Stage of change, decisional balance, and temptations for smoking: measurement and validation in a large, school-based population of adolescents.

Developing interventions for reducing adolescent smoking rates based on the Transtheoretical Model (TTM) requires the development of quality measures of the key constructs of the model. The goal of this investigation was to evaluate the psychometric properties of measures of Stage of Change, Decisional Balance and Situational Temptation for both smokers and nonsmokers and to test if the predicted relationships between these constructs were confirmed in a large (N=2808) sample of adolescents. A correlated three factor model (Social Pros, Coping Pros and Cons) provided an excellent fit to the 12-item Decisional Balance inventory for both smokers (CFI=0.957) and nonsmokers (CFI=0.963). A hierarchical four factor model (negative affect, positive social, habit strength and weight control) provided an excellent fit to the eight-item Situational Temptations inventory for smokers (CFI=0.969). A hierarchical five-factor model (same four as smokers plus Curiosity) provided an excellent fit to the 10-item Situational Temptations inventory for nonsmokers (CFI=0.943). The relationships between both the Decisional Balance and temptation scales and the Stages of Change were verified for both smokers and nonsmokers. The measures for adolescents are similar to but not the same as the measures of these constructs for adults.

Validation of decisional balance and situational temptations measures for dietary fat reduction in a large school-based population of adolescents.

Brief, validated, and reliable theory-based measures specifically designed for use in large survey research with adolescent populations are needed to assess attitudes and behaviors about dietary fat consumption. This study validated two transtheoretical model (TTM)-based instruments in 2639 ninth graders from 12 Rhode Island high schools. The Decisional Balance Questionnaire for Adolescent Dietary Fat Reduction (DBQA) measures the importance adolescents assign to the pros and cons of reducing dietary fat consumption, while the Situational Temptations Questionnaire for Adolescents (STQA) measures temptations to eat high-fat foods as both a global construct and across three categories of challenging situations. Four competing models were compared for each instrument. An eight-item, correlated two-factor Pros and Cons model was validated for the decisional balance measure and a nine-item, three-factor hierarchical model was validated for situational temptations. The theoretically predicted relationships between stage of change and the pros and cons, as well as stage and situational temptations were supported. These results demonstrate that both measures have sound psychometric properties and are externally valid.

Use of the anti-idiotype antibody vaccine TriAb after autologous stem cell transplantation in patients with metastatic breast cancer.

Between April 1997 and March 1998 we evaluated the immune response and outcome in 11 chemosensitive patients who were treated with the anti-idiotype antibody vaccine TriAb after recovery from intensive therapy and autologous stem cell transplant (ASCT). Triab was commenced after recovery from the acute effects of ASCT; a minimum interval of 1 month was required from completion of consolidation radiotherapy, if given. Nine patients (82%) manifest anti-anti-idiotype antibody (Ab3) responses post ASCT. The maximal Ab3 response was seen after a median of 10 doses (range 5-20), which corresponded to a median of 14 months (range 5-19) post ASCT. Evidence of a T cell proliferative response was seen in eight patients; the response was modest in most of these. At a median follow-up of 24 months (range 22-33) after ASCT, four patients are alive without evidence of disease progression. All four of these patients were in the subgroup with more vigorous immune responses. Subsequent efforts have been directed toward the achievement of higher levels of immune responses more rapidly post ASCT. Bone Marrow Transplantation (2000) 26, 729-735.

Time series analysis in historiometry: a comment on Simonton.

Time series analysis (TSA) is one of a number of new methods of data analysis appropriate for longitudinal data. Simonton (1998) applied TSA to an analysis of the causal relationship between two types of stress and both the physical and mental health of George III. This innovative application demonstrates both the strengths and weaknesses of time series analysis. Time series is applicable to a unique class of problems, can use information about temporal ordering to make statements about causation, and focuses on patterns of change over time, all strengths of the Simonton study. Time series analysis also suffers from a number of weaknesses, including problems with generalization from a single study, difficulty in obtaining appropriate measures, and problems with accurately identifying the correct model to represent the data. While careful attempts are made to minimize these problems, each is present in the Simonton study, although sometimes in a subtle manner. Changes in how the data could be gathered are suggested that might help to solve some of these problems in future studies. Finally, the advantages and disadvantages of employing alternative methods for analyzing multivariate time series data, including dynamic factor analysis, are discussed.