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PubMed2004

Recruiting small manufacturing worksites that employ multiethnic, low-wage workforces into a cancer prevention research trial.

INTRODUCTION: Worksites, including those that employ multiethnic, low-wage workforces, represent a strategic venue for reaching populations at risk for developing cancer. METHODS: We surveyed 197 small manufacturing worksites prior to an effort to recruit their workforces into a randomized clinical trial designed to test the effectiveness of a cancer prevention intervention among multiethnic, low-wage manufacturing workers. This paper assesses the external validity of the trial based on three factors: the percentage of potential trial sites excluded from consideration, the percentage of eligible worksites that adopted the trial, and worksite characteristics associated with adoption. RESULTS: We found no statistically significant differences between worksites that adopted the trial and worksites that declined the trial with regard to employee demographics, anticipated changes in workforce size, and perceived importance and history of offering health promotion and occupational health and safety activities. CONCLUSION: Small manufacturing worksites present a viable venue for reaching multiethnic, low-wage populations with cancer prevention programs, although program adoption rates may be low in this sector. Worksites that adopted the trial are likely to represent worksites deemed eligible for the trial.

Biomedical Research↗
PubMed2004

Evaluation of an electronic general-practitioner-based syndromic surveillance system--Auckland, New Zealand, 2000-2001.

INTRODUCTION: During 2000 and 2001, Auckland Regional Public Health Service piloted a general-practitioner-based syndromic surveillance system (GPSURV). OBJECTIVES: The pilot evaluated data capture, the method used to distinguish initial from follow-up visits, the definition of denominators, and the external validity of measured influenza-like illness trends. METHODS: GPSURV monitored three acute infectious-disease syndromes: gastroenteritis, influenza-like illness, and skin and subcutaneous tissue infection. Standardized terms were used to describe the syndromes. Data were uploaded daily from clinics and transferred to a database via a secure network after one-way encryption of patient identifiers. Records were matched to allow the distinction of follow-ups from first visits, based on between-visit intervals of </=8 weeks. Denominator populations were based on counts of unique patients treated at participating clinics during the previous 2 years. Record completion was examined by using before-and-after surveys of self-assessed standardized-term recording. Between-visit intervals were counted for matching records and alternative denominators were calculated on the basis of different observation periods. Weekly influenza-like illness rates were compared with rates generated by an alternative system. RESULTS: Physicians' self-reported recording compliance was highest for skin and subcutaneous tissue infection (71%) and lowest for influenza-like illness (48%). Initial visits had 18%-19% greater compliance than follow-up visits. The number of physicians reporting increasing compliance during the pilot was greater than the number reporting decreases for all conditions. Comparison of data with an independent influenza-like illness surveillance system indicated a close agreement between the two data series. CONCLUSIONS: These results indicate that incidence of acute syndromes can be monitored, at least as successfully as a manual system, by using standardized clinical-term data from selected general-practice clinics. The provision of feedback reports appears to have a limited but positive effect on data quality.

Disease Outbreaks↗
PubMed2004

[Prediction of NDF and ADF concentrations with near infrared reflectance spectroscopy (NIRS)].

The NDF (Neutral Detergent Fiber) and ADF (Acid Detergent Fiber) concentrations in maize stalk were analyzed with 147 samples selected from 600 samples of different eco-environments, hybrids and inbred lines, development stages, and various parts of the plants in two years. The technique of near infrared reflectance spectroscopy (NIRS) and partial least square (PLS) regression were used to establish the models. The results showed that the calibration models developed by the spectral data pretreatment of the first derivative + vector normalization, and the first derivative + multivariate scattering correction were the best for NDF and ADF with the same spectral regions (7501.7-5449.8 cm(-1) and 4601.3-4246.5 cm(-1)). All these models yielded coefficients of determination of calibration (R2(cal)) for NDF and ADF that are higher than 0.94, while R2(cv) and R2(val) ranged from 0.92 to 0.96 for cross and external validation. The root mean square error of estimation, root mean square error of cross validation, and root mean square error of prediction (RMSEE, RMSECV and RMSEP) for NDF and ADF ranged from 1.49% to 1.81%. The models can be used to measure various samples in screening and evaluating quality constituents of silage maize.

Calibration↗
PubMed2005

A methodological framework for the conversion of procedure classifications.

