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James O Prochaska

Publications and source records attributed to James O Prochaska.

35 records · Page 2Linked to original sources
PubMed2005

Identifying high- and low-success smoking cessation subgroups using signal detection analysis.

Signal detection analysis was used to identify mutually exclusive groups of smokers (n = 602) at high and low likelihood for smoking cessation 6- and 18-months post-entry into a smoking cessation intervention. Overall quit rates were 10% at 6-months and 18% at 18-months. Four subgroups were identified at 6-months and five at 18-months. The highest quit-rate subgroup at both time points (42% and 52% cessation, respectively) had low perceived stress. The lowest quit-rate subgroup (7% and 13% cessation, respectively) had higher perceived stress, lower self-efficacy to not smoke, lower use of behavioral processes at 6-months, and higher use of pros of smoking at 18-months. These smoker profiles may be useful in developing targeted smoking cessation interventions. Addressing perceived stress in smoking cessation interventions may help to improve smoking cessation success rates.

Adolescent↗
PubMed2005

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

OBJECTIVE: Tailored interventions based on stage of change and other Transtheoretical Model constructs have been effective for promoting smoking cessation. Recent cluster analyses based on the Pros and Cons from the Decisional Balance and the Situational Temptations measures performed within the stages have suggested the existence of distinct cluster subtypes. Cluster subtypes would permit the development of tailored interventions focusing on these subtypes. This study attempts to replicate cluster subtypes within the Contemplation stage of change in a secondary analysis of data from a sample of current smokers (N=3967). METHOD: Four random samples of 400 were selected from the 1734 Contemplators. 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 Contemplators, Progressing, Early Contemplators, and Disengaged) were found and replicated across samples. The clusters were externally validated using the 10 Processes of change and 2 smoking behavior variables (cigarettes per day and time before first morning cigarette). Statistically significant (p<0.05) multivariate effects were found for the 10 Processes of change in all four samples. The cluster groups differed on 7 or more of the processes in each sample. Significant multivariate effects were also found for the smoking behavior variables in all samples (p<0.001). CONCLUSIONS: The cluster patterns closely replicate earlier findings and provide evidence for the existence of clusters subtypes within the Contemplation stage of change.

Adolescent↗
PubMed2005

Stage-based expert systems to guide a population of primary care patients to quit smoking, eat healthier, prevent skin cancer, and receive regular mammograms.

BACKGROUND: Treating multiple health behavior risks on a population basis is one of the most promising approaches to enhancing health and reducing health care costs. Previous research demonstrated the efficacy of expert system interventions for three behaviors in a population of parents. The interventions provide individualized feedback that guides participants through the stages of change for each of their risk behaviors. This study extended that research to a more representative population of patients from primary care practice and to targeting of four rather than three behaviors. METHODS: Stage-based expert systems were applied to reduce smoking, improve diet, decrease sun exposure, and prevent relapse from regular mammography. A randomized clinical controlled trial recruited 69.2% of primary care patients (N = 5407) at home via telephone. Three intervention contacts were delivered for each risk factor at 0, 6, and 12 months. The primary outcome measures were the percentages of at-risk patients at baseline who progressed to the action or maintenance stages at 24-month follow-up for each of the risk behaviors. RESULTS: Significant treatment effects were found for each of the four behaviors, with 25.4% of intervention patients in action or maintenance for smoking, 28.8% for diet, and 23.4% for sun exposure. The treatment group had less relapse from regular mammography than the control group (6% vs. 10%). CONCLUSION: Proactive, home-based, and stage-matched expert systems can produce relatively high population impacts on multiple behavior risks for cancer and other chronic diseases.

Adult↗
PubMed2005

Comparing participants and nonparticipants recruited for an effectiveness study of nicotine replacement therapy.

