Leona S. Aiken's research while affiliated with Arizona State University and other places

Publications (88)

Article
Purpose: This study examined whether the Predictive Early Assessment of Reading and Language (PEARL), a dynamic assessment of narratives that measures language comprehension and production, accurately classifies Navajo preschoolers with typically developing (TD) language or with language impairment (LI). Method: Ninety 4- and 5-year-old Navajo p...
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In an upper-middle class setting, we explored associations between students’ peer reputation in Grades 6 and 7 with adjustment at Grade 12. With a sample of 209 students, a confirmatory factor analysis (CFA) of peer reputation dimensions supported a 4-factor model (i.e., popular, prosocial, aggressive, isolated). Structural equation models were use...
Article
In multiple regression researchers often follow up significant tests of the interaction between continuous predictors X and Z with tests of the simple slope of Y on X at different sample-estimated values of the moderator Z (e.g., ±1 SD from the mean of Z). We show analytically that when X and Z are randomly sampled from the population, the variance...
Article
Cognitive changes that occur during mid-life and beyond are linked to both aging and the menopause transition. Studies in women suggest that the age at menopause onset can impact cognitive status later in life; yet, little is known about memory changes that occur during the transitional period to the post-menopausal state. The 4-vinylcyclohexene di...
Article
The Undergraduate Study in Psychology (USP) is a collaborative effort of the American Psychological Association (APA) Board of Educational Affairs, the Education Directorate, and the Center for Workforce Studies to collect information on undergraduate psychology programs, faculty, students, and curriculum. The overall goal of USP is to paint a port...
Article
Background: Health behaviour models focus primarily on intrapersonal constructs (e.g., self-efficacy) which are good predictors of intention but less so of actual behaviour. Influences from the social environment, namely from close others, may improve prediction of engagement in ongoing behaviour. Objectives: This study sought to broadly assess...
Article
The undergraduate curriculum in psychology profoundly reflects and shapes the discipline. Yet, reliable information on the undergraduate psychology curriculum has been difficult to acquire due to insufficient research carried out on unrepresentative program samples with disparate methods. In 2014, APA launched the first systematic effort in a decad...
Article
Previous studies have documented small differences between the bachelor of arts (BA) and the bachelor of science (BS) psychology degrees in their general education core requirements, particularly mathematics and science courses. But are there differences between the BA and BS degrees within the psychology curriculum? Using data from the Undergradua...
Article
Background The infertility associated with primary ovarian insufficiency (POI) presents significant emotional challenges requiring psychosocial adjustment. Few investigations have explored the longitudinal process of adaptation to POI. Purpose This longitudinal investigation tests a model of adjustment to POI that includes separate psychosocial vul...
Article
We address two challenges in data analysis of group research. First, data may be clustered (i.e., responses of individual group members are correlated). Second, some dependent variables may consist of integer counts of number of occurrences of an event. Familiar ANOVA and regression models provide nonoptimal analyses in both cases. Standard multile...
Article
Background: Fatigue is a debilitating symptom of fibromyalgia (FM) that has limited treatment options. Some evidence, however, has linked positive social engagement with reduced within-day fatigue. Purpose: This study elaborated longitudinal within-day and across-day relations between FM fatigue and social enjoyment. Methods: One hundred seven...
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We constructed an 11-arm, walk-through, human radial-arm maze (HRAM) as a translational instrument to compare existing methodology in the areas of rodent and human learning and memory research. The HRAM, utilized here, serves as an intermediary test between the classic rat radial-arm maze (RAM) and standard human neuropsychological and cognitive te...
Article
With increasing age and multimorbidity, medication regimens become demanding, potentially resulting in suboptimal adherence. Social support has been discussed as a predictor of adherence, but previous findings are inconsistent. The study examines general social support, medication-specific social support, and social conflict as predictors of adhere...
Conference Paper
How many days per week do you exercise for 30 minutes or more? Never? Once or twice? Every other day? Most days? Every day? Coarsely grouped counts such as this are commonly used in the behavioral sciences. When these variables are used as outcome variables, they often violate the assumptions of both linear regression and models designed for catego...
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Objective: Despite long-standing social psychological research supporting the influence of injunctive norms (i.e., what is commonly approved or disapproved) on behavior, support for this influence on health behaviors is limited. We examined the utility of correcting misperceptions of injunctive norms for improving sun protection and whether change...
Article
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This study compares the analysis of covariance (ANCOVA), difference score, and residual change score methods in testing the group effect for pretest–posttest data in terms of statistical power and Type I error rates using a Monte Carlo simulation. Previous research has mathematically shown the effect of stability of individual scores from pretest t...
