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PubMed1995

[Methodological and statistical aspects of therapy evaluation exemplified by the Berlin psychotherapy study].

The answer to the question concerning the efficacy of psychotherapy is increasingly sought metaanalytically. For this purpose almost exclusively investigations are taken into consideration which have at least one control group. Using realistic data, the present paper refers to some basic considerations for the investigation and evaluation of therapeutic changes, which are however not always satisfyingly solved in metaanalytical studies. Investigations, therefore, especially of naturalistic samples, such as may be found in the context of outpatient or inpatient routine care, have a high clinical relevance for the evaluation of therapeutic changes even if they do not satisfy experimental requirements/standards. However, they do supplement experimental studies where the important aspect of external validity is concerned.

Germany↗

PubMed1994

Development of a cesarean delivery risk score.

OBJECTIVE: To explore the potential use of a risk score based on clinical risk factors related to cesarean delivery. METHODS: From a multivariate analysis of a large data set, clinical risk factors associated with nonelective cesarean delivery were used to develop a risk scoring system based on a summation of logistic coefficients corresponding to individual clinical risk factors. After development and evaluation of the system at one site with 1523 women, the model was back-tested for external validity against a total of 5994 deliveries at four unrelated sites. RESULTS: The scoring system showed a clear cutoff point of maximal sensitivity and specificity that corresponded to an overall value of 3, which appeared to be consistent among the sites studied. Using this cutoff value, cesarean delivery could be predicted with a sensitivity of 81% and a specificity of 57%. However, the positive predictive values based on this rating system were low. Negative predictive values were much higher, indicating that the scoring system was more useful in identifying women for whom cesarean delivery was unlikely. CONCLUSION: A simple risk scoring system for cesarean delivery based on individual clinical risk factors does not appear to be useful in predicting women at high risk for cesarean delivery. The cesarean risk score could have some value in identifying women at low risk for cesarean and for evaluating the use of resources for large populations of patients.

Cesarean Section↗

PubMedDate not supplied

Expanding child behavior management technology in pediatric dentistry: a behavioral science perspective.

Changing attitudes on the part of dentists and parents alike have resulted in increasing interest by dentists to develop additional child behavior management techniques. Collaborative research between dentists and behavioral psychologists has been encouraged by the American Academy of Pediatric Dentistry (AAPD) to address these concerns, but additional research is needed. This paper describes three techniques that, from a behavioral science perspective, offer promise for pediatric dentists managing disruptive children. In addition to scientific appeal, these techniques appear to have potential for acceptance and incorporation into the dental operatory. Although early research suggests these procedures can fit easily into routine practice, are time and cost efficient, and are relatively easy to learn, additional research is needed to clearly establish their external validity, cost efficiency, and ease of implementation. The discussion focuses on issues relevant to incorporating new technology into the dental school curriculum and disseminating it to practicing dentists.

Behavior Therapy↗

PubMed1993

Predicting outcome in papillary thyroid carcinoma: development of a reliable prognostic scoring system in a cohort of 1779 patients surgically treated at one institution during 1940 through 1989.

BACKGROUND: Multivariate analyses in papillary thyroid carcinoma (PTC) have shown that age, tumor size, local invasion and distant metastasis are independent predictive variables. This study attempted to define a reliable prognostic scoring system for predicting PTC mortality rates with 15 candidate variables that included completeness of primary tumor resection but excluded histologic grade and DNA ploidy. METHODS: The study group comprised 1779 patients with PTC (followed up for > 26,000 patient-years), divided by treatment dates into 1940 to 1964 (n = 764) and 1965 to 1989 (n = 1015). Cox model analysis and stepwise variable selection led to a prognostic model initially derived from the training set (n = 764). The initial prognostic score was thereafter validated externally with the later (1965 to 1989) "test" data set. RESULTS: The final model included five variables abbreviated by metastasis, age, completeness of resection, invasion, and size (MACIS). The final prognostic score was defined as MACIS = 3.1 (if aged < or = 39 years) or 0.08 x age (if aged > or = 40 years), + 0.3 x tumor size (in centimeters), +1 (if incompletely resected), +1 (if locally invasive), +3 (if distant metastases present). Twenty-year cause-specific survival rates for patients with MACIS less than 6, 6 to 6.99, 7 to 7.99, and 8+ were 99%, 89%, 56%, and 24%, respectively (p < 0.0001). CONCLUSIONS: Because the five variables needed for MACIS scoring are readily available after primary operation, such a prognostic system could have widespread applicability in assessment of PTC.

