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Reliability and validity of two tests for non-verbal memory.

Because of its lenient effects on memory, unilateral electroconvulsive therapy (ECT) on the non-dominant hemisphere is routinely used in most ECT units in the Scandinavian countries. Considering the neuropsychological peculiarities of the non-dominant hemisphere, two tests were constructed to evaluate the effect of ECT on non-verbal memory. The tests are characterized by visual mode of administration and complex figurative items. They can measure both immediate and delayed memory and exist in two parallel forms. Analysis of a number of studies on unilateral non-dominant and dominant ECT indicates that the two non-verbal memory tests have good reliability and validity. Convergent validity between the two non-verbal memory tests, discriminant validity against tests of verbal memory, and criterion-related validity in relation to the influence of different treatment modalities, indicate the tests as valid instruments for measuring non-verbal memory. The two test forms show satisfactory parallelism. Together with tests of verbal memory, the total battery provides an all-round instrument for studying memory functions after ECT or other cerebral influences.

Dominance, Cerebral↗

Greek version of the General Health Questionnaire: accuracy of translation and validity.

The purpose of this study was to examine the accuracy of translation and to test the validity of the Greek version of the General Health Questionnaire (GHQ). In the translation study, the English and the Greek versions of the GHQ were administered to a sample of 50 bilingual respondents. The internal consistency, item-by-item and the subject-by-subject analysis have shown that the 2 versions are equivalent and therefore the Greek translation is highly accurate. In the validity study, 100 consecutive patients attending an internal medicine outpatient clinic completed the Greek version of the GHQ-60 and were interviewed independently using the Present State Examination (PSE). The validity of the shorter forms of the questionnaire (GHQ-30 and GHQ-28) was tested by disembedding the relevant items from the larger set. The correlations obtained between the scores of the questionnaire and the PSE ratings, as well as all the validity indices (sensitivity, specificity, positive predictive value, negative predictive value and overall misclassification rate) were quite satisfactory for all the GHQ forms, thus confirming the validity of the questionnaire in its Greek version. The best cut-off points as found by receiver-operating characteristics analysis were 11/12 for the GHQ-60, 5/6 for the GHQ-30 and 4/5 for the GHQ-28. The revised (CGHQ) scoring system for the GHQ-30 has not been proved superior to the conventional scoring method. The above results are discussed in relation to the pertinent literature and especially the studies carried out in similar settings and in countries with similar cultural backgrounds.

Adolescent↗

Using the Delphi technique to examine the content validity of nursing diagnoses.

Official labeling of phenomena that nurses diagnose and treat requires that researchers validate the existence of proposed diagnoses. One part of the validation process is the examination of content validity. The Delphi technique is a useful methodologic technique for such an examination. This article describes the characteristics, background, advantages, and disadvantages of the Delphi technique, as well as suggested strategies for using it to validate nursing diagnoses. In discussing strategies for using the Delphi technique to validate nursing diagnoses, the format, essential components, and steps of each round of the traditional and modified Delphi procedure are addressed. Round I of the traditional Delphi technique involves selection of a panel of content experts, developing and mailing questionnaires and content analysis, and generating a list of defining characteristics and operational definitions for a nursing diagnosis. Round II involves developing and mailing questionnaires, determining percentage of agreement, and providing statistical analysis. Round III includes developing and mailing questionnaires and providing statistical analysis of data. Round IV consists of developing and mailing the final report, which includes a statistical summary of individual and grouped responses in round III, as well as a minority report. The format and statistical analysis of the modified Delphi procedure is similar to rounds II, III, and IV of the traditional Delphi technique, except the modified technique usually will require only three rounds.

Delphi Technique↗

Modification of the diagnostic content validity model.

Diagnostic content validation of nursing diagnoses is a recommended means to confirm the defining characteristics necessary to establish a specific nursing diagnosis. The diagnostic content validity model has been used in numerous studies to develop lists of major and minor defining characteristics recommended by experts as being present in patients with specific diagnoses. The authors provide an overview of the diagnostic content validity model, review the meaning and purposes of content validity, discuss problems with information processing, and suggest revisions to the diagnostic content validity model. Incorporation of these changes may improve the usability of nursing diagnoses in clinical practice, education, and research.

