Focus on Autism and Other Developmental Disabilities, 2005
Characteristics of persons with autism and other developmental disabilities may make this populat... more Characteristics of persons with autism and other developmental disabilities may make this population especially vulnerable to the effects of stress. Prior research on stress and its measurement in this population is reviewed. Using a single-case multielement design, this study explores the feasibility of measuring cardiovascular responses to four stressors in 10 individuals (age 13 to 37 years) with autism and other developmental disabilities. Results suggest that assessing cardiovascular responses is a viable procedure for identifying individual differences in reactivity to specific environmental stressors. Implications of this research and future directions for assessment are discussed.
This study evaluated how well predictions from the transtheoretical model (TTM) generalized from ... more This study evaluated how well predictions from the transtheoretical model (TTM) generalized from smoking to diet. Longitudinal data were used from a randomized control trial on reducing dietary fat consumption in adults (n 51207) recruited from primary care practices. Predictive power was evaluated by making a priori predictions of the magnitude of change expected in the TTM constructs of temptation, pros and cons, and 10 processes of change when an individual transitions between the stages of change. Generalizability was evaluated by testing predictions based on smoking data. Three sets of predictions were made for each stage: Precontemplation (PC), Contemplation (C) and Preparation (PR) based on stage transition categories of no progress, progress and regression determined by stage at baseline versus stage at the 12-month follow-up. Univariate analysis of variance between stage transition groups was used to calculate the effect size [omega squared (x 2 )]. For diet predictions based on diet data, there was a high degree of confirmation: 92%, 95% and 92% for PC, C and PR, respectively. For diet predictions based on smoking data, 77%, 79% and 85% were confirmed, respectively, suggesting a moderate degree of generalizability. This study revised effect size estimates for future theory testing on the TTM applied to dietary fat.
The most common criteria recommended by philosophers of science for evaluating theories were orga... more The most common criteria recommended by philosophers of science for evaluating theories were organised within a hierarchy ranging from the least to the most risky tests for theories of health behavior change. The hierarchy progressed across: (1) Clarity; (2) Consistency; (3) Parsimony; (4) Testable; (5) Predictive Power; (6) Explanatory Power; (7) Productivity; (8) Generalisable; (9) Integration; (10) Utility; (11) Efficacy; and (12) Impact. The hierarchy was applied to the Transtheoretical Model (TTM) as an example of a health behavior change theory. The application was from the perspective of critics and advocates of TTM. Examples of basic and applied research challenging and supporting TTM across the hierarchy of criteria are presented. The goal is to provide a model for comparing alternative theories and to evaluate progress across the hierarchy within a particular theory. As theories meet criteria at each step in the hierarchy, the research and applications they generate can have increasing impacts on the science and practice of health behavior change.
Despite the hypothesized link between arousal and behavior in persons with autism, there is a lac... more Despite the hypothesized link between arousal and behavior in persons with autism, there is a lack of idiographic research that directly assesses arousal responses to novel stimuli or social situations in this population. The current study used heart rate as a measure of sympathetic activity to compare arousal responses to the presentation of potentially stressful situations in five persons with autism and five age-and sex-matched typically developing individuals. Findings revealed that the group with autism showed significant responses to stressors only 22% of the time compared to the typically developing group, which showed significant responses 60% of the time. Interpretation of these results and methodological considerations for future research on arousal in persons with autism are discussed.
Despite a specific need for transfused blood among African Americans due to higher rates of sickl... more Despite a specific need for transfused blood among African Americans due to higher rates of sickle cell disease, African Americans donate blood significantly less frequently than their White counterparts. This study describes the development and validation of culturally adapted measures of the transtheoretical model (TTM) constructs of Stage of Change, Decisional Balance, and Self-efficacy applied to blood donation in an African American sample. Exploratory and confirmatory analyses produced one pros and two cons scales for the Decisional Balance Inventory, and one scale for the Situational Selfefficacy Measure. Expected patterns for the Decisional Balance and Self-efficacy Scales by Stage of Change were found, but only the pros and one cons scale varied significantly. Results provide support for use of the TTM applied to blood donation and have important implications for development of effective assessment and intervention tools to increase blood donation among the African American population.
