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PubMed2005

Replication of subtypes for smoking cessation within the Preparation stage of change.

OBJECTIVE: Recent cluster analyses based on the Pros and Cons and the Situational Temptations measures performed within the stages of change defined by the Transtheoretical Model have suggested the existence of distinct cluster subtypes. The goal of this study is to replicate cluster subtypes within the Preparation stage of change in a secondary analysis of data from a sample of current smokers (N=3967). Identification of stable cluster subtypes would permit the development of tailored interventions focusing on these subtypes. METHOD: Two random samples of approximately 340 subjects were selected from the 686 participants in the Preparation stage. The cluster analyses were performed using the Pros, Cons and Situational Temptations. Interpretability of the pattern, pseudo F test, and dendograms were used to determine the number of clusters. RESULTS: Four distinct cluster subtypes (Classic, Progressing, Early Preparation, and Disengaged) were found and replicated across samples. The clusters were externally validated using the ten processes of change and two smoking behavior variables. Statistically significant (p<0.05) multivariate effects were found for the ten processes of change and the smoking behavior variables (p<0.001) in the two samples. CONCLUSIONS: The cluster patterns replicate earlier findings and provide evidence for the existence of clusters subtypes within the Preparation stage of change.

Adaptation, Psychological↗
PubMed2005

Replication of subtypes for smoking cessation within the precontemplation stage of change.

The Transtheoretical Model constructs have been used in the development of effective tailored interventions for smoking cessation. Recent studies have suggested the existence of clusters within each stage of change, based on measures of the Pros, Cons and the Situational Temptations. The goal of this study is to replicate cluster subtypes within the Precontemplation stage of change in a secondary analysis of data from a sample of current smokers (N=3967). Four random samples ranging from 312 to 400 participants were selected from the Precontemplators subgroup. The cluster analyses were performed using Ward's Method on the standard scores from the three scales. Interpretability of the pattern, pseudo F test, and dendograms were used to determine the number of clusters. Four cluster subtypes were found and replicated across samples. The ten processes of change and two smoking behavior variables were used in the external validation of clusters. Statistically significant multivariate effects were found for the processes of change (p<.05) and the smoking behavior variables (p<.001) in all samples. The cluster patterns closely replicate earlier findings and provide evidence for the existence of clusters subtypes within the Precontemplation stage of change.

Adaptation, Psychological↗
PubMed2006

Psychometric evaluation of the smoking cessation Processes of Change scale in an adolescent sample.

The Processes of Change are the cognitions, behaviors, and emotions that people employ to change their behaviors. However, the processes of change remain the least studied dimension of the transtheoretical model. The present study presents a psychometric evaluation of the short form of the processes of change inventory for smoking cessation in an adolescent sample of 798 ninth-grade smokers from 22 Rhode Island high schools. The majority of the sample was white (87.2%), split approximately evenly as regards to gender (48.1% female), with an average age of 14.3 (SD=0.6) years of age. The same hierarchical model established on the adult sample was fit to the 20-item inventory. This model included 10 primary factors representing the processes of change and two second order factors that grouped the processes into five behavioral and five experiential processes of change. Model fit indices (RMSEA=0.08, CFI=0.92) supported the hypothesized structure. External validation was established by testing for stage differences in the use of the ten processes. A significant MANOVA (F(4,793)=18.517, p<0.001) and separate ANOVAs demonstrated that the use of all ten processes increased across the stages, as predicted by the transtheoretical model of behavior change. The processes of change help guide researchers, clinicians, and intervention program developers towards effective strategies to assist individuals at all stages of change progress towards healthier behaviors.

Adolescent↗
PubMed2006

Postpartum return to smoking: identifying different groups to tailor interventions.