BACKGROUND: Interventions for smoking cessation have been typically evaluated on reactively recruited samples in clinical trials (efficacy trials). However, to have an impact on smoking rates in a general population, the intervention should also be evaluated with proactively recruited representative samples (effectiveness trials). PURPOSE: The characteristics of participants and two groups of nonparticipants recruited for a population-based nicotine replacement therapy study were compared. METHODS: All members of a large New England Veterans' Administration Medical Center were contacted, and interviews were completed with 3,239 identified smokers (at least 10 cigarettes per day). At the end of the interview, all smokers were offered participation in a multiple intervention study. Of the interviewed smokers, 2,915 verbally agreed to participate in the study (90%). Of those who gave initial verbal consent, 2,054 returned the written informed consent form and became participants (70%). RESULTS: The participants (full consent group) differed significantly from both nonparticipant groups-that is, the smokers who were interviewed but declined participation by active refusal (survey only group) and those who gave verbal consent but passively refused participation by failing to return the written consent form (verbal consent only group). Participants were more likely to be married, younger, and female; to live with others; and to have previously used or considered using nicotine replacement therapy. The survey only group was also more likely to be in the precontemplation stage (54%), whereas the participants were more likely to be in the contemplation (46%) or preparation stage (35%). The verbal consent only group was intermediate of the other two groups in stage-of-change characteristics. CONCLUSIONS: An important finding was that it is possible to recruit a large proportion of a sample of identified smokers to an nicotine replacement therapy study. However, the participants are likely to differ in significant ways from those who either actively or passively decline participation.

Female↗
PubMed2004

Factorial invariance and internal consistency for the decisional balance inventory--short form.

A crucial assumption for a measure is that it is factorially invariant; that is, the measurement model is the same in different subgroups and across different occasions. The invariance of the short form of the decisional balance inventory was investigated using data from a representative sample of smokers (N=4144). Separate analyses evaluated the invariance across two levels of gender (male and female), four levels of education (grade school, high school, college, and graduate school), two levels of race (white and black), four levels of age (18-25, 26-35, 36-50, and 50+), and across four assessment occasions. The results indicated that the decisional balance inventory demonstrated strong factorial invariance across the four demographic variables and across assessments.

Adolescent↗
PubMed2004

A comparison of four self-report smoking cessation outcome measures.

Interventions for smoking cessation have been developed by researchers in a number of distinct disciplines. As a result, a variety of different outcome measures have been developed and employed. This paper will report an analysis that compares four smoking cessation outcome measures on data gathered from three population-based studies: (1) 24-hour point prevalence abstinence, (2) 7-day point prevalence abstinence, (3) 30-day prolonged abstinence, and (4) 6-month prolonged abstinence. The three studies provided a total of 41 mean estimates for the first three measures but only 28 mean estimates for the 6-month prolonged abstinence measure. The data demonstrate an extremely high relationship between all four measures. The first three measures (24-hour point prevalence, 7-day point prevalence, and 30-day prolonged abstinence) all correlated in excess of.98 with each other. The only measure that did not demonstrate the same degree of almost perfect equivalence was 6-month prolonged abstinence, but even here the lowest correlation with the other three measures was.82. For practical purposes, the first three measures will result in the same conclusions when used as outcome measures in smoking cessation studies.

Data Collection↗
PubMed2004

Size, consistency, and stability of stage effects for smoking cessation.

In the transtheoretical model (TTM), the stage effect is one of the most important determinants of health behavior change. Randomly assigned to 1 of 11 treatment conditions were 4653 smokers. A total of 66 stage effects were possible with 6 for each of the 11 treatment groups. The results suggest that brief stage-matched interventions that help populations progress one stage could produce 75% more abstinence. Interventions that help populations progress two stages could produce 300% more abstinence. The results also support the importance of replicating the stage effects across treatment conditions and over time.

Adult↗
PubMed2004

Multiple risk expert systems interventions: impact of simultaneous stage-matched expert system interventions for smoking, high-fat diet, and sun exposure in a population of parents.

Three stage-based expert system interventions for smoking, high-fat diet, and unsafe sun exposure were evaluated in a sample of 2,460 parents of teenagers. Eighty-four percent of the eligible parents were enrolled in a 2-arm randomized control trial, with the treatment group receiving individualized feedback reports for each of their relevant behaviors at 0, 6, and 12 months as well as a multiple behavior manual. At 24 months, the expert system outperformed the comparison condition across all 3 risk behaviors, resulting in 22% of the participants in action or maintenance for smoking (vs. 16% for the comparison condition), 34% for diet (vs. 26%), and 30% for sun exposure (vs. 22%). Proactive, home-based, and stage-matched expert systems can produce significant multiple behavior changes in at-risk populations where the majority of participants are not prepared to change.