Aged↗

PubMed1993

Using a conceptual model for practice in a nursing wellness centre for seniors.

The use of a conceptual model to guide practice is critical to the maturation of the profession. Distinguishing between nursing and other health care professions rests, in part, on nursing's ability to articulate what it offers to clients. The nursing paradigm, comprising the essential components of the individual (client), health, environment, and nursing, provides general rules of thumb for the profession (Fawcett, 1984). Selecting a nursing model for a practice setting contributes to theory development: clinical questions generated from the model can be formulated as testable hypotheses. The Wellness Centre offers a unique opportunity for use of a conceptual model in a nurse-managed practice setting serving seniors. If conceptual models are to be useful, they need to be tested in the settings where nurses practise and for the roles that comprise nursing. Use of the crisis model, in this setting provides reality testing of the model which has evolved to a higher level of internal consistency and external validity as a direct result of practice.

Aged↗

PubMed1993

The significance of gender boundaries in preadolescence: contemporary correlates and antecedents of boundary violation and maintenance.

Previous research has established the importance of gender boundaries as a normative aspect of development in middle childhood. Here, the nature and importance of gender boundaries as an individual differences construct was explored. Ratings of gender boundary violation and gender boundary maintenance were made of 47 10-11-year-old children participating in a series of summer day camps. These ratings were supported by videotape-based behavior codings of gender boundary violating behaviors and by live observations of sheer number of associations with members of the opposite gender. In addition, considerable external validation of these individual differences was obtained. Children low on gender boundary violation and (especially) children high on boundary maintenance were independently judged by camp counselors to be socially competent. They also were found to be higher on a friendship variable, based on observation. Those who violated boundaries were especially unpopular with peers, based on a child interview. Finally, boundary violation and maintenance were related to attachment history and to early measures of parent-child generational boundary distortions.

Child↗

PubMed1993

[Evaluation of paradoxical interventions].

In anecdotal, uncontrolled case reports the threats to internal and external validity cannot be ruled out and the drawing of valid conclusions are prevented. These limits the usefulness of the "impressive" results of anecdotal case reports of paradoxical interventions. The few of controlled single case experimental and group designs permit valid conclusions and prove the efficacy of paradoxical interventions, but not their general superiority over other treatments. Meta-analysis also point to efficacy but not to the superiority of paradoxical interventions over other procedures. The combinations of paradoxical and behavioral procedures seem to enhance efficacy. What is missing in paradoxical treatment studies is the clear and detailed description of the specific interventions as well as the proof of the treatment's integrity. What is still unclear is the range of indications for paradoxical interventions, the clients' satisfaction and acceptability of the paradoxical interventions and ethical issues.

Behavior Therapy↗

PubMedDate not supplied

A portable datalogger to evaluate recall-based time-use measures.

Self-completed recall diaries have become a common tool in epidemiology and exposure assessment to determine the location and/or activities of subjects during study periods. Unfortunately, little effort has been made to determine the accuracy of such an approach for providing information without significant bias. It is usually assumed that subjects are truthful and complete in their recall. An electronic datalogger has been designed to allow subjects to record location changes as they occur in real time. Subjects carried the datalogger for 3-5 days and completed recall diaries at the end of each day. The concordance between the two records was found to be relatively good for the most commonly visited locations, e.g., bed/bath, workplace, etc. Poorer agreement was found for locations of short or infrequent visits, e.g., cellar or vehicle. The merits and shortcomings of the datalogger approach are discussed. While having external validation for recall diary records is clearly necessary, reliance on subject input to the datalogger presents its own problems related to subject compliance. Electronic approaches which do not require active subject input are recommended to aid in the evaluation of recall diaries.

Data Collection↗

PubMed1996

Therapy of idiopathic sudden sensorineural hearing loss. A review of the literature.