OBJECTIVE: (a) To describe a population-based sample of women postpartum who smoked before pregnancy on grounds of the perceived advantages and disadvantages of nonsmoking and the self-efficacy not to smoke. (b) To identify grouping characteristics that can differentiate among those women. This could lead to the development of intervention strategies that are of different efficacy depending on the cluster the woman is member of. SAMPLE: A population-based sample of 317 women who had smoked at the beginning of pregnancy and who were smoke-free at the time of giving birth. DATA: Data about the acquisition stages of change to restart smoking, the perceived advantages of nonsmoking and the self-efficacy to remain smoke free on grounds of the Transtheoretical Model of Behavior Change was assessed. Smoking status was assessed 12 months later. STATISTICAL ANALYSIS: A cluster analysis was used to identify different groups; a logistic regression was calculated to assure the external validity of the clusters identified. RESULTS: The acquisition stages of change do not fit the situation of nonsmoking women postpartum in Germany, but four different clusters of ex-smoking women postpartum were identified on grounds of the other TTM-constructs. These are: the protected, the high risk, the premature and the ambivalent group. The clusters are associated with relapse after 12 months, none of the other variables controlled for was statistically significant. CONCLUSIONS: The TTM contributes to a better understanding of nonsmoking women postpartum. Further studies have to replicate the clusters found and have to find whether interventions tailored to these clusters are more effective in preventing relapse than other interventions.

Adolescent↗
PubMed2006

Identifying cluster subtypes for the prevention of adolescent smoking acquisition.

School-based smoking prevention programs are typically identical for all students. Tailoring prevention materials to focus on individual needs with an emphasis on students at highest risk is a promising alternative. Recent prevention programs have tailored materials based on the Stages of Acquisition, an extension of the Stages of Change used to tailor smoking cessation materials effectively for adults. Three stages of acquisition have been identified: Acquisition Precontemplation (aPC), Acquisition Contemplation (aC) and Acquisition Preparation (aPR). However, about 90% of nonsmoking adolescents classify themselves in the aPC stage. A cluster analysis was performed, using the Decisional Balance and Situational Temptations scales, for three random subsamples of adolescents within the aPC stage (N(1)=N(2)=N(3)=514). Four distinct subtypes were identified in each subsample: High Risk, Protected, Ambivalent, and Risk Denial. External validity was established using family support for nonsmoking, peer variables, and stage classification at follow-up assessment (12, 24, and 36 months). Family support for nonsmoking was related to subtype much more strongly than peer interactions. Subjects in the Protected subgroup were the most likely to remain in the aPC stage at each follow-up assessment. Subtype membership, along with membership in the aC and aPR stages, provides important additional information for tailoring smoking prevention materials. Tailored interventions can focus on those adolescents at highest risk and limit or avoid expending resources on those at very low risk.

Adolescent↗
PubMed2005

Influence of clinical trial enrollment on the quality of care and outcomes for patients with non-ST-segment elevation acute coronary syndromes.

BACKGROUND: Clinical trials provide evidence that is formulated into recommendations for practice guidelines, but it remains uncertain whether patients enrolled in trials are similar to those treated in routine practice and whether trial enrollment influences inhospital treatments and outcomes. METHODS: Using data from the CRUSADE quality improvement initiative, we evaluated predictors of trial enrollment, treatment patterns, and clinical outcomes among high-risk patients with non-ST-segment elevation acute coronary syndromes (NSTE ACS) who were and were not enrolled in a clinical trial during hospitalization. RESULTS: Among 55,172 high-risk patients presenting with NSTE ACS at 443 US hospitals, 1397 (2.5%) patients were enrolled in a clinical trial during index hospitalization. Significant predictors of trial enrollment included male sex, lack of renal insufficiency, and absence of congestive heart failure on presentation. Acute (<24 hours) and discharge secondary prevention interventions recommended by the American College of Cardiology/American Heart Association guidelines for NSTE ACS were used more commonly in patients enrolled in clinical trials. Cardiac catheterization (84.5% vs 65.8%, P < .0001), percutaneous coronary intervention (48.2% vs 36.3%, P < .0001), and bypass surgery (19.1% vs 11.3%, P < .0001) were also performed more frequently in trial patients. The adjusted risk of inhospital mortality was similar in trial versus nontrial patients (odds ratio 0.86, 95% CI 0.60-1.24). CONCLUSIONS: Patients with NSTE ACS participating in clinical trials are more likely to receive beneficial therapies and interventions throughout hospitalization, but preferential recruitment of patients with lower-risk features may limit the external validity of trial results.

Acute Disease↗
PubMed2004

The study designed by a committee: design of the Multisite Violence Prevention Project.

