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PubMed2002

Reliable and valid self-report outcome measures in sexual (dys)function: a systematic review.

This paper examines the published reliability and validity of non-disease specific, self-report measures of sexual function. Relevant papers were found in a search of the Embase electronic bibliographic database, for English language papers (published 1980-99) reporting on the psychometric testing of sexual function questionnaires. Existing published reviews or collections of such instruments were also searched, and the reference lists of all papers obtained were "back-searched" to identify other measures. Included measures were evaluated in a systematic manner using published standards concerning the validity, internal consistency, and reproducibility of health measurement scales and quality of life measures. Twenty-three self-report measures were identified for inclusion in this review. A further 2 measures were identified by reviewers of this paper after the main searches were undertaken. One measure was found not to be exclusively self-report. Eleven (46% of 24 included measures) did not meet minimum published standards for reliability, internal consistency, and validity. However one of these was reliable and valid in the female-version only. Of the 14 reliable and valid measures, or versions thereof (58% of 24), 2 (8% of 24) met "superior" psychometric standards. Many measures were developed for use with patients in sex or marital therapy, and are mainly suitable for administration to people with long-term sex partners. It is sensible to assume that instruments are only reliable and valid in the often specialized populations in which they were developed.

Female↗
PubMed2001

Incremental validity of the Ego Impairment Index: a re-examination of Dawes (1999).

This article examined the incremental validity of the Ego Impairment Index (EII), a Rorschach measure of cognition, perception, and reasoning. R. M. Dawes (1999) borrowed 2 previously published data sets to assess the incremental validity of the EII. Dawes determined that in order for the EII to be considered a valid measure, the overall EII score should "outperform" 2 of the variables that compose the index. Using this approach, Dawes reported that the EII had "deficient" (p = .059) incremental validity. In this study, the incremental validity of the EII was re-examined using 1 of the data sets used by R. M. Dawes (1999). Applying the same strategy as Dawes, the author tested the incremental validity of the EII in predicting positive symptoms of schizophrenia, a more appropriate and clinically relevant criterion measure of impairment. The EII significantly predicted positive symptoms (p < .005) even after the 2 EII variables selected by Dawes and the measure of social competence were 1st entered into the equation. The results suggest that the EII adds meaningful information in the assessment of thought disturbance.

Adult↗
PubMed2004

Development and cross-validation of a prediction equation for estimating resting energy expenditure in healthy African-American and European-American women.

OBJECTIVE: To develop, validate, and cross-validate a formula for predicting resting energy expenditure (REE) in African-American and European-American women. DESIGN: A cross-sectional study of REE in women. Participants were randomly assigned to one of two groups. One group served to develop and validate a new equation for predicting REE while the second was used to cross-validate the prediction equation. The accuracy of the equation was compared to several existing formulae. SETTING: University metabolic laboratory, Memphis, TN, USA. SUBJECTS: Healthy, premenopausal African-American and European-American women between 18 and 39 y of age. The validation sample included 239 women (age: 28.4 y, wt: 70.7 kg, body mass index (BMI): 25.2 kg/m(2), REE: 5840 kJ/day), while the cross-validation sample consisted of 232 women (age: 27.5 y, wt: 70.7 kg, BMI: 25.2 kg/m(2), REE: 5784 kJ/day). RESULTS: The prediction equation derived from the current sample, which included adjustments for ethnicity, was the only formula that demonstrated a high level of accuracy for predicting REE in both African-American and European-American women. The mean difference between REE predicted from the new formula and measured REE was 28 kJ/day (s.d.=668) for European-American women and 142 kJ/day (s.d.=584) for African-American women. CONCLUSIONS: Previous equations for predicting energy needs may not be appropriate for both African-American and European-American women due to ethnic differences in REE. A new equation that makes adjustments in predicted REE based on ethnicity is recommended for determining energy needs in these groups (Predicted REE (kJ/day)=616.93-14.9 (AGE (y))+35.12 (WT (kg))+19.83 (HT (cm))-271.88 (ETHNICITY: 1=African American; 0=European American)). SPONSORSHIP: Support for this study was provided by Grant #HL53261 from the National Heart, Lung, and Blood Institute.

