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PubMed2004

Comparison of ADHD symptom subtypes as source-specific syndromes.

BACKGROUND: This study examines differences between the three subtypes of attention-deficit/hyperactivity disorder (ADHD), inattentive (I), hyperactive-impulsive (H), and combined (C), in a heterogeneous sample of 248 boys (ages 6 to 10 years) with emotional and behavioral problems who were recruited for participation in a diagnostic study. METHOD: The boys and their mothers participated in an extensive evaluation that involved multiple assessments of cognitive, behavioral, academic, and family functioning. ADHD subtypes were defined on the basis of teacher alone, mother alone, and mother/teacher ratings of DSM-IV symptoms. RESULTS: Results indicated ADHD symptom groups showed a differential pattern of impairment socially (H,C>I) and cognitively (I,C>H). The C and H groups were the most and least impaired overall, respectively, and all subtypes were differentiated from the nonADHD clinical control or NONE (N) group in a manner consistent with the primary findings. External validation of group differences was limited, and there were marked inconsistencies in the pattern of findings depending on how groups were defined. For the most part, although the mother/teacher grouping strategy (compared with either alone) captured a greater diversity of differences between subtypes, it also obscured some. CONCLUSIONS: Observed findings are consistent with the notion that mothers and teachers interpret symptom statements in terms of behaviors that are most relevant for their daily concerns.

Attention Deficit Disorder with Hyperactivity↗
PubMedDate not supplied

Factors influencing treatment-seeking behavior in problem headache sufferers.

Subject samples used in research on recurrent headache disorders typically are composed of individuals who are seeking or receiving treatment. To the extent such subjects are unrepresentative of the larger population of recurrent headache sufferers, the external validity of findings may be jeopardized. We examined young recurrent (tension-type or migraine) headache sufferers and compared individuals who had sought treatment (N = 81) and individuals who had not sought treatment (N = 109) for their headache problem. Subjects who did not experience headaches (N = 129) served as a comparison group. Recurrent headache sufferers who had sought treatment reported more frequent headaches and experienced problem headaches for a longer period of time than recurrent headache sufferers who had not sought treatment for their headaches. However, the two treatment-seeking groups did not differ on measures of psychological symptoms, coping strategies, or beliefs about their headache disorder. Irrespective of whether they had sought treatment or not sought treatment for their headache problems, recurrent headache sufferers reported higher levels of depression and physical symptoms than comparison subjects. These results provide no support for the hypothesis that psychological symptoms or neuroticism are associated with treatment-seeking behavior in recurrent headache sufferers.

Adaptation, Psychological↗
PubMed2005

The accuracy of outcome prediction models for childhood-onset epilepsy.

PURPOSE: Two large prospective cohort studies of childhood epilepsy (Nova Scotia and the Netherlands) each developed a statistical model to predict long-term outcome. We sought to evaluate the accuracy of a prognostic model based on the two studies combined. METHODS: Analyses with classification tree models and stepwise logistic regression produced predictive models for the combined dataset and the two separate cohorts. The resulting models were then externally validated on the opposite cohort. Remission was defined as no longer receiving daily medication for any length of time at the end of follow-up. RESULTS: The combined cohorts yielded 1,055 evaluable patients. At the end of follow-up (>or=5 years in >96%), 622 (59%) were in remission. By using the combined data, the classification tree model and the logistic regression model predicted the outcome correctly in approximately 70%. The classification tree model split the data on epilepsy type and age at first seizure. Predictors in the logistic regression model were: seizure number before treatment, age at first seizure, absence seizures, epilepsy types of symptomatic generalized and symptomatic partial, preexisting neurologic signs, intelligence, and the combination of febrile seizures and cryptogenic partial epilepsy. When the prediction models from each cohort were cross-validated on the opposite cohort, the outcome was predicted slightly less accurately than did the model from the combined data. CONCLUSIONS: Based on currently available clinical and EEG variables, predicting the outcome of childhood epilepsy may be difficult and appears to be incorrect in about one of every three patients.

Age of Onset↗
PubMed1990

Designing and executing randomized clinical trials involving elderly persons.

