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Required steps for the validation of a Laboratory Information Management System.

The task of managing laboratory data is not a new one. Over the past two decades, the use of Laboratory Information Management Systems (LIMS) has revolutionized how laboratories manage their data. A LIMS is more than software; it has become the workhorse of the laboratory, encompassing laboratory work-flow combined with user input, data collection, instrument integration, data analysis, user notification, and delivery of information and reporting. Types of organizations that utilize LIMS vary greatly from research laboratories to manufacturing laboratories to environmental testing laboratories. Commercially-available LIMS have been around since the 1980s. In addition, many laboratories have designed, implemented, and maintained in-house LIMS. The heart of any LIMS is the software. Like other laboratory systems, the LIMS software is subject to quality control and quality assurance checks. In regulatory environments this associated QA/QC is referred to as "system validation." The primary purpose of system validation is to ensure that the software is performing in a manner for which it was designed. For example, the system acceptance criteria should be established and tested against quantifiable tasks to determine if the desired outcome has been achieved. LIMS features, such as autoreporting, reproducibility, throughput, and accuracy must be quantifiable and verifiable. System validation ensures that the entire system has been properly tested, incorporates required controls, and maintains and will continue to maintain data integrity. Laboratories must establish protocols and standards for the validation process and associated documentation. Although vendors of commercial LIMS perform initial internal system validations, the system must be revalidated whenever the end user, vendor or third party adds modifications or customizations to the LIMS. Currently, detailed guidance regarding system validation of LIMS is not available to the user. The issue is addressed in Good Automated Laboratory Practices (GALP) and National Environmental Laboratory Accreditation Conference (NELAC) documents which indicate specific requirements or recommendations for operational checks and periodic testing; however, it is up to the laboratory to determine suitable methods to accomplish these tasks. Proper validation of a LIMS will allow a laboratory to comply with regulations and also provide comprehensive documentation on the system that is necessary to troubleshoot future problems.

Clinical Laboratory Information Systems↗

Developing an instrument to measure quality of life of patients with hyperhidrosis.

Quality of life (QOL) is an index of the state of wellness of an individual. The purpose of this study was to develop an instrument to measure quality of life of patients with hyperhidrosis. With a multi- dimensional model of QOL as the conceptual framework for instrument development, the study started from literature review which was followed by interviews with patients, staff nurses, and doctors to generate the original items for the instrument. The validity and reliability then were assessed. Six experts performed content validity (CVI =.70). Internal consistency and construct validity assessment followed. A quantitative research method was used in this study. During March 2002 to April 2003, 85 patients from the surgical outpatient clinic at a teaching hospital in southern Taiwan were purposively recruifed as subjects. Written consent was obtained before subjects answered a questionnaire that should take 8-10 minutes to finish. Data analysis was performed using SPSS for Windows 8.0. Mean, standard deviation, frequency, percentage, Cronbach ' s alpha, Pearson ' s correlation, and factor analysis were used to analyze the data. Exploratory factor analysis identified five factors. They were functional, social interaction, personal affective, psychological and physical function. The coefficients of Cronbach ' s alpha for these five factors ranged from 0.71 to 0.94. These five factors explained 68.90 % of the variance in QOL among the patients with hyperhidrosis. The results showed that the instrument had satisfactory validity and reliability. Implications of these results for future studies were discussed.

Activities of Daily Living↗

Nurse competence scale: development and psychometric testing.

