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PubMed2004

Methodological concerns when designing trials for the efficacy of acupuncture for the treatment of pain.

The aim of all clinical research must surely be to assess an intervention or process or relationship between variables, ultimately in order to be able to improve clinical practice and healthcare for patients/consumers. As such, evidence gathered must have external validity (generalisability) and it must be relevant to clinical practice. It can be seen therefore that research into acupuncture for pain relief is an inherently difficult task, which requires much sensitivity and careful planning in order to minimise error when drawing conclusions. The researcher needs to adequately address problems such as sample size, blinding, randomisation and appropriate use of control and treatment. It is also most important to be able to clarify that the placebo (if used) is credible to the patient. The field of acupuncture has been overwhelmed with hundreds of sub-standard trials and much doubt still surrounds the issue of efficacy. Few good quality rigorous trials exist to support the use of acupuncture for pain relief in general. It has also been noted that the question of long-term efficacy has not been assessed by the many trials and this needs to be addressed prior to its acceptance. Further well conducted rigorous trials are therefore needed, utilising the lessons learnt through the substantial number of previous trials, in order to adequately assess the efficacy of acupuncture for painful conditions. Such trials must therefore: Utilise a placebo control. Be randomised and stratified. Ensure patient blinding. Use self completed outcome measures and blinded assessors. Have sufficient and well validated outcome measures. Check credibility of treatment. Have a well defined entry criteria which includes a single condition only. Have a long term follow up. Enrol sufficient subjects, the number to be determined by a power calculation. Provide adequate acupuncture treatment as would be found in clinical practice. Be group comparative so as to negate any carry-over effects. In this way good quality trials can be undertaken which will yield reliable results and therefore add meaningful data to the body of knowledge appertaining to the effectiveness of acupuncture.

Acupuncture↗
PubMed1993

Correspondence between statistically derived behavior problem syndromes and child psychiatric diagnoses in a community sample.

The correspondence between Diagnostic and Statistical Manual (3rd ed.) (DSM-III) diagnoses and statistically derived syndromes was examined within a community sample of children and adolescents in Puerto Rico. Specifically, the extent to which behavior dimensions, derived from the Child Behavior Checklist and the Youth Self-Report, corresponded to psychiatric diagnoses, derived from parent and child versions of the Diagnostic Interview Schedule for Children, was examined. The alternative approaches for assessing psychopathology in children and adolescents were compared against external validators. The results indicated a meaningful convergence between DSM-III diagnoses and statistical syndromes; however, a one-to-one correspondence did not emerge. Little evidence was found for "diagnostic thresholds." There was no evidence of the superiority of either the statistically derived syndromes or the DSM-III diagnoses. The incorporation of a measure of impairment improved the validity of both approaches. Adding parental reports to the self-reports of adolescents yielded little gain in the validity of either the statistical or diagnostic approach. The implications for the definition and assessment of child and adolescent disorders are discussed.

Adolescent↗
PubMed1992

Is Rett syndrome a subtype of pervasive developmental disorders?

The author reviews the issue on whether Rett syndrome (RS) is a subtype of pervasive developmental disorders (PDDs). More than 200 articles of RS have been published in the last 10 years. Internal and external validities of RS have been established by several independent studies. There remains the question whether RS presents clinical features that meet the total criteria for PDDs. The available data seem to support the idea of classifying RS as a subtype of PDDs in the DSM-IV.

Child↗
PubMed1983

Volunteer bias in research employing vaginal measures of sexual arousal.

Demographic, sexual, and personality characteristics of volunteers and nonvolunteers for a laboratory study of sexual arousal were compared. Subjects were 296 female students from an introductory psychology course who had volunteered for a study on sexuality and personality. After completing several questionnaires, subjects were presented with a written description of an experiment that involved viewing sexually explicit videotapes and measurement of sexual arousal with a vaginal photoplethysmograph and indicated in writing whether or not they would be interested in participating in the experiment. Chi-square analyses revealed that a greater percentage of volunteers had experienced sexual trauma and that fewer women in this group reported objections to viewing sexually explicit films than nonvolunteers. A discriminant function analysis revealed that the volunteers masturbated more frequently, had more exposure to commercialized erotica materials, were exposed to these materials at an earlier age, and reported less sexual fear than nonvolunteers. Other personality, demographic, and sexual characteristics did not differ across the groups. This study demonstrates that the external validity of studies employing vaginal measures of sexual arousal is limited. Researchers must use caution when discussing the generality of findings based on genital measurement of sexual arousal.