Although randomized clinical trials are the most scientifically rigorous design for evaluating a clinical intervention, the methodology involved is intricate, particularly when elderly subjects are involved. Special attention must be paid to framing precise primary and secondary study hypotheses, adjusting for the potential confounding effects of comorbidity and disability, and analyzing multiple outcomes. When the sample or study cohort is chosen, there will be an inevitable trade-off between internal and external validity. Because elderly study cohorts are more prognostically heterogeneous, consideration should be given to enrolling an "at-risk" cohort and possibly to stratified randomization.

Aged↗
PubMed2006

Polymorphisms of prostaglandin-endoperoxide synthase 2 gene, and prostaglandin-E receptor 2 gene, C-reactive protein concentrations and risk of atherothrombosis: a nested case-control approach.

OBJECTIVE: Recent data have shown an association between polymorphisms of prostaglandin-endoperoxide synthase-2 gene (PTGS2; alias COX-2), and prostaglandin-E receptor-2 gene (PTGER2) and risk of atherothrombotic disorders. METHODS: We evaluated two PTGS2 (rs20417, rs689470), and three PTGER2 (rs708494/uS5, rs708495/uS7, and chr14: 50 764 013/uS10) gene polymorphisms among 600 Caucasian male participants of the Physicians' Health Study with incident myocardial infarction (MI) or ischemic stroke and 600 age- and smoking-matched controls who remained free of all reported cardiovascular disease. RESULTS: Genotype distributions were in Hardy-Weinberg equilibrium in the control groups. Genotype and allele distribution were similar between cases and controls. The polymorphisms tested were in linkage disequilibrium. Results from the adjusted haplotype-based conditional logistic regression analysis showed a modest association of the PTGER2 2-1-1 haplotype with reduced risk of MI (odds ratio = 0.50, 95% CI; CI = 0.26-0.97, P = 0.04), and the 2-2-1 haplotype with reduced risk of ischemic stroke (odds ratio = 0.68, 95% CI = 0.47-0.99, P = 0.048). In contrast to prior data, we found no evidence for an association of the PTGS2 polymorphisms/haplotypes tested with risk of incident MI nor with ischemic stroke. However, we found suggestive evidence for an association of specific PTGER2 haplotypes with reduced risk of these outcomes. CONCLUSION: Although these prospective data implicate the potential involvement of prostaglandin-E receptor-2 gene variation in atherothrombosis, external validation of our findings is needed.

Adult↗
PubMed2006

Cross-cultural reliability of the Health Perception Index and the Health Control and Competence Index.

PURPOSE: To test the reliability of two Spanish instruments to measure (a) health perceptions, and (b) health control and competence. DESIGN: Triangulated methodology used with two different Latino populations. METHODS: Preliminary qualitative data were collected in Mexico. Based on themes from Mexico, data were collected from 44 men (Dominican Republic, n=24 ; Peru, n=20) with two instruments, the Health Competence and Control Index and the Health Perception Index. Alpha reliability estimates were obtained. FINDINGS: Results of the study confirmed reliability of the instruments in one of the Latino populations, consistent with understanding of the constructs found in the Mexican study. Reliability was low in the second Latino population. CONCLUSIONS: Although results from this study are useful, further translation and research procedures are needed to address the many differences among ethnically similar groups and to further strengthen internal and external validity of instruments designed to assess Latino men's perceptions of health and their control over health.

Adolescent↗
PubMed2002

Radiology services in emergency medicine residency programs: a national survey.

