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PubMed1996

Predicting cardiorespiratory fitness without exercise testing in epidemiologic studies: a concurrent validity study.

Maximal oxygen consumption (VO2 max) is the criterion measure of cardiorespiratory fitness. However, because it has traditionally been regarded as a costly, labor-intense measure to obtain, VO2 max assessment has seen only limited use in epidemiological studies. Recently, methods for predicting VO2 max have been developed that rely on a combination of self-report variables. The purpose of this study was to determine the relationship of two multivariable equations for estimating VO2 max in a sample of 123 females (M age = 38.8 + 8.4 yrs.). In one equation a seven-item physical activity index was used and in the other equation a single physical activity question was used. The between-formula relationship for predicted VO2 max values was significant (r = 0.80, p < 0.0001). Predicted VO2 max values were also positively related with other indices of physical activity (rs = 0.26 to 0.74). Preliminary results suggest there is a high degree of correlation between the two equations studied, as well as other indices of physical activity. These formulas may be of interest to epidemiologists in situations where direct methods of VO2 max assessment are not feasible.

Adult↗
PubMed1999

Using wound care algorithms: a content validation study.

PURPOSE: Valid and reliable heuristic devices facilitating optimal wound care are lacking. The objectives of this study were to establish content validation data for a set of wound care algorithms, to identify their associated strengths and weaknesses, and to gain insight into the wound care decision-making process. METHODS: Forty-four registered nurse wound care experts were surveyed and interviewed at national and regional educational meetings. Using a cross-sectional study design and an 83-item, 4-point Likert-type scale, this purposive sample was asked to quantify the degree of validity of the algorithms' decisions and components. Participants' comments were tape-recorded, transcribed, and themes were derived. RESULTS: On a scale of 1 to 4, the mean score of the entire instrument was 3.47 (SD +/- 0.87), the instrument's Content Validity Index was 0.86, and the individual Content Validity Index of 34 of 44 participants was > 0.8. Item scores were lower for those related to packing deep wounds (P < .001). No other significant differences were observed. Qualitative data analysis revealed themes of difficulty associated with wound assessment and care issues, that is, the absence of valid and reliable definitions. CONCLUSION: The wound care algorithms studied proved valid. However, the lack of valid and reliable wound assessment and care definitions hinders optimal use of these instruments. Further research documenting their clinical use is warranted. Research-based practice recommendations should direct the development of future valid and reliable algorithms designed to help nurses provide optimal wound care.

Adult↗
PubMedDate not supplied

Determination of semicarbazide in fresh egg and whole egg powder by liquid chromatography/tandem mass spectrometry: interlaboratory validation study.

An interlaboratory validation study was conducted according to harmonized protocols to evaluate the effectiveness of a liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the determination of semicarbazide (SEM) in fresh whole egg and in an industrially processed whole egg powder. The sample was extracted with hydrochloric acid and derivatized with 2-nitrobenzaldehyde, with 1,2-[(15)N2(13)C]SEM as the internal standard. The extract was neutralized and purified on a solid-phase extraction cartridge. SEM was determined by reversed-phase LC with detection by MS/MS. Five fresh egg samples, of which 3 were obtained from hens fed nitrofurazone (NFZ), one was spiked with SEM at 50 microg/kg and one was a blank sample, and 5 industrial whole egg powder samples, of which 3 were spiked with fresh whole egg from hens fed NFZ, one was spiked with SEM at 350 microg/kg, and one was a blank sample, were sent to 15 laboratories in 10 different European countries. Results were obtained from 12 participants. Average recoveries of SEM from the fresh egg and the egg powder samples were 105.3 and 121.3%, respectively. The relative standard deviation for repeatability (RSDr) ranged from 2.9 to 9.3%, and the relative standard deviation for reproducibility (RSDR) ranged from 22.5 to 38.1%. The method showed acceptable within- and between-laboratory precision for both matrixes, as evidenced by the HorRat values, at the target levels for the determination of SEM.

Calibration↗
PubMedDate not supplied

Survey of wound, ostomy and continence (WOC) nurse clinicians on stomal and peristomal complications: a content validation study.