OBJECTIVES: During the adaptation of the Australian Refined Diagnosis Related Groups for Germany mapping tables between procedure classifications were needed. The mapping between the German OPS-301 2.0 and the Australian MBS-Extended should transfer the Australian expertise by keeping a well-established terminology system. METHODS: A methodological framework for the development of mapping tables had been developed based on the model for representation of semantics provided by the European Committee of Standardization. Two approaches were used; the concept-based approach from OPS-301 2.0 to MBS-Extended and the class-based approach the other way round. A conversion had to be identified between 23,160 classes of the OPS-301 2.0 and 6,328 classes of the MBS-Extended in two asymmetrical mapping tables. RESULTS: The class-based approach leads to a low number of 6,980 conversions but misses 82.6% of the classes of the OPS-301. Because of domain incongruencies and missing domain completeness of the OPS-301 2.0 for non-operative procedures 15.7% of the MBS-Extended-classes remain without conversion. The concept-based approach leads to a slightly higher mean number of conversions per class of 1.35 in comparison to 1.31 with the class-based approach. But it was possible to find conversions for 99.5% of the OPS-301 2.0-classes. 16.3% of the DRG-relevant classes of the MBS-Extended were missed. CONCLUSIONS: The class-based approach was not useful, because the MBS-Extended is significantly broader than the OPS-301 2.0. An external validation study for the direction OPS-301 2.0 to MBS-Extended revealed a satisfactory quality. The empirical and the reference-based approach are important alternatives to the ones used in this project. There are clear criteria about the appropriate application area for the methodological approaches presented here.

Diagnosis-Related Groups↗
PubMedDate not supplied

Overview of the evidence for clinical interventions in pediatric dentistry.

PURPOSE: The purpose of this report was to describe the quantity of published literature and types of studies supporting the use of 4 pediatric dentistry procedures: (1) ferric sulfate pulpotomy; (2) stainless steel crowns; (3) space maintainers; and (4) atraumatic restorative technique (ART). METHODS: When available, titles and abstracts of reports written in English and published over a 36-year period (1966-2002) concerning these procedures were retrieved from MEDLINE. They were classified using a modified classification scheme that, in addition to the study designs, also considered the 4 dimensions of measuring dental outcomes. RESULTS: The quantity of available literature concerning each dental procedure varied considerably. Even though many reports were published on treatments, only a small proportion of the published literature for each procedure was found to evaluate outcomes, regardless of outcome dimension. Besides outcomes evaluations, studies on techniques, material properties, and review articles comprised a large proportion of the literature. Clinical dimension of outcomes was most commonly studied. Case series and case reports were the most frequently used study designs to report outcomes. CONCLUSIONS: The outcomes-related literature to support some of the commonly performed treatments is limited both in quantity and study types. More reports are needed to develop the evidence base to support the commonly performed procedures in pediatric dental practice. Additional analyses reporting of the literature are also needed to assess internal and external validity of the studies.

Child↗
PubMedDate not supplied

Estimation of mental health care cost units for patients with schizophrenia.

INTRODUCTION: The disease-cost study, based on the study of cohorts of patients through their visits to the mental health system, requires knowledge on the cost of each health care unit. However, lack of standardized procedures limits the external validity of the results obtained. When methodological information regarding the procedures applied is available, it makes it possible to compare the internal validity and to understand the suppositions on which the cost estimations have been made. METHODS: Cost-units for the health care received by a cohort of patients diagnosed of schizophrenia were estimated. The study was performed by a community-based team and at several hospital premises belonging to the Andalusia Health Service. A sensitivity analysis was conducted whenever necessary. RESULTS: Both in inpatients and outpatients care, personnel represents the biggest cost, this proportion being higher within the outpatient care. Among the professional categories the care given by the psychiatrists is the most expensive. Time load is similar for the different categories except for the psychiatrist. CONCLUSIONS: Cost unit estimates are lower than that which has been published internationally and within Spain. However, the findings must be carefully considered due to the influence that the different methodological options may have.

Ambulatory Care↗
PubMed2005

[Predicting the chemical composition of intact kernels in maize hybrids by near infrared reflectance spectroscopy].