Adolescent↗
PubMed2005

Validity of the detection of wheelchair propulsion as measured with an Activity Monitor in patients with spinal cord injury.

STUDY DESIGN: Validation study. OBJECTIVES: An accelerometry-based Activity Monitor (AM) has proven to be a valid instrument to quantify mobility-related activities (lying, sitting, standing, walking, cycling, general (noncyclic) movement). The aim of this study was to assess whether, additional to other activities, wheelchair propulsion (hand-rim wheelchair propulsion and handbiking) can be validly detected by the AM in patients with spinal cord injury (SCI). SETTING: Rehabilitation center. METHODS: In all, 10 patients with SCI (aged 19-63 years; five patients with poor triceps strength and five patients with good triceps strength) participated. Patients performed a series of representative daily life activities (involving wheelchair propulsion and nonwheelchair propulsion activities), according to a standard protocol, in a seminatural setting. Continuous registrations of signals from body-fixed accelerometers were made and the AM output (after automatic analysis) was compared with visual analysis of simultaneously made video recordings (reference method). Validity scores (agreement, sensitivity, specificity) between the output of the AM and the video analysis were calculated. RESULTS: Agreement, sensitivity and specificity for the detection of wheelchair propulsion were overall 92 (range, 87-96)%, 87 (76-99)% and 92 (85-98)%, respectively. Sensitivity was smaller in patients with poor triceps strength compared to patients with good triceps strength; 81 (76-89)% and 95 (89-99)%, respectively (P<0.01). Mean overestimation in duration of wheelchair propulsion by the AM was 3.9% (P<0.05). CONCLUSION: Besides already validated other activities, wheelchair propulsion (hand-rim wheelchair propulsion and handbiking) can be validly detected by the AM in patients with SCI, both with good and poor triceps strength. Therefore, the AM offers the possibility to obtain objective and detailed information on all major mobility-related activities performed by patients with SCI. SPONSORSHIP: Stichting Rotterdams Kinderrevalidatie Fonds Adriaanstichting.

Acceleration↗
PubMed2001

Validity in action research: a discussion on theoretical and practice issues encountered whilst using observation to collect data.

AIM: The paper contributes to an understanding of validity in action research methodology by examining issues arising from our attempts to describe the role of an observer in an action research study. BACKGROUND: Our experiences in observing patient care in intensive care settings are used to illuminate discussion on the nature of validity in action research. CONTENT: The paper examines the nature of validity in action research methodology before briefly describing a study that included observing intensive care staff providing patient care. Various perspectives on observation as a research method are critically examined. These include observer role, level of participation, use of cover, structure and timing of observation. Validity in action research underpins the discussion in the paper. CONCLUSION: We conclude that it may not always be possible to categorize the role of the observer within existing definitions. It may be better to summarize the actual observer role as a way of illustrating validity so that the reader can judge the validity of the findings from an action research study.

Critical Care↗
PubMedDate not supplied

Reproducibility and clinical and concurrent validity of the MSF-4: a four-item male sexual function questionnaire for patients with benign prostatic hyperplasia.

INTRODUCTION: The MSF-4 (Male Sexual Function 4-item) questionnaire is a condition-specific four-item scale of men's sexuality. We describe two studies that were conducted to assess the reproducibility and validity of the MSF-4 questionnaire. METHODS: Study 1 was a Phase III, multicenter study with a double-blind, parallel group design which was conducted in five countries. The objectives were to check the construct validity and factorial structure of the MSF-4 along with internal consistency reliability and clinical validity. Study 2 was a longitudinal, noncomparative, observational multicenter study to assess the reproducibility and the clinical and concurrent validity of the MSF-4. RESULTS: When exploratory factor analysis was performed with a free number of factors, the variability of the global MSF-4 score was based on a single factor across all countries in Study 1 except Spain. There was a high level of internal consistency reliability (Cronbach's alphas 0.68-0.90) and the MSF-4 was able to significantly discriminate different health states as assessed by the International Prostate Symptom Score (I-PSS) or Quality of Life (QoL) questionnaire. In study 2, there was a significant correlation between the MSF-4 and the International Index of Erectile Function (IIEF) scores (p = .0001 for all items) especially erectile function (correlation coefficient -0.77). The MSF-4 was able to distinguish among patients with differing degrees of benign prostatic hyperplasia (BPH) symptoms as measured by the I-PSS (p = .0001) and between those with and without sexual disorders (p = .0001). CONCLUSION: The MSF-4 is a psychometrically validated questionnaire with good reproducibility and clinical validity, which allows easy and appropriate assessment of male sexual function in the clinical setting.