Adolescent↗
PubMed2004

Assessing stage of change and informed decision making for Internet participation in health promotion and disease management.

The Internet is a potentially powerful source of low- or no-cost programs through which individuals can be guided in changing their behavior to improve health. Using the Transtheoretical Model and survey methodology, the authors sought to produce reliable and valid instruments for assessing "stage of change" and "informed decision making," and to generate cross-sectional and longitudinal stage-of-change data for a sample of Internet users, as they apply to Internet use for health promotion and disease management. They found that only 24.7% of their sample used the Internet for these purposes and concluded that considerably more research will be needed to determine how to help significant percentages of populations to progress toward enhancing their health through the Internet.

Adolescent↗
PubMed2003

Changes in diabetes self-care behaviors make a difference in glycemic control: the Diabetes Stages of Change (DiSC) study.

OBJECTIVE: This study compared diabetes Treatment As Usual (TAU) with Pathways To Change (PTC), an intervention developed from the Transtheoretical Model of Change (TTM), to determine whether the PTC intervention would result in greater readiness to change, greater increases in self-care, and improved diabetes control. RESEARCH DESIGN AND METHODS: Participants were stratified by diabetes treatment and randomized to treatment with PTC or TAU as well as being randomized regarding receipt of free blood testing strips. The PTC consisted of stage-matched personalized assessment reports, self-help manuals, newsletters, and individual phone counseling designed to improve readiness for self-monitoring of blood glucose (SMBG), healthy eating, and/or smoking cessation. A total of 1029 individuals with type 1 and type 2 diabetes who were in one of three pre-action stages for either SMBG, healthy eating, or smoking were recruited. RESULTS: For the SMBG intervention, 43.4% of those receiving PTC plus strips moved to an action stage, as well as 30.5% of those receiving PTC alone, 27.0% of those receiving TAU plus strips, and 18.4% of those receiving TAU alone (P < 0.001). For the healthy eating intervention, more participants who received PTC than TAU (32.5 vs. 25.8%) moved to action or maintenance (P < 0.001). For the smoking intervention, more participants receiving PTC (24.3%) than TAU (13.4%) moved to an action stage (P < 0.03). In intention-to-treat (ITT) analysis of those receiving the SMBG intervention, PTC resulted in a greater reduction of HbA(1c) than TAU, but this did not reach statistical significance. However, in those who moved to an action stage for the SMBG and healthy eating interventions, HbA(1c) was significantly reduced (P < 0 0.001). Individuals who received the healthy eating intervention decreased their percentage of calories from fat to a greater extent (35.2 vs. 36.1%, P = 0.004), increased servings of fruit per day (1.89 vs. 1.68, P = 0.016), and increased vegetable servings (2.24 vs. 2.06, P = 0.011) but did not decrease weight. However, weight loss for individuals who received the healthy eating intervention and who increased SMBG frequency as recommended was significantly greater, with a 0.26-kg loss in those who remained in a pre-action SMBG stage but a 1.78-kg loss in those performed SMBG as recommended (P <or= 0. 01). CONCLUSIONS: This study demonstrates that this intervention has the potential of positively impacting the health of broad populations of individuals with diabetes, not just the minority who are ready for change.

Blood Glucose↗
PubMed2003

Stages of change for healthy eating in diabetes: relation to demographic, eating-related, health care utilization, and psychosocial factors.