Humans↗

Processes and methodologies for research validation of nursing diagnoses.

TOPIC: Research validation of nursing diagnoses. PURPOSE: To provide a historical review of processes and methodologies for research validation of nursing diagnoses and suggested directions for future nursing diagnosis research. SOURCES: Nursing diagnosis research methodologies and processes from the Invitational Conference on Research Methods for Validating Nursing Diagnoses, Nursing Diagnosis: The Journal of Nursing Language and Classification, and the North American Nursing Diagnosis Association (NANDA) conference proceedings for the first through the 12th conference. CONCLUSIONS: Future nursing diagnosis research should include concept analysis, expert validation, clinical validation, instrument development, larger studies, powerful statistical analyses, replication and comparison of studies, and concerted efforts to support group research activities that target priority areas of research.

Data Interpretation, Statistical↗

Validity of self-reported tooth counts during a telephone screening interview.

OBJECTIVES: Telephone screening has become a common method used in health services research to identify efficiently persons in specific populations of interest. In this research, we used a large-scale telephone screening survey to assess: (1) the effectiveness of the telephone method in gathering tooth count information by measuring response rate (cooperation) to specific questions and (2) the validity of subjects' reports of the number of remaining natural teeth. METHODS: We used a telephone screening methodology to identify dentate persons (at least one natural tooth remaining) who were 45 years old or older and resided in one of four counties of north Florida. At a second stage, a sample of the telephone screening participants was selected for further study, which consisted of a baseline in-person interview and a clinical examination. We compared the number of remaining teeth reported during the telephone interview with the number determined at baseline examination. RESULTS: The telephone method was effective at gathering tooth count information, although response rates varied with the level of specificity required. Almost all subjects reported the number of teeth at least at the nominal and ordinal levels, but fewer than three-fourths reported the number at the interval level. When the unit of analysis was the overall sample, self-reported number of teeth was a valid measure of the true number. When the unit of analysis was the individual subject, validity was associated with certain clinical and sociodemographic factors. CONCLUSIONS: When the unit of analysis is the overall sample, these results suggest that self-reported tooth counts during a telephone interview are sufficiently valid to meet all but the most stringent data requirements. When the unit of analysis is the individual subject, these tooth counts may not be valid, depending upon the degree of specificity required and subject characteristics.

Age Factors↗

Validity of two methods for assessing oral health status of populations.

OBJECTIVE: This investigation assessed two methods for estimating epidemiologic indicators of oral health status among children: (1) a visual-only screening, performed independently by a dental hygienist and a registered nurse; and (2) a parent- or guardian-completed questionnaire. The indicators included dichotomous variables measuring dental caries and treatment needs, presence of sealants, injuries to the anterior teeth, and dental fluorosis. METHODS: Following training and calibration, data were collected over an eight-day period in April 1994 among 632 elementary schoolchildren (aged 5 to 12 years) in Monticello, Georgia. Both screening and questionnaire findings were compared pairwise with results from visual-tactile examinations done by a dentist. Validity, represented by sensitivity, specificity, and predictive values, was assessed for screening results from the dental hygienist, the nurse, and the parent-completed questionnaire. RESULTS: Validity was high for screening for caries and treatment needs (> 90% for sensitivity, specificity, and predictive values in a sample having 30% to 40% prevalence). Less valid data--mainly an effect of false negatives--were obtained for fluorosis, injuries, and presence of sealants. No significant difference in validity was observed between the nurse and the dental hygienist. One-third of respondents to the questionnaire did not know if their children needed fillings (a proxy for untreated decay) or had received sealants; only knowledge of restorations was comparable to results from screening. Intraexaminer reliability for the two screeners ranged from 85 to 100 for percent agreement and 0.70 to 0.93 for kappa scores. CONCLUSIONS: Screening by dental hygienists or nurses can provide valid data for surveillance of dental caries and treatment needs. Training for visual assessment of fluorosis and injuries must be improved to diminish the proportion of false negatives. A parent-completed questionnaire is less effective than visual screening for evaluating oral health status in children.