Aged↗
PubMed2003

Reproducibility and validity of the secondary level School-Based Nutrition Monitoring student questionnaire.

OBJECTIVE: To evaluate the reproducibility and validity of the School-Based Nutrition Monitoring (SBNM) secondary level student questionnaire. DESIGN: Reproducibility was evaluated using a test-retest study design by administering the questionnaire on the same day (morning and afternoon, n=254) and, when appropriate, 9 to 14 days apart (n=259). Validity was assessed by comparing foods selected on the questionnaire with foods reported from a single 24-hour recall covering the same referent period (yesterday) in 209 students. SUBJECTS/SETTING: Eighth grade students in middle schools from central Texas were used: male and female, approximately 75% white, for the reproducibility study, with 15% Hispanic, 6% African American; for the validation study, approximately 38% white, 41% Hispanic, and 17% African American. STATISTICAL ANALYSIS: Spearman rank order correlation, kappa statistic, and percentage agreement were used for both reproducibility and the validation. RESULTS: For the reproducibility study, agreement for questions about food intake "yesterday" were 70% to 98%, with kappa statistics ranging from 0.54 to 0.93 and correlations between 0.66 and 0.97. Questions on recent physical activity had high agreement (66% to 89%) as did "usual" physical activity items, weight loss, and food selection behaviors. Nutrition knowledge items showed relatively weaker reliability: agreements ranged from 47% to 92%, with kappa statistics between 0.30 and 0.56. Attitude questions had weaker agreement (50% to 87%), kappa statistics (0.27 to 0.52), and correlations (0.33 to 0.63). For the validation study, correlation coefficients ranged from 0.32 for breads to 0.68 for milk and beans. Percentage agreement ranged from 38% for breads to 89% for gravy. APPLICATIONS/CONCLUSIONS: Most questions on the SBNM secondary questionnaire were found to have acceptable reproducibility, whereas validation of food choice behaviors showed results similar to or better than other dietary assessment instruments for this age group. This questionnaire is a useful epidemiologic tool for surveillance, assessing broad intervention effects among groups or providing needs assessment data on selected nutrition and physical activity-related constructs.

Adolescent↗
PubMed2004

Reliability and validity of a food-frequency questionnaire for Chinese postmenopausal women.

OBJECTIVES: (1). To determine the reliability and validity of a food-frequency questionnaire (FFQ) for use in epidemiological research in postmenopausal women; and (2). to compare the volume estimation (VE) and weight estimation (WE) method of administration of this questionnaire. DESIGN: An initial list of foods was derived and modified after pre-testing in 22 subjects. Test-retest reliability was assessed in 21 subjects who had repeat administrations of the questionnaire 14 days apart (FFQ1, FFQ2). The validity of the FFQ was assessed by comparing nutrient intakes with those from a 4-day food record. SETTING: Chengdu, People's Republic of China. SUBJECTS: Twenty-two postmenopausal women (50-70 years) were recruited from The Second University Hospital, West China University of Medical Sciences, Chengdu and participated in the pre-test. Another 21 women (50-70 years) were randomly selected from the general population of all five districts of Chengdu and participated in the reliability and validity sub-studies. RESULTS: Energy, protein, carbohydrate, magnesium and sodium intakes in this sample were less than the Recommended Dietary Allowances (RDAs) for 45-70-year-old women in China. Intake of non-cooking fat was higher than the Chinese RDA. Pearson correlation coefficients and intra-class correlation coefficients (ICCs) for reliability of the VE FFQ ranged from 0.51 to 0.85 and from 0.51 to 0.81, respectively; for the WE FFQ, they ranged from 0.22 to 0.86 and from 0.21 to 0.81. Correlation coefficients and ICCs for validity of the WE FFQ ranged from 0.36 to 0.69 and from 0.34 to 0.57, respectively; corresponding values for the VE FFQ were -0.30 to 0.65 and -0.14 to 0.65. CONCLUSIONS: Both the VE and WE FFQs were reliable and valid except for sodium intake. The VE FFQ provided more valid estimates of nutrient intakes than did the WE FFQ.