The literature on therapy of Idiopathic Sudden Sensorineural Hearing Loss (ISSHL) is reviewed. Clinical trails are judged on comparativeness, internal and external validity. It is concluded that steroids are only treatment available with a significant beneficial effect on ISSHL. Recommendations are made with regard to a well designed clinical trail on the treatment of ISSHL.

Acute Disease↗

PubMed1996

A critique of an evaluation of the impact of hospital bed closures in Winnipeg, Canada: lessons to be learned from evaluation research methods.

In the last few years, the continuing increases in health care expenditures have led to a call for greater accountability in health care and have spurred evaluative research into the area of health care policy. Yet the challenge has been to develop health care policy evaluations that maximize the rigor of the evaluation process within the constraints and limitations of evaluation milieus. This paper describes the principles of evaluation research and, using the example of a study evaluating the impact of hospital bed closures on community health status in Winnipeg, Canada, demonstrates the epistemological, methodological and interpretive problems that can occur when these principles are not followed. The conclusions are that studies which fail to outline the causal links between policy actions and outcomes, and use designs and methods which threaten internal and external validity, are limited in their abilities to elucidate the impact of health care policy changes.

Health Expenditures↗

PubMedDate not supplied

Correlates of compliance with measurement protocols in a Latino nutrition-intervention study.

INTRODUCTION: It is well known that attrition and noncompliance in longitudinal health intervention studies contribute to bias in both internal and external validity. However, little is known about rates and correlates of compliance with measurement protocols among Latinos. This article investigates correlates of compliance with follow-up physical measurement protocols among Latino subjects in a nutrition-oriented cardiovascular disease prevention program targeting low-English literate adults. METHODS: Correlates of compliance, measured at baseline, included four classes of variables: demographic characteristics, physical measures, health behaviors, and nutrition-related psychological variables. Subjects were categorized into one of three compliance groups: on-time compliers, late or "reluctant" compliers, and noncompliers. Approximately 36% of subjects complied on time, 25% complied late, and 39% did not comply. RESULTS: Analyses showed that, relative to on-time and late compliers, noncompliers tended to be male, younger, of lower income and Spanish-literacy level, to drink more alcohol, to be less physically active, and to have lower dietary fat avoidance scores. No significant differences were found for other factors considered (e.g., physical health measures). CONCLUSIONS: These results generally reflect those of non-Hispanics that indicate that individuals at greater "risk" are less likely to comply with study protocols. Such results may be useful for designing culturally appropriate cohort maintenance strategies for longitudinal studies with Latinos.

Adult↗

PubMed1998

A comparison of clustering solutions for cognitive heterogeneity in schizophrenia.

A cluster analytic solution based upon a battery of tests consisting of the Halstead Category and Tactual Performance Tests, the Trail Making Test, and the Wisconsin Card Sorting Test was compared with a solution based on the subtests of the Wechsler intelligence scales, utilizing a sample of 221 schizophrenic patients. Both analyses permitted four-cluster solutions, and we found a weak but significant degree of association between solutions. Examination of external validity of the two solutions revealed stronger associations with clinical variables for the Wechsler-scale-based solution. The major conclusions were that the existence of cognitive heterogeneity in schizophrenia exists across a broad range of abilities, and appears to reflect a combination of continuity of ability level and existence of possible subtypes requiring further neuropsychological and neurobiological verification.

Adult↗

PubMed1998

Parent personality traits and psychopathology associated with antisocial behaviors in childhood attention-deficit hyperactivity disorder.

