of variance, Student's t test, Mann-Whitney U, and chi(2) test as appropriate. RESULTS: Ten patients refused entry into the study, 16 were excluded, and 74 were enrolled, treated, and included in the analysis. One enrolled patient had evidence of vertigo of central origin. The pretreatment values of vertigo with ambulation were strongly correlated with the patient's ability to ambulate (P <.001), suggesting good internal validity. The patients randomly assigned to the lorazepam group were sicker based on their pretreatment symptoms and ability to ambulate, and this may have biased the study results. The patients' symptom of "vertigo with ambulation" decreased 1.5 units more (95% confidence interval [CI] 0 to 3.0) on average on a 10-point scale 2 hours after treatment in the dimenhydrinate group. All other measures of vertigo also decreased more in the dimenhydrinate group, although the differences were not statistically significant. At 2 hours after treatment, the patients' ability to ambulate was better in the dimenhydrinate group (P <.001), and 17% (95% CI -2 to 36) more patients in this group were "ready to go home." Patients in the lorazepam group experienced a 1.8-unit (95% CI 0.2 to 3.4) greater increase in drowsiness 2 hours after treatment. CONCLUSION: Our results suggest that dimenhydrinate was more effective in relieving vertigo and less sedating than lorazepam at the intravenous doses administered in this study. Dimenhydrinate appears to be the preferred medicine for patients who present to the ED with vertigo likely to be of peripheral origin.

Adult↗

PubMed2001

An evaluation of the graphical literacy of Annals of Emergency Medicine.

STUDY OBJECTIVE: To describe the type, quantity, and quality of graphics used to present original research in Annals of Emergency Medicine. METHODS: We performed a blinded, retrospective review of all graphics published in Annals of Emergency Medicine's original research articles from January 1998 through June 1999. We assessed the types of graphics, the use of special features to display detail, the clarity of each graphic, discrepancies within the graphic or between the graphic and text, and the efficiency of data presentation. RESULTS: Forty-six percent (68/147) of original research communications contained at least 1 graphic. Of the 128 graphics in these 68 articles, simple univariate displays predominated (53%). Only one third of graphics displayed by-subject data through the use of one-way plots, scatter plots, or other formats. Graphics generally defined all symbols and abbreviations (99%) and were self-explanatory (88%). Techniques for conveying the richness of a data set were seldom used (11% of all graphics). Forty percent (51/128) of the graphics contained internal contradictions (15%), muddled displays (19%), numeric distortion (5%), nonstandard graphing conventions (7%), and other lapses in design or execution. Inefficiencies of data presentation included internal redundancy (16%), extraneous decoration (10%), and redundancy of graphic data with other text/tables (15%). CONCLUSION: The majority of graphics in Annals of Emergency Medicine, although internally valid, failed to take full advantage of the graphic's potential and often depicted summary data when portrayal of subject-specific data was possible. To help readers fully understand research findings, authors and editors should take care to ensure that graphics efficiently and effectively portray the optimal amount of information.

Bibliometrics↗

PubMed2003

Ergometric score systems after myocardial infarction: prognostic performance of the Duke Treadmill Score, Veterans Administration Medical Center Score, and of a novel score system, GISSI-2 Index, in a cohort of survivors of acute myocardial infarction.

BACKGROUND: The aims of the study were to evaluate the performance of the Duke Treadmill Score (DTS) and the Veteran Affairs Medical Center Score (VAMCS) in predicting 6-month death in GISSI-2 study survivors of acute myocardial infarction treated with thrombolytic agents, and to develop a simple predictive scoring system from the same database. METHODS: Patients of the GISSI-2 study (n = 6251) performed a maximal symptom-limited exercise test 1 month after myocardial infarction. We calculated for each patient the DTS and the VAMCS. Based on the coefficients of a multivariate analysis of our database, we developed a simple predictive scoring system and performed an internal validation. The prognostic value of each scoring system was assessed by multivariate analysis. RESULTS: Six-month mortality rates in the subgroups of each scoring system were as follows: DTS: low risk 0.6%, moderate risk 1.8%, high risk 3.4% (P < or =.0001); VAMCS: low risk 0.6%, moderate risk 1.9%, high risk 4.7% (P < or =.0001); GISSI-2 Index: low risk 0.5%, moderate risk 1.9%, high risk 6.1% (P < or =.0001). The results of multivariate analysis (relative risk [RR] and 95% CI) were as follows: DTS: moderate risk 2.50 (1.47-12.59), high risk 5.13 (3.61-15.55); VAMCS: moderate risk 2.65 (1.53-4.59), high risk 5.97 (3.10-11.49); GISSI-2 Index: moderate risk 3.16 (1.81-5.52), high risk 8.65 (4.36-17.18). CONCLUSIONS: The use of ergometric-derived prognostic score systems in a population of survivors of acute myocardial infarction treated with thrombolytic drugs distinguishes subgroups at different risks of death and allows an appropriate recourse to more costly procedures.