This article describes the research design of the Multisite Violence Prevention Project (MVPP), organized and funded by the National Center for Injury Prevention and Control (NCIPC) at the Centers for Disease Control and Prevention (CDC). CDC's objectives, refined in the course of collaboration among investigators, were to evaluate the efficacy of universal and targeted interventions designed to produce change at the school level. The project's design was developed collaboratively, and is a 2 x 2 cluster-randomized true experimental design in which schools within four separate sites were assigned randomly to four conditions: (1) no-intervention control group, (2) universal intervention, (3) targeted intervention, and (4) combined universal and targeted interventions. A total of 37 schools are participating in this study with 8-12 schools per site. The impact of the interventions on two successive cohorts of sixth-grade students will be assessed based on multiple waves of data from multiple sources of information, including teachers, students, parents, and archival data. The nesting of students within teachers, families, schools and sites created a number of challenges for designing and implementing the study. The final design represents both resolution and compromise on a number of creative tensions existing in large-scale prevention trials, including tensions between cost and statistical power, and between internal and external validity. Strengths and limitations of the final design are discussed.

Adolescent↗
PubMed2006

Using RE-AIM metrics to evaluate diabetes self-management support interventions.

BACKGROUND: Current healthcare evidence relies on relatively narrow efficacy data to make decisions about program impact. This paper illustrates the application of impact indices derived from the RE-AIM (reach, effectiveness, adoption, implementation, and maintenance) framework that takes a broader perspective and includes issues important to decision makers, such as reach, adoption, and cost. METHODS: Composite RE-AIM indices that summarize impact and cost efficiency at the individual participant and setting levels are used to compare two different diabetes self-management support approaches. One study, the Diabetes Priority (DP) program, involved 886 diabetes patients from 30 primary care offices, and relied on usual clinical staff for program implementation. The other study, Diabetes Health Connection (DHC), involved 335 diabetes patients in both HMO and fee-for-service settings, and used health education staff. RESULTS: The DP performed better on the setting-level impact index, but the programs produced similar results on individual-level impact. The DP had a greater reach (50% vs 38%); was more effective at the initial follow-up (median effect size [ES]=0.23 vs 0.17); and had greater impact consistency across various populations. The DHC performed better on several indices, including higher physician office adoption (20% vs 6%) and staff adoption (79% vs 70%), and there was less variability among intervention staff on protocol implementation (median ES=0.0 vs 0.50). CONCLUSIONS: Greater use of indices focused on public health and external validity criteria could help identify programs most likely to have a meaningful impact on population health and to fit local settings and priorities.

Attitude of Health Personnel↗
PubMed2006

Methodologic challenges in disseminating evidence-based interventions to promote physical activity.

During the past decade, numerous intervention studies have been published on the effectiveness of programs to promote active living; however, few studies have addressed the dissemination of effective physical activity interventions. Both community settings and healthcare settings are important locations for dissemination of evidence-based programs and policies. A major gap in the existing literature involves the appropriate methodologic approaches for planning, evaluating, and reporting on dissemination efforts for effective and promising interventions in these locations. To address this gap, two hypothetical dissemination studies are presented: a quasi-experimental study of local health agencies (Scenario 1) and a group-randomized trial of clinical practices (Scenario 2). These studies help to elucidate the barriers and opportunities for implementing evidence-based physical activity interventions across different settings. Based on the scenarios, the existing literature, and the authors' experience, dissemination challenges that researchers and practitioners may experience (i.e., issues of design, measures of outcomes and external validity, the balance between fidelity and adaptation to local settings, and the review and funding of dissemination science) are discussed. Researchers, practitioners, and policymakers are invited to address the issues outlined in this article in order to bridge the gap between the generation of new knowledge on efficacious physical activity interventions and widespread application of these approaches in community and clinical settings.

Community Health Services↗
PubMed2006

Ancillary studies in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) Trial: Synergies and opportunities.

