Evaluating Theories of Health Behavior Change: A Hierarchy of Criteria Applied to the Transtheoretical Model

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.     

Examining memory for heterosexual college students' sexual experiences using an electronic mail diary.

To examine memory for sexual expenences, the authors asked 37 sexually active, nonmonogamous, heterosexual college students to complete an e-mail diary every day for 1 month. The diary contained questions about their sexual behaviors. Six to 12 months later, they returned for a surprise memory test, which contained questions about their sexual experiences from the diary phase. They were asked about their sexual partners, the types of sexual experiences they had, and condom use. Participants underreported the number of partners they had, but they overreported both sexual experiences and condom use. The results have implications for both sexual health educators and for people who engage in high-risk sexual behaviors.     

Coping in Caregivers of Youth with Spinal Cord Injury

This study examined coping among caregivers of youth with spinal cord injuries (SCI). Using a cross-sectional survey study design, 164 caregivers completed a demographics questionnaire and the Brief COPE. Their children, youth with SCI ages 7–18, completed the Kidcope. T-tests were conducted to examine differences in caregiver coping by demographic and injury-related factors. Further, logistic regression models were evaluated to examine predictive relationships between caregiver coping and youth coping. Several demographic and injury-related factors were related to caregiver coping, including caregiver gender, race, and education, as well as youth gender, age at injury, and time since injury. In the logistic regressions, two caregiver coping strategies were related to youth coping: caregiver self-blame coping was related to youth self-criticism, and caregiver behavioral disengagement coping (giving up attempts to cope) was related to youth blaming others coping. The findings suggest that caregiver coping may play a role in the coping of their children, and should be considered when addressing coping among youth with SCI.     

Reduced phonological similarity effects in patients with damage to the cerebellum

Ten cerebellar patients were compared to 10 control subjects on a verbal working memory task in which the phonological similarity of the words to be remembered and their modality of presentation were manipulated. Cerebellar patients demonstrated a reduction of the phonological similarity effect relative to controls. Further, this reduction did not depend systematically upon the presentation modality. These results first document that qualitative differences in verbal working memory may be observed following cerebellar damage, indicating altered cognitive processing, even though behavioral output as measured by the digit span may be within normal limits. However, the results also present problems for the hypothesis that the cerebellar role is specifically associated with articulatory rehearsal as conceptualized in the Baddeley-Hitch model of working memory.     

Premature mortality due to suicide, homicide, and motor vehicle accidents in health service delivery areas: comparison of status Indians in British Columbia, Canada, with all other residents

From each of 15 health regions, potential years of life lost (PYLL) before age 75 for Status Indians is compared for select causes of death with all other residents. Mortality data from 1991 to 2001 for rates of PYLL (standardized to the 1991 population) are from tables of the British Columbia Vital Statistics Agency and First Nations and Inuit Health Branch in 2002. PYLL rate differences and rate ratios were compared for two groups with significance of the former indicated by the 95% confidence interval. Overall, the rates of PYLL for suicide, homicide, and deaths due to motor vehicle accidents were about 224%, 340%, and 248% higher among Status Indians than all other residents. Rates of PYLL for homicide and deaths from motor vehicle accidents among Status Indian women exceeded those of other residents who were men. For suicide, Status Indian men ranked first and all other male residents of British Columbia ranked second.     

The effects of bilingualism on toddlers' executive functioning

Bilingual children have been shown to outperform monolingual children on tasks measuring executive functioning skills. This advantage is usually attributed to bilinguals’ extensive practice in exercising selective attention and cognitive flexibility during language use because both languages are active when one of them is being used. We examined whether this advantage is observed in 24-month-olds who have had much less experience in language production. A battery of executive functioning tasks and the cognitive scale of the Bayley test were administered to 63 monolingual and bilingual children. Native bilingual children performed significantly better than monolingual children on the Stroop task, with no difference between groups on the other tasks, confirming the specificity of bilingual effects to conflict tasks reported in older children. These results demonstrate that bilingual advantages in executive control emerge at an age not previously shown.     

Predictors of African American and European American adolescents' endorsement of race-conscious social policies

To examine the predictors of adolescents' evaluations of affirmative action and school desegregation policies, African American and European American students (ns = 94 and 116, respectively; aged 14 to 17 years) attending a racially diverse high school in the Midwestern United States completed measures of (a) implicit racial attitudes, (b) knowledge about historical racism, and (c) perceptions of and attributions for racial disparities. The following day, adolescents learned about either a proposed affirmative action policy (n = 101) or a school desegregation policy (n = 109) and completed measures of their attitudes toward the policy. Results indicated racial differences in policy support and in the factors predicting policy support. Theoretical implications of the findings are discussed.     

Interpersonal Goals and Susceptibility to Peer Influence: Risk Factors for Intentions to Initiate Substance Use during Early Adolescence

Though peer socialization theories are prominent in the adolescent substance use literature, variability in the degree to which adolescents are vulnerable to peer influence is likely, and few studies have examined this issue. This study examines the association between perceived peer substance use/approval of substance use and adolescent intentions to initiate alcohol and cigarette use, and how social goals moderate this relationship. Results support the moderating role of social goals, and suggest important differences across alcohol and cigarette use. Peer use and approval of cigarette use was associated with future intentions to smoke for adolescents with strong agentic goals, and peer use and approval of alcohol use was associated with intentions to drink for adolescents with strong communal goals. These findings suggest that adolescent substance use theories and prevention programs focusing on peer socialization should consider individual differences in social goals and potential differences in peer influence across drugs.     

Sample size in psychological research over the past 30 years

The American Psychological Association (APA) Task Force on Statistical Inference was formed in 1996 in response to a growing body of research demonstrating methodological issues that threatened the credibility of psychological research, and made recommendations to address them. One issue was the small, even dramatically inadequate, size of samples used in studies published by leading journals. The present study assessed the progress made since the Task Force's final report in 1999. Sample sizes reported in four leading APA journals in 1955, 1977, 1995, and 2006 were compared using nonparametric statistics, while data from the last two waves were fit to a hierarchical generalized linear growth model for more in-depth analysis. Overall, results indicate that the recommendations for increasing sample sizes have not been integrated in core psychological research, although results slightly vary by field. This and other implications are discussed in the context of current methodological critique and practice.