Adult↗
PubMed1989

Psychomotor disturbances in psychiatric patients as a possible basis for new attempts at differential diagnosis and therapy. IV. Brain dysfunction during motor activation measured by EEG mapping.

In parts I-III of this series psychometric evidence was reported of a "psychotic motor syndrome" (PMS) in schizophrenic and endogenous depressed patients, which was not found in non-endogenous depressed or healthy persons. An attempt is reported to establish signs of brain dysfunction in these patient groups during motor activation, using a 16-channel EEG mapping system. "Resting" conditions after a special relaxation procedure were compared with simple and complex motor tasks (and music perception/reproduction; to be reported separately). Two measurements, at least 2 weeks apart, were obtained for each subject, in order to obtain information on the influence of drug treatment and/or psychopathological improvement on brain dysfunction. In all, 23 male and 25 female schizophrenics, 11 male and 18 female non-endogenous depressed patients (not actually mediated, i.e. drug naive or wash-out period of 1 week to 17 years), and 26 male and 37 female endogenous depressed patients (medicated with tri- or tetracyclic antidepressants and/or benzodiazepines; no lithium treatment) were compared with 22 male and 17 female control persons (i.e. total n = 179). Major findings were obtained in the delta and alpha frequency bands yielding signs of "diffuse hyperactivation" in schizophrenic and endogenous depressed patients as compared with the patterns found in healthy persons. However, since in the non-endogenous patients a (less marked) hyperactivation of various EEG parameters was also found, unspecific effects such as anxiety/arousal may have influenced the results in psychotic patients, which was to be explored further. Drug treatment tended to "normalize" the activation pattern both in schizophrenics and endogenous depressed patients. Viewing the findings on schizophrenics using neuroimaging methods [single photon emission computerized tomography-(SPECT), magnetic resonance imaging-(MRI), positron emission tomography-(PET)], these results suggest pathological brain organization connected to an impaired motor performance (evident peripherally as PMS) in schizophrenic and endogenous depressed patients. If it is possible to further "externally validate" (by SPECT/MRI/PET) EEG mapping data this method may exclusively offer the possibility of innocuous long-term follow up of brain dysfunction in psychotic patients ("brain function monitoring"). This could enable the early recognition (and early therapy) of negative symptoms. Finally, the EEG mapping findings provide further neurophysiological basis for the use of motor training programs in the additional therapy of psychiatric patients.

Adult↗
PubMedDate not supplied

Heart rate reactivity in attention deficit disorder subgroups.

Beat-to-beat heart rate (HR) was analyzed for 9 contiguous seconds in a warned reaction time (RT) paradigm. Imperative stimuli were tones of three intensity levels (55, 78, and 100 db); a visual warning signal occurred 5 sec before tone onset. Baseline and reward conditions were run. Normal controls were contrasted with three Attention Deficit Disorder (ADD) subgroups: ADD-only, ADD with hyperactivity (ADDH), ADD with hyperactivity and aggression (ADDHA). The ADD subgroups were predicted to show less deceleration in HR because of their problem sustaining readiness to respond. Significant sex x group differences in HR levels and change scores were found. Overall, girls had higher HR levels than boys and the ADD-only group (boys and girls) had lower HRs than the other ADD groups. But, the ADD-only boys had more marked deceleration to the warning signal and acceleration to the tones than the other ADD boys, whereas the ADD-only girls were no more reactive than the ADDH and ADDHA girls. Control girls had the highest HR levels and were the most reactive to stimuli. Control boys and ADD-only boys had similar HR levels and reaction patterns. ADD-only girls appear to be underaroused, whereas ADD-only boys do not. Results suggest that cardiac measures can provide external validation of disruptive and nondisruptive ADD subtypes.