OBJECTIVES: To determine who reads plain film radiographs, how quickly radiologists' interpretations are available, how many initial readings require correction, and how satisfied emergency physicians (EPs) are with radiology in emergency departments (EDs) with emergency medicine (EM) residency programs. METHODS: A questionnaire was sent to the chairs of all U.S. EM residencies, asking about EM radiology services. RESULTS: Of 120 sites surveyed, 97 (81%) responded. Respondents reported that, on weekday days, EM attendings or residents performed the radiograph interpretation used for clinical decision making at 66% of sites; on nights and weekends, EPs performed the clinically relevant readings at 79% of sites. Twenty-one percent of sites reported that no radiologist reviewed images before patients left the ED on nights and weekends. Only 39% of sites reported that all images were read within four hours on weekday days, and only 19% of sites reported readings within this time frame on nights and weekends. Median misinterpretation rates were reported as 1% on weekday days and 1.5% at other times. Overall, EPs were satisfied with their interactions with radiology at 63% of EDs. CONCLUSIONS: This study summarizes the perceptions of EPs regarding radiology services; the findings must be interpreted with caution, given the lack of external validation. Nevertheless, EPs report that many EM residency programs depend on EPs' interpretations of radiographs. Emergency physicians report that attending radiologists rarely read images on nights and weekends and that images are misread more frequently at these times. Although EPs were satisfied with many aspects of radiology, EPs expressed the most dissatisfaction with turnaround times and misreads.

Diagnostic Errors↗
PubMed2003

The caring physician: a journey in self-exploration and self-care.

Caring for patients involves empathic listening and awareness of the needs and feelings of the patient as well as our own; the acceptance of the fallibilities of medicine and ourselves. Too often we lead unbalanced lives in terms of work, relationships, play and personal time. We frequently strive for perfection, deny our needs and feelings, assume total responsibility for the patient, and are altruistic to the point of self-denial. Caring for patients without adequately caring for ourselves is frequently associated with subconscious needs for external validation. The hidden agenda may be harmful to the patient and the physician. Change requires self-awareness and recognition of the overt and covert benefits and risk of our current work patterns. Often there is a need to reexamine our life priorities, set limits at work, admit vulnerability, share our emotional lives, and appreciate the small things in our daily life that give us meaning and purpose.

Attitude of Health Personnel↗
PubMed1986

Chinese diagnostic interview schedule. I. Agreement with psychiatrist's diagnosis.

NIMH-DIS was translated into Chinese and modified to the Chinese version of DIS (DIS-CM). One hundred clinical patients and 187 community subjects were studied for diagnostic agreement between the DIS-CM and the psychiatrist's clinical diagnosis. In the community sample, DIS-CM overdiagnosed the cases of manic episode, phobic disorder, obsessive-compulsive disorder and alcoholic problem, while it underdiagnosed the cases of tobacco dependence in the community sample and manic episode in the clinical cases. Standard diagnostic criteria, method of symptom detection, and social desirability, were identified as the major factors contributing to the diagnostic disparity. Variables related to life situations, language habit and medical histories were also analysed to test the external validity of the DIS-CM in case identification. The results affirm that the DIS-CM is reliable as a psychiatric epidemiological tool.

Alcoholism↗
PubMed1992

A cluster-analytically derived subtyping of chronic affective disorders.

This article aims to propose a mathematically legitimate and externally validated subclassification of chronic affective disorders. Three subtypes emerged from the cluster analysis of the symptom data of 40 patients with chronic affective disorder that had been present without remission for more than 2 years; the subtypes were then validated by psychosocial variables. The first cluster, a predominantly male group with young onset, is characterized by past history of psychotic features and is named psychotic subtype. The second cluster, a predominantly female group with late onset, is tentatively called late-onset female subtype. The third cluster has the youngest onset and the longest duration, and is characterized by early object loss and high neuroticism score: depressive personality subtype.

Adult↗
PubMed1996

Do endogenous features in depression predict the risk of psychiatric illness in relatives?

We sought to evaluate the hypothesis that endogenous symptoms define a form of depression that is relatively distinct from a familial perspective. Cox models examined the relationship between endogenous symptoms in 88 epidemiologically ascertained cases of treated major depression and the risk for a range of psychiatric disorders in relatives. Endogenicity did not predict risk of major depression, bipolar disorder, anxiety disorders, schizophrenia, or schizophrenia spectrum illnesses in relatives. Risk in relatives of illness as an external validator of endogenous depression is not supported by our family study data.

Depressive Disorder↗
PubMed1981

Longitudinal evaluation of a preventive program provided by general dental practitioners to young adult Danes.