Intact-kernel samples of normal maize inbred lines and hybrids were collected from field experiments of three locations. Calibration equations were developed by partial least square regression (PLS) of chemical values of near infrared reflectance spectroscopy (NIRS) data and tested through both cross and external validation. In addition, 40 progenies of F1 and F2 generation not included in calibration and validation sets were verified to further evaluate the reliability of three calibration equations. The authors found the coefficients of correlation (r) of 0.98, 0.93 and 0.97 between NIRS predicted and actual protein, starch and oil content in these materials, respectively. However, the greatest relative errors were 2.7% (protein), 2.46% (starch) and 7% (oil). Thus, the accuracy of prediction could be comparable to chemical methods. The feasibility of developing NIRS equations with samples of inbred lines to determine grain quality of hybrids was also examined. The analysis of principal components of spectrum of the inbred lines and hybrids supported a new theory that plant spectrum properties could be heritable.

Feasibility Studies↗
PubMed2005

Analysis of acrylamide in food: dedicated to Professor Dr. Werner Baltes.

Since the first discovery of the presence of acrylamide in a variety of food products in April 2002, numerous methods have been developed to determine the acrylamide monomer in heat-treated carbohydrate-rich food. These detection methods are mainly MS-based, coupled with a chromatographic step using LC or GC. The Food Chemistry Institute (LCI) of the Association of the German Confectionery Industry (BDSI) therefore established a detection method by means of aqueous extraction plus a cleaning step and LC-MS/MS detection, making great efforts to ensure internal and external validation. Citing potato crisps as an example, we will in the following show how the German manufacturing companies have gone to great pains to reduce acrylamide levels in their products.

Acrylamide↗
PubMed2006

Robustness of a computer-assisted diabetes self-management intervention across patient characteristics, healthcare settings, and intervention staff.

BACKGROUND: A major problem in the dissemination of most interventions found to be efficacious is that they are of limited or unknown generalizability. OBJECTIVE: To document the "robustness," or external validity, of a computer-assisted diabetes self-management program across different patient characteristics, healthcare settings (mixed payer vs health maintenance organization), intervention staff, and outcomes. STUDY DESIGN: A randomized controlled trial evaluating a computer-assisted behavior change program for adult patients with type 2 diabetes mellitus (n = 217) vs a computerized health risk assessment. METHODS: Outcomes were identified using the RE-AIM framework and included program adoption among physicians, reach across patient groups, implementation, and behavioral (fat intake and physical activity) and biological (glycosylated hemoglobin and lipid levels) effectiveness measures. RESULTS: The program achieved 41% patient participation, variable adoption across healthcare settings (76% of health maintenance organization physicians vs 18% of non-health maintenance organization physicians participated), good implementation, and improvement in behavioral outcomes. There were few significant interactions between treatment condition and patient characteristics, type of healthcare setting, or interventionist experience on effectiveness measures. CONCLUSIONS: Patients and physicians were willing to participate in a computer-assisted dietary and physical activity goal-setting intervention, although participation varied by healthcare setting. Interventionists from different backgrounds successfully delivered the intervention, and the results appear robust across various patient and delivery characteristics.

Aged↗
PubMed2006

[Development and use of a quality assessment scale specifically constructed for the assessment of studies that compare hemodialysis modalities].

There are currently many hemodialysis modalities that are believed to be superior to conventional hemodialysis. In order to compare the effectiveness and security of the different hemodialysis techniques a systematic review was carried out. Faced with the fact that the scales available mainly focus on study design and tend to ignore external validity, a quality scale was specifically developed to assess the quality of the studies included in the review. The objective of this article is to introduce the quality assessment scale developed and present the results of its usability and applicability. The following databases were searched in order to identify the studies: MEDLINE, EMBASE, Cochrane, HTA, CRD and others. The articles obtained were selected based on previously established inclusion/exclusion criteria. The scale covers three issues: general aspects of the studies, specific aspects of the studies and patient characteristics. This scale allowed for a more accurate classification of the global quality of the studies and was reproducible. In general, those studies classified as high quality studies received the highest score and those studies classified as low quality studies received the lowest scores. The median value was 5,35 (53,5%). The intraclass correlation coefficient was 0,96. As a conclusion of this work it can be stated that currently available scales have serious limitations for the use in studies that compare different hemodialysis modalities and that the use of a scale specifically constructed for this purpose provides more accurate information on the quality of the evidence which is fundamental to interpret results and generate inferences.

Hemodiafiltration↗
PubMed2006

Prevalence of chronic wounds in Quebec home care: an exploratory study.