Attention Deficit Disorder with Hyperactivity↗
PubMed2000

Reading a journal article.

Journal reading is an important continuing educational activity in terms of physician preference, frequency of use amount of time devoted to it and impact in changing practice. Clinicians trying to obtain information from journals face several tasks, including the need to assess both the quality and the applicability of the information found in published articles. This article describes the general principles for reading, critically, scientific papers that report clinical research results, which include establishing the kind of question that the authors were trying to answer, the type of study done, if the research design was appropriate for the question, and if it was conducted correctly. According to several available guidelines, once the reader has a clear idea of the study question it is necessary to assess the methods described by the authors in order to evaluate whether the research strategy used is likely to have errors resulting from bias and chance (random) variation. If the paper methodology seems to be adequate, the reader should proceed to determine the results of the article and their potential clinical impact. Finally, the reader must establish the extent to which the results are helpful in caring for his or her own patients, which means assessing the external validity and other related issues. The use of these strategies will improve the efficiency of readers for incorporating research results to their practice.

Education, Medical, Continuing↗
PubMed2001

Diagnosis and treatment of rapidly cycling bipolar disorder.

The conceptualization of rapidly cycling bipolar disorder remains controversial. The DSM-IV definition of rapid cycling, although very reliable, may be not sufficiently inclusive (i.e., it may exclude patients with very short episodes of very high frequency, who are very typical in terms of external validators, and are currently regarded as rapid cyclers by many researchers and clinicians). Moreover, the addition of the requirement of pole switching (i.e., at least one direct transition from one polarity of mood to the other) during the previous year may increase the prognostic and treatment response implications of the diagnosis of rapid cycling. It is commonly held that rapid cyclers are refractory to lithium prophylaxis. However, currently available research evidence suggests that lithium prophylaxis does exert an impact on the course of rapidly cycling bipolar disorder. One double-blind crossover study supports the clinical impression that the combination of at least two mood stabilizers may be needed in most rapid cyclers.

Antimanic Agents↗
PubMed1992

A prospective evaluation of the cumulative illness rating scale.

Assessment of overall physical health is an important yet little studied problem in geriatric research. The Cumulative Illness Rating Scale (CIRS) was among the first instruments that attempted to summarize the overall severity of illness based on clinical information. This study evaluated the CIRS in a prospective longitudinal study of 181 elderly (mean age +/- SD = 79 +/- 7.4) subjects undergoing comprehensive geriatric assessment in an outpatient unit. The CIRS was found to correlate negatively with activities of daily living (r = -0.49, p = 0.0001), instrumental activities of daily living (r = -0.34, p = 0.0001), patient morale (r = -0.30, p = 0.0001), and positively with days in hospital (r = 0.21, p = 0.0075) and number of medications (r = 0.31, p = 0.0001). Mean CIRS scores for subjects who died during follow-up were significantly higher than the scores for survivors (p less than 0.01). In logistic regression, CIRS was a significant predictor of death, yet it did not improve that prediction over information contained in measures of activities of daily living. In separate logistic analyses, CIRS and age predicted acute care hospital days during follow-up, while ADL or IADL predicted the use of nursing home services. Although the CIRS appears to be a reliable method of summarizing medical information and to have some external validity, in its present form it does not provide additional prognostic information.

Aged↗
PubMed2003

The Martin and Park Environmental Demands (MPED) Questionnaire: psychometric properties of a brief instrument to measure self-reported environmental demands.