Article
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The present research tested whether the effect of stereotype threat on calculus performance was moderated by calculus GPA and math identification in advanced undergraduate women majoring in science, technology, and engineering (STEM) fields. Women (n = 102) were randomly assigned to one of three conditions—stereotype threat, gender equivalence, or...
Article
A Monte Carlo simulation was conducted to investigate the robustness of four latent variable interaction modeling approaches (Constrained Product Indicator [CPI], Generalized Appended Product Indicator [GAPI], Unconstrained Product Indicator [UPI], and Latent Moderated Structural Equations [LMS]) under high degrees of non-normality of the observed...
Article
Intervention research aimed at modifying health behavior can go beyond merely assessing behavioral outcomes to characterizing the putative mechanisms by which interventions bring about behavior change. To characterize these mechanisms, a two-stage research program is required. The first stage involves the development and evaluation of a psychosocia...
Article
Neighborhood social cohesion (NSC) may contribute to understanding how neighborhood contexts influence the physical and mental health of residents. We examined the relation of NSC to self-rated mental and physical health and evaluated the mediating role of NSC on relations between neighborhood socioeconomic status, ethnic composition, and health. A...
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Interaction and quadratic effects in latent variable models have to date only rarely been tested in practice. Traditional product indicator approaches need to create product indicators (e.g., x 1 2, x 1 x 4) to serve as indicators of each nonlinear latent construct. These approaches require the use of complex nonlinear constraints and additional mo...
Article
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The purpose of this research was to select from the health belief model (HBM), theories of reasoned action (TRA) and planned behaviour (TPB), information-motivation-behavioural skills model (IMB) and social cognitive theory (SCT) the strongest longitudinal predictors of women's condom use and to combine these constructs into a single integrated mod...
Chapter
Despite the long history of research on social norms in psychology, sociology, and other disciplines, social norms remain relatively underutilized as a mechanism for changing health behaviors. However, normative influence is a powerful motivator of behavior that can and should be brought to bear in health promotion research. Accordingly, research t...
Article
The purpose of this research was to propose and evaluate a psychosocial model of young women's intentions to obtain breast implants and the preparatory steps taken towards having breast implant surgery. The model integrated anticipated regret, descriptive norms and image norms from the media into the theory of planned behaviour (TPB). Focus groups...
Chapter
Linear regression characterizes the relationship of a set of independent variables or predictors X1, X2, …Xp to a single dependent variable or criterion Y. The goals of linear regression are (1) to characterize the overall strength of the relationship of the set of predictors to the criterion and (2) to identify those individual predictors or subse...
Article
To provide an explanation of perceived susceptibility judgment that accounts for both inconsistencies among commonly used measures of perceived susceptibility (i.e., absolute risk, direct comparative risk, and indirect comparative risk) and their inconsistent relationships to disease risk factors. Inconsistencies are attributed to differential proc...
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Objective: This study examines age-differential association patterns between intentions, planning and physical activity in young and middle-aged individuals. The effectiveness of planning to bridge the intention-behaviour gap is assumed to increase with advancing age. We explore the use of behaviour change strategies that include selection, optimi...
Article
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To explain, through mediation analyses, the mechanisms by which ATHENA (Athletes Targeting Healthy Exercise and Nutrition Alternatives), a primary prevention and health promotion intervention designed to deter unhealthy body shaping behaviors among female high school athletes, produced immediate changes in intentions for unhealthy weight loss and s...
Article
Count data reflect the number of occurrences of a behavior in a fixed period of time (e.g., number of aggressive acts by children during a playground period). In cases in which the outcome variable is a count with a low arithmetic mean (typically < 10), standard ordinary least squares regression may produce biased results. We provide an introductio...
Article
Replies to the comment Ramifications of increased training in quantitative methodology by Herbet Zimiles on the current authors original article "Doctoral training in statistics, measurement, and methodology in psychology: Replication and extension of Aiken, West, Sechrest, and Reno's (1990) survey of PhD programs in North America". The current aut...
Article
In a survey of all PhD programs in psychology in the United States and Canada, the authors documented the quantitative methodology curriculum (statistics, measurement, and research design) to examine the extent to which innovations in quantitative methodology have diffused into the training of PhDs in psychology. In all, 201 psychology PhD programs...
Article
To examine the putative determinants of two osteoporosis-preventive behaviors, calcium consumption and weight-bearing exercise, in 2 samples of young women (Sample 1, n = 202; Sample 2, n = 209). A common psychosocial model of both behaviors, comprising the health belief model and augmented with constructs drawn from social cognitive theory and the...