Child↗

The validity and reliability of maternal recall of breastfeeding practice.

In large epidemiologic studies, information on breastfeeding practice is often collected from maternal recall through interviews, but there is concern about the accuracy of the data, especially when mothers are asked to recall their practices from many years earlier. This review examines the validity and reliability of maternal recall of breastfeeding history using 11 studies published between 1966 and 2003 in English with a sample of 10 or more. Validity is the degree to which recall compares with a validation standard or reference, and reliability refers to the degree to which the breastfeeding practices obtained by recall are repeatable over time. The existing studies suggest that maternal recall is a valid and reliable estimate of breastfeeding initiation and duration, especially when the duration of breastfeeding is recalled after a short period (< or = 3 years). Validity and reliability of maternal recall for the age at introduction of food and fluids other than breast milk are less satisfactory. Further and more extensive studies on maternal recall of breastfeeding history and ways to improve such recall are warranted.

Adult↗

The oral hygiene performance test: development and validation of dental dexterity scale for the elderly.

This paper describes a test which was developed for use in assessing the functional oral hygiene status of an elderly population. The instrument was tested among 80 community-dwelling elderly subjects 65 or more years old. The instrument, the Oral Hygiene Performance Test [OHPT], is a direct-observation measure which objectively quantifies the individual's ability to perform oral hygiene and thus reduces subjective evaluation. The test utilized several items from other already-validated instruments currently in use in geriatric medicine to assess functional abilities in a geriatric population. Additional items were developed by the research team and were included in this 17-item test. The OHPT was validated with common measures of physical function and direct-observation measures. Construct validity was assessed by comparison of the OHPT scores with other commonly used measures of other dimensions. The instrument proved to be reliable and demonstrated construct as well as concurrent validity. It appears that the OHPT can prove useful to clinicians in assessing the oral physical function of elderly patients with regard to their maintenance of oral hygiene. Because the OHPT is a direct-observation instrument, it can even elicit higher functions in elderly patients. While effective among the studied population, the instrument may still need to be validated among more diverse populations, such as various ethnic groups and demented or severely impaired populations.

Black or African American↗

Assessing the quality of solution nuclear magnetic resonance structures by complete cross-validation.

Structure determination of macromolecules in solution by nuclear magnetic resonance (NMR) spectroscopy involves the fitting of atomic models to the observed nuclear Overhauser effect (NOE) data. Complete cross-validation has been used to define reliable and unbiased criteria for the quality of solution NMR structures. The method is based on the partitioning of NOE data into test sets and the cross-validation of statistical quantities for each of the test sets. A high correlation between cross-validated measures of fit, such as distance bound violations and NMR R values, and the quality of solution NMR structures was observed. Less complete data resulted in poorer satisfaction of the cross-validated measures of fit. Optimization of cross-validated measures of fit will likely produce solution NMR structures with maximal information content.

Bacterial Proteins↗

Comparative, collaborative, and on-site validation of a TaqMan PCR method as a tool for certified production of fresh, campylobacter-free chickens.