BACKGROUND: Self-assessment assists nurses to maintain and improve their practice by identifying their strengths and areas that may need to be further developed. Professional competence profiles encourage them to take an active part in the learning process of continuing education. Although competence recognition offers a way to motivate practising nurses to produce quality care, few measuring tools are available for this purpose. AIM: This paper describes the development and testing of the Nurse Competence Scale, an instrument with which the level of nurse competence can be assessed in different hospital work environments. METHODS: The categories of the Nurse Competence Scale were derived from Benner's From Novice to Expert competency framework. A seven-step approach, including literature review and six expert groups, was used to identify and validate the indicators of nurse competence. After a pilot test, psychometric testing of the Nurse Competence Scale (content, construct and concurrent validity, and internal consistency) was undertaken with 498 nurses. The 73-item scale consists of seven categories, with responses on a visual analogy scale format. The frequency of using competencies was additionally tested with a four-point scale. RESULTS: Self-assessed overall scores indicated a high level of competence across categories. The Nurse Competence Scale data were normally distributed. The higher the frequency of using competencies, the higher was the self-assessed level of competence. Age and length of work experience had a positive but not very strong correlation with level of competence. According to the item analysis, the categories of the Nurse Competence Scale showed good internal consistency. CONCLUSION: The results provide strong evidence of the reliability and validity of the Nurse Competence Scale.

Adult↗

Coronary revascularisation outcome questionnaire (CROQ): development and validation of a new, patient based measure of outcome in coronary bypass surgery and angioplasty.

OBJECTIVE: To describe the development and scientific validation of a new patient based measure, the coronary revascularisation outcome questionnaire (CROQ), to evaluate health outcomes and quality of life before and after coronary artery bypass grafting and percutaneous transluminal coronary angioplasty. DESIGN AND SETTING: Psychometric validation study conducted with patients from three hospitals in the UK. PATIENTS: Two independent field tests were conducted by postal survey of 714 patients before and 1329 patients after coronary revascularisation to evaluate the measurement properties of the CROQ. METHODS: Qualitative methods including patient interviews were used to develop questionnaire content. A full psychometric evaluation was performed on the survey data. RESULTS: Psychometric tests with the application of stringent criteria confirmed the acceptability (low missing data, good response rates), scaling assumptions (good item convergent and discriminant validity), reliability (good internal consistency and reproducibility), validity (good content and construct validity), and responsiveness of the CROQ. CONCLUSIONS: The CROQ is a practical and scientifically sound patient based measure of outcome developed using psychometric methods. It captures aspects of recovery not addressed in other cardiac questionnaires and has been shown to be a highly responsive instrument that will be useful in evaluating outcomes in clinical trials.

Adult↗

Measuring safety climate in health care.

AIM: To review quantitative studies of safety climate in health care to examine the psychometric properties of the questionnaires designed to measure this construct. METHOD: A systematic literature review was undertaken to study sample and questionnaire design characteristics (source, no of items, scale type), construct validity (content validity, factor structure and internal reliability, concurrent validity), within group agreement, and level of analysis. RESULTS: Twelve studies were examined. There was a lack of explicit theoretical underpinning for most questionnaires and some instruments did not report standard psychometric criteria. Where this information was available, several questionnaires appeared to have limitations. CONCLUSIONS: More consideration should be given to psychometric factors in the design of healthcare safety climate instruments, especially as these are beginning to be used in large scale surveys across healthcare organisations.

Attitude of Health Personnel↗

Quantification of residual disease in chronic myelogenous leukemia patients on interferon-alpha therapy by competitive polymerase chain reaction.

Interferon-alpha (IFN-alpha) induces cytogenetic responses of variable degree in patients with chronic myelogenous leukemia (CML). We sought to establish the relationship between BCR-ABL transcript numbers measured by competitive 2-step reverse transcription polymerase chain reaction (RT-PCR) and cytogenetic status in CML patients treated with IFN-alpha. A total of 250 peripheral blood and 55 bone marrow samples with 127 Philadelphia chromosome positive (Ph+) and 6 Ph-/BCR-ABL+ CML patients were investigated. Twenty-one patients were studied at diagnosis with IFN-alpha, 24 had a complete cytogenetic response, 21 a partial response, 12 a minor response, 26 no response, and 23 were unknown. Using nested RT-PCR, all 305 samples were positive for BCR-ABL transcripts. To standardize results for variability in RNA and cDNA quantity and quality, we quantified total ABL transcripts in each sample as internal control. The validity of ABL as internal control was shown by comparison with glucose-6-phosphate dehydrogenase transcript levels in 145 samples. The median BCR-ABL transcript numbers (and BCR-ABL/ABL ratios expressed as percentages) were 400/micrograms RNA (O.04%) in complete responders, 20,500/micrograms RNA (7.1%) in partial responders, 170,000/micrograms RNA (21.0%) in minor responders, and 430,000/micrograms RNA (58.7%) in nonresponders (P < .001). The cytogenetic results correlated with the BCR-ABL transcript numbers (r = .82; P < .001) and BCR-ABL/ABL ratios (r = .84; P < .001). Grouping the ratios BCR-ABL/ABL as less than 2%, 2% to 14% and greater than 14% to compare with cytogenetic complete response, partial response, and minor/nonresponse, the concordance between the two methods was 82% (chi2 P< .0001). We conclude that quantitative PCR with internal controls is as sensitive and reliable method for monitoring patients on IFN-alpha and reduces the need for repeated marrow investigations.