Although a role for family and parent factors in the development of behavioral problems in childhood is often acknowledged, the roles of specific parental characteristics in relation to specific child actions need further elucidation. We studied parental "Big Five" personality traits and psychiatric diagnoses in relation to their children's antisocial diagnoses and naturalistically observed antisocial behaviors, in boys with and without the diagnosis of Attention-Deficit Hyperactivity Disorder (ADHD). First, regardless of comorbid antisocial diagnosis, boys with ADHD, more often than comparison boys, had mothers with a major depressive episode and/or marked anxiety symptoms in the past year, and fathers with a childhood history of ADHD. Second, compared to the nondiagnosed group, boys with comorbid ADHD + Oppositional Defiant or Conduct Disorder (ODD/CD) had fathers with lower Agreeableness, higher Neuroticism, and more likelihood of having Generalized Anxiety Disorder. Third, regarding linkages between parental characteristics and child externalizing behaviors, higher rates of child overt antisocial behaviors observed in a naturalistic summer program were associated primarily with maternal characteristics, including higher Neuroticism, lower Conscientiousness, presence of Major Depression, and absence of Generalized Anxiety Disorder. The association of maternal Neuroticism with child aggression was larger in the ADHD than in the comparison group. In contrast, higher rates of observed child covert antisocial behaviors were associated solely with paternal characteristics, including history of substance abuse and higher Openness. Results provide external validation in parent data for a distinction between overt and covert antisocial behaviors and support inclusion of parent personality traits in family studies. The interaction of maternal Neuroticism and child ADHD in predicting child aggression is interpreted in regard to a conceptualization of child by parent "fit."

Adult↗

PubMed1998

A meta-analysis of the relationship between social support and well-being.

This study focuses upon the relationship between social support and well-being and the effect size of social support on well-being. Meta-analysis was used to synthesize the primary research studies and a computer search was used in the preliminary examination of the literature. After this preliminary screening and narrowing of the search, approximately 150 research articles published after 1985 were reviewed. Totally, 21 primary studies met the inclusion criteria of this meta-analysis. This study indicated that 41 outcome variables were used in the 21 primary studies. Of these, seven outcome variables were categorized and named. Among these seven outcome variables, social support was significantly correlated with positive mood state, negative mood state, depression, level of functioning, and quality of life. Social support was not found to have a significant correlation at the .05 level of significance with perceived health status and physical symptoms. These findings have three implications: they facilitate external validity and generalization of research findings of the primary studies; they provide information on the magnitude of sample size for achieving statistical significance between social support and an outcome variable for future studies; and they provide information about social support intervention and enhancing the effect of social support on well-being.

Adult↗

PubMed1998

Use of image cytometry to classify biliary and ampullary adenocarcinomas.

OBJECTIVE: To create an objective classification system to perform TNM classification of ampullary adenocarcinoma and cholangiocarcinoma using image cytometric data derived from Feulgen-stained tumor nuclei. STUDY DESIGN: Surgically resected cases of ampullary adenocarcinoma and cholangiocarcinoma with established TNM classifications were selected on the basis of available formalin-fixed, paraffin-embedded tissue. Fifteen numerical variables related to morphometric, densitometric and textural features of each tumor nucleus were recorded. We employed a methodology based on multivariate statistical tools to characterize the association of morphonuclear variables with TNM classification. The first step consisted of identifying and selecting representative nuclei of each T class. From this "purified" data set an objective classification system was created. The classification system was assessed using internal and external validation. RESULTS: Employing ANOVA, all 15 variables were significantly associated with T classification, 11 of 15 with N and 4 with M. Multivariate analysis was employed to distinguish between T1, T2 and T3 lesions. Our methodology correctly classified 76% of T1 nuclei, 47% of T2 nuclei and 84% of T3 nuclei. Heterogeneity within an individual tumor was defined in 61% of cases included in the training set. Complete concordance between pathologic classification and the classification system was observed in 71% of an independent validation.

Adenocarcinoma↗

PubMed1998

The cardiovascular responses of male subjects to kung fu techniques. Expert/novice paradigm.