Aged↗
PubMed2000

Prediction and validation of fat-free mass in the lower limbs of young adult male Rugby Union players using dual-energy X-ray absorptiometry as the criterion measure.

The aim was to derive and cross-validate prediction equations to estimate fat-free mass (FFM) in the lower limbs of young adult male Rugby Union players. Thirty players of mean +/- SD age of 21.1 +/- 2.1 years were recruited. Bone mineral mass, fat mass and lean tissue mass were measured with a Hologic QDR 1000/W whole-body scanner. Anthropometry included circumferences, segmental leg lengths and skinfold thicknesses. Players were divided randomly into prediction (n = 15) and cross-validation (n = 15) samples. Regression equations were derived from the prediction sample and validated on the cross-validation sample. Seven equations were formulated to predict leg FFM. The two equations providing the lowest standard errors of estimate were leg length with circumferences at the knee (0.7262) and calf (0.7382); the multiple correlation was 0.83 in both instances. Cross-validation statistics found no significant differences (p > 0.05) between measured (12.4 +/-1.5 kg) and predicted leg FFM (12.1-12.4 kg). The smallest mean difference was -0.05 kg, the largest 0.26 kg; these were equivalent to -0.4 and 2.1% of the measured leg FFM respectively. Correlations between measured and predicted leg FFM were reasonably high (0.79-0.90, p < 0.001). The ratio limits of agreement confirmed that there was little bias between measured and predicted leg FFM (1.00-1.02) and a good level of agreement (1.12-1.16). Because prediction equations tend to be age, gender and population specific, unless validated for other athletic groups, the present equations should be applied to male Rugby Union players with characteristics similar to those described.

Absorptiometry, Photon↗
PubMed2004

Validation of assembled nucleic acid-based tests in diagnostic microbiology laboratories.

Medical microbiology and virology laboratories use nucleic acid tests (NAT) to detect genomic material of infectious organisms in clinical samples. Laboratories choose to perform assembled (or in-house) NAT if commercial assays are not available or if assembled NAT are more economical or accurate. One reason commercial assays are more expensive is because extensive validation is necessary before the kit is marketed, as manufacturers must accept liability for the performance of their assays, assuming their instructions are followed. On the other hand, it is a particular laboratory's responsibility to validate an assembled NAT prior to using it for testing and reporting results on human samples. There are few published guidelines for the validation of assembled NAT. One procedure that laboratories can use to establish a validation process for an assay is detailed in this document. Before validating a method, laboratories must optimise it and then document the protocol. All instruments must be calibrated and maintained throughout the testing process. The validation process involves a series of steps including: (i) testing of dilution series of positive samples to determine the limits of detection of the assay and their linearity over concentrations to be measured in quantitative NAT; (ii) establishing the day-to-day variation of the assay's performance; (iii) evaluating the sensitivity and specificity of the assay as far as practicable, along with the extent of cross-reactivity with other genomic material; and (iv) assuring the quality of assembled assays using quality control procedures that monitor the performance of reagent batches before introducing new lots of reagent for testing.

DNA, Bacterial↗
PubMedDate not supplied

The female sexual function index (FSFI): cross-validation and development of clinical cutoff scores.