In 1976, a preventive program was established for young adults under the general feasibility of public economic support for preventive dentistry was studied longitudinally during the years 1976-80. Out of approximately 140,000 evaluation cards sent out, 42,000 were returned from general dental practitioners concerning 20,000 individuals, 12,000 of whom were reported twice or more. Information was collected on use of preventive service and health status based on Visible Plaque Index (VPI) and Gingival Bleeding Index (GBI). About one-fifth of the study population received the preventive service, consisting of chairside dental education and oral hygiene instruction. Associations between provision of prevention and VPI/GBI scores were found. From first to last dental visit in the evaluation period improvement in VPI and GBI scores was registered, proportionally more in the group that received service. Internal and external validity of the results and policy implications of the study are discussed.

Adult↗
PubMed2004

Thermal comfort in practice.

UNLABELLED: Since the early twentieth century when air-conditioning began penetrating the market in a serious way, there has been a need for human factors research upon which HVAC engineering practice could be based. Now we have nearly a century of thermal comfort research from climate chambers and much has been learnt in that time. By stripping the research problem back to essential cause-and-effect variables, climate chamber methods have delivered results that are amenable to rigorous data analyses leading to unequivocal conclusions. However, in the minds of HVAC practitioners there are persistent doubts about the experiential realism of the chamber methodology, and the external validity of their findings, in particular, their relevance to building occupants going about their normal daily routines in fully-engineered indoor climatic environments. In response to this methodological concern in the 1990s, ASHRAE commissioned a series of thermal comfort studies aimed at field validating the findings of climate chamber research and the HVAC standards based upon them in a variety of climatic contexts around the world. This paper discusses the methodological benefits and constraints of conventional climate chamber research in comparison to the field-based alternative. In particular, issues such as sample size and demographics, research design, instrumentation and indoor climatic measurement procedures, questionnaires, clothing insulation and metabolic rate assessment techniques are analyzed. The discussion of methodology is then extended to the discipline of environmental psychology, which should have made a much more significant contribution to the topic of thermal comfort, and yet has remained relatively silent. The paper finishes by considering why engineers, most notably P.O. Fanger, have come to dominate a research topic that falls so clearly within the scope of psychology. HVAC engineering is the profession most directly occupied in the practice of thermal comfort, and therefore an engineer such as Fanger has been ideally qualified to design and conduct research, and even more important, presents its results in a way most directly useful to thermal comfort practitioners. PRACTICAL IMPLICATIONS: The paper gives practical advice on evaluating and designing for thermal comfort.

Air Conditioning↗
PubMed2005

Variance components of gingival thickness.

OBJECTIVES: Distinct periodontal phenotypes have been identified by cluster analysis, which is an explorative method with very low external validity. The aim of the present study was to investigate variance components of facial gingival thickness in young adults with mild gingivitis. MATERIAL AND METHODS: Thirty-three non-smoking females, 18-23 years of age, with mild or moderate plaque-induced gingivitis participated. Gingival thickness was measured at every tooth present by use of ultrasound technology to the next 0.1 mm with a lowest measurement of 0.5 mm. Periodontal probing depth and clinical attachment level were measured with a pressure-controlled probe. Gingival bleeding index was assessed after probing on a 0-2 scale, where 1 was slight, and 2 was profuse bleeding on probing. The Silness-Loe plaque index was recorded. Multilevel variance components and random intercept models were built. RESULTS: A 2-level (subject, tooth) variance component model of gingival thickness without any explanatory variable revealed an intercept (mean) of 0.93 +/- 0.02 mm. Subject variation of gingival thickness amounted to 4.2% of the total variance. Addition of tooth- and subject-related covariates to the model revealed, after adjusting for tooth type, an association with periodontal probing depth (estimated coefficient 0.067 +/- 0.025), and considerable association with average bleeding index (-0.395 +/- 0.149) and plaque index (0.125 +/- 0.048). Variation at the tooth level was drastically reduced; subject variation amounted to 5.2%. CONCLUSION: Gingival thickness is mainly associated with tooth-related variables. Bleeding tendency is higher if gingiva is thin. Subject variability related to periodontal phenotype may add to the total variance, however, to a very low extent.