OBJECTIVES: To identify diabetes-related characteristics of individuals at different stages of readiness to change to healthy, low-fat eating. RESEARCH DESIGN AND METHODS: Stage-based differences in demographic, eating-related, health care utilization, and psychosocial factors were examined in a sample of 768 overweight (BMI >27 kg/m(2)) individuals with diabetes enrolled in a randomized behavioral intervention trial. RESULTS: Stage-based differences occurred for type 1 diabetic participants on percent of calories from fat and number of daily vegetable servings. For type 2 diabetic participants, sex, disease-specific quality of life, percent calories from fat, and number of daily vegetables servings differed across stages. Those in action stages were more likely to be female and have a better quality of life and healthier eating habits. Type 2 diabetic insulin-requiring participants in action stages were more likely to be married. Social support was highest for those in the contemplation stage and lowest for those in the action stage. Type 2 diabetic participants on pills in the action stages were older, had a lower BMI, ate more fruit, were nonsmokers, recently attended diabetes education, had a better quality of life and social support, and had less stress. One anomalous finding for type 2 diabetic participants was that precontemplators scored similarly to those in action stages. CONCLUSIONS: These data validate the Transtheoretical Model, where those in the action stages displayed healthier eating. They also indicate that demographic and psychosocial factors may mediate readiness to change diet. Precontemplators were a heterogeneous group and may need individually tailored interventions.

Analysis of Variance↗
PubMed2000

Understanding the adoption of arthritis self-management: stages of change profiles among arthritis patients.

Clinical observations and recent studies suggest that arthritis patients vary considerably in their involvement in self-management efforts. In the literature on health promotion, there is growing recognition that patients may be at different stages of change with respect to the adoption of self-management strategies. The major goal of the present study was to examine whether cluster analysis could be used to identify homogeneous subgroups of patients having persistent arthritis pain based on their responses to a stages of change questionnaire. Participants in this study (103 patients having rheumatoid arthritis and 74 patients having osteoarthritis) completed a stages-of-change measure specific to adoption of a self-management approach to their arthritis. A cluster analysis identified five distinct subgroups of arthritis patients: (1) precontemplation - 44% of the sample; (2) contemplation - 11% of the sample; (3) preparation - 22% of the sample; (4) unprepared action - 6% of the sample; and (5) prepared maintenance - 17% of the sample. These subgroups are generally consistent with what might be expected based on the transtheoretical model of stages of change by Prochaska and DiClemente (Prochaska JO, DiClemente CC. Towards a comprehensive, transtheoretical model of change: states of change and addictive behaviors. In: Miller WR, Heather N, editors. Applied clinical psychology, 2nd ed. Treating addictive behaviors, New York: Plenum Press, 1998. pp. 3-24.), and may have important clinical implications. For example, it is possible that the arthritis subgroups identified may predict arthritis patients' participation in and responsiveness to pain-coping skills training, exercise interventions, or other formal self-management training programs. Also, one may be able enhance the outcomes of self-management interventions for arthritis by tailoring treatment to the patient's particular stage.

Adaptation, Psychological↗
PubMedDate not supplied

Application of the transtheoretical model to fruit and vegetable consumption among economically disadvantaged African-American adolescents: preliminary findings.

PURPOSE: To examine the application of the transtheoretical model (TTM) to fruit and vegetable consumption among economically disadvantaged African-American adolescents. METHODS: Scales for measuring decisional balance, situational self-efficacy, and processes of change for fruit and vegetable consumption were developed and pretested with 57 economically disadvantaged African-American adolescents. The scales and measures for assessing stages of change, demographic variables, and fruit and vegetable consumption were administered to a separate sample of 262 participants. t-tests for independent samples and analysis of variance were used to examine differences in TTM variables and fruit and vegetable consumption across stages of change. RESULTS: Two-factor solutions for decisional balance and processes of change and a three-factor solution for situational self-efficacy provided the best fit to the data. Alpha coefficients of reliability for the scales ranged from .77 (experiential change processes) to .91 (pros). Participants in action-maintenance stages evidenced higher pros, self-efficacy, and fruit and vegetable consumption and significantly lower cons than did participants in precontemplation and contemplation-preparation stages. Also, participants in action-maintenance stages used processes of change more frequently than did those in precontemplation-contemplation-preparation stages. The use of experiential and behavioral processes within these stages did not differ significantly, as posited. DISCUSSION: Observed differences in TTM variables and fruit and vegetable consumption by stage of change in this sample of economically disadvantaged African-American adolescents were consistent with theory and previous applications of the model to fruit and vegetable consumption in adults. With replication studies, the TTM may be appropriate for designing interventions to increase fruit and vegetable consumption among this population.

Adolescent↗