The definitive power of randomized controlled trials (RCTs) to characterize the efficacy of putative therapeutic approaches cannot be overestimated. Such trials are expensive, and their implementation requires prolonged and intensive commitments by both investigators and subjects. Accordingly, enhancing their value, in a sense increasing the "scientific return on investment," is a laudatory objective. Ancillary studies afford a great opportunity to do so. They permit acquisition of new knowledge, elucidation of cause/consequence relation, and delineation of pathogenetic mechanisms at a much lower cost than would be possible if they were performed independently of the parent RCTs. In addition, their utility is enhanced by internal consistency under the rubric of the parent trial and the presumed external validation of the parent trial. Several ancillary studies undertaken in conjunction with the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial provide cogent examples. They seek to delineate causal connections linking the accelerated coronary disease typical of diabetes with phenomena such as genetic predisposition to altered expression of cytokines and fibrinolytic system proteins, inflammation, procoagulation, insulin-induced impairment of fibrinolysis, insulin resistance, and the response to insulin-sensitizing and insulin-providing treatment strategies.

Angioplasty, Balloon, Coronary↗
PubMed2004

Interpretations and attitudes toward healthy eating among Japanese workers.

Japanese interpretations of 'healthy eating' may differ from those of people in other industrialized countries; however, no studies have addressed this question. Thus, we examined how Japanese people interpret healthy eating and investigated the factors relevant to that interpretation. In the first study, in order to investigate lay interpretations of the meaning of healthy eating, 34 adults were interviewed, and the results were analyzed as a basis for the second study. In the second study, a sample of city workers (n=1155) in Japan responded to a questionnaire concerning attitudes toward healthy eating, and relevant factors were assessed by a factor analysis. We made three findings. (1) Japanese adults interpreted 'eating a nutritionally balanced diet' and 'eating plenty of vegetables' as the most important definitions of healthy eating. (2) Healthy eating included two factors according to the factor analysis of questionnaire responses: 'eating styles and habits' and 'foods and nutrition.' (3) The relevant characteristics of the subjects regarding the two factors differed. Although these findings are unique, the external validity of this study is limited. More research is necessary to verify the present results.

Adult↗
PubMed2026

Multimodal intervention benefits: Responder analysis of J-MINT PRIME Kanagawa trial.

INTRODUCTION: The J-MINT PRIME Kanagawa trial was an 18-month multimodal intervention (incorporating exercise, nutrition, and metabolic management) for dementia prevention. Because the primary analysis showed no significant benefits, we performed an exploratory responder analysis to identify responsive subpopulations. METHODS: We analyzed the Full Analysis Set comprising 188 participants. Classification and regression tree (CART) analysis, applied to the intervention arm, identified baseline predictors of cognitive improvement. These rules were then applied to the entire cohort to evaluate treatment effects on the Mini-Mental State Examination (MMSE) using fully adjusted mixed-effects models for repeated measures (MMRM). RESULTS: CART identified a "Target Group" (N = 108) characterized by baseline profiles such as an MMSE score < 28 or specific metabolic ranges (e.g., LDL-C < 135 mg/dL). Within this target group, the intervention significantly preserved MMSE trajectories compared with the control group (group &#xd7; time interaction, P = 0.022). In contrast, the Non-Target Group (N = 80), consisting of high-functioning individuals (MMSE &#x2265; 28), exhibited no significant group &#xd7; time interaction. DISCUSSION: Multimodal interventions may effectively preserve global cognition in older adults with sub-threshold cognitive decline. Careful targeting of appropriate populations, while considering potential longitudinal measurement artifacts (e.g., practice effects), is essential. These findings provide a hypothesis-generating framework that warrants external validation in future prevention trials.

Humans↗
PubMed2026

Beyond multidimensionality: a systematic review of recurrent frailty archetypes in community-dwelling older adults.

