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PubMed1999

A new measure of conversational experience: the speaking extent and comfort scale (SPEACS).

Few measures exist which directly assess aspects of conversational experience. We present and provide a psychometric assessment of the Speaking Extent and Comfort Scale (SPEACS), a new 20-item measure which assesses four aspects of past conversational experience: the extent and comfort of both general conversations and in conversations specifically about the self. All four SPEACS subscales exhibited good test-retest reliability. As predicted, the subscales related positively to social competence, disclosure, assertiveness, and perceived availability of someone to talk to, and negatively to social avoidance and social anxiety, providing support for their construct validity. Internal consistency data demonstrated that people tend to vary in how often and how comfortable they feel having conversations with different people. SPEACS offers a range of potential applications in areas with a focus on social networks, social experience and interaction, and the possibility of extension to other dimensions of conversational experience.

Adolescent↗

PubMed2003

EEG biofeedback vs. placebo treatment for attention-deficit/hyperactivity disorder: a pilot study.

METHOD: Seven children diagnosed with attention-deficit hyperactivity disorder (ADHD) were trained using a standard EEG biofeedback treatment protocol designed to alter SMR/theta ratios and reduce behavioral symptomatology diagnostic of ADHD. During alternate periods they were also trained using a placebo protocol that was identical to the treatment protocol, save that the association between EEG patterns and feedback to the participants was random. Single-case design elements were used to control for the effects of internal validity threats such as maturation, history, and treatment order. Two participants failed to complete all training sessions, and the effects of training on behavior were analyzed both including and excluding these non-completers. RESULTS: When all participants were included in analyses that controlled for overall trend, EEG biofeedback was found to be no more effective than the placebo control condition involving non-contingent feedback, and neither procedure resulted in improvements relative to baseline levels. When overall behavioral trends unrelated to training were not controlled for and non-completers were excluded from the analysis, it could be mistakenly concluded that EEG biofeedback is significantly more effective than placebo and that the effect sizes involved are moderate to large. These results indicate that many previous reports of the efficacy of EEG biofeedback for ADHD, particularly those presenting series of single cases, might well have been based on spurious findings.

Attention Deficit Disorder with Hyperactivity↗

PubMed1989

Analysis issues in school-based health promotion studies.

In school-based research, usually the nature of the intervention or other practical factors indicate that assignment of treatment be done by school or classroom rather than by individual student. In this situation, randomization of schools (or classrooms) and analysis by school means (or classroom means) provide a firm statistical basis for internal validity of the study. When the number of schools available is small, this approach is not practicable, and therefore the investigator must be both more creative in developing solutions and more cautious in interpreting the results. This article provides a number of suggestions which the authors hope will assist the field in dealing with such circumstances. The authors stress that the best approach to assessing treatment effect is a well-designed, properly analyzed randomized experiment. The suggestions in this article attempt to indicate how one might make the most that one can from more limited data.

Data Interpretation, Statistical↗

PubMed1992

The utilization of qualitative and quantitative data for health education program planning, implementation, and evaluation: a spiral approach.

The process of development of a Dutch smoking prevention project is described. An essential feature of the project is the combination and interaction of qualitative and quantitative research methods. It is advocated that each method has its own contribution and can be considered as a separate methodology contributing to social science in general and health education research in particular. Combining the two approaches in a spiral approach will result in a synergistic effect, because of the interaction of both approaches. The results of both methods suggest that qualitative methods enhanced the generation of ideas and theories. Qualitative methods were used to formulate ideas for improving quantitative data gathering, analyzing and comparing ideas with respect to program development, and for testing the internal validity of a quantitative design. The quantitative method enabled testing of results in different groups and detecting detailed differences. It also provided information that one of the assumptions of the program, the development of a teacher independent program, was not completely realized. The major advantage of using both methods is that this provides feedback between assumptions and data, thus enhancing comparison of results and critical reflection during the whole project.

Health Education↗

PubMed1994

CATCH: classroom process evaluation in a multicenter trial.

The purpose of this paper is to describe the process evaluation model for the classroom curricula of the Child and Adolescent Trial for Cardiovascular Health (CATCH) Project. The process evaluation plan specifically targets how much each curriculum was implemented, to what degree it was implemented as designed, and the barriers to implementation. Additionally, the rationale for each of the process evaluation measures and the instrument development process are presented. Data resulting from these measures will be essential in order to answer questions regarding the internal validity of the main outcomes of the project. Specific examples and sample results are provided from the CATCH third-grade classroom curriculum, which was implemented the first year of CATCH. A discussion also is presented of how the findings from a sample of these measures were used to gain additional insight on the salient features of the curriculum, and how those features may be related to student outcomes.