Article
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The purpose of the study was to examine the zero-order and unique relations of effortful attentional and behavioral regulation, reactive impulsivity, and anger/frustration to Chinese first and second graders' internalizing and externalizing symptoms, as well as the prediction of adjustment from the interaction of anger/frustration and effortful con...
Article
To assess women's perceptions of risk for osteoporosis and to identify factors that shape those perceptions. A community sample of 358 women (aged 40-86) rated their perceived risk of osteoporosis and provided detailed information about factors underlying their risk perceptions. Their open-ended responses were content analysed. On average, particip...
Article
This longitudinal study examined factors underlying hormone therapy (HT) use before and after termination of the landmark Women's Health Initiative (WHI) estrogen plus progestin HT trial in July 2002, after which dramatic reductions in HT use occurred. A community sample of 324 women (aged 40-86) from Arizona was interviewed four times between 1995...
Article
We tested a psychosocial model of condom-use intentions among incarcerated adolescents, who are at exceptionally high risk for sexually transmitted diseases, including HIV. Incarcerated adolescents (n = 150: 139 male, 11 female; age = 13 to 17 years; 44% Hispanic, 39% Caucasian) provided face-to-face interviews. The model included past condom use a...
Article
To evaluate the psychometric properties of the Profile of Chronic Pain: Screen (PCP:S) in primary care. The PCP:S is a brief assessment device designed to gauge pain severity, interference, and emotional burden. Questionnaire survey with short-term reliability and validity follow-up. Two hundred and forty-four outpatients (52% female) with chronic...
Article
Variables that have been coarsely categorized into a small number of ordered categories are often modeled as outcome variables in psychological research. The authors employ a Monte Carlo study to investigate the effects of this coarse categorization of dependent variables on power to detect true effects using three classes of regression models: ord...
Article
To document outcomes of a randomized trial of the PhoenixCare demonstration program of palliative care and coordinated care/case management for seriously chronically ill individuals who simultaneously received active treatment from managed care organizations (MCOs). Patients, continuously enrolled between July 1999, and March 2001, were randomly as...
Article
An appearance-based sun-protection intervention program was developed, implemented, and evaluated in a sample of 211 Caucasian women (ages 18-25) randomly assigned to the sun-protection program or to a stress management (control) program. The sun-protection program incorporated a novel construct of image norms of aspirational peers (i.e., female me...
Article
The aim of the present research was the development and validation of a set of instruments, collectively called the Profile of Chronic Pain: Extended Assessment Battery (PCP:EA), designed to be administered to adults (between the ages of 25 to 80) after establishing the existence of a chronic pain problem. The final 86-item version of the PCP:EA co...
Chapter
Interaction effects refer to the effects of particular unique combinations of variables on an outcome that would not be expected from their average effects. When two variables interact, the conditional effect of one variable at a particular value of the other variable depends on the specific value of the other variable. One variable moderates the e...
Article
From a biopsychosocial perspective, assessing chronic pain's psychological impact should involve at minimum the measurement of pain severity, functional interference, and pain-related emotional burden. This article details the development of a brief instrument, the 15-item Profile of Chronic Pain: Screen (PCP:S), designed to address these three key...
Article
The relationships of epidemiological (objective) risk indices, perceived disease characteristics, and cognitive heuristics to women's perceived susceptibility to breast cancer, heart disease, and osteoporosis in a community sample of 312 women ages 40-86 were examined. Epidemiological indices accounted for a small to moderate proportion of the vari...
Article
Personality correlates of older women's perceived susceptibility to breast cancer, heart disease, and osteoporosis were examined in a community sample of 312 women aged 40-86. A latent factor of general perceived susceptibility to disease was shown to underlie disease-specific perceptions of susceptibility. Affect-related personality traits (neurot...
Article
This research examines the predictors of 2-year declines in physical and mental health for beneficiaries surveyed in the Medicare Health Outcomes Survey (HOS). Regression results indicate that age, arthritis of the hip/knee, sciatica, and pulmonary diseases, comorbidity at baseline, and increased comorbidity between baseline and followup were predi...
Article
In response to a perceived need for patient access to palliative care and supportive services prior to hospice eligibility, Phoenix-based Hospice of the Valley (HOV) applied for and received a 3-year demonstration grant (1999-2001) from The Robert Wood Johnson (RWJ) Promoting Excellence in End-Of-Life Care Project. HOV established the PhoenixCare p...
Chapter
This chapter provides a comprehensive introduction to multiple regression analysis (MR), a highly flexible system for examining the relationship of a collection of independent variables (predictors) to a single dependent variable (criterion). The independent variables may be quantitative (e.g., personality traits, family income) or categorical (e.g...