Adolescent↗
PubMed2007

Agreement between Cochrane Neonatal Group reviews and clinical guidelines for newborns at a Copenhagen University Hospital - a cross-sectional study.

AIM: To assess the agreement between Cochrane Neonatal Group reviews and clinical guidelines of a University Neonatology Department, to evaluate the reasons for potential disagreements and to ascertain whether Cochrane reviews were considered for the guidelines development. METHODS: The recommendations in the reviews and guidelines were compared and classified as being in 'agreement', 'partial agreement' or 'disagreement'. The guideline authors were interviewed for reasons about disagreement and whether Cochrane reviews were considered during the guideline development. RESULTS: Agreement between reviews and guidelines was found for 133 interventions (77%), partial agreement for 31 interventions (18%) and disagreement for nine interventions (5%). Six interventions were recommended in the guidelines, but not in the reviews. Three interventions were recommended in the reviews, but not in the guidelines. Use of consensus statements, evidence on surrogate markers, observational studies, basic immunology and pathophysiological knowledge, expert opinion, economical constraints, reservations about the external validity and unawareness of reviews were reasons for disagreement. Cochrane reviews were rarely (22%) used during the guideline development. CONCLUSION: We found agreement between more than three quarters of Cochrane reviews and neonatal guidelines. However, few important disagreements occurred. Reviews were only used for guideline development in about a fifth of cases.

Consensus↗
PubMed1997

The normative need for tooth extractions in older adults in Ontario, Canada.

OBJECTIVE: To determine the reasons for clinically defined need for tooth extractions were examined. DESIGN: Descriptive survey; interview and clinical data. SETTING: The City of North York, Canada. SUBJECTS: 1,531 dentate adults aged 65 and over, 69% being nursing home residents. MEASUREMENTS: Age, sex, type of residence and dental attendance pattern. OUTCOME MEASURE: Normative need for tooth extraction. RESULTS: One or more extractions were required by 38% of nursing home residents and 21% of independently-living subjects. The mean number of teeth indicated for extraction were 1.4 and 0.6, respectively. Among nursing home residents, caries was more often the reason for extraction for almost all tooth types, but for independently-living subjects periodontal reasons were more common. Overall, a significantly higher proportion of nursing home residents needed extractions due to both caries and periodontal reasons (25% and 16%) compared to subjects who lived independently (10% and 11%). For nursing home residents in all age groups, more subjects required caries-related extractions, but for independently-living subjects about equal proportions required extractions due to caries and periodontal diseases. Although the percentage of subjects requiring extraction due to caries varied significantly by age and residence type, the percentage needing extractions due to periodontal diseases showed slight variation and remained under 20%. CONCLUSION: This study indicates that among high risk groups of older adults caries continues to be the major reason for tooth extraction. However, problems with sampling limit the external validity of these results.

Adult↗
PubMed1990

A secondary analysis of the School Health Education Evaluation data base.

This secondary analysis examined variables directly related to teacher training not fully examined in the School Health Education Evaluation (SHEE). The problem was to determine the effect of School Health Curriculum Project (SHCP) teacher training and curriculum implementation variables on overall student health knowledge, attitude, and self-reported practice scores in SHCP grades four-six. The major variables of interest had no statistically significant interactive effects on student scores in the knowledge, attitude, and practice domains. The teacher implementation variable had significant (p less than or equal to .05) main effects on student scores within attitude and practice domains in addition to statistically significant effects on related subscores within categorical item areas. Design flaws, which represent serious threats to internal and external validity of the primary analysis, may have effected results associated with this project.

Curriculum↗
PubMed1994

Hematologic, blood gas, blood chemistry and serum mineral values for a sample of clinically healthy adult goats.

Fifty-five hematologic, blood gas, blood chemistry, and serum mineral values were determined from a random sample of 29 clinically healthy goats from an equal number of randomly selected herds in the piedmont of North Carolina. Descriptive statistics and equations for calculated values are presented. The internal and external validity of the data is discussed.

Journal Article↗