Adolescent↗

PubMed2000

Psychometric properties of the Swedish version of the Well-Being Questionnaire in a sample of patients with diabetes type 1.

OBJECTIVES: The aim of the present investigation was to further test the psychometric properties of a Swedish version of the Well-Being Questionnaire (WBQ) in order to determine whether it could be suitable for measuring health-related quality of life among type 1 diabetic patients. METHODS: In total, 94 patients who fulfilled the inclusion criteria were selected for the study and of these 85% participated. Reliability was tested with Cronbach's alpha coefficient and the internal validity by means of principal component analysis and multitrait analysis. To test the external validity, comparisons were made with two other questionnaires, the Short form-36 and a Swedish Mood Adjective Check List. RESULTS: The results show that, above all, the Swedish version of the WBQ measures psychological well-being, and thus must also be complemented with scales that measure other consequences of the illness and/or treatment, i.e. physical symptoms. The questionnaire has low discriminatory validity between subscales, which casts doubt on the appropriateness of using the four subscales as separate measures. The two scales measuring anxiety and depression are not sensitive enough for use among type 1 diabetics without complications and high or normal levels of psychological well-being. CONCLUSIONS: The Well-Being Questionnaire alone does not give any more information about subjective health status among type 1 diabetic patients than, for example, the generic SF-36.

Adult↗

PubMed2003

An evaluation of the quantity and quality of empirical research in three pastoral care and counseling journals, 1990-1999: has anything changed?

This article summarizes a review of all articles published in Pastoral Psychology, The Journal of Rleigion and Health, and The Journal of Pastoral Care between 1900 and 1999, identifying a total of 737 scholarly articles, of which 165 (22.4%) were research studies. The proportion of research studies, especially quantitative studies, increased significantly between the first and second half of the study period (p < .05). There was a significant positive correlation between compliance with three out of four criteria of internal validity. Three of five criteria of external validity were also positively related to one another. Compared to previous research using identical criteria to assess quantitative studies in the same journals in 1980-1989, the 1990-1999 sample showed improved compliance with respect to specifying the sampling method (p < .001), reporting the response rate (p < .05), and discussing the limitations of research studies (p < .001). However, the overall findings suggest that many researchers in the field do not have a sophisticated knowledge of statistical sampling, statistical analysis, or research design. Several recommendations for increasing the quality of quantitative research are offered.

Bibliometrics↗

PubMed2004

Managing data for a multicountry longitudinal study: experience from the WHO Multicentre Growth Reference Study.

The World Health Organization (WHO) Multicentre Growth Reference (MGRS) data management protocol was designed to create and manage a large data bank of information collected from multiple sites over a period of several years. Data collection and processing instruments were prepared centrally and used in a standardized fashion across sites. The data management system contained internal validation features for timely detection of data errors, and its standard operating procedures stipulated a method of master file updating and correction that maintained a clear trail for data auditing purposes. Each site was responsible for collecting, entering, verifying, and validating data, and for creating site-level master files. Data from the sites were sent to the MGRS Coordinating Centre every month for master file consolidation and more extensive quality control checking. All errors identified at the Coordinating Centre were communicated to the site for correction at source. The protocol imposed transparency on the sites' data management activities but also ensured access to technical help with operation and maintenance of the system. Through the rigorous implementation of what has been a highly demanding protocol, the MGRS has accumulated a large body of very high-quality data.

Child Development↗

PubMed2001

Assessment of passive respiratory mechanics in infants: double versus single occlusion?

The single breath or occlusion technique (SOT) is widely used to assess passive respiratory mechanics in infants, but depends on various underlying assumptions. Recently, it has been proposed that such measurements could be internally validated by performing two brief airway occlusions during the same expiration. The aim of this study was to evaluate the use of the double occlusion technique (DOT) using a new commercially available program (Jaeger MasterScreen BabyBody Erich Jaeger GmbH, Würzburg, Germany). Paired measurements of respiratory system compliance (Crs) and resistance (Rrs) using both SOT and DOT were obtained in 18 healthy sedated infants (age range 4-41 weeks, weight 2.7-9.9 kg). There was close agreement between both methods of assessing Crs in all infants, the mean within-subject difference (95% confidence interval (CI)) for DOT-SOT being -0.06 (-0.55- +0.42) mL x kPa(-1) x kg(-1). By contrast, estimates of Rrs,DO were on average 20% lower than those for Rrs,SO, (mean within-subject difference (95% CI) being -0.67 (-1.04- -0.31) kPa x L(-1) x s; p<0.01). The relatively lower values obtained for Rrs,DO may reflect the higher mean lung volume at which it was calculated. Further work is required to investigate the clinical and epidemiological relevance of this new approach, and whether there are any advantages of using both techniques when assessing passive mechanics in infants.