Adolescent↗

WOMAC osteoarthritis index. Reliability, validity, and responsiveness in patients with arthroscopically assessed osteoarthritis. Western Ontario and MacMaster Universities.

OBJECTIVE: To validate the WOMAC Osteoarthritis Index for use in Sweden. METHODS: Test-retest reliability, internal consistency, validity, and responsiveness was determined in 52 patients (mean age 48 (20-69)) with arthroscopically assessed cartilage damage of the tibio-femoral knee joint. RESULTS: All WOMAC scales were internally consistent with Cronbach's alpha coefficients of 0.83, 0.87, and 0.96 pre-operatively. Test-retest reliability was satisfactory with intraclass correlation coefficients of 0.74, 0.58, and 0.92. As hypothesized worse post-operative but not pre-operative outcomes were associated with radiographic OA. In comparison with the SF-36 the expected correlations were found when comparing items measuring similar and dissimilar constructs, supporting the concepts of convergent and divergent construct validity. Three months after arthroscopy significant mean improvement was seen in all WOMAC scales (p<0.0004). CONCLUSION: The Swedish version of WOMAC is a reliable, valid, and responsive instrument with metric properties in agreement with the original widely used version.

Adult↗

Reliability and validity studies of the WHO--Composite International Diagnostic Interview (CIDI): a critical review.

This paper reviews reliability and validity studies of the WHO - Composite International Diagnostic Interview (CIDI). The CIDI is a comprehensive and fully standardized diagnostic interview designed for assessing mental disorders according to the definitions of the Diagnostic Criteria for Research of ICD-10 and DSM-III-R. The instrument contains 276 symptom questions many of which are coupled with probe questions to evaluate symptom severity, as well as questions for assessing help-seeking behavior, psychosocial impairments, and other episode-related questions. Although primarily intended for use in epidemiological studies of mental disorders, it is also being used extensively for clinical and other research purposes. The review documents the wide spread use of the instrument and discusses several test-retest and interrater reliability studies of the CIDI. Both types of studies have confirmed good to excellent Kappa coefficients for most diagnostic sections. In international multicenter studies as well as several smaller center studies the CIDI was judged to be acceptable for most subjects and was found to be appropriate for use in different kinds of settings and countries. There is however still a need for reliability studies in general population samples, the area the CIDI was primary intended for. Only a few selected aspects of validity have been examined so far, mostly in smaller selected clinical samples. The need for further procedural validity studies of the CIDI with clinical instruments such as the SCAN as well as cognitive validation studies is emphasized. The latter should focus on specific aspects, such as the use of standardized questions in the elderly, cognitive probes to improve recall of episodes and their timing, as well as the role of order effects in the presentation of diagnostic sections.

Cross-Cultural Comparison↗

Evaluation of depression in schizophrenia: psychometric properties of a French version of the Calgary Depression Scale.