The Female Sexual Function Index (FSFI) is a brief multidimensional scale for assessing sexual function in women. The scale has received initial psychometric evaluation, including studies of reliability, convergent validity, and discriminant validity (Meston, 2003; Rosen et al., 2000). The present study was designed to crossvalidate the FSFI in several samples of women with mixed sexual dysfunctions (N = 568) and to develop diagnostic cut-off scores for potential classification of women's sexual dysfunction. Some of these samples were drawn from our previous validation studies (N = 414), and some were added for purposes of the present study (N = 154). The combined data set consisted of multiple samples of women with sexual dysfunction diagnoses (N = 307), including female sexual arousal disorder (FSAD), hypoactive sexual desire disorder (HSDD), female sexual orgasm disorder (FSOD), dyspareunia/vaginismus (pain), and multiple sexual dysfunctions, in addition to a large sample of nondysfunctional controls (n = 261). We conducted analyses on the individual and combined samples, including replicating the original factor structure using principal components analysis with varimax rotation. We assessed Cronbach's alpha (internal reliability) and interdomain correlations and tested discriminant validity by means of a MANOVA (multivariate analysis of variance; dysfunction diagnosis x FSFI domain), with Bonferroni-corrected post hoc comparisons. We developed diagnostic cut off scores by means of standard receiver operating characteristics-curves and the CART (Classification and Regression Trees) procedure. Principal components analysis replicated the original five-factor structure, including desire/arousal, lubrication, orgasm, pain, and satisfaction. We found the internal reliability for the total FSFI and six domain scores to be good to excellent, with Cronbach alpha's >0.9 for the combined sample and above 0.8 for the sexually dysfunctional and nondysfunctional samples, independently. Discriminant validity testing confirmed the ability of both total and domain scores to differentiate between functional and nondysfunctional women. On the basis of sensitivity and specificity analyses and the CART procedure, we found an FSFI total score of 26.55 to be the optimal cut score for differentiating women with and without sexual dysfunction. On the basis of this cut-off we found 70.7% of women with sexual dysfunction and 88.1% of the sexually functional women in the cross-validation sample to be correctly classified. Addition of the lubrication score in the model resulted in slightly improved specificity (from .707 to .772) at a slight cost of sensitivity (from .881 to .854) for identifying women without sexual dysfunction. We discuss the results in terms of potential strengths and weaknesses of the FSFI, as well in terms of further clinical and research implications.

Adult↗
PubMed2003

Validation and sensitivity analysis of probabilistic models of dietary exposure to micronutrients: an example based on vitamin B6.

Probabilistic modelling can be used to get an insight into the variability and uncertainty of the nutrient intake in a population. When a probabilistic model is used, it is important that it is validated. Furthermore, a sensitivity analysis of the model output can give an insight into the most important input variables of the model and can be used as an aid to describe the reliability of the model. In this study, four models to estimate vitamin B(6) intake among males and females were validated using the method of Kaaks et al. This method compares the relationship between three different kind of measurements with the unknown 'true' intake. In each of these four models, only one input variable (concentration or bioavailability) was changed compared with a reference model. A sensitivity analysis was also performed. The results of the validation showed that for males, a model using a fixed bioavailability factor at the food group level was valid, while for females a model using either a fixed value or a distribution for the bioavailability factor was valid. Use of a distribution for the concentration of vitamin B(6) in supplements was not valid. The results of the sensitivity analysis showed that the concentration of vitamin B(6) in food and supplements was the key contributor to variability and uncertainty in the model estimates of vitamin B(6) intake, in both males and females. All results indicated that when taking variability and uncertainty into account by using probabilistic modelling, the effect on the nutrient intake for nutrients that are present in many common eaten foods, is small. For these broadly available nutrients, fixed concentrations and bioavailability factors give a good estimate of the nutrient intake in a population. When using probabilistic modelling, it is very important to collect more actual information about the concentration.

Adult↗
PubMedDate not supplied

Validation study of the three-objects-three-places test: a screening test for Alzheimer's disease.