Humans↗

PubMed2005

The association of prolonged breastfeeding and allergic disease in poor urban children.

The fact that breastfeeding may protect against allergic disease remains controversial, with hardly any reports from developing countries. This study investigated the association between allergic disease in children and prolonged breastfeeding. Data were collected from a 15% random sample of households from two poor suburbs of Cape Town, South Africa. Parents completed a validated International Study on Asthma and Allergies in Childhood questionnaire on allergic diseases for children aged 6-14 yrs. Other questions included breastfeeding duration, maternal smoking and parental allergy. Results were adjusted for possible confounders and for possible clustering within the household. Out of the 861 children included in the study, allergic disease in general, and hay fever in particular, were significantly less frequent in those with prolonged (> or =6 months) breastfeeding. There was a significant linear inverse association between breastfeeding duration and allergic disease in children without allergic parents, but not in children with an allergic predisposition. In conclusion, these results from a developing country suggest a protective effect of prolonged breastfeeding on the development of allergic disease, particularly hay fever, in children born to nonallergic parents. This protective effect was not found in children with an allergic predisposition.

Adolescent↗

PubMed2006

Setting directions for capacity building in primary health care: a survey of a research network.

BACKGROUND: The South Australian Research Network 'SARNet' aims to build research capacity in primary health care, as part of a national government-funded strategy to integrate research into clinical practice. Internationally, research networks have been a fundamental part of research culture change, and a variety of network models exist. The 'SARNet' model uses a whole system, multidisciplinary approach to capacity building and supports individuals and groups. We undertook a descriptive baseline survey in order to understand the background and needs of SARNet members and to tailor network activities towards those needs. METHODS: A questionnaire survey, assessing members' professional background, research experience, and interest in research development and training, was sent to all members who joined the network in its first year. The visual 'research spider' tool was used to ascertain members' experience in ten core research skills, as well as their interest in developing these skills. Individuals were asked to classify themselves into one of four categories of researchers, based on previous research experience. These self-assessment categories ranged from non-participant to academic. RESULTS: Network membership was diverse. Of the 89 survey participants, 55% were general practitioners or allied health professionals. Overall, most survey respondents indicated little to moderate experience in 7 out of the 10 skills depicted in the 'research spider'. In comparison, respondents were generally highly interested in developing their research skills in all areas. Respondents' research skills correlated significantly with their self-assessed category of research participation (Spearman rank correlation, r = 0.82, p < 0.0005). Correlations between research category and publication record (Gamma association, gamma = 0.53, p < 0.0005) or funding record (Gamma association, gamma = 0.62, p < 0.0005) supported the internal validity of the survey instrument. CONCLUSION: Literature describing evaluation of the impact of networks is scarce. Our survey questionnaire could provide a useful instrument for evaluation of both networks and capacity building initiatives. The survey including the 'research spider' tool provided valuable information about members' needs and interest in strategies to develop their research skills. Initial needs analyses as well as on-going evaluation of network activities are important to include into the business plans of research networks, in order to ensure the network's effectiveness and support of its membership.

Adult↗

PubMed2003

Postsurgical pain outcome of vertical and transverse abdominal incision: design of a randomized controlled equivalence trial [ISRCTN60734227].

BACKGROUND: There are two ways to open the abdominal cavity in elective general surgery: vertically or transversely. Various clinical studies and a meta-analysis have postulated that the transverse approach is superior to other approaches as regards complications. However, in a recent survey it was shown that 90 % of all abdominal incisions in visceral surgery are still vertical incisions. This discrepancy between existing recommendations of clinical trials and clinical practice could be explained by the lack of acceptance of these results due to a number of deficits in the study design and analysis, subsequent low internal validity, and therefore limited external generalisability. The objective of this study is to address the issue from the patient's perspective. METHODS: This is an intraoperatively randomized controlled observer and patient-blinded two-group parallel equivalence trial. The study setting is the Department of General-, Visceral-, Trauma Surgery and Outpatient Clinic of the University of Heidelberg, Medical School. A total of 172 patients of both genders, aged over 18 years who are scheduled for an elective abdominal operation and are eligible for either a transverse or vertical incision. To show equivalence of the two approaches or the superiority of one of them from the perspective of the patient, a primary endpoint is defined: the pain experienced by the patient (VAS 0-100) on day two after surgery and the amount of analgesic required (piritramide [mg/h]). A confidence interval approach will be used for analysis. A global alpha-Level of 0.05 and a power of 0.8 is guaranteed, resulting in a size of 86 patients for each group. Secondary endpoints are: time interval to open and close the abdomen, early-onset complications (frequency of burst abdomen, postoperative pulmonary complications, and wound infection) and late complications (frequency of incisional hernias). Different outcome variables will be ranked by patients and surgeons to assess the relevance of possible endpoints from the patients' and surgeons' perspective. CONCLUSION: This is a randomized controlled observer and patient-blinded two-group parallel trial to answer the question if the transverse abdominal incision is equivalent to the vertical one due to the described endpoints.