PURPOSE: Validated and reliable stomal and peristomal complication definitions and associated interventions are lacking. Available literature is either narrowly medically focused or only of case study level. The objectives of this study were to establish content validation data for the proposed stomal and peristomal complication definitions and their associated interventions, to obtain the data related to contact with stomal and peristomal complication patients, and to gain insight into the ostomy care process. METHODS: A researcher-designed survey was sent to 2900 expert Wound, Ostomy and Continence nurse clinicians via a national mailing to a representative nonrandomized sample of participants who identified that they included ostomy care in their professional practice. In total, 686 nurses returned the survey, a response rate of 24%. The purposive sample was asked to quantify the degree of validity of the survey's stated stomal and peristomal definitions and interventions. Hand-written qualitative comments of the participants were transcribed, analyzed, and themes were derived. RESULTS: On a scale of 1 to 4, the mean score for all definitions and interventions was 3.64 (SD=0.30). The overall survey's content validity index was .91. Ratings demonstrated high consensus validation on the stomal and peristomal definitions and interventions, with definitions scoring higher. The mean scores and the content validity index results on selected items were slightly lower for interventions, especially stomal interventions. Qualitative analysis of participants' comments about the whole instrument generated 10 themes and associated subthemes related to omitted complications and interventions and general observations about the ostomy care process and the validation research process. CONCLUSION: The proposed stomal and peristomal definitions and interventions were rated as generally valid. Further research documenting validation of participants' comments is necessary. Given the findings, additional complications and interventions not identified in the literature were noted and need to be further scrutinized and researched.

Adult↗
PubMed2001

Dynamic measurements of three-dimensional scapular kinematics: a validation study.

The validation of two noninvasive methods for measuring the dynamic three-dimensional kinematics of the human scapula with a magnetic tracking device is presented. One method consists of simply fixing a sensor directly to the acromion and the other consists of mounting a sensor to an adjustable plastic jig that fits over the scapular spine and acromion. The concurrent validity of both methods was assessed separately by comparison with data collected simultaneously from an invasive approach in which pins were drilled directly into the scapula. The differences between bone and skin based measurements represents an estimation of skin motion artifact. The average motion pattern of each surface method was similar to that measured by the invasive technique, especially below 120 degrees of elevation. These results indicate that with careful consideration, both methods may offer reasonably accurate representations of scapular motion that may be used to study shoulder pathologies and help develop computational models.

Adult↗
PubMed1978

The bogus pipeline as lie detector: two validity studies.

The validity of the bogus pipeline procedure for eliciting truthful responses from subjects in social psychological experiments was tested in two studies. Subjects were illegitimately informed about how to perform well on an experimental test, were tested, and then were asked whether they had possessed this prior information. As compared to subjects responding to pencil-and-paper questions or face-to-face questionning by the experimenter, those in a bogus pipeline condition confessed more often.

Electromyography↗
PubMedDate not supplied

Using in vitro prediction models instead of the rabbit eye irritation test to classify and label new chemicals: a post hoc data analysis of the international EC/HO validation study.

The international validation study on alternative methods to replace the Draize rabbit eye irritation test, funded by the European Commission (EC) and the British Home Office (HO), took place during 1992-1994, and the results were published in 1995. The results of this EC/HO study are analysed by employing discriminant analysis, taking into account the classification of the in vivo data into eye irritation classes A (risk of serious damage to eyes), B (irritating to eyes) and NI (non-irritant). A data set for 59 test items was analysed, together with three subsets: surfactants, water-soluble chemicals, and water-insoluble chemicals. The new statistical methods of feature selection and estimation of the discriminant functions classification error were used. Normal distributed random numbers were added to the mean values of each in vitro endpoint, depending on the observed standard deviations. Thereafter, the reclassification error of the random observations was estimated by applying the fixed function of the mean values. Moreover, the leaving-one-out cross-classification method was applied to this random data set. Subsequently, random data were generated r times (for example, r = 1000) for a feature combination. Eighteen features were investigated in nine in vitro test systems to predict the effects of a chemical in the rabbit eye. 72.5% of the chemicals in the undivided sample were correctly classified when applying the in vitro endpoints lgNRU of the neutral red uptake test and lgBCOPo5 of the bovine opacity and permeability test. The accuracy increased to 80.9% when six in vitro features were used, and the sample was subdivided. The subset of surfactants was correctly classified in more than 90% of cases, which is an excellent performance.

Animal Testing Alternatives↗
PubMedDate not supplied

Determination of semicarbazide in baby food by liquid chromatography/tandem mass spectrometry: interlaboratory validation study.