a b s t r a c t a r t i c l e i n f o Effective interventions require an understanding of the beh... more a b s t r a c t a r t i c l e i n f o Effective interventions require an understanding of the behaviors and cognitions that facilitate positive change as well as the development of psychometrically sound measures. This paper reports on the psychometric properties of the Temptations to Try Alcohol Scale (TTAS), including factorial invariance across different subgroups. Data were collected from 3565 6th grade RI middle school students. Structural equation modeling was used to determine the appropriate factorial invariance model for the 9-item TTAS. The measure consists of three correlated subscales: Social Pressure, Social Anxiety, and Opportunity. Three levels of invariance, ranging from the least to the most restrictive, were examined: Configural Invariance, which constrains only the factor structure and zero loadings; Pattern Identity Invariance, which requires factor loadings to be equal across the groups; and Strong Factorial Invariance, which requires factor loadings and error variances to be constrained. Separate analyses evaluated the invariance across two levels of gender (males vs. females), race (white vs. black) ethnicity (Hispanic vs. Non-Hispanic) and school size (small, meaning b 200 6th graders, or large). The highest level of invariance, Strong Factorial Invariance, provided a good fit to the model for gender (CFI: .95), race (CFI: .94), ethnicity (CFI: .94), and school size (CFI: .97). Coefficient Alpha was .90 for Social Pressure, .81 for Social Anxiety, and .82 for Opportunity. These results provide strong empirical support for the psychometric structure and construct validity of the TTAS in middle school students.
Little is known about the extent to which interrupted time series analysis (ITSA) can be applied ... more Little is known about the extent to which interrupted time series analysis (ITSA) can be applied to short, single-case study designs and whether those applications produce results consistent with visual analysis (VA). This article examines the extent to which ITSA can be applied to single-case study designs and compares the results based on two methods: ITSA and VA, using papers published in the Journal of Applied Behavior Analysis in 2010. The study was made possible by the development of software called UnGraph®, which facilitates the recovery of raw data from the graphs. ITSA was successfully applied to 94% of the examined graphs with the number of observations ranging from 8 to 136. Moderate to high lag-1 autocorrelations (>.50) were found for 46% of the data series. Effect sizes similar to group-level Cohen's d were identified based on the tertile distribution. Effects ranging from 0.00 to 0.99 were classified as small, those ranging from 1.00 to 2.49 as medium, and large effect sizes were defined as 2.50 or greater. Comparison of the conclusions from VA and ITSA had a low level of agreement (Kappa =.14, accounting for the agreement expected by chance). The results demonstrate that ITSA can be broadly implemented in applied behavior analysis research. These two methods should be viewed as complementary and used concurrently.
Currently little is known about the specific effects of tobacco policies on low income girls and ... more Currently little is known about the specific effects of tobacco policies on low income girls and women. Research is vital on such effects both in developed and developing countries.
Page 1. Multivariate Behavioral Research, 26 (2), 247-254 Copyright O 1991, Lawrence Erlbaum Asso... more Page 1. Multivariate Behavioral Research, 26 (2), 247-254 Copyright O 1991, Lawrence Erlbaum Associates, Inc. Cross-Sectional Time Series Designs: A General Transformation Approach Wayne F. Velicer University of Rhode Island ...
Http Dx Doi Org 10 1080 13548506 2012 748206, Jun 20, 2013
Predictive and external validity was studied among cluster profiles for sun protection behavior w... more Predictive and external validity was studied among cluster profiles for sun protection behavior within stages from Transtheoretical Model of behavior change using follow-up data. Data from participants in a home-based expert system were analyzed. Longitudinal patterns of clusters on the precontemplation, contemplation, and preparation stages of change were assessed. Differences between clusters on membership in action/maintenance stages and scores on the Sun Protection Behavior Scale (SPBS) were measured at 12 and 24 months after intervention. Differences between clusters on stage progression and on scores from the SPBS were found at 12 and 24 months after intervention at all stages. Predictive and external validity of sun protection subtypes was established using sun protection variables after a stage-matched intervention. Results provide information to improve interventions for sun protection.