Because the prevalence of chronic wounds in Quebec is unknown, researchers conducted a chronic wound prevalence feasibility study in severely ill, elderly, or bedridden home care patients. Questionnaires seeking information about the number of wounds, patient comorbidities, and characteristics of the most severe wound (etiology, location, duration, progress, and treatments) were mailed to the head nurse and home care nurses of 149 local community health centers. Information regarding nurse and general health center needs related to chronic wound prevention and care also was solicited from nurses in 52 health centers. Data were obtained from 488 patients (average age 68.5 years); an overall prevalence rate of 1.4% was determined. Most patients (81%) had one or two wounds and pressure ulcer was the most common etiology (37% of wounds). Wounds had existed for a mean of 26.8 months (range 0 to 180, median 12 months). Most (94%) patients had a family physician but only one third of family physicians were responsible for the wound care provided/prescribed. Lack of time was the most frequently cited reason for not completing the survey. Wound chronicity, severity (44% of pressure ulcers were Stage III), lack of improvement (60% cited no improvement or worsening of ulcer), the absence of protocols and training in some local community service centers, and inappropriate use of therapeutic modalities are important reasons for concern and provide opportunities for improvement. Sample size and the absence of verifiable data limit the external validity of the findings but results indicate that chronic wounds are a common and important concern among home healthcare patients in Quebec. Improvements in data collection and patient protocols of care are needed to facilitate the acquisition of much-needed wound prevalence and outcomes data to help agencies provide optimal patient care.

Activities of Daily Living↗
PubMed2006

To drive or not to drive (after TBI)? A review of the literature and its implications for rehabilitation and future research.

Development of reliable procedures to assess fitness to safe driving after traumatic brain injury (TBI) is a crucial step in rehabilitation. However, prior studies are highly inconsistent in the choice of measures recommended for predicting driving fitness from different pre-driving measures. In the present paper the relevant literature is reviewed with the aim of shedding light on the reasons for these inconsistencies. The discrepant results reflect investigative choices which differ in five aspects: (1) the type of predictors used as pre-driving screening; (2) the type of measures considered as the criterion for the determination of fitness to drive after TBI; (3) the severity of the TBI in the sample of patients studied; (4) the extent of the neural structures damaged by TBI and the overlap of these areas with those involved in driving tasks; (5) the length of the follow-up considered. The strengths and weaknesses of the different methods and measures are discussed with their implications for future research and clinical rehabilitation. Encouraging findings come from recent studies that combined together medical, psychosocial, and personality measures, thereby improving the explanatory power of the predictors used. The use of post-injury driving fitness measures with great ecological and external validity seems equally promising in assessing actual driving in the real world.

Automobile Driving↗
PubMed2006

[Prediction of IVDMD with near infrared reflectance spectroscopy (NIRS) in maize stalk].

The in vitro dry matter digestion (IVDMD) in maize stalk was analyzed with 161 samples selected from 600 samples of different eco-environments, hybrids and inbred lines, development stages, and various parts of the plants in two years. The technique of near infrared reflectance spectroscopy (NIRS) and partial least square regression (PLS) were used to establish the models by comparing several preprocessing procedures and wavelength ranges. The optimal models could be obtained in the range of 6 101. 7-5 773. 8 cm(-1) and 4 601. 3-4 246. 5 cm(-1) by the spectral data preprocessing of the Max-Min normalization. The model is suitable for measuring various sample IVDMD. The determination coefficients of the modes were 0.907 3 and 0.906 6 for cross and external validation, respectively. The root mean square error of prediction was 2.08%, and the coefficient of correlation(r) was 0.956 between NIRS predicted and actual IVDMD in these materials. The results showed that NIRS is a simple effective means for measuring IVDMD in maize stalk. The results are of great value of application in screening and evaluating quality constituents of silage maize.

Animal Feed↗
PubMed2006

A prognostic model for functional outcome in early rheumatoid arthritis.