An interlaboratory validation study funded by the European Commission, Directorate General for Health and Consumer Protection (DG SANCO), was conducted to evaluate the effectiveness of a liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the determination of semicarbazide (SEM) in different types of baby food at a possible future European regulatory limit (10 ng/g). The test portion of the sample was extracted with hydrochloric acid, and the analyte was derivatized with 2-nitrobenzaldehyde, with 1,2-[15N2, 13C] SEM as an internal standard. The extract was neutralized and then purified on a solid-phase extraction cartridge. The SEM was determined by reversed-phase LC with detection by MS/MS. Apple puree, rice pudding, and meat/vegetable meal baby food materials, spiked with SEM at levels of about 3, 10, and 30 ng/g, respectively, were sent to 20 laboratories in 12 different European countries, which submitted results from 17 participants. Recoveries ranged from 88.8 to 106.1%. Based on results for spiked samples (blind pairs at 3 levels), the relative standard deviations for repeatability (RSDr) ranged from 4.2 to 6.9% and the relative standard deviations for reproducibility (RSDR) ranged from 16.6 to 24.3%. The method showed acceptable within- and between-laboratory precision for all 3 matrixes, as evidenced by HorRat values, at the target levels for the determination of SEM.

Benzaldehydes↗
PubMed1988

Nephrotoxicity screening in rats: a validation study.

A validation of our non-invasive screening test for the detection of renal damage (Zbinden et al. 1988) is presented. The test is based on repetitive, quantitative urine analysis in groups of six female Sprague-Dawley rats treated on 5 consecutive days with low doses of test substances. Higher doses were administered in the following weeks until nephrotoxic effects or signs of general toxicity were observed. Thirteen reference substances (hexachloro-1:3-butadiene [HCBD], cisplatin, carboplatin, suramin, chloroform, neomycin, rifampicin, phenacetin, phenylbutazone, methicilline, sodium oxalate, ethylene glycol and furosemide) were used. The percentage of rats reaching the test criteria, i.e., pathologic values defined on the basis of measured control values, was determined. In the controls, the overall percentage of rats reaching or exceeding the test criteria was 4.48%, a value that is close to the expected 5%. Evidence of nephrotoxicity was found with all reference compounds. Elevated excretion of cells and occurrence of cylinders were the most sensitive indicators of renal damage. Hematuria was the most frequent finding. Of the other urine constituents measured the enzyme malate dehydrogenase (MDH) was frequently increased. Water consumption, urine volume, pH and specific gravity were occasionally, and protein, glucose, electrolytes, amino acids and gamma-glutamyl-transpeptidase (GGT) were only rarely changed. It is concluded that the screening which is based on quantitative and repeated urine analysis is a useful procedure to detect nephrotoxic chemicals acting by a variety of mechanisms. The histopathological examination of the kidneys contributed useful information of the nature of the toxic effects, but as a screening tool it is less sensitive than quantitative urine analysis.

Animals↗
PubMed1993

Aspiration in bilateral stroke patients: a validation study.

We validated the predictive accuracy of an "old" regression model in a "new" sample of bilateral stroke patients (N = 38). Abnormal gag reflex and impaired voluntary cough accurately predicted radiographically verified aspiration in both samples. A final model, using both samples, grouped patients into three risk strata: low risk of 14% (cough and gag normal), moderate risk of 46% to 51% (one of two behaviors abnormal); and high risk of 87% (cough and gag abnormal).

Adult↗
PubMedDate not supplied

Predicting NCLEX success with the HESI Exit Exam: fourth annual validity study.

The fourth annual validity study of the Health Education Systems, Inc. (HESI) Exit Exam was designed to examine not only the accuracy of the examination in predicting NCLEX success but also the degree of risk for failure of the licensure examination associated with specific scoring intervals. A descriptive comparative design was used to examine the data provided by schools of nursing regarding students' NCLEX outcomes in the 1999-2000 academic year. As in the 3 previous studies, the examination was found to be a highly accurate predictor of NCLEX success (98.46%). Each scoring interval was significantly different from each of the other scoring intervals ( =.001). In fact, for the combined group of registered nurse and practical nurse students, the percentage of students who failed the NCLEX more than doubled with each successively lower scoring interval. These findings provide the information faculties needed to make evidence-based decisions regarding students' risks for NCLEX failure. Additionally, frequency data were obtained from this survey regarding the use of the examination as a benchmark for progression and remediation, and these findings may also be useful to faculties that are considering establishing such programs.

Benchmarking↗
PubMed2005

Three-dimensional rotational X-ray imaging for spine surgery: a quantitative validation study comparing reconstructed images with corresponding anatomical sections.