BACKGROUND AND AIMS: The present study examines the usefulness of a newly developed instrument, the Martin and Park Environmental Demands (MPED) Questionnaire, to measure the level of self-reported environmental demands of day-to-day events faced by adults aged 35 to 84 years, particularly as these demands influence forgetfulness in taking medications. METHODS: The MPED has two scales including Busyness, which addresses the density or pace of daily events to which an individual attends; and Routine, addressing the predictability or routinization of events independent of density. The MPED was administered to a sample of 121 rheumatoid arthritis patients, along with a baseline assessment battery measuring age, education, employment status, household size and other factors that might influence self-perception of Busyness and Routine. RESULTS: The scale showed good internal consistency and external validity. Higher levels of environmental demand were negatively correlated with age and positively correlated with employment, household size and medication-taking errors. There was a significant independent association between Busyness and adherence errors even after controlling for the effects of these sociodemographic variables. CONCLUSIONS: The MPED is recommended when trying to assess the general daily level of environmental demands.

Adult↗
PubMed2001

[Selection of subjects: a problem of clinical trials in traumatology. Selection effects and the problem of representation as exemplified by a prospective randomized trial on whiplash injuries].

INTRODUCTION: The internal and external validity of studies is endangered by many factors, such as selection of subjects for inclusion. Selection bias itself is a major problem, but remains unmentioned and probably unexamined in the majority of published clinical trials in traumatology. AIM OF THE STUDY: The aim of this investigation was to detect effects of subject selection which occurred during our own prospective intervention study. The clinical trial compared subjects with whiplash injury who were either treated by early mobilization or immobilization (soft collar). MATERIAL AND METHODS: Source population, eligible subjects, study participants and final study participants were compared for differences on various items like age, gender and further sociodemographic as well as crash related factors and clinical findings. RESULTS: Between 21.08.1997 and 30.04.1999 a total of 732 patients was examined and treated after whiplash in our trauma department. The options for inclusion were met by 453 patients. While 346 escaped from the study, 107 agreed to participate. Of these another 39 patients dropped out of the study. Selection effects were detected on two different levels, leading to distinct statistical procedures from those proposed in the study protocol. CONCLUSIONS: Uncontrolled selection effects could undermine the interpretability of the results of clinical trials. Awareness of selection effects is mandatory regarding the applicability of these results to subjects, other than those in the group of the final study participants.

Humans↗
PubMed2006

Detection of preclinical scrapie from serum by infrared spectroscopy and chemometrics.

In this study we describe a methodology for diagnosing preclinical scrapie infection in hamsters from serum by a combination of Fourier-transform infrared (FT-IR) spectroscopy and chemometrics. Syrian hamsters (Mesocricetus auratus) were orally inoculated with the 263K scrapie agent, or mock-infected, and sera were obtained at 70, 100 and 130 days post infection (dpi) and at the terminal stage of scrapie (160 +/- 10 dpi). The analysis of hamster sera by FT-IR spectroscopy and artificial neural networks (ANN) confirmed results from earlier studies which had indicated the existence of disease-related structural and compositional alterations in the sera of infected donors in the terminal stage of scrapie [Schmitt et al. (2002) Anal Chem 74:3865-3868]. Experimental data from sera of animals in the preclinical stages of scrapie revealed subtle but reproducible spectral variations that permitted the identification of a preclinical scrapie infection at 100 dpi and later, but not at 70 dpi. The IR spectral features that were discriminatory for the preclinical stages differed from those of the terminally ill individuals. In order to reliably identify scrapie-negative as well as preclinical (100 and 130 dpi) and terminal scrapie-positive animals, a hierarchical classification system of independent artificial neural networks (ANN) was established. A "toplevel" ANN was designed which discriminates between animals in the terminal stage of scrapie and preclinical scrapie-positive or control animals. Spectra identified by the "toplevel" ANN as preclinical or controls were then further analyzed by a second classifier, the "sublevel" ANN. Using independent external validation procedures, the toplevel classifier produced an overall classification accuracy of 98%, while the sublevel classifier yielded an accuracy of 93%, indicating that scrapie-specific serum markers were also present for preclinical disease stages. Possible spectral markers responsible for the discrimination capacity of the two different ANNs are discussed.

Animals↗
PubMed2007

Use of NIRS technology with a remote reflectance fibre-optic probe for predicting mineral composition (Ca, K, P, Fe, Mn, Na, Zn), protein and moisture in alfalfa.