Focus on Autism and Other Developmental Disabilities, 2005
Characteristics of persons with autism and other developmental disabilities may make this populat... more Characteristics of persons with autism and other developmental disabilities may make this population especially vulnerable to the effects of stress. Prior research on stress and its measurement in this population is reviewed. Using a single-case multielement design, this study explores the feasibility of measuring cardiovascular responses to four stressors in 10 individuals (age 13 to 37 years) with autism and other developmental disabilities. Results suggest that assessing cardiovascular responses is a viable procedure for identifying individual differences in reactivity to specific environmental stressors. Implications of this research and future directions for assessment are discussed.
This study evaluated how well predictions from the transtheoretical model (TTM) generalized from ... more This study evaluated how well predictions from the transtheoretical model (TTM) generalized from smoking to diet. Longitudinal data were used from a randomized control trial on reducing dietary fat consumption in adults (n 51207) recruited from primary care practices. Predictive power was evaluated by making a priori predictions of the magnitude of change expected in the TTM constructs of temptation, pros and cons, and 10 processes of change when an individual transitions between the stages of change. Generalizability was evaluated by testing predictions based on smoking data. Three sets of predictions were made for each stage: Precontemplation (PC), Contemplation (C) and Preparation (PR) based on stage transition categories of no progress, progress and regression determined by stage at baseline versus stage at the 12-month follow-up. Univariate analysis of variance between stage transition groups was used to calculate the effect size [omega squared (x 2 )]. For diet predictions based on diet data, there was a high degree of confirmation: 92%, 95% and 92% for PC, C and PR, respectively. For diet predictions based on smoking data, 77%, 79% and 85% were confirmed, respectively, suggesting a moderate degree of generalizability. This study revised effect size estimates for future theory testing on the TTM applied to dietary fat.
The most common criteria recommended by philosophers of science for evaluating theories were orga... more The most common criteria recommended by philosophers of science for evaluating theories were organised within a hierarchy ranging from the least to the most risky tests for theories of health behavior change. The hierarchy progressed across: (1) Clarity; (2) Consistency; (3) Parsimony; (4) Testable; (5) Predictive Power; (6) Explanatory Power; (7) Productivity; (8) Generalisable; (9) Integration; (10) Utility; (11) Efficacy; and (12) Impact. The hierarchy was applied to the Transtheoretical Model (TTM) as an example of a health behavior change theory. The application was from the perspective of critics and advocates of TTM. Examples of basic and applied research challenging and supporting TTM across the hierarchy of criteria are presented. The goal is to provide a model for comparing alternative theories and to evaluate progress across the hierarchy within a particular theory. As theories meet criteria at each step in the hierarchy, the research and applications they generate can have increasing impacts on the science and practice of health behavior change.
Despite the hypothesized link between arousal and behavior in persons with autism, there is a lac... more Despite the hypothesized link between arousal and behavior in persons with autism, there is a lack of idiographic research that directly assesses arousal responses to novel stimuli or social situations in this population. The current study used heart rate as a measure of sympathetic activity to compare arousal responses to the presentation of potentially stressful situations in five persons with autism and five age-and sex-matched typically developing individuals. Findings revealed that the group with autism showed significant responses to stressors only 22% of the time compared to the typically developing group, which showed significant responses 60% of the time. Interpretation of these results and methodological considerations for future research on arousal in persons with autism are discussed.
Despite a specific need for transfused blood among African Americans due to higher rates of sickl... more Despite a specific need for transfused blood among African Americans due to higher rates of sickle cell disease, African Americans donate blood significantly less frequently than their White counterparts. This study describes the development and validation of culturally adapted measures of the transtheoretical model (TTM) constructs of Stage of Change, Decisional Balance, and Self-efficacy applied to blood donation in an African American sample. Exploratory and confirmatory analyses produced one pros and two cons scales for the Decisional Balance Inventory, and one scale for the Situational Selfefficacy Measure. Expected patterns for the Decisional Balance and Self-efficacy Scales by Stage of Change were found, but only the pros and one cons scale varied significantly. Results provide support for use of the TTM applied to blood donation and have important implications for development of effective assessment and intervention tools to increase blood donation among the African American population.