STUDY DESIGN: A validation study was done in which reconstructed three-dimensional rotational x-ray images were quantitatively compared with corresponding anatomic sections. OBJECTIVES: To assess the accuracy of reconstructed images acquired on a three-dimensional rotational x-ray imaging device. SUMMARY OF BACKGROUND DATA: Minimally invasive procedures have proven quite successful as alternatives for a multitude of open treatments. An unfavorable property of this type of procedure is a lack of direct vision of the operating area. Three-dimensional rotational x-ray imaging may be able to merge the advantages of computed tomography and fluoroscopy: real-time two-dimensional projections for fast visual feedback and three-dimensional reconstructions for detailed volumetric imaging of complex anatomy. METHODS: Twenty traumatic thoracolumbar burst fractures were created and underwent pedicle screw instrumentation and balloon vertebroplasty. Subsequently, a three-dimensional dataset was obtained, and the midsagittal image was reconstructed. The specimens were sliced, and photographs were obtained. Multiple parameters on the reconstructed images and photographs were measured two times by two observers using a graphical method. The differences and standard deviations were calculated for the corresponding parameters and for the intraobserver data. RESULTS: The mean difference between the corresponding values ranged between -1.1 and 2.1 mm for all parameters. The standard deviation for the differences per parameter ranged between 1.2 and 3.2 mm. The intraobserver differences ranged from -0.8 to 1.4 mm, and the standard deviation varied between 0.4 and 2.4 mm. CONCLUSIONS: The reconstructed midsagittal images were accurate in all measured parameters. The three-dimensional rotational x-ray technique may prove to be valuable for less invasive spine surgery.

Aged↗
PubMedDate not supplied

Selection of test chemicals for the ECVAM international validation study on in vitro embryotoxicity tests. European Centre for the Validation of Alternative Methods.

The European Centre for the Validation of Alternative Methods (ECVAM) has sponsored a large international prevalidation and validation study of three embryotoxicity tests, involving embryonic stem cells, limb bud micromass cultures, and post-implantation whole-embryo cultures. The main objective of the study was to assess the performance of these in vitro tests in discriminating between non-embryotoxic, weakly embryotoxic and strongly embryotoxic compounds. An initial part of the study was to select 20 test substances for the formal validation trial, conducted under blind conditions. A database of in vivo and in vitro developmental toxicity test results was complied on 310 chemicals that had been used in previous validation studies, or suggested for such use, or that had good quality "segment II"-type in vivo data, or for which there were human data. From this database, a shortlist of about 30 candidates was constructed. Because the ECVAM study would not include metabolic activation, chemicals known to require activation for their developmental effects were excluded as candidates, although some known stable metabolites were included. Attempts were made: to include substances of diverse mechanism; to avoid overemphasis on pharmaceuticals; to avoid biologically inert substances as non-embryotoxicants; and to make the list different from those used previously. The candidates were of three categories: Class 3, strongly embryotoxic, was defined as developmentally toxic in all species tested, inducing multiple developmental effects, and with a high A/D ratio. Class 1, non-embryotoxic, was defined as not developmentally toxic at maternally toxic exposures, but which may show some minor embryo/fetal toxicity, which cannot be separated from maternal toxicity. Class 2, weakly embryotoxic, were chemicals of intermediate activity. From this candidate list, chemicals of known receptor (androgen, oestrogen, glucocorticoid, aryl hydrocarbon) mechanisms were excluded, on the basis that simple tests for such activity are already available. In addition, chemicals not freely available were excluded, and an emphasis on human data was applied. The final list of 20 chemicals was: Class 3--6-aminonicotinamide, 5-bromo- 2'-deoxyuridine, hydroxyurea, methylmercury chloride, methotrexate, all-trans-retinoic acid; Class 2--boric acid, dimethadione, lithium chloride, methoxyacetic acid, valproic acid (VPA), 2-propyl-4-pentynoic acid (4-yn-VPA), salicylic acid sodium salt; and Class 1--acrylamide, D-(+)-camphor, dimethyl phthalate, diphenhydramine hydrochloride, 2-ethyl-4- methylpentanoic acid (isobutyl-ethyl-VPA), Penicillin G sodium salt, saccharin sodium hydrate.

Animal Testing Alternatives↗
PubMed2004

Accuracy of dietary recall using the USDA five-step multiple-pass method in men: an observational validation study.