In the present work we study the use of near-infrared spectroscopy (NIRS) technology together with a remote reflectance fibre-optic probe for the analysis of major (Ca, K, P) and minor (Fe, Mn, Na, Zn) elements, protein and moisture in alfalfa. The method allows immediate analysis of the alfalfa without prior sample treatment or destruction through direct application of the fibre-optic probe on ground samples in the case of the mineral composition and on-ground and compacted (baled) samples in the case of protein and humidity. The regression method employed was modified partial least-squares (MPLS). The calibration results obtained using samples of alfalfa allowed the determination of Ca, K, P, Fe, Mn, Na and Zn, with a standard error of prediction (SEP(C)) and a correlation coefficient (RSQ) expressed in mg/kg of alfalfa of 1.37x10(3) and 0.878 for Ca, 1.10x10(3) and 0.899 for K, 227 and 0.909 for P, 103 and 0.948 for Fe, 5.1 and 0.843 for Mn, 86.2 and 0.979 for Na, and of 1.9 and 0.853 for Zn, respectively. The SEP(C) and RSQ values (in %) for protein and moisture in ground samples were 0.548 and 0.871 and 0.150 and 0.981, respectively; while in the compacted samples they were 0.564 and 0.826 and 0.262 and 0.935, respectively. The prediction capacity of the model and the robustness of the method were checked in the external validation in alfalfa samples of unknown composition, and the results confirmed the suitability of the method.

Calibration↗
PubMedDate not supplied

Methodological and political issues in clinical pharmacology research by the year 2000.

Parallel groups in a large, multicenter, phase III "pivotal" randomized clinical trial (RCT) with clinically relevant end-points are seen by the medical community as the "gold standard" of clinical research. However, there are limitations, some methodological and others political. The main one is the external validity of the method because a treatment, as studied in RCTs, does not necessarily reflect how it is used in clinical practice. Also, the method, as it stands, is not really predictive of the success in a particular patient of a certain intervention studied in a trial. To overcome these methodological drawbacks, different options have been implemented. The most important ones are: (1) the performance of pragmatic RCTs intended to address effectiveness rather than efficacy; (2) meta-analysis; and (3) the use of observational studies, with or without a comparison group. Recent experience has shown that type-A adverse drug reactions (ADRs) related to a specific class of drugs have been successfully characterized throughout cohort- or population-based case-control studies, whereas the evidence linking a specific drug entity to a type-B ADR, apparently severe enough to withdraw the drug from the market, has come mainly from case reports or case series. Other limitations of the RCT are more of a political nature. These large "pivotal" trials are mostly sponsored by the pharmaceutical industry, and to guarantee the scientific and ethical integrity of data produced, they are performed following standard operating procedures (SOPs) and good clinical practice (GCP) guidelines. Sometimes industry is not interested in sponsoring trials; thus, RCTs performed are in practice highly biased because of their potential economical profits. Furthermore, applying SOPs and GCPs is expensive and difficult to implement, and it is hard to find funding in public institutions. As a result, there is an urgent need to create a network of independent, skilled groups interested in sponsoring and performing institutional RCTs following "user friendly" GCP when the profits are low, but scientific interest high.

Forecasting↗
PubMed2005

Patient's preference and randomization: new paradigm of evidence-based clinical research.

The limitations associated with the traditional randomized controlled design as applied to clinical surgical research must be recognized. The aim of randomization is to ensure initial comparability between groups of eligible patients for whom treatments are compared, thus eliminating their individual influence on outcome. Randomized controlled trials in the surgical literature are sparse; patient preferences might be a major obstacle to their performance. External validity of results of clinical trials depends on the representativity of patients who participate in trials: Compliance to participate through informed consent may act as a selection bias. In surgical randomized trials where it is not often possible for patients to remain blinded to the treatment to which they have been allocated, patient preferences can influence the effectiveness of treatments. In this setting, we need to look at alternatives and the potential advantages of adopting more flexible and clinically relevant approaches to the design of surgical trials. We have to accept the weight of the patient's individual decision in everyday practice. Hence, to negate the importance of these individual choices when evaluating surgical outcomes is unrealistic. An original design reported herein might become a new paradigm for surgical evaluation.