Certified Campylobacter-free poultry products have been produced in Denmark since 2002, the first example of fresh (unprocessed and nonfrozen) chickens labeled "Campylobacter free." This success occurred partly through use of a 4-hour gel-based PCR testing scheme on fecal swabs. In this study, a faster, real-time PCR approach was validated in comparative and collaborative trials, based on recommendations from the Nordic system for validation of alternative microbiological methods (NordVal). The comparative real-time PCR trial was performed in comparison to two reference culture protocols on naturally contaminated samples (99 shoe covers, 101 cloacal swabs, 102 neck skins from abattoirs, and 100 retail neck skins). Culturing included enrichment in both Bolton and Preston broths followed by isolation on Preston agar and mCCDA. In one or both culture protocols, 169 samples were identified as positive. The comparative trial resulted in relative accuracy, sensitivity, and specificity of 98%, 95%, and 97%, respectively. The collaborative trial included nine laboratories testing neck skin, cloacal swab, and shoe cover samples, spiked with low, medium, and high concentrations of Campylobacter jejuni. Valid results were obtained from six of the participating laboratories. Accuracy for high levels was 100% for neck skin and cloacal swab samples. For low levels, accuracy was 100% and 92% for neck skin and cloacal swab samples, respectively; however, detection in shoe cover samples failed. A second collaborative trial, with an optimized DNA extraction procedure, gave 100% accuracy results for all three spiking levels. Finally, on-site validation at the abattoir on a flock basis was performed on 400 samples. Real-time PCR correctly identified 10 of 20 flocks as positive; thus, the method fulfilled the NordVal validation criteria and has since been implemented at a major abattoir.

Animals↗

Measuring the effectiveness of cataract surgery: the reliability and validity of a visual function outcomes instrument.

AIMS: To assess test-retest reliability and validity of the "TyPE" patient self assessed visual function questionnaire, as part of a study in two hospitals measuring the effectiveness of cataract surgery. The American TyPE questionnaire had minor adaptations made for use in Britain. METHODS: Test-retest reliability was assessed on 63 out of 378 adult cataract surgery patients in the study, using Spearman correlation coefficients and kappa coefficients of agreement. "Construct" validity was evaluated by comparing the association between changes in visual function questionnaire scores after surgery, with patients' perception of change in visual function obtained by independent interview of 24 patients. RESULTS: The TyPE questionnaire items showed very good test-retest reliability. Average Spearman and kappa coefficients for 39 patients from hospital 1 were 0.93 and 0.84 respectively. Spearman and kappa coefficients of 0.9 and 0.81 were obtained for those nine patients in hospital 2 where both the test and retest questionnaires were filled in by the same people. However, for the 15 patients from hospital 2, where the questionnaire was filled in by different people in the retest, reliability was less good: the Spearman coefficients were still high, average 0.72, but the kappa coefficients were poor, 0.27. Good construct validity was exhibited, with a correlation of 0.79 between change in distance vision score from the questionnaires and the independent interview. CONCLUSIONS: The adapted TyPE questionnaire is both very reliable and has good construct validity. The kappa coefficient should be used wherever possible to evaluate reliability. The test-retest reliability and validity and practicability of other visual function questionnaires have not been assessed adequately, and further development should be carried out of all such questionnaires, so that they may be introduced into routine clinical care.

Activities of Daily Living↗

The left ventricular dysfunction questionnaire (LVD-36): reliability, validity, and responsiveness.

OBJECTIVE: To examine the reliability, validity, and responsiveness of a new health status measure (LVD-36) for patients with left ventricular dysfunction which was designed with emphasis on content validity, clarity, brevity, and ease of use. DESIGN: At baseline, patients completed the LVD-36 and a range of measures reflecting general health and disease severity. The LVD-36 was repeated after one week. After six months, it was repeated again, along with a transition question to measure global changes in health. SETTING: Patients were recruited from the cardiology and general medical clinics at a south west London hospital. PATIENTS: 60 patients with chronic left ventricular dysfunction. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Short form 36 questionnaire (SF-36), Minnesota living with heart failure questionnaire (LIhFE), New York Heart Association criteria, and exercise performance and echocardiographic tests. RESULTS: The LVD-36 showed good internal consistency (kappa = 0.95) and repeatability (r(i) = 0.95). Its scores were significantly associated with SF-36 mental and physical component scores (r = -0. 48 and -0.75; p < 0.0001), with exercise capacity (r = -0.52; p < 0. 0001), and with systolic shortening fraction (r = -0.27; p < 0.05). Change in the LVD-36 over six months was associated with change in overall health (F = 5.7; p < 0.001). In tests of validity and responsiveness, the LVD-36 performed similarly to or marginally better than the LIhFE. CONCLUSIONS: The LVD-36 showed a high level of reliability and validity, and appears to measure changes in health. It provides a short, simple, valid, and reliable measure of health status in patients with left ventricular dysfunction.