Abdominal Pain↗

PubMed2004

Measuring mental health of the Dutch population: a comparison of the GHQ-12 and the MHI-5.

BACKGROUND: The objective is to compare the performance of the MHI-5 and GHQ-12, both measures of general mental health. Therefore, we studied the relationship of the GHQ-12 and MHI-5 with sociodemographic characteristics, self-reported visits to general practice and mental health care, and with diagnoses made by the general practitioner. METHODS: Data were used from the Second Dutch National Survey of General Practice, which was carried out in 104 practices. This study combines data from a representative sample of the Dutch population with data from general practice. RESULTS: The agreement between the GHQ-12 and MHI-5 is only moderate. Both instruments are however similarly associated with demographic characteristics (except age), self-reported health care use, and psychological and social diagnoses in general practice. CONCLUSIONS: The performance of the MHI-5 and GHQ-12 in terms of predicting mental health problems and related help seeking behaviour is similar. An advantage of the MHI-5 is that it has been widely used, not only in surveys of mental health, but also in surveys of general health and quality of life, and it is shorter. A disadvantage of the MHI-5 is that there is no cut-off point. We recommend a study to establish a valid, internationally comparable cut-off point.

Adolescent↗

PubMed2006

Pain in cancer. An outcome research project to evaluate the epidemiology, the quality and the effects of pain treatment in cancer patients.

BACKGROUND: Management of pain related to advanced or metastatic cancer, although the availability of several pharmacological and non-pharmacological interventions and the existence of well-known guidelines and protocols, is often difficult and inadequate. Evidence of the relative effectiveness of current options for treating cancer pain from comparative randomized studies is scanty. METHODS: In the context of a wider project, a multicenter, open label, prospective Outcome Research study will be launched in Italy in 2006 to investigate the epidemiology of cancer pain and of its treatments, the quality of analgesic-drug therapy and the effectiveness of alternative analgesic strategies in a large, prospective, unselected cohort of cancer patients using the state-of-the art of patient-reported-outcomes. About 100 Italian centers will recruit 2500 patients with advanced/progressive/metastatic cancer with pain (related to the cancer disease) requiring analgesic treatments. Each center is expected to recruit 25 consecutive and eligible patients during the study inception period. Approximately two months will be allowed for subject recruitment and enrollment. Subject evaluation and follow-up will be for 3 months. The effect on outcomes of various therapeutic analgesic options administered by physicians, given the observational approach where patients are not assigned at random to different treatments, will be compared using the propensity score approach, allowing the adjustment for treatment selection bias. Later, after the launch of the observational study and on the basis of results, in specific subsamples of patients and in select centers of the network, a Randomized Controlled Trial will be carried out to formally compare the efficacy of alternative analgesic strategies, with particular emphasis on oral morphine (as comparator) and buprenorphine patch (as experimental arm). Results from the outcome (cohort) and experimental (Randomized Controlled Trial) studies will ensure both the external and internal validity.

Adult↗

PubMed2006

Generalizability in two clinical trials of Lyme disease.

OBJECTIVE: To examine the generalizability of two National Institutes of Health (NIH)-funded double-blind randomized placebo-controlled clinical trials in patients with chronic Lyme disease and to determine whether selection factors resulted in the unfavorable outcomes. DESIGN: Epidemiologic review of the generalizability of two trials conducted by Klempner et al. This paper considers whether the study group was representative of the general chronic Lyme disease population. RESULTS: In their article in The New England Journal of Medicine, Klempner et al. failed to discuss the limitations of their clinical trials. This epidemiologic review argues that their results are not generalizable to the overall Lyme disease population. The treatment failure reported by the authors may be the result of enrolling patients who remained ill after an average of 4.7 years and an average of 3 previous courses of treatment. The poor outcome cited in these trials may be explained by having selected patients who had undergone delayed treatment or multiple treatments unsuccessfully. These selection factors were not addressed by the studies' authors, nor have they been discussed by reviewers. The trials have been over-interpreted by the NIH and widely publicized in a press release. The results have been extrapolated to other groups of Lyme disease patients by commentators, by a case discussant in an influential medical journal, and by health insurance companies to deny antibiotic treatment. CONCLUSION: The Klempner et al. trials are assumed to be internally valid based on a Randomized Control Trial (RCT) design. However, this review argues that the trials have limited generalizability beyond the select group of patients with characteristics like those in the trial. Applying the findings to target populations with characteristics that differ from those included in these trials is inappropriate and may limit options for chronic Lyme disease patients who might benefit from antibiotic treatment.