The aim of this study was to determine the psychometric properties (especially validity and reliability) of the French language version of the Calgary Depression Scale for Schizophrenia (CDSS) in schizophrenic patients. Ninety-five subjects who met DSM-IV criteria for schizophrenia were enrolled. The studies of the internal structural validity and of the reliability (internal consistency) showed that some items from the CDSS (early awakening and guilty ideas of reference) must be discussed in the constitution of this scale. The total score of the CDSS was significantly correlated with the MADRS total score, the HDRS total score, and the depression item (G6) on the PANSS, which suggests that the CDSS is a valid instrument for the assessment of depression in schizophrenia. The existence of a significant correlation between the CDSS total score and the PANSS positive sub-scale suggests a possible relationship between positive and depressive symptoms in schizophrenia.

Adult↗

Measuring the information needs of husbands of women with breast cancer: validity and reliability of the Family Inventory of Needs--husbands.

PURPOSE/OBJECTIVES: A two-phase study was undertaken to test the Family Inventory of Needs--Husbands (FIN-H), a tool designed to measure the information needs of husbands of women with breast cancer and the extent to which these needs are met. DESIGN: Methodologic survey. SAMPLES: Phase I: a panel of 6 husbands; phase II: 84 husbands of women with breast cancer. METHODS: Panel of expert ratings followed by pilot test of the two-part survey. FINDINGS: In phase I, husbands assessed the FIN-H for clarity, internal consistency, and content validity. All preset criteria were met. In phase II, internal consistency, test-retest reliability, and internal validity were assessed. Internal consistency estimates as measured by Cronbach's standardized alpha coefficients were 0.91 and 0.93. Test-retest correlations were 0.82 and 0.76 (p = 0.0001). Exploratory factor analysis suggested that the FIN-H consists of five factors. CONCLUSIONS: Initial results suggest that the FIN-H is reliable and valid. Further testing is needed to confirm these results. IMPLICATIONS FOR NURSING PRACTICE: Before nurses can address the information needs of husbands of women with breast cancer, use of a reliable and valid assessment tool is recommended.

Adult↗

Establishing the psychometric properties of the DSM-III-R personality disorders: implications for DSM-V.

In this study, symptom (item) level data were used to perform a psychometric analysis of the DSM-III-R personality disorders (PDs). Determined for each PD criteria set were convergent validity, discriminant validity, and internal consistency. The results indicated that the majority of the PD criteria sets (6 of the 11 ) possessed adequate convergent validity, although discriminant validity was problematic for most of these disorders. Internal consistency was also weak for the PD criteria sets, with only 3 of the 11 exceeding a minimum cutoff score of .70. The present study employed a methodology modeled after the one reported by Morey (1988a), and the results of the two studies were highly similar. Consistent findings across the two data sets can be taken to reflect the actual psychometric properties of the DSM-III-R PDs. The success of our replication demonstrates the potential that large-scale psychometric investigations hold for aiding the development and refinement of the DSM PDs.

Humans↗

The performance properties of the International Index of Erectile Function (IIEF-15) in assessing erectile dysfunction in patients with lower urinary tract symptoms.

To validate the International Index of Erectile Function (IIEF-15) in Malaysian population. Reliability and internal consistency were evaluated using the test-retest method and Cronbach's alpha. Sensitivity to change was expressed as the effect size index. Internal consistency was excellent (Cronbach's alpha value = 0.75 to 0.90) Test-retest correlation coefficient and intraclass correlation coefficient were highly significant (ICC = 0.75 and above) and a high degree of sensitivity and specificity was observed. The IIEF-15 is suitable, reliable, valid and sensitive to clinical change in the Malaysian population.

Aged↗

Satisfactory cross cultural equivalence of the Dutch WOMAC in patients with hip osteoarthritis waiting for arthroplasty.