Aged↗

Developing valid indicators of injury incidence for "all injury".

BACKGROUND/AIMS: This paper focuses on the methods used to develop indicators for "all injury" incidence for the New Zealand Injury Prevention Strategy (NZIPS), launched in June 2003. Existing and previously proposed New Zealand national non-fatal injury indicators exhibited threats to validity. Population/ SETTING: The total population of New Zealand. METHODS: The authors proposed fatal and new non-fatal injury indicators for "all injury" based on national mortality and hospitalizations data. All of the candidate indicators were subjected to a systematic assessment of validity, using the International Collaborative Effort on Injury Statistics (ICE) criteria. Based on the results of that validation, the authors identified four proposed NZIPS indicators. RESULTS: The proposed "all injury" indicators were as follows: age standardized injury mortality rate per 100 000 person-years at risk; number of injury deaths; age standardized serious non-fatal injury rate per 100 000 person-years at risk; and number of cases of serious non-fatal injury. The authors identified no threat-to-validity when assessed against the ICE criteria. The estimated numbers and rates of serious non-fatal injury increased over the period, in contrast to the numbers and rates of fatal injury. CONCLUSION: The authors have proposed serious non-fatal injury indicators that they judge suffer substantially less bias than traditional non-fatal injury indicators. This approach to indicator development is consistent with the view that before newly proposed indicators are promulgated, they should be subjected to formal validation. The authors are encouraged that the New Zealand Government has accepted these arguments and proposed indicators, and are starting to act on some of their recommendations, including the development of complementary indicators.

Bias↗

Validity of self reported diagnoses of cancer in a major Spanish prospective cohort study.

INTRODUCTION: This study aims to assess the validity of self reported diagnoses of cancer by persons recruited for the Spanish EPIC (European prospective investigation into cancer and nutrition) cohort study and to identify variables associated with correctly reporting a diagnosis of cancer. METHODS: 41 440 members of EPIC were asked at the time of recruitment whether they had been diagnosed with cancer and the year of diagnosis and site. The process of validating self reported diagnoses of cancer included comparison of the cohort database with the data from the population based cancer registries. Cancer diagnostic validity tests were calculated. The association between a correct report and certain sociodemographic, tumour related, or health related variables were analysed by logistic regression. RESULTS: The overall sensitivity of self reported diagnoses of cancer is low (57.5%; 95% CI: 51.9 to 63.0), the highest values being shown by persons with a higher level of education or with a family history of cancer and the lowest values by smokers. Breast and thyroid cancers are those with the highest diagnostic validity and uterus, bladder, and colon-rectum those with the lowest. In both sexes the variables showing a significant association with a correct report of cancer are: higher education level, number of previous pathologies, invasive tumour, and, in women, a history of gynaecological surgery. CONCLUSIONS: The overall sensitivity of self reported diagnoses of cancer is comparatively low and it is not recommended in epidemiological studies for identifying tumours. However, self reported diagnoses might be highly valid for certain tumour sites, malignant behaviour, and average to high levels of education.

Adult↗

Validation of a short telephone administered questionnaire to evaluate dietary interventions in low income communities in Montreal, Canada.