BACKGROUND: Frailty is a clinically heterogeneous geriatric syndrome commonly summarised using physical or multidomain severity scores. Whether person-centred analyses identify recurring within-frailty configurations has not been systematically examined in community-dwelling older adults. METHODS: We searched PubMed, Embase, MEDLINE, and CINAHL (January 2000-November 2025) for cross-sectional studies using latent class, latent profile, or analogous clustering methods to derive frailty subgroups. Quality was assessed using the AHRQ checklist and a purpose-built appraisal of person-centred model reporting. Study-derived classes were mapped in duplicate to a structured archetype framework developed through comparison of class-defining features across studies. RESULTS: Fourteen reports representing 12 independent datasets from eight countries were included. Six configurations were identified: minimally impaired reference, mobility-physical, nutritional-metabolic, cognitive-predominant, combined cognitive-physical, and psychosocial/mood-predominant. Convergence was measurement-dependent. The reference and mobility-physical configurations recurred across physical-only and multidomain indicator sets, while the combined cognitive-physical configuration appeared across several multidomain frameworks but required cognition to be measured. The remaining configurations emerged only when their defining domains were included. Evidence of prognostic value beyond aggregate frailty severity came from one deficit-index study. Collapsing shared-provenance reports and excluding the boundary-eligible study did not alter recurrence; excluding the Croatian dataset left five configurations recurrent, with the cognitive-predominant configuration supported by one independent dataset. CONCLUSIONS: Person-centred analyses identify recurring within-frailty configurations, but their apparent stability is partly measurement-dependent. A five-configuration core persisted after exclusion of the Croatian dataset, whereas the cognitive-predominant configuration remained weakly replicated. Harmonised indicators and rigorous external validation are needed before clinical application.

Humans↗
PubMed2006

Hospital volume and inpatient mortality outcomes of total hip arthroplasty in the United States.

The purpose of this study was to examine the effect of hospital volume on outcomes for primary and revision total hip arthroplasty (THA). The Nationwide Inpatient Sample database was used to identify our patient set. These data include a sample of non-Medicare and Medicare patients who are unique to this study, increasing external validity compared with other studies. Outcome variables examined included in-hospital mortality and prolonged length of stay (PLOS). Primary THA mortality was 0.16% in the highest volume quartile and 0.29% in the lowest volume quartile (P < .001). The rates of PLOS showed improved outcomes in the highest volume hospitals. Similar trends were found for revision THA, with an in-hospital mortality of 1.20% for lowest volume hospitals and 0.48% for highest volume hospitals (P < .001). Hospitals with higher volume had superior inpatient outcomes mortality, PLOS, and discharge disposition for THA and revision arthroplasty.

Arthroplasty, Replacement, Hip↗
PubMed2005

Analyzing aphasia data in a multidimensional symptom space.

The utility of single-case vs. group studies has been debated in neuropsychology for many years. The purpose of the present study is to illustrate an alternative approach to group studies of aphasia, in which the same symptom dimensions that are commonly used to assign patients to classical taxonomies (fluency, naming, repetition, and comprehension) are used as independent and continuous predictors in a multivariate design, without assigning patients to syndromes. One hundred twenty-six Italian-speaking patients with aphasia were first classified into seven classic aphasia categories, based on fluency, naming, auditory comprehension, and repetition scales. There were two goals: (1) compare group analyses based on aphasia types with multivariate analyses that sidestep classification and treat aphasic symptoms as continuous variables; (2) present correlation-based outlier analyses that can be used to identify individuals who occupy unusual positions in the multivariate "symptom space." In the service of the first goal, group performance on an external validation measure (the Token Test) was assessed in three steps: analyses of variance based on aphasia type, regressions using the same cut-offs for fluency, naming, comprehension and repetition as independent but dichotomous predictors, and regressions using the same subscales as continuous predictors (with no cut-offs). More variance in Token Test performance was accounted for when symptoms were treated as continuous predictors than with the other two methods, though use of independent but dichotomous predictors accounted for more variance than aphasia taxonomies. Thus, if we by-pass classical taxonomies and treat patients as points in a multidimensional symptom space, better predictions are obtained. Outlier analyses show that group results depend on heterogeneity among patients, which can be used as a search tool to identify potentially interesting dissociations. Hence this multivariate group approach is complementary to and compatible with single-case methods.

Aphasia↗
PubMed2006

Diagnosing benign and malignant lesions in breast tissue sections by using IR-microspectroscopy.