The aim of the present study was to validate a short, ecological test of episodic memory for the screening of Alzheimer's disease (AD). The validation was performed by computing intrarater reliability, homogeneity, internal coherence, convergent, discriminant and known group validities in the performance of normal subjects (N = 65), mild cognitive impairment (MCI) patients (N = 114), and AD (N = 44) and non-AD demented (N = 39) patients. Intrarater reliability was 0.88, homogeneity ranged from 0.81 to 0.97, and internal coherence was 0.87. With respect to convergent and discriminant validities, the test loaded strongly on memory factor (value = 0.64) and weakly on other nonmemory factors. The known group validity showed a specificity between 87% and 91% and a sensitivity between 92% and 100% in correctly identifying AD in age classes ranging from 50 to 65 and 66 to 80 years. The test is a valid instrument for the screening of AD.

Aged↗
PubMed2005

Validation of the World Health Organization Alcohol, Smoking and Substance Involvement Screening Test (ASSIST): report of results from the Australian site.

The concurrent, construct, discriminative and predictive validity of the World Health Organization's Alcohol Substance Involvement Screening Test (ASSIST) were examined in an Australian sample. One hundred and fifty participants, recruited from drug treatment (n = 50) and primary health care (PHC) settings (n = 100), were administered a battery of instruments at baseline and a modified battery at 3 months. Measures included the ASSIST; the Addiction Severity Index-Lite (ASI-Lite); the Severity of Dependence Scale (SDS); the MINI International Neuropsychiatric Interview (MINI-Plus); the Rating of Injection Site Condition (RISC); the Drug Abuse Screening Test (DAST); the Alcohol Use Disorders Identification Test (AUDIT); the Revised Fagerstrom Tolerance Questionnaire (RTQ); and the Maudsely Addiction Profile (MAP). Concurrent validity was demonstrated by significant correlations between ASSIST scores and scores from the ASI-lite, SDS, AUDIT and DAST; and significantly greater ASSIST scores for those with diagnoses of abuse or dependence. Construct validity was established by significant correlations between ASSIST scores and measures of risk factors for the development of drug and alcohol problems. Participants diagnosed with attention deficit/hyperactivity disorder or antisocial personality disorder had significantly higher ASSIST scores than those not diagnosed as such. Discriminative validity was established by the capacity of the ASSIST to discriminate between substance use, abuse and dependence. ROC analysis was able to establish cut-off scores for an Australian sample, with suitable specificities and sensitivities for most substances. Predictive validity was demonstrated by similarity in ASSIST scores obtained at baseline and at follow-up. The findings demonstrated that the ASSIST is a valid screening test for psychoactive substance use in individuals who use a number of substances and have varying degrees of substance use.

Adult↗
PubMed2006

Reliability and validity of the Hindi version of the Neck Pain and Disability Scale in cervical radiculopathy patients.

PURPOSE: To assess the reliability and validity of the Neck Pain and Disability Scale (NPAD) translated into Hindi. METHOD: Following a pilot study to ascertain uncertainties with existing terminology in the NPAD scale, a cervical radiculopathy patient cohort (n = 63) was assessed with the translated NPAD. Reliability was assessed by regression analysis for test-retest and by item-factor and factor-total score correlations. Face validity was compared in a cross-sectional design study with an asymptomatic group (n = 38). Convergent and divergent validity were investigated by correlating the NPAD scores with the Numerical Pain Rating Scale (NPRS) for neck and arm pain, and 10 cm long VAS Activity and VAS Depression scales. RESULTS: ICC values for test-retest NPAD total and factor scores were >0.92 and R2 values >0.912. Pearson product moment correlation of item vs. factor scores varied from 0.17 - 0.91 and for factor vs. total scores 0.72 - 0.91. Differences in NPAD scores between the patient and the asymptomatic group were significant (t = 30.90, p < 0.05). Convergent validity was explained when Factor 2 (minus item 20) was correlated (r = 0.67) with NPRS maximum value scores. Divergent validity was illustrated by low correlation with VAS Activity (r = 0.15) and negative correlation with VAS Depression (r = -0.80) scores. CONCLUSION: Based on the results of this study, the Hindi version of the NPAD is a reliable and valid instrument for the assessment of pain and disability in cervical radiculopathy patients.