OBJECTIVE: To validate an adaptation of a short questionnaire measuring behaviour related to selecting low fat diets. The questionnaire was adapted for telephone use in a low income, low education population. DESIGN: The factorial structure of the 38 item adaptation was studied in a population based random sample of 1432 adults. Seven day test-retest reliability was measured in a convenience sample of 93 adults, and criterion related validity in measuring fat was assessed against a dietitian administered diet history in another convenience sample of 81 adults. SETTING: Adults aged 18-65 years living in low income, inner city neighbourhoods in Montreal, Canada. RESULTS: Principal components analysis identified five food factors: avoid fat, junk food, high fat traditional foods, low fat substitutes for high fat foods, and modification of meat to reduce fat. Two factors were similar to those of the original version. Internal consistency of the subscales ranged from 0.49-0.72. Test-retest reliability ranged from 0.72-0.90. Validation of the subscales against usual dietary intake indicated that the "junk food" factor, arising from questions added to the original questionnaire to reflect local dietary habits, was most closely related to fat intake (r = 0.48; p < 0.001). CONCLUSION: This telephone adaptation provides an inexpensive and valid method of measuring fat intake. However, these results suggest that adaptations of existing dietary instruments should be validated in the populations for which they are intended before they are used.

Adult↗

Development and validation of the Essen Intracerebral Haemorrhage Score.

BACKGROUND: Spontaneous intracerebral haemorrhage (ICH) accounts for the highest in-hospital mortality of all stroke types. Nevertheless, outcome is favourable in about 30% of patients. Only one model for the prediction of favourable outcome has been validated so far. OBJECTIVE: To describe the development and validation of the Essen ICH score. METHODS: Inception cohorts were assessed on the National Institutes of Health stroke scale (NIH-SS) on admission and after follow up of 100 days. On the basis of previously validated clinical variables, a simple clinical score was developed to predict mortality and complete recovery (Barthel index after 100 days>or=95) in 340 patients with acute ICH. Subscores for age (<60=0; 60-69=1; 70-79=2; >or=80=3), NIH-SS level of consciousness (alert=0; drowsy=1; stuporose=2; comatose=3), and NIH-SS total score (0-5=0; 6-10=1; 11-15=2; 16-20=3; >20 or coma=4) were combined into a prognostic scale with <3 predicting complete recovery and >7 predicting death. The score was subsequently validated in an external cohort of 371 patients. RESULTS: The Essen ICH score showed a high prognostic accuracy for complete recovery and death in both the development and validation cohort. For prediction of complete recovery on the Barthel index after 100 days, the Essen ICH score was superior to the physicians' prognosis and to two previous prognostic scores developed for a slightly modified outcome. CONCLUSIONS: The Essen ICH score provides an easy to use scale for outcome prediction following ICH. Its high positive predictive values for adverse outcomes and easy applicability render it useful for individual prognostic indications or the design of clinical studies. In contrast, physicians tended to predict outcome too pessimistically.

Age Factors↗

Are the modified "simple questions" a valid and reliable measure of health related quality of life after stroke? United Kingdom Collaborators in the International Stroke Trial.

OBJECTIVES: Two "simple questions" were developed as a minimalist measurement tool to assess outcome in large trials and epidemiological studies after stroke. A previous study of their validity had disclosed ambiguities in their wording. In this study, the clarity, validity, and reliability of a modified version of these simple questions were examined. The relation between patients' responses to these questions and two widely used generic measures of health related quality of life were also studied. METHODS: A hospital based stroke register cohort of 152 patients, who were all visited at home by a study nurse, was used to study validity. A cohort of 1753 patients derived from the International Stroke Trial was used to study the relation with measures of quality of life. The sensitivity, specificity, and accuracy with which responses to each question predicted the patients' outcome measured using standard instruments was assessed. The distribution of scores for the EuroQol and SF-36 was examined for patients classified as dependent, independent, and fully recovered by the combined use of the modified simple questions. RESULTS: The modified "dependency" question had excellent sensitivity (>85%), specificity (>79%), and accuracy (>82%) for identifying dependency after stroke. The "problems" question had good sensitivity (65-88%) and moderate specificity (36-72%) for the detection of problems in a broad range of domains. The combined use of the modified dependency and problems questions provided a valid, simple, and reliable overall indicator of health related quality of life after stroke. CONCLUSIONS: The modified simple questions have excellent face validity and good measurement properties for the assessment of outcome after stroke. They are particularly well suited for large epidemiological studies and randomised trials.

Humans↗