The collection of IR spectra through microscope optics and the visualization of the IR data by IR imaging represent a visualization approach, which uses infrared spectral features as a native intrinsic contrast mechanism. To illustrate the potential of this spectroscopic methodology in breast cancer research, we have acquired IR-microspectroscopic data from benign and malignant lesions in breast tissue sections by point microscopy with spot sizes of 30-40 microm. Four classes of distinct breast tissue spectra were defined and stored in the data base: fibroadenoma (a total of 1175 spectra from 14 patients), ductal carcinoma in situ (a total of 1349 spectra from 8 patients), connective tissue (a total of 464 spectra), and adipose tissue (a total of 146 spectra). Artifical neural network analysis, a supervised pattern recognition method, was used to develop an automated classifier to separate the four classes. After training the artifical neural network classifier, infrared spectra of independent external validation data sets ("unknown spectra") were analyzed. In this way, all spectra (a total of 386) taken from micro areas inside the epithelium of fibroadenomas from 4 patients were correctly classified. Out of the 421 spectra taken from micro areas of the in situ component of invasive ductal carcinomas of 3 patients, 93% were correctly identified. Based on these results, the potential of the IR-microspectroscopic approach for diagnosing breast tissue lesions is discussed.

Breast Neoplasms↗
PubMed2005

Structure activity relationships and quantitative structure activity relationships for the flavonoid-mediated inhibition of breast cancer resistance protein.

Breast cancer resistance protein (BCRP) is a newly identified ABC transporter, which plays an important role in drug disposition and represents an additional mechanism for the development of MDR. Flavonoids, a major class of natural compounds widely present in foods and herbal products, have been shown to be BCRP inhibitors. The objective of the present study was to elucidate the SAR and derive a QSAR model for flavonoid-BCRP interaction. The EC(50) values for increasing mitoxantrone accumulation in MCF-7 MX100 cells for 25 flavonoids, from five flavonoid subclasses, were determined in this study or obtained from our previous publication [Zhang S, Yang X, Morris ME. Combined effects of multiple flavonoids on breast cancer resistance protein (ABCG2)-mediated transport. Pharm Res 2004;21(7):1263-73], and ranged from 0.07+/-0.02 microM to 183+/-21.7 microM. We found that the presence of a 2,3-double bond in ring C, ring B attached at position 2, hydroxylation at position 5, lack of hydroxylation at position 3 and hydrophobic substitution at positions 6, 7, 8 or 4', are important structural properties important for potent flavonoid-BCRP interaction. These structural requirements are similar but not identical to those for potent flavonoid-NBD2 (P-glycoprotein) interaction, indicating that inhibition of BCRP by flavonoids may involve, in part, the binding of flavonoids with the NBD of BCRP. In addition, a QSAR model consisting three structural descriptors was constructed, and both internally and externally validated, suggesting the model could be used to quantitatively predict BCRP inhibition activity of flavonoids. These findings should be useful for predicting BCRP inhibition activity of other untested flavonoids and for guiding the synthesis of potent BCRP inhibitors for potential clinical application.

ATP Binding Cassette Transporter, Subfamily G, Mem↗
PubMed2005

Testing resource value in group-housed animals: an investigation of cage height preference in laying hens.

To avoid unpredictable social effects, animals' behavioural priorities are almost always tested using individuals housed singly, yet many species kept commercially are social animals housed in groups. Our aim was to develop a method of investigating environmental preference in group-housed laying hens, Gallus gallus domesticus, that maximised the external validity of our findings. In a simple test of preference, eight groups of ten hens were given free choice between furnished cages with minimum heights of 38 cm (low) and 45 cm (high). A preference for one cage height over the other would be evident as a shift from a binomial distribution of flock sizes in the two cages. No height preference was found as hens distributed evenly between the two cages more frequently than was expected. This suggests at high stocking densities maximising average inter-individual distance could be a priority over increased cage height. In a second experiment, to investigate the value that hens placed on a change in cage height; a 'cost' in the form of a narrow gap was imposed on movement from a low or high start cage to a high or low target cage, respectively. Cage height did not influence the latency of the first three hens to enter the target cage. However, latencies for subsequent hens were shorter and more hens worked to access a high target cage than a low target cage. We suggest that titrating animals' willingness to tolerate higher stocking densities against access to a resource could be an effective way to compare responses of group-housed animals to resources that are expected to satisfy the same motivational state.

Animal Welfare↗