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PubMed2003

The quality of clinical trials with Harpagophytum procumbens.

OBJECTIVE: To examine systematically the quality of the clinical trials investigating the effectiveness of Harpagophytum products. METHODS: Literature searches and enquiries to experts identified 20 studies of treatment with various Harpagophytum products (powder, aqueous and ethanolic extracts) for exacerbations of chronic musculoskeletal pain. Eight were open uncontrolled observational studies, one comparing progress under treatment for pain in back, knee and hip pain. Two were open comparisons with conventional treatment, only one of which was randomised. Ten were double-blinded, randomised controlled comparisons, 8 with placebo and 2 with NSAID comparator treatments. Indices of the internal and external validities were examined by reference to a checklist to see how well the studies answered the questions: do Harpagophytum products work and do they work as well as more conventional comparator treatments? RESULTS: The uncontrolled trials, though providing useful preliminary estimates of the possible effect of treating various conditions, could not separate the effects of the Harpagophytum product from whatever placebo effect might have been exerted in the circumstances of the study. The 2 open comparisons were open to performance, detection and/or selection bias. Of the 8 randomised double blinded controlled comparisons with placebo, 6 were marred by lack of transparency, one could not provide definitive evidence from its pre-selected principal outcome measure, and one provided good quality evidence of a dose dependent superiority of effect over placebo, though this was with a product that is not generally available for clinical practice. One of the randomised controlled comparisons with comparator (Doloteffin versus rofecoxib) was intended only as a pilot and studied too few patients for definitive conclusions whereas the other did provide good evidence that the powder, Harpadol is not importantly less effective than the weak NSAID diacerhein. CONCLUSIONS: Evidence of effectiveness of Harpagophytum products is not transferrable from product to product. The results of some studies suggest some effectiveness for some products, but for none of the clinically available products is the quality of evidence totally satisfactory. It is better so far with products that contain at least 50 mg of harpagoside in the daily dosage than with products (which happen to be of ethanolic extraction) that contain less.

Harpagophytum↗

PubMed2006

The effect of joystick handle size and gain at two levels of required precision on performance and physical load on crane operators.

The study was designed to determine the effect of joystick handle size and (display-control) gain at two levels of required task precision on performance and physical load on crane operators. Eight experienced crane operators performed a simulated crane operation task on a computer by use of a joystick with either a short or a large handle. The task was performed at three gain levels and at two levels of required precision. Task performance, wrist and forearm postures, upper extremity muscle activity, perceived exertion and perceived comfort were measured.Task performance improved when using the joystick with the short handle and when working at a higher gain, while physical load decreased or remained the same. An increased level of required task precision was associated with a lower performance, but physical load was not affected. External validity of the simulated crane task seemed sufficient enough to extrapolate the results to practice.A joystick with a short handle is recommended, as this leads to an increased performance whilst the operator's physical load decreases or remains the same. Further optimization of performance and physical load can be achieved by optimizing gain settings of the joystick in relation to the task and type of joystick used.

Adult↗

PubMed2003

Utility analysis for clinical decision-making in small treatment settings.

Data-driven clinical decision-making can be difficult in settings that service relatively few patients because of the small samples available, the patients' potential dissimilarity from participants in published research, and highly limited resources. This study was designed to demonstrate how utility analyses might assist clinical decision-making in small treatment settings and provide data for promoting programmatic improvements. Data came from a study to identify rural juvenile delinquents suspected to not benefit from residential behavioral treatment. A prospective correlational design was used with data from a midwestern juvenile criminal justice residential unit in which about 30 males were treated annually. Outcomes included treatment performance measures and number of delinquent offenses during the year after treatment. Utility analyses suggested that delinquents who were less likely to benefit from residential treatment could be identified a priori using a modified Psychopathy Checklist, Revised. Cost utility analysis estimated $180,000 less would be spent on residential treatment as a result of selecting residents based on the pretreatment assessment. This money might be reallocated toward alternative intervention for delinquents who are not likely to benefit from the residential treatment. More importantly, results suggested specific alternative interventions for the delinquents who were less likely to benefit from the treatment by providing direct links to existing literature. Advantages of utility analysis research include strong external validity, minimal interference with treatment during data collection, results that estimate clinical and practical significance, and results that are easily communicated to laymen.

Adolescent↗

PubMed1980

Lateralized hand gesture during speech.