Adult↗
PubMed2005

Reliability and validity of the Swedish version of the Fatigue Impact Scale (FIS).

Fatigue is a complex phenomenon that, for those not affected, is hard to understand. To achieve better assessments, caregivers need reliable and valid tools. The aim of this study was to investigate the reliability and validity of the Swedish version of the Fatigue Impact Scale (FIS) among working-aged individuals diagnosed with multiple sclerosis (MS), as well as in a comparative group randomly selected from the general population in the same geographical area. Both individuals with MS (n=161) and individuals recruited from the general population (n=194) participated in the study. A questionnaire was used for the data collection. The data were analysed using non-parametric statistical methods. Reliability of FIS was addressed by item-to-item and item-to-total correlations. Concurrent validity was tested for by analysing correlations between the FIS and general questions, and construct validity by investigation of differences in the FIS scores between known groups. The FIS was found to be homogenous, with item-to-total correlation coefficients of 0.42 < or = s < or = .86 (p <0.001), reflecting the instrument's reliability. The correlations between the FIS and the general questions confirm its concurrent validity, 0.27 < or = s < or = .84 (p <0.001). The differences in FIS scores between known groups demonstrate its construct validity. Furthermore, the FIS showed the ability to discriminate between groups of individuals with differences in perceived impact of fatigue.

Activities of Daily Living↗
PubMed2006

WHO diagnostic criteria as a validation tool for the diagnosis of diabetes mellitus: a study in five European countries.

OBJECTIVE: In 1999, the World Health Organization (WHO) published new diagnostic criteria for diabetes mellitus (DM). The cut-off value of the fasting plasma glucose concentration was lowered from 7.8 to 7.0 mmol/l. The WHO criteria were used to validate the diagnosis made by the general practitioner, and to compare the diagnostic validity of diabetes mellitus in different countries. METHODS: We retrospectively analysed 2556 newly diagnosed diabetics. Incidence was calculated according to the 1999 WHO criteria. Data were collected in general practice networks in five European countries or regions (Belgium, England, the Netherlands, Portugal, Spain). RESULTS: According to the WHO criteria, 82% of the cases were valid diagnoses. Compared to the total group, in Spain, significantly more diagnoses were in agreement with the WHO criteria, whereas this number was significantly lower in England and Portugal. From the patients whose diagnosis was not in agreement with the WHO criteria, significantly more were women than men. CONCLUSION: By using the WHO diagnostic criteria, the international standard, as a validation tool, we show that the diagnoses of diabetes mellitus made in primary care are valid. Furthermore, we show that these diagnoses are comparable between countries. Therefore, information from general practice registration networks is a valuable and valid source for international comparisons.

Adolescent↗
PubMed2005

Validity of impedance-based equations for the prediction of total body water as measured by deuterium dilution in African women.

BACKGROUND: Little information is available on the validity of simple and indirect body-composition methods in non-Western populations. Equations for predicting body composition are population-specific, and body composition differs between blacks and whites. OBJECTIVE: We tested the hypothesis that the validity of equations for predicting total body water (TBW) from bioelectrical impedance analysis measurements is likely to depend on the racial background of the group from which the equations were derived. DESIGN: The hypothesis was tested by comparing, in 36 African women, TBW values measured by deuterium dilution with those predicted by 23 equations developed in white, African American, or African subjects. These cross-validations in our African sample were also compared, whenever possible, with results from other studies in black subjects. RESULTS: Errors in predicting TBW showed acceptable values (1.3-1.9 kg) in all cases, whereas a large range of bias (0.2-6.1 kg) was observed independently of the ethnic origin of the sample from which the equations were derived. Three equations (2 from whites and 1 from blacks) showed nonsignificant bias and could be used in Africans. In all other cases, we observed either an overestimation or underestimation of TBW with variable bias values, regardless of racial background, yielding no clear trend for validity as a function of ethnic origin. CONCLUSIONS: The findings of this cross-validation study emphasize the need for further fundamental research to explore the causes of the poor validity of TBW prediction equations across populations rather than the need to develop new prediction equations for use in Africa.

Adolescent↗