OBJECTIVE: To construct a prognostic algorithm to predict 5-year functional outcome in rheumatoid arthritis (RA), based on the Health Assessment Questionnaire (HAQ). METHODS: Data from all patients with 5-year followup (n = 985) were used from an inception cohort, the Early Rheumatoid Arthritis Study (ERAS). Possibly relevant prognostic factors considered in the initial stage of the model-building process were standard clinical, radiological, and laboratory features measured at baseline and at 1 year. Multivariate analysis was performed using logistic regression, and the predictive performance of the model was tested using measures of discrimination and calibration. RESULTS: Bootstrap resampling identified 6 variables that consistently predicted severe functional outcome. Functional grade III/IV (odds ratio 6.7) and HAQ at 1 year (odds ratio 2.4) were the most important. Other variables included socioeconomic status, hemoglobin, and radiographic and disease activity scores. Estimates of the regression coefficients and performance were corrected for over-fitting. Reasonably large values for the c-index (0.82) and the Nagelkerke R(2) (0.39) indicate that the set of prognostic factors explains the variation in outcome to a degree that implies good prediction for individual patients. CONCLUSION: The algorithm identifies patients in the first year of RA who are likely to have poor function by 5 years and who could potentially benefit from aggressive drug therapy. A nomogram is produced for simple application of the model in clinical practice. While further external validation is necessary, this model could allow clinicians to target aggressive therapy earlier in a patient's disease course.

Adult↗
PubMed2006

Quercus pollen season dynamics in the Iberian peninsula: response to meteorological parameters and possible consequences of climate change.

The main characteristics of the Quercus pollination season were studied in 14 different localities of the Iberian Peninsula from 1992-2004. Results show that Quercus flowering season has tended to start earlier in recent years, probably due to the increased temperatures in the pre-flowering period, detected at study sites over the second half of the 20th century. A Growing Degree Days forecasting model was used, together with future meteorological data forecast using the Regional Climate Model developed by the Hadley Meteorological Centre, in order to determine the expected advance in the start of Quercus pollination in future years. At each study site, airborne pollen curves presented a similar pattern in all study years, with different peaks over the season attributable in many cases to the presence of several species. High pollen concentrations were recorded, particularly at Mediterranean sites. This study also proposes forecasting models to predict both daily pollen values and annual pollen emission. All models were externally validated using data for 2001 and 2004, with acceptable results. Finally, the impact of the highly-likely climate change on Iberian Quercus pollen concentration values was studied by applying RCM meteorological data for different future years, 2025, 2050, 2075 and 2099. Results indicate that under a doubled CO(2) scenario at the end of the 21st century Quercus pollination season could start on average one month earlier and airborne pollen concentrations will increase by 50 % with respect to current levels, with higher values in Mediterranean inland areas.

Air Pollutants↗
PubMed1992

[Unemployment and ill health--or the other way around?].

In response to a recent article in Nord Med (No 11/91) this paper raises a critique of the reanalysis of two Nordic studies on the effects of unemployment on health: The model based on varying relationships between vocational ability and job requirement does not invalidate earlier findings. However, the interpretation of measurements of health in individual based follow-up studies warrants a discussion, as well as the external validity of their findings. Unemployment has been shown to affect health related behaviour, like consultation rates, referrals, sick leave and disability pension, in well controlled studies. These effects are of importance to the individuals and the health- and social services, regardless of their relation to disease in a biomedical sense.

Adult↗
PubMed1992

[Self assessment of the functional level in a group of psychiatric patients on admission and discharge. Aspects of the reliability of the Sickness Impact Profile].

A comparison was undertaken between a method of personal assessment of the functional level and the health related quality of life, the Sickness Impact Profile (SIP) and a method based on observers, the Nurses' Observation Scale for Inpatient Evaluation, in a little group of mentally ill patients. This revealed good sensitivity as regards the registered effect of treatment and fairly good agreement between the results. SIP has gradually been demonstrated to be a well proved and widely employed method within many medical specialties with both internal and external validity.

Humans↗
PubMed1991

[Emotional status and immunoglobulin A in saliva--review of the literature].

Salivary immunoglobulin A, secreted by the local secretory immune system of the upper respiratory tract, plays an important role in the protection of infections. Psychoneuroimmunological studies postulating influences of mood states on secretion of immunoglobulin A are reviewed and discussed with regard to their internal and external validity. The results on the influence of emotional stress are heterogeneous: Lower, as well as higher, as well as unchanged secretions of salivary immunoglobulin A have been reported. This may be due to insufficient control of intervening variables, to different methodologies and to selection of non-representative subject populations, so that the relationship between emotional stress and secretion of salivary immunoglobulin A remains still under discussion. On the other side, two studies indicate that mental relaxation procedures can lead to increased secretions of salivary immunoglobulin A in comparison to vigilance task, finger touching or no explicit treatment. However, more research is required, especially on the size and duration of the induced effect. Future psychoneuroimmunological research strategies should consider to a greater extend emotion-specific and person-specific aspects, methods used in experimental virology and mediators between mood and salivary immunoglobulin A.

Arousal↗