A group of individuals conversing in natural dyads and a group of lecturers were observed for lateral hand movement patterns during speech. Right-handed individuals in both groups displayed a significant right hand bias for gesture movements but no lateral bias for self-touching movements. The study provides external validity for previous laboratory studies of lateralized hand gesture. The results were interpreted as evidence of a central processor for both spoken and gestural communication.

Journal Article↗

PubMed1984

Temperament differences between infants who do and do not complete laboratory testing.

Temperament differences were examined in a group of 24 Caucasian infants classified as completers (n = 16) and noncompleters (n = 8) on the basis of their performance in a visual habituation study. Maternal ratings of infant temperament based upon the Infant Temperament Questionnaire Revised revealed that noncompleters, in comparison with completers, were found to be more: arrhythmic, withdrawing, and intense, and less distractible. A composite measure of difficultness found the completers more likely to be classified as "easy" while the noncompleters were often classified as "difficult" babies. The findings suggest that to increase the external validity of infant research it may be beneficial to include more exact descriptions both of Ss who complete and those who fail to complete experiments.

Cognition↗

PubMed1995

Stoicism: its relation to gender, attitudes toward poverty, and reactions to emotive material.

A scale was developed to test the hypotheses that stoicism would be more prevalent in British men (n = 30) than in British women (n = 32) and that stoicism would be related to negative attitudes toward the poor. It was also hypothesized that stoics would exhibit a weaker emotional reaction to stories that had emotive content. All three hypotheses were supported. There was evidence that the Stoicism Scale had internal consistency and some external validity.

Adult↗

PubMed1997

A field trial of the effectiveness of behavioral treatment for sexual dysfunctions.

The present study was a field trial of behavioral sex therapy for 365 married couples presenting with a range of sexual dysfunctions. Treatment occurred at an outpatient sexual dysfunction clinic of a large medical center using a multidisciplinary staff. Findings supported the external validity of behavioral sex therapy. The success rate for the total sample (65%) was comparable to that of previous investigations, and there were very few dropouts (1.6%) from treatment. In addition, outcomes did not vary significantly as a function of diagnoses, gender, or a history of sexual abuse. The amount of sensate focus completed in the last week of treatment was the strongest predictor of successful treatment. For some diagnoses, however, couple comorbidity reduced treatment success. Results indicated that behavioral sex therapy is effective in real-world clinical settings.

Adult↗

PubMed1997

Therapeutic and iatrogenic interventions with adults who were sexually abused as children.

The field of sexual victimization and trauma has generated incompatible paradigms that confuse conceptualization, assessment, and treatment for adult survivors of child sexual abuse. It is crucial to be aware of potential iatrogenic concepts and interventions, especially those involving litigation, obscessing about past trauma, self-esteem as a victim, quest for external validation, identification with the victim movement, exploration of repressed memories as a goal in itself, and focus on the past at the expense of being a survivor in the present. Core therapeutic concepts are accepting oneself as a survivor; experiencing adult sexuality as voluntary, mutual, and pleasure-oriented, and feeling deserving of healthy sexuality; and focusing on living well in personal, sexual, marital, and parenting roles.

Adult↗

PubMed1986

Developmental classification of reading-disabled children.

The present study developed and used longitudinal cluster analysis, a multivariate classification technique, to classify a sample of 200 nonclinical normal and reading-disabled males based on their performances on a neuropsychological battery at kindergarten, second, and fifth grades. The resulting classification was examined against various internal and external validation criteria. Using a validation framework, five developmental subtypes of children, two normal and three deficit reader groups, were found. Three of these groups could best be described as partitions of a multivariate normal distribution; the other two, both containing deficit readers, showed different covariance structures, suggesting differing developmental patterns. These groups were shown to differ with respect to the domains of academic achievement, parental achievement, neurological status, birth histories, school behaviors, and neuropsychological-cognitive development. The results suggest that developmental classifications can be formed by using multivariate classification methods and the subtypes support findings from cross-sectional classification research on similar populations.

Child↗

PubMed1992

Electrophysiological evidence of lateralized disturbances in children with learning disabilities.

This study used an electrophysiological measurement operation to investigate lateralized processing deficits associated with academic learning-disability subtypes. Fast frequency EEG activity in the 36-44 hertz (Hz) band was recorded from reading-disabled (RLD), arithmetic-disabled (ALD), and nondisabled control children engaged in verbal and nonverbal cognitive tasks. The control group, but neither LD group, exhibited a task-dependent shift in lateralization of 40 Hz EEG; the RLD subjects generated proportionately less left-hemisphere 40 Hz activity than control or ALD subjects during the verbal task; and the ALD subjects generated proportionately less right-hemisphere activity than control or RLD subjects during the nonverbal task. These results indicate that lateralized processing deficits are associated with different types of disabilities, and provide external validation of learning-disability classifications based on academic performance patterns.