BACKGROUND: Cross cultural validity is of vital importance for international comparisons. OBJECTIVE: To investigate the validity of international Dutch-English comparisons when using the Dutch translation of the Western Ontario and McMaster Universities osteoarthritis index (WOMAC). PATIENTS AND METHODS: The dimensionality, reliability, construct validity, and cross cultural equivalence of the Dutch WOMAC in Dutch and Canadian patients waiting for primary total hip arthroplasty was investigated. Unidimensionality and cross cultural equivalence was quantified by principal component and Rasch analysis. Intratest reliability was quantified with Cronbach's alpha, and test-retest reliability with the intraclass correlation coefficient. Construct validity was quantified by correlating sum scores of the Dutch WOMAC, Arthritis Impact Measurement Scales (Dutch AIMS2), Health Assessment Questionnaire (Dutch HAQ), and Harris Hip Score (Dutch HHS). RESULTS: The WOMAC was completed by 180 Dutch and 244 English speaking Canadian patients. Unidimensionality of the Dutch WOMAC was confirmed by principal component and Rasch analysis (good fit for 20/22 items). The intratest reliability of the Dutch WOMAC for pain and physical functioning was 0.88 and 0.96, whereas the test-retest reliability was 0.77 and 0.92, respectively. Dutch WOMAC pain sum score correlated 0.69 with Dutch HAQ pain, and 0.39 with Dutch HHS pain. Dutch WOMAC physical functioning sum score correlated 0.46 with Dutch AIMS2 mobility, 0.62 with Dutch AIMS2 walking and bending, 0.67 with Dutch HAQ disability, and 0.49 with Dutch HHS function. Differential item functioning (DIF) was shown for 6/22 Dutch items. CONCLUSIONS: The Dutch WOMAC permits valid international Dutch-English comparisons after correction for DIF.

Aged↗

The ComFor: an instrument for the indication of augmentative communication in people with autism and intellectual disability.

BACKGROUND: The ComFor (Forerunners in Communication) is an instrument to explore underlying competence for augmentative communication. More specifically, it measures perception and sense-making of non-transient forms of communication at the levels of presentation and representation. The target group consists primarily of individuals with autism and intellectual disability (ID) without or with only limited verbal communication. The ComFor is suitable for children and adults with a developmental level between 12 and 60 months. This paper describes the theoretical framework and structure of the ComFor, the results of a study on its psychometric properties and its clinical uses. METHOD: The ComFor was tested on a sample of 623 children and adults from the Netherlands and Flanders: a group with autism and ID (n = 310); a group with ID without autism (n = 174); and a control group of typically developing children (n = 139). RESULTS: The data generally support the reliability and validity of the ComFor. Internal consistency, inter-rater and test-retest reliability were found to be good. Construct validity (internal structure, convergent and divergent patterns) was established in different ways. The criterion-related validity has yet to be established, as predictive data are not available at the moment. CONCLUSION: Taken together, the results indicate that the ComFor is a promising instrument to explore underlying competence for augmentative communication. Areas for future research are outlined and the clinical relevance is discussed.

Adolescent↗

Psychometric properties of the World Health Organization quality of life instrument (WHOQoL-BREF) in alcoholic males: a pilot study.

OBJECTIVE: To evaluate criterion convergent and discriminant validity of the World Health Organization Instrument (WHOQoL-BREF) in evaluating quality of life and to verify its convergent validity with the Medical Outcomes study Short-forms (SF-36) and the Symptom Check List (SCL-90) instruments in male alcohol dependent patients who seek treatment at two Brazilian treatment centers. METHODS: A cross-sectional study was performed, in which cases were divided in to two groups according to the severity of alcohol dependence, ascertained by the Short Form Alcohol Dependence Data scale (SADD). RESULTS: The sample was comprised of 36 males, and 63.9% had severe dependence. Subjects with low/moderate dependence showed higher scores in all domains of the WHOQoL-BREF and in nearly all domains of the SF-36. Criterion validity and internal consistency in the WHOQoL-BREF were satisfactory. With regard to convergent validity between the WHOQoL-BREF and SF-36, most correlation coefficients were significant. CONCLUSIONS: The WHOQoL instrument proved to be satisfactory for evaluating quality of life in this sample.

Adult↗

Motor recovery after stroke: a systematic review of the literature.

