The validity of the MacNew Quality of Life Questionnaire in heart disease.

Background A previous review suggested that the MacNew Quality of Life Questionnaire was the most appropriate disease-specific measure of health-related quality of life among people with ischaemic heart disease. However, there is ambiguity about the allocation of items to the three factors underlying the MacNew and the factor structure has not been confirmed previously among the people in the UK. Methods The MacNew Questionnaire and the SF-36 were administered to 117 newly admitted patients to a tertiary referral centre in Northern Ireland. All patients had been diagnosed with ischaemic heart disease. Results A confirmatory factor analysis was conducted on the factor structure of the MacNew and the model was found to be an inadequate fit of the data. A quantitative and qualitative analysis of the items suggested that a five factor solution was more appropriate and this was validated by confirmatory factor analysis. This new structure also displayed strong evidence of concurrent validity when compared to the SF-36. Conclusion We recommend that researchers should submit scores obtained from items on the MacNew to secondary analyses after being grouped according to the factor structure proposed in this paper, in order to explore further the most appropriate grouping of items.

Computer usage and the validity of self-assessed computer competence among first-year business students

Abstract This study evaluates the reliability of self-assessment as a measure of computer competence. This evaluation is carried out in response to recent research which has employed self-reported ratings as the sole indicator of students’ computer competence. To evaluate the reliability of self-assessed computer competence, the scores achieved by students in self-assessed computer competence tests are compared with scores achieved in objective tests. The results reveal a statistically significantly over-estimation of computer competence among the students surveyed. Furthermore, reported pre-university computer experience in terms of home and school use and formal IT education does not affect this result. The findings call into question the validity of using self-assessment as a measure of computer competence. More generally, the study also provides an up-to-date picture of self-reported computer usage and IT experience among pre-university students from New Zealand and South-east Asia and contrasts these findings with those from previous research.

Validity, trustworthiness and rigour:reasserting realism in qualitative research

Aim The aim of this paper is to challenge recent sceptical approaches to the possibility of validating qualitative research and to underline the benefits of adopting a realist approach to validity. Background In recent discussion about the methodological bases for qualitative research it has been argued that, because different methodologies take different approaches to validity, attempts to develop a common set of validation criteria are futile. On the basis of this sceptical view, a number of strategies for judging qualitative research have been proposed. These include suggestions that: it should be judged according to aesthetic or rhetorical criteria, rather than epistemological validity; responsibility for appraisal should move from researchers to readers; each methodology should be assessed individually according to its own merits. Discussion None of these suggestions provide a viable alternative to validity, defined as the extent to which research reflects accurately that to which it refers. Because the form of research does not determine its content, replacement of epistemology by aesthetics is unsustainable. Because research reports mediate between writer and reader, a one-sided approach to this relationship constitutes a false dichotomy. If we accept the criterion of practitioner confidence as a means of judging methodological approaches, this involves rejection of judgement according to a methodology�s own merits. Conclusion If qualitative research is actually about something, and if it is required to provide beneficial information, then a realist approach to validity holds out greatest promise.

The validity of a latent class typology of adolescent drinking patterns

Objectives: This study examined the validity of a latent class typology of adolescent drinking based on four alcohol dimensions; frequency of drinking, quantity consumed, frequency of binge drinking and the number of alcohol related problems encountered. Method: Data used were from the 1970 British Cohort Study sixteen-year-old follow-up. Partial or complete responses to the selected alcohol measures were provided by 6,516 cohort members. The data were collected via a series of postal questionnaires. Results: A five class LCA typology was constructed. Around 12% of the sample were classified as �hazardous drinkers� reporting frequent drinking, high levels of alcohol consumed, frequent binge drinking and multiple alcohol related problems. Multinomial logistic regression, with multiple imputation for missing data, was used to assess the covariates of adolescent drinking patterns. Hazardous drinking was associated with being white, being male, having heavy drinking parents (in particular fathers), smoking, illicit drug use, and minor and violent offending behaviour. Non-significant associations were found between drinking patterns and general mental health and attention deficient disorder. Conclusion: The latent class typology exhibited concurrent validity in terms of its ability to distinguish respondents across a number of alcohol and non-alcohol indicators. Notwithstanding a number of limitations, latent class analysis offers an alternative data reduction method for the construction of drinking typologies that addresses known weaknesses inherent in more tradition classification methods.

Validity of the Perceived Health Competence Scale in a UK primary care setting.

The Perceived Health Competence Scale (PHCS) is a measure of self-efficacy regarding general healthrelated behaviour. This brief paper examines the psychometric properties of the PHCS in a UK context. Questionnaires containing the PHCS, the SF-36 and questions about perceived health needs were posted to 486 patients randomly selected from a GP practice list. Complete questionnaires were returned by 320 patients. Analyses of these responses provide strong evidence for the validity of the PHCS in this setting. Consequently, we conclude that the PHCS is a useful addition to measures of global self-efficacy and measures of self-efficacy regarding specific behaviours in the toolkit of health psychologists. This range of self-efficacy assessment tools will ensure that psychologists can match the level of specificity of the measure of expectancy beliefs to the level of specificity of the outcome of interest.

Reliability and Validity of the Child Health QuestionnairePF-50 for European Children with Cerebral Palsy

Objective: To evaluate the psychometric performance of the Child Health Questionnaire (CHQ) in children with cerebral palsy (CP).
Method: 818 parents of children with CP, aged 8–12 from nine regions of Europe completed the CHQ (parent form 50 items). Functional abilities were classified using the five-level Gross Motor Function Classification Scheme (Levels I–III as ambulant; Level IV–V as nonambulant CP).
Results: Ceiling effects were observed for a number of subscales and summary scores across all Gross Motor Function Classification System levels, whilst floor effects occurred only in the physical functioning scale (Level V CP). Reliability was satisfactory overall. Confirmatory factor analysis (CFA) revealed a seven-factor structure for the total sample of children with CP but with different factor structures for ambulant and nonambulant children.
Conclusion: The CHQ has limited applicability in children with CP, although with judicious use of certain domains for ambulant and nonambulant children can provide useful and comparable data about child health status for descriptive purposes.

Validity and reliability of cardiorespiratory measurements recorded by the LifeShirt during exercise tests

The LifeShirt is a novel ambulatory monitoring system that records cardio respiratory measurements outside the laboratory. Validity and reliability of cardiorespiratory measurements recorded by the LifeShirt were assessed and two methods of calibrating the LifeShirt were compared. Participants performed an incremental treadmill test and a constant work rate test (65% peak oxygen uptake) on four occasions (>48 In apart) and wore the LifeShirt, COSMED system and Polar Sport Tester simultaneously. The LifeShirt was calibrated using two methods: comparison to a spirometer; and 800 ml fixed-volume bag. Ventilation, respiratory rate, expiratory time and heart rate recorded by the LifeShirt were compared to measurements recorded by laboratory equipment. Sixteen adults participated (6M: 10F); mean (SD) age 23.1 (2.9) years. Agreement between the LifeShirt and laboratory equipment was acceptable. Agreement for ventilation was improved by calibrating the LifeShirt using a spirometer. Reliability was similar for the LifeShirt and the laboratory equipment. This study suggests that the LifeShirt provides a valid and reliable method of ambulatory monitoring. (C) 2009 Elsevier B.V. All rights reserved.