OBJECTIVE: This observational validation study was conducted under controlled conditions to test the accuracy of dietary recall in normal weight, overweight, and obese men using the USDA five-step multiple-pass method for dietary recall. DESIGN: Cross-sectional analysis of actual and recalled intake of food during 1 day. SUBJECTS/SETTING: Forty-two men ranging in age from 21 to 65 years and in body mass index from 21 to 39 kg/m(2) who lived in the metropolitan Washington DC area were studied. INTERVENTION: The subjects selected and consumed all meals and snacks, for 1 day, from a wide variety of foods provided at a human study facility. MAIN OUTCOME MEASURES: Actual and recalled energy, protein, carbohydrate, and fat intakes were determined by direct observation and by a 24-hour dietary recall, respectively. Dietary recall was determined via telephone administration of the USDA five-step multiple-pass method the following day. STATISTICAL ANALYSES PERFORMED: Analysis of variance and covariance tested the overall accuracy of recall and the effect of body mass index on dietary recall. Bland-Altman plots were used to assess bias in recall of food intake. RESULTS: In this population of men, there were no significant differences between actual and recalled intakes of energy (3,294+/-111 and 3,541+/-124 kcal/day), protein (117+/-5 and 126+/-5 g/day), carbohydrate (414+/-16 and 449+/-16 g/day), or fat (136+/-7 and 146+/-8 g/day), respectively. Accuracy of recall was not related to body mass index in that the obese men recalled food intake as accurately as the nonobese men. The energy intake of these men was significantly correlated (r=0.57, P<.05) with their estimated energy requirements. Significant interindividual variation in accuracy of recall was found. CONCLUSIONS: Under controlled conditions, the USDA five-step multiple-pass method can accurately assess intakes of energy, protein, carbohydrate, and fat in a population of men regardless of their body mass index. Researchers and clinical dietitians need to continue to examine factors that influence underreporting and overreporting of food intake by the multiple-pass 24-hour recall method.

Adult↗
PubMed1990

A modification of the microplate method for reverse ABO typing of bloodstains and additional validation studies.

The results of additional validation studies of a sensitive microplate hemagglutination assay for ABO reverse grouping of bloodstains are presented. The results of the validation study demonstrate the reliability of the microplate assay for use in routine serological casework. Based on these studies, the microplate assay has now replaced the Lattes crust test for ABO reverse grouping of bloodstains in the FBI Laboratory.

ABO Blood-Group System↗
PubMed1996

MCMI-III diagnostic validity: bad test or bad validity study.

Operating characteristics describe the validity of tests that attempt to dichotomously predict a diagnosis. These statistics are not fully published in the Millon Clinical Multiaxial Inventory-III Manual (MCMI-III manual; Millon, 1994). When calculated from available statistics, the positive predictive powers of the MCMI-III scales are poor both in absolute terms and relative to the MCMI-II (Millon, 1987). There were a number of problems, however, with the initial MCMI-III validity study both inherently and in execution. Although it is doubtful that the MCMI-III is weaker than the MCMI-II, a new validity study is needed.

Diagnosis, Differential↗
PubMed2004

Results of the Leeds assessment of neuropathic symptoms and signs pain scale in Turkey: a validation study.

UNLABELLED: Classification of pain and identification of the specific pain mechanisms through utilization of clinical data are helpful to the physician in choosing the appropriate treatment model. For discrimination between different pain types, various tests could be used. The Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) Pain Scale is a scale based on the analysis of data obtained during bedside examination. The LANSS Pain Scale, as first used by Bennett, is a very useful tool that provides immediate information in the clinical setting and helps distinguish nociceptive pain from neuropathic pain. In this study we targeted validation of the LANSS Pain Scale in the Turkish population. A total of 104 patients who consulted the Algology Department of Istanbul Faculty of Medicine Outpatient Clinic were enrolled in our validation study. The sensitivity and specificity of the scale were found to be 89.9% and 94.2%, respectively. These results suggest a high validity level for the Turkish version of the LANSS Pain Scale. We believe that this scale is a useful tool for the differential diagnosis of neuropathic pain and can be used in future pharmacologic studies. PERSPECTIVE: Any measures that aid in differentiating neuropathic pain from nociceptive pain would facilitate effective management of pain. In daily practice the simplicity of the classification method is important. The present study suggests that Turkish version of LANSS can be used for the discrimination between neuropathic and nociceptive types of pain.

Adolescent↗