Adolescent↗

PubMed2001

Selected issues in the design and analysis of sport performance research.

The aim of this review is to discuss some issues in the design and statistical analysis of sport performance research, rather than to supply an authoritative 'cookbook' of methods. In general, we try to communicate some possible solutions to the conundrum of how to maintain both internal and external validity, as well as optimize statistical power, in applied sport performance research. We start by arguing that some sport performance research has been overly concerned with physiological predictors of performance, at the expense of not providing a valid and reliable description of the exact nature of the task in question. We show how the influence of certain factors on competitive performances can be described using linear or logistic regression. We discuss the choice of analysis for factorial repeated-measures designs, which is complicated by the assumption of 'sphericity' in a univariate general linear model, and the relatively low statistical power of the multivariate approach when used with small samples. We consider a little-used and simpler technique known as 'analysis of summary statistics'. In multi-group pre- and post-test designs, a useful technique can be to pair-match individuals on their performance scores in a counterbalanced fashion before the intervention or control has been introduced. Finally, we outline how confidence intervals can help in making statements about the probability of the population difference in performance exceeding the value designated as being worthwhile or not.

Humans↗

PubMed2005

Working memory period: the endurance of mental representations.

Working memory span assesses the maximum number of items that can be remembered in the face of concurrent processing. Models of working memory differ on several dimensions, yet many rely exclusively on this span procedure for their evidence. Three experiments consider an alternative paradigm that attempts to capture the endurance limits for remembering a fixed number of items during concurrent processing. Eight-year-old children performed two versions of this working memory period measure--operation period and reading period. Period scores show healthy test-retest reliability and external validity for scholastic attainment, comparing well with span scores in these respects. In addition, period is highly correlated with span and shows similar effects of varying the order in which stimuli are presented. We conclude that the durability of representations is an important factor in both span and period.

Achievement↗

PubMedDate not supplied

British growth charts for height and weight with recommendations concerning their use in auxological assessment.

PRIMARY OBJECTIVE: To review the appropriateness of current British growth charts for height and weight. METHODS AND PROCEDURES: A review of their structure and function in the context of the problems posed by (1) secular trends for increasing size, (2) the external validity of source samples, (3) differences in the design and application of cross-sectional and longitudinal charts, and (4) the clinical significance of differences between current charts. MAIN OUTCOMES AND RESULTS: Charts pre-dating the Freeman et al. 1995 and the Buckler-Tanner 1995 charts should be considered obsolete for the purposes of growth assessment on a sample or individual basis. Either the Freeman or the Buckler-Tanner chart is suitable for screening, surveillance or monitoring prior to adolescence but the Freeman chart is recommended for screening and surveillance of samples of children throughout childhood and adolescence. When comprehensive growth and development data are available it is advantageous to use the Buckler-Tanner chart during adolescence for the diagnosis and monitoring of individual children.

Adolescent↗

PubMed1990

Determining neuropsychological cut scores for older, healthy adults.

Three age groups (20-31, 37-49, and 55-67 years) of healthy men and women were compared on tests from the Halstead-Reitan neuropsychological test battery. Age-cohort differences in performance were observed for every measure (except Finger Tapping) and for overall indices of cognitive functioning, the Average Impairment Rating (AIR) and the Halstead-Reitan Impairment Index (HR II). When traditional cut scores (developed with age-heterogeneous samples) were used, alarmingly high percentages of subjects in the oldest group were defined as brain damaged. These findings were not attributable to higher levels of psychometrically-assessed anxiety and depression in the older groups or for the impaired subjects. Slightly more conservative criteria (fewer diagnoses of brain impairment) were then employed. The first, AIR greater than or equal to 2.00, resulted in a low and more reasonable base rate of brain impairment for the oldest group. The second, AIR greater than 2.00, resulted in age-parity in incidence of brain impairment. The heuristic value of more conservative AIR scores was discussed as were possible uses in applied clinical research settings. The limitations of this approach were noted with regard to its exclusive focus on the problem of false positive diagnoses. It was emphasized that, from a neuropsychological diagnostic perspective, cut scores based on healthy aging samples must ultimately be tested in the context of traditional neuropsychological studies in which external validation with neurosurgical and neurological criteria is employed.

Adult↗

PubMedDate not supplied

Content analysis: method, applications, and issues.