BACKGROUND: The primary aim was to assess cardiovascular responses of expert and novice subjects to kung fu techniques. It was hypothesised that experienced subjects would demonstrate improved economy of movement during the techniques, evidenced by reduced exercise intensity. METHODS EXPERIMENTAL DESIGN: a comparative design was established utilising two groups; experienced (group E), and novice (group N). SETTING: the experimentation took place under laboratory conditions, but was designed to maximise external validity. PARTICIPANTS: the only preselection variables were regular attendance at training and experience. Nine experienced males (group E, exp 9.5 +/- 5.2 yrs) and nine novice males (group N, exp 1.2 +/- 0.1 yrs) participated. The only exclusion guidelines were contraindications to participate within a maximal test, no subjects were excluded upon this basis. INTERVENTIONS: N/A. MEASURES: each subject participated in three kung fu protocols (forms, kicking and punching). Each protocol, randomly allocated, consisted of ten work (30 sec) and ten rest periods (30 sec). MEASURES taken during the protocols were heart rate (HR) and oxygen consumption (VO2). These were expressed as a percentage of maximal values to reflect exercise intensity. RESULTS: During both the form protocol and punching protocol group E were found to be working at a significantly (p < 0.05) lower % VO2 max than group N (forms--group E = 71.5 +/- 5.3, group N = 82.1 +/- 6.1; punching--group E = 37.5 +/- 2.1, group N = 40.6 +/- 2.6, p < 0.05). This suggests that experienced subjects were more economical when performing similar movement patterns. CONCLUSIONS: It was concluded that cardiovascular responses to kung fu techniques differ depending upon experience level. It is difficult to directly relate this to improved economy since work output could not be accurately quantified. It was also found that kung fu protocols elicited exercise intensity into the cardiovascular training zone.

Adult↗

PubMedDate not supplied

Translation and validation of the danish version of the Bournemouth questionnaire.

OBJECTIVE: Translation, cultural adaptation, and validation of the Danish version of the Bournemouth Questionnaire (BQ). METHODS: Translation/retranslation of the English version of the BQ was done blindly and independently by 4 different individuals and adapted by an expert team. The Danish version of the BQ was tested for face validity in a sample of low-back pain (LBP) patients attending 2 chiropractic clinics. Reproducibility was tested using 28 stable LBP patients attending a hospital outpatient back-pain clinic. Finally, the Danish version of the BQ was tested for external construct validity, external longitudinal construct validity, internal consistency, and sensitivity to change against the Danish versions of the SF-36 and the Roland-Morris Disability Questionnaire (RMDQ) using 118 first-time LBP patients reporting to 1 of 7 chiropractic clinics. RESULTS: Minor changes were made after the face-validity test. Intraclass correlation coefficient of the total score for the BQ based on the 2 administrations was 0.96. Satisfactory values for the external construct validity and the external longitudinal construct validity were found using both Pearson r and Bland-Altman plots. Cronbach alpha's were .89 and .88 for the pretreatment and posttreatment scores, respectively. The Danish version of the BQ showed greater responsiveness than the SF-36 and similar responsiveness when compared with the RMDQ. CONCLUSIONS: The BQ was successfully translated and culturally adapted into Danish. The BQ was successfully tested for validity, consistency, and responsiveness against the Danish version of the SF-36 and RMDQ.

Denmark↗

PubMed2006

Prediction model of hepatocarcinogenesis for patients with hepatitis C virus-related cirrhosis. Validation with internal and external cohorts.

BACKGROUND/AIMS: To estimate hepatocarcinogenesis rates in patients with hepatitis C virus (HCV)-related cirrhosis, an accurate prediction table was created. METHODS: A total of 183 patients between 1974 and 1990 were assessed for carcinogenesis rate and risk factors. Predicted carcinogenesis rates were validated using a cohort from the same hospital between 1991 and 2003 (n=302) and an external cohort from Tokyo National Hospital between 1975 and 2002 (n=205). RESULTS: The carcinogenesis rates in the primary cohort were 28.9% at the 5th year and 54.0% at the 10th year. A proportional hazard model identified alpha-fetoprotein (>or=20 ng/ml, hazard ratio 2.30, 95% confidence interval 1.55-3.42), age (>or=55 years, 2.02, 95% CI 1.32-3.08), gender (male, 1.58, 95% CI 1.05-2.38), and platelet count (<100,000 counts/mm3, 1.54, 95% CI 1.04-2.28) as independently associated with carcinogenesis. When carcinogenesis rates were simulated in 16 conditions according to four binary variables, the 5th- and 10th-year rates varied from 9 to 64%, and 21-93%, respectively. Actual carcinogenesis rates in the internal and external validation cohorts were similar to those of the simulated curves. CONCLUSIONS: Simulated carcinogenesis rates were applicable to patients with HCV-related cirrhosis. Since, hepatocarcinogenesis rates markedly varied among patients depending on background features, we should consider stratifying them for cancer screening and cancer prevention programs.

Adult↗