OBJECTIVE: To collect and integrate existing data concerning the occurrence, extent, time course, and prognostic determinants of motor recovery after stroke using a systematic methodologic approach. DATA SOURCES: A computer-aided search in bibliographic databases was done of longitudinal cohort studies, original prognostic studies, and randomized controlled trials published in the period 1966 to November 2001, which was expanded by references from retrieved articles and narrative reviews. STUDY SELECTION: After a preliminary screening, internal, external, and statistical validity was assessed by a priori methodologic criteria, with special emphasis on the internal validity. DATA EXTRACTION: The studies finally selected were discussed, based on the quantitative analysis of the outcome measures and prognostic determinants. Meta-analysis was pursued, but was not possible because of substantial heterogeneity. DATA SYNTHESIS: The search resulted in 174 potentially relevant studies, of which 80 passed the preliminary screening and were subjected to further methodologic assessment; 14 studies were finally selected. Approximately 65% of the hospitalized stroke survivors with initial motor deficits of the lower extremity showed some degree of motor recovery. In the case of paralysis, complete motor recovery occurred in less than 15% of the patients, both for the upper and lower extremities. Hospitalized patients with small lacunar strokes showed relatively good motor recovery. The recovery period in patients with severe stroke was twice as long as in patients with mild stroke. The initial grade of paresis was the most important predictor for motor recovery (odds ratios [OR], >4). Objective analysis of the motor pathways by motor-evoked potentials (MEPs) showed even higher ORs (ORs, >20). CONCLUSIONS: Our knowledge of motor recovery after stroke in more accurate, quantitative, and qualitive terms is still limited. Nevertheless, our data synthesis and quantitative analysis comprises data from many methodologically robust studies, which may support the clinician in the management of stroke patients. With respect to early prognosis of motor recovery, our review confirms clinical experience that the initial grade of paresis (as measured on admission in the hospital) is the most important predictor, although the accuracy of prediction rapidly improves during the first few days after stroke. Initial paralysis implies the worst prognosis for subsequent motor recovery. Remarkably, the prognostic accuracy of MEPs appears much higher than that of clinical examination for different subgroups of patients.

Activities of Daily Living↗

Development and testing of the caregiver reciprocity scale.

The purpose of this study was to develop and validate the dimensions of caregiver reciprocity. Social exchange and equity theory served as a conceptual framework for examining recprocal intergenerational exchanges of assistance and support. In the first phase of the study, 12 caregivers of elderly parents, including in-laws, were interviewed to provide narrative data from which items were developed. Content validity was judged by two separate panels of experts. The revised CRS was tested with 303 adult children for reliability and validity, including internal consistency, test-retest reliability, exploratory factor analysis, and convergent and discriminant validity testing using structural equation modeling. Support for construct validity was demonstrated for four factors: Warmth and Regard, Intrinsic Rewards of Giving, Love and Affection, and Balance within Family Caregiving.

Aged↗

[Using "Care Note" to measure the level of satisfaction patients feel with their care, in palliative cancer care, as a measure of their quality of life].

In this study, a new Questionnaire, "Care Note", was developed for palliative cancer care and it was validated in relation to the level of satisfaction in their daily lives felt by patients during supportive care. Care Note and EORTC QLQ-C 30 were administered to 97 patients with various forms of malignant disease (mean age 61, M/F 73/24). They filled in a Care Note questionnaire twice a week, on average they completed 6.77 questionnaires (a total of 657 questionnaires). The average time to answer was 5.49 minutes, and patients compliance was good. Evaluation indices in the first examination (n = 97) were shown as: content validity, test-retest reliability, item-scale correlation revealed discriminant validity and convergent validity with internal consistency, using Cronbach in the range alpha = 0.695-0.814, were proved. Concurrent validity with EORTC QLQ-C 30 was satisfied. A multiple regression analysis showed that social well-being (p < 0.0001) and global quality of life (p = 0.0001) were explanatory valuables for expressing satisfaction in relation to daily life.

Adult↗