Acute Disease↗

PubMed2000

Co-norming the WAIS-III and WMS-III: Is there a test-order effect on IQ and memory scores?

Test-order effect on the WAIS-III and WMS-III scores was evaluated using the WMS-III standardization sample. Participants completed the standardization editions of the WAIS-III and WMS-III in one session, with the tests administered in roughly counterbalanced order. Repeated measure MANOVA analyses were conducted to determine if there was an overall test-order effect for subtest, index, or IQ scores. No significant test-order effects were found for either the WAIS-III index or IQ scores or for the WMS-III index scores. At the subtest level, the majority of the WAIS-III and WMS-III subtests did not show a significant test-order effect. The exceptions were Digit Span and Digit Symbol-Coding on the WAIS-III and Faces II and Logical Memory II on the WMS-III. Although statistically significant test-order effects were found on these subtests, the effect sizes were small. This study indicates that the test-order effect is not a potential threat to the internal validity of the WAIS-III and WMS-III normative data. The practical implications of the current study are discussed.

Adolescent↗

PubMed2002

Prevalence of household food poverty in South Africa: results from a large, nationally representative survey.

OBJECTIVES: Household food insecurity is a major determinant of undernutrition, yet there is little information on its prevalence in the South African population. This paper assesses household food insecurity in South Africa using a quantitative and objective measure, known as food poverty, and provides prevalence estimates by geographic area and socio-economic condition. DESIGN: Secondary data analysis combining two sources: Statistics South Africa's household-based 1995 Income and Expenditure Survey; and the University of Port Elizabeth's Household Subsistence Level series, a nationally-conducted, market-based survey. SETTING: South Africa. SUBJECTS: A nationally representative sample of the entire country - stratified by race, province, and urban and non-urban areas - consisting of 28 704 households. RESULTS: A household is defined to be in food poverty when monthly food spending is less than the cost of a nutritionally adequate very low-cost diet. The prevalence of food poverty in South Africa in 1995 was 43%. Food poverty rates were highest among households headed by Africans, followed by coloureds, Indians and whites. Higher food poverty rates were found with decreasing income, increasing household size, and among households in rural areas or those headed by females. CONCLUSIONS: The widespread nature of household food insecurity in South Africa is documented here. Prevalence rates by geographic and socio-economic breakdown provide the means for targeting of nutritional interventions and for monitoring progress in this field. The corroboration of these findings with both internal validation measures and external sources suggests that food poverty is a useful, objective measure of household food insecurity.

Adult↗

PubMedDate not supplied

An assessment of occupational noise exposures in four construction trades.

Three hundred thirty-eight noise exposure samples were collected from 133 construction workers employed in 4 construction trades: carpenters, laborers, ironworkers, and operating engineers. Four sites using a variety of construction techniques were sampled at least 12 times on a randomly chosen date over a 22-week period. Up to 10 volunteer workers were sampled for an entire work shift on each sampling day using datalogging noise dosimeters, which recorded both daily time-weighted averages (TWAs) and 1-min averages. Workers also completed a questionnaire throughout the workday detailing the tasks performed and tools used throughout the day. Regression models identified work characteristics associated with elevated exposure levels. Comparisons were made between exposures measured using the Occupational Safety and Health Administration (OSHA) exposure metric and the 1996 draft National Institute for Occupational Safety and Health/International Organization for Standardization (NIOSH/ISO) metric to examine the effects of differing exchange rates and instrument response times on construction noise exposures. The mean OSHA TWA for 338 samples was 82.8 dBA +/- 6.8 dBA, whereas the mean NIOSH/ISO TWA for 174 samples was 89.7 dBA +/- 6.0 dBA. Forty percent of OSHA TWAs exceeded 85 dBA, and 13% exceeded 90 dBA, the OSHA permissible exposure limit. The tasks and tools associated with the highest exposure levels were those involving pneumatically operated tools and heavy equipment. Trade was a poor predictor of noise exposure; construction method, stage of construction, and work tasks and tools used were found to be better exposure predictors. An internal validation substudy indicated excellent agreement between worker self-reporting and researcher observation. These data provide substantial documentation that construction workers in several key trades are frequently exposed to noise levels that have been associated with hearing loss, and demonstrate the need for targeted noise reduction efforts and comprehensive hearing conservation programs in the industry.

Humans↗