Journal Article↗

PubMed2003

Simplified Acute Physiology Score III: a project for a new multidimensional tool for evaluating intensive care unit performance.

The Simplified Acute Physiology Score III Outcomes Research Group is developing an international multidimensional instrument for the global evaluation of intensive care unit performance. Among its specific objectives are the update of a severity of illness index (Simplified Acute Physiology Score) with a mortality prediction equation, with the hindsight of recent years, and the creation or application of novel instruments in the areas of infections and cost-effectiveness. Some important measurements such as the quality of life and the satisfaction of patients and professionals are not included. A further aim is the achievement of international validation.

APACHE↗

PubMed2026

Proteomic and machine learning analysis predicts treatment response signatures in Myasthenia Gravis.

BACKGROUND: Myasthenia gravis (MG) is a prototypical antibody-mediated autoimmune disease with variable treatment responses with a need for biomarkers to guide therapeutic decision making. Proteomic profiling, coupled with machine learning, offers a hypothesis-free approach to identify multi-protein signatures associated with treatment response. METHODS: We analyzed sera collected at entry (baseline) from participants in a phase 3 trial randomized trial comparing thymectomy plus prednisone versus prednisone alone, along with matched controls using liquid chromatography-mass spectrometry. We derived disease-specific proteomic signatures and evaluated associations between baseline proteins and 6-month clinical outcomes using multiple machine-learning approaches with internal validation. RESULTS: Baseline serum proteomes distinguished MG from controls, with pathway enrichment implicating complement activation, immunoglobulin production, and T-cell receptor signaling. Distinct protein panels predicted 6-month clinical improvement within each treatment arm. In the thymectomy-plus-prednisone group, models captured non-linear relationships of predictive proteins in contrast with the predominant additive patterns observed in the prednisone-alone group. Predictive proteins were enriched for T-cell signaling and leukocyte trafficking functions, providing insight into treatment-specific biology. CONCLUSIONS: Baseline serum proteomics captures core disease characteristics of MG and predicts short-term clinical response in a treatment-specific manner. While our results require validation in independent cohorts, these findings could enable biomarker-guided selection of thymectomy, refine risk stratification, and furnish mechanistic readouts for future MG trials and clinical care. We aim to conduct future studies using -omic approaches to validate these baseline predictive biomarkers and pathways of treatment response in patients with MG.

Adult↗

PubMed2002

Systematic review of conservative interventions for subacute low back pain.

OBJECTIVE: To evaluate the effect of conservative interventions on clinically relevant outcome measures for patients with subacute low back pain. This is particularly important because effective treatment for subacute low back pain will prevent the transition to chronic low back pain, a condition that is largely responsible for the high health care costs of low back pain. DESIGN: Systematic review of randomized controlled trials. MAIN OUTCOME MEASURES: Methodological quality of each trial was assessed. Effect sizes and 95% confidence intervals were calculated for pain and disability and risk ratios for return to work. RESULTS: Thirteen trials were located, evaluating the following interventions: manipulation, back school, exercise, advice, transcutaneous electrical nerve stimulation (TENS), hydrotherapy, massage, corset, cognitive behavioural treatment and co-ordination of primary health care. Most studies were of low quality and did not show a statistically significant effect of intervention. For the strict duration of low back pain (six weeks to three months), no evidence of high internal validity was found but when other methodological criteria were considered, evidence was found for the efficacy of advice. Furthermore, there is evidence that when a broader view is taken of the duration of subacute low back pain (seven days to six months), other treatments (e.g. manipulation, exercise, TENS) may be effective. CONCLUSIONS: Our review identified a major gap in the evidence for interventions that are currently recommended in clinical practice guidelines for the treatment of subacute low back pain. Lack of a uniform definition of subacute low back pain further limited current evidence.

Cognitive Behavioral Therapy↗