Ethics, Clinical↗
PubMed2002

German short musculoskeletal function assessment questionnaire (SMFA-D): comparison with the SF-36 and WOMAC in a prospective evaluation in patients with primary osteoarthritis undergoing total knee arthroplasty.

In a prospective clinical trial, the German short musculoskeletal function assessment (SMFA-D), the short form (SF)-36, and the Western Ontario and McMaster Universities osteoarthritis index (WOMAC) were evaluated in 63 patients with primary osteoarthritis undergoing total knee arthroplasty. All instruments were sensitive to change, demonstrating the effect of total knee arthroplasty at 1-year follow-up. The SMFA-D effect sizes in comparable scales were bigger than in the SF-36 and similar to those of the WOMAC. Significant correlations of the SMFA-D indices with the SF-36 and WOMAC scales preoperatively could be shown. After 1-year follow-up, all correlations between the SMFA-D indices and SF-36 scales were significant. In other comparison, only the correlation between the SMFA-D function index and the WOMAC function scales remained significant. The correlation of the SMFA-D function index with external validation criteria was higher than that using the other instruments. We recommend the SMFA-D for assessing change in functional status of patients with primary osteoarthritis of the knee following arthroplasty.

Arthroplasty, Replacement, Knee↗
PubMed2006

Intratympanic steroid therapy for inner ear diseases, a review of the literature.

To evaluate the value of clinical trials on intratympanic steroid therapy in Ménière's disease (MD), idiopathic sudden sensorineural hearing loss (ISSNHL) and rapidly progressive sensorineural hearing loss (RPSNHL). Medline and Pubmed databases from 1966 to present were searched for clinical studies on intra- or transtympanic (cortico)steroid therapy of MD, ISSNHL and RPSNHL. Results were cross-checked with additional databases to obtain a complete data set. Clinical trials were evaluated on the basis of comparability, internal and external validity. Articles were judged using the following questions: was a randomised double-blind controlled trial performed? Which criteria were used to confirm the diagnosis of MD, ISSNHL, RPSNHL? Which therapy was evaluated? How long was the follow-up? Which criteria were used to evaluate the results? Reliable evidence on the efficiency, optimum dosage and administration schedule of intratympanic steroid therapy in MD, ISSNHL and RPSNHL is lacking, therefore further investigation is required.

Anti-Inflammatory Agents↗
PubMed2007

The quantification inventory for somatoform syndromes (QUISS): a novel instrument for the assessment of severity.

BACKGROUND: To date, specific scales for the assessment of severity of somatoform disorders are still rare. Characteristic cognitive and behavioural domains, representing severity are not incorporated in the existing scales. Results with the novel quantification inventory for somatoform syndromes (QUISS) are presented in this paper. METHODS: The QUISS has been developed as a qualified severity scale for patients fulfilling diagnostic criteria according to DSM-IV or/and ICD-10. It was designed to be particularly suitable for application in clinical trials and for monitoring the efficacy of psychotherapy and pharmacotherapy. Not only number, severity and frequency of somatoform symptoms, but also common cognitive and behavioural domains of somatoform disorders have been included into this instrument. Both an 18-item patient- and observer-rated version are available taking about 20 min to complete. The questionnaire was applied to patients with somatoform disorder (N = 96), major depression (N = 24), and panic disorder (N = 16). RESULTS: The psychometric properties of the scale are satisfactory. The QUISS showed high objectivity (Cronbach's alpha = 0.90 for both versions; inter-scale correlations r = 0.64-0.88; p < 0.05), good test-retest- (r = 0.87; p < 0.05) and inter-rater-reliability (r = 0.89; p < 0.05). External validity (moderately high correlations of QUISS-T to SOMS 7T (r = 0.54), significant discrimination to major depression p < 0.05) was satisfactory. Factor structure revealed five relevant factors. CONCLUSIONS: The QUISS could be a useful instrument in somatoform disorders for the assessment of syndrome severity and treatment outcome in scientific and clinical settings.

Activities of Daily Living↗