a b s t r a c t a r t i c l e i n f o Effective interventions require an understanding of the beh... more a b s t r a c t a r t i c l e i n f o Effective interventions require an understanding of the behaviors and cognitions that facilitate positive change as well as the development of psychometrically sound measures. This paper reports on the psychometric properties of the Temptations to Try Alcohol Scale (TTAS), including factorial invariance across different subgroups. Data were collected from 3565 6th grade RI middle school students. Structural equation modeling was used to determine the appropriate factorial invariance model for the 9-item TTAS. The measure consists of three correlated subscales: Social Pressure, Social Anxiety, and Opportunity. Three levels of invariance, ranging from the least to the most restrictive, were examined: Configural Invariance, which constrains only the factor structure and zero loadings; Pattern Identity Invariance, which requires factor loadings to be equal across the groups; and Strong Factorial Invariance, which requires factor loadings and error variances to be constrained. Separate analyses evaluated the invariance across two levels of gender (males vs. females), race (white vs. black) ethnicity (Hispanic vs. Non-Hispanic) and school size (small, meaning b 200 6th graders, or large). The highest level of invariance, Strong Factorial Invariance, provided a good fit to the model for gender (CFI: .95), race (CFI: .94), ethnicity (CFI: .94), and school size (CFI: .97). Coefficient Alpha was .90 for Social Pressure, .81 for Social Anxiety, and .82 for Opportunity. These results provide strong empirical support for the psychometric structure and construct validity of the TTAS in middle school students.
Little is known about the extent to which interrupted time series analysis (ITSA) can be applied ... more Little is known about the extent to which interrupted time series analysis (ITSA) can be applied to short, single-case study designs and whether those applications produce results consistent with visual analysis (VA). This article examines the extent to which ITSA can be applied to single-case study designs and compares the results based on two methods: ITSA and VA, using papers published in the Journal of Applied Behavior Analysis in 2010. The study was made possible by the development of software called UnGraph®, which facilitates the recovery of raw data from the graphs. ITSA was successfully applied to 94% of the examined graphs with the number of observations ranging from 8 to 136. Moderate to high lag-1 autocorrelations (>.50) were found for 46% of the data series. Effect sizes similar to group-level Cohen's d were identified based on the tertile distribution. Effects ranging from 0.00 to 0.99 were classified as small, those ranging from 1.00 to 2.49 as medium, and large effect sizes were defined as 2.50 or greater. Comparison of the conclusions from VA and ITSA had a low level of agreement (Kappa =.14, accounting for the agreement expected by chance). The results demonstrate that ITSA can be broadly implemented in applied behavior analysis research. These two methods should be viewed as complementary and used concurrently.
Currently little is known about the specific effects of tobacco policies on low income girls and ... more Currently little is known about the specific effects of tobacco policies on low income girls and women. Research is vital on such effects both in developed and developing countries.
Page 1. Multivariate Behavioral Research, 26 (2), 247-254 Copyright O 1991, Lawrence Erlbaum Asso... more Page 1. Multivariate Behavioral Research, 26 (2), 247-254 Copyright O 1991, Lawrence Erlbaum Associates, Inc. Cross-Sectional Time Series Designs: A General Transformation Approach Wayne F. Velicer University of Rhode Island ...
Http Dx Doi Org 10 1080 13548506 2012 748206, Jun 20, 2013
Predictive and external validity was studied among cluster profiles for sun protection behavior w... more Predictive and external validity was studied among cluster profiles for sun protection behavior within stages from Transtheoretical Model of behavior change using follow-up data. Data from participants in a home-based expert system were analyzed. Longitudinal patterns of clusters on the precontemplation, contemplation, and preparation stages of change were assessed. Differences between clusters on membership in action/maintenance stages and scores on the Sun Protection Behavior Scale (SPBS) were measured at 12 and 24 months after intervention. Differences between clusters on stage progression and on scores from the SPBS were found at 12 and 24 months after intervention at all stages. Predictive and external validity of sun protection subtypes was established using sun protection variables after a stage-matched intervention. Results provide information to improve interventions for sun protection.
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