Content analysis research methodology is detailed, its procedures are described, some examples of its application are provided, and the controversial issues surrounding its use are discussed. Unlike strictly qualitative designs, content analysis has external validity as a goal. Because of its focus on human communication, content analysis offers practical applicability, promise, and relevance for research involving the practice and education of nurses and other helping professionals.

Humans↗

PubMed2026

Prognostic significance of NLRP-3 expression in solid cancers: a systematic review and meta-analysis.

BACKGROUND: The inflammasome is a critical immunological sensor comprised of NLRP-3, ASC, and CASPASE-1. Mutations in NLRP-3 are prevalent in inflammatory diseases. However, the role of NLRP-3 in cancer is controversial. This study investigates whether NLRP-3 expression is associated with clinical outcomes in patients with solid cancers. METHODS: PubMed (MEDLINE), Embase, Cochrane, and Google Scholar were searched for articles reporting NLRP-3 expression and disease outcome data in cancer patients. RevMan Review Manager was used to calculate pooled hazard ratios and Mantel-Haenszel pooled odds ratios. RNA sequencing datasets from the TCGA Pan-Cancer (PANCAN) were used for external validation. RESULTS: Patients with higher NLRP-3 expression showed a significant association with larger tumor size, advanced tumor grade, TNM stage, and presence of metastasis. High NLRP-3 expression has a significant association with poor OS (HR:2.12, 95% CI = 1.49-3.03), p < 0.0001) and DFS (HR:1.86, 95% CI = 1.30- 2.65, p = 0.0007). Subgroup analysis showed that higher NLRP-3 expression is associated with worse OS in head and neck cancer (HR: 2.77, 95% CI = 1.88-4.09, p < 0.00001), colorectal cancers (HR:2.14, 95% CI= 1.59- 2.87, p < 0.00001), and pancreatic cancer patients (HR: 3.19, 95% CI = 1.73-5.91, p = 0.0002). CONCLUSION: High NLRP-3 expression is associated with advanced disease and poor outcomes in many solid tumours.

Humans↗

PubMed2006

Empirically derived ability-achievement subtypes in a clinical sample.

The purpose of the present study was to identify reliable and clinically meaningful patterns of ability and achievement using the WISC-III and WIAT. Cluster analysis was used to group the 182 WISC-III and WIAT profiles (10 WISC-III subtests and 4 WIAT subtests) of children between the ages of 9 and 14 years. Theoretical and empirical considerations were used to identify a cluster solution, which involved comparison of several five-, six- and eight-cluster solutions. A five-cluster solution was selected as being representative of the data, which was well replicated across three hierarchical clustering methods (i.e., complete linkage, average linkage-within groups, and average linkage-between groups (UPGMA)). The clusters were labeled based on their most salient characteristics, which included a group of predominantly low ability and achievement, a group demonstrating a pattern of verbal processing deficits, a group demonstrating a pattern of visual spatial/processing speed deficits, a group with low ability and achievement with average processing speed, and a group with deficits consistent with an ACID pattern. The external validity of the five subtypes was assessed through an evaluation of the relationship between cluster membership and neuropsychological test data. Most predictions regarding neuropsychological performance were supported by the data, providing further evidence of the validity of the five-cluster solution. Clinical implications of the ability-achievement typology and suggestions for future research are discussed.

Achievement↗

PubMed2004

Prognostic social factors in the subacute phase after a stroke for the discharge destination from the hospital stroke-unit. A systematic review of the literature.

PURPOSE: The objective of our study was to identify prognostic social factors in the subacute phase after stroke for the discharge destination from the hospital stroke-unit. METHODS: A systematic literature search was performed, designed in accordance with the Cochrane Collaboration criteria. Internal, statistical and external validity of the studies were assessed using a checklist with 11 methodological criteria. RESULTS: Characteristics of the social situation that proved to be important for prediction of the discharge destination are marital status and social support. Quantity and methodological quality of the research studies were insufficient, and the number of possible social prognostic factors investigated was limited by the absence of a conceptual framework of social subdomains in the studies, including an unambiguous definition of the prognostic social factors within these subdomains. CONCLUSIONS: A great need exists for research into the prognostic qualities of the following social factors: the ability to provide support, presence, and readiness of the homefront; the availability of professional care, personal financial means, membership of societies and clubs, frequency of contacts with close relatives and friends; the quality of the patient's residence with regard to the adaptation to the needs and abilities of the patient. A commitment about the aforementioned conceptual framework is mandatory.

Activities of Daily Living↗