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A growing body of research implicates internalized homophobia--the internalization of society's antihomosexual sentiments by gay and lesbian people--as a factor contributing to HIV-related sexual risk behavior in gay and bisexual men. Although accumulating evidence links internalized homophobia and sexual risk behavior, no study has explored the im...
Article
A model of condom-use intentions and behavior that we previously developed for women was replicated and extended with heterosexual men (n= 203; M age = 20.1 years). The general determinants of intentions to use condoms were consistent for men and women. The predictors of general condom attitudes and condom-use self-efficacy differed across gender....
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The authors used structural equation modeling to examine expressed emotion (EE) in relatives of outpatients with panic disorder with agoraphobia (n = 42) or obsessive-compulsive disorder (n = 60). EE was examined as a function of patients' illness and personality and as a function of characteristics of relatives themselves. EE was operationalized i...
Article
A psychosocial model of sun protection and sunbathing as distinct behaviors was developed on 202 young Caucasian women and replicated in an independent sample (n = 207). Proximal outcomes were intention to sun protect and intention to sunbathe; distal outcomes included sun protection and sunbathing behavior measured 5 months later. Objective risk f...
Article
The current investigation examined whether the positive association of family conflict to adolescent depression and conduct problems is attenuated by maternal, paternal, and peer attachment, and maternal and paternal monitoring, within a low-income, multiethnic sample of 284 adolescents. Parental attachment and monitoring moderated the link from fa...
Article
The current investigation examined whether the positive association of family conflict to adolescent depression and conduct problems is attenuated by maternal, paternal, and peer attachment, and maternal and paternal monitoring, within a low‐income, multiethnic sample of 284 adolescents. Parental attachment and monitoring moderated the link from fa...
Article
Many areas of the behavioral sciences have few measures that are accepted as the standard for the operationalization of a construct. One consequence is that there is hardly ever an articulated and understood framework for the units of the measures that are employed. Without meaningful measurement units, theoretical formulations are limited to state...
Article
The authors investigated the impact of the introduction of a condom into an initial sexual encounter on the perception of the male condom proposer and the likely outcome of the sexual encounter. College students viewed a videotape depicting the development of an initial sexual encounter. Method of condom introduction (verbal: nonverbal, no condom c...
Article
Confirmatory factor analysis was used to explore a 3-factor model of expressed emotion (Criticism, Emotional Overinvolvement, and Positivity) in a sample of 104 outpatients with agoraphobia or obsessive-compulsive disorder and 104 relatives of these patients. Multiple methods of measurement included the Camberwell Family Interview, observation of v...
Article
The authors assessed the impact of three designs (randomized experiment, nonequivalent control group design, regression discontinuity design) on estimates of effect size of a university-level freshman remedial writing program. Designs were implemented within the same context, same time frame, and with the same population. The 375 freshman participa...
Article
The controversy concerning the efficacy of mammography screening for reducing breast cancer mortality among women aged 40 to 49 has continued throughout much of this decade. We examined the impact of this controversy on a community sample of women aged 40 to 60 in 2 data collections (n = 146 and n = 51, respectively), each time following a critical...
Article
A comprehensive model of the determinants of condom use among young women was developed, tested, and replicated, with longitudinal follow-up to assess predictive utility of the model for condom use over time. Participants in Study 1 and Study 2 were 198 female undergraduates (mean age, 18.6 years) and 238 female undergraduates (mean age, 19.1 years...
Article
Notes that preventive interventions are often composed of multiple components. The authors focus on design and statistical modeling methods for understanding the unique effects of each component in such multicomponent interventions. They consider the assumptions, strengths and weaknesses of several research designs that permit researchers to partia...
Article
A multicomponent intervention to increase condom use in sexually active young women was designed, implemented, and evaluated in a randomized experiment. Participants were 198 unmarried female college students (mean age = 18.6 years) who received a 1-session condom promotion intervention or a control (stress management) intervention. The condom prom...
Article
Theories hypothesizing interactions between a categorical and one or more continuous variables are common in personality research. Traditionally, such hypotheses have been tested using nonoptimal adaptations of analysis of variance (ANOVA). This article describes an alternative multiple regression-based approach that has greater power and protects...
Article
The debate concerning the effectiveness of mammography screening for reducing breast cancer mortality rates among women in their 40s is explored. The most recent data from randomized clinical trials (RCTs) are presented. Lack of adequate statistical power in these trials is addressed. Temporal factors in young women's breast cancer (sojourn and sur...
Article
Interrelations among perceived risk for breast cancer, objective risk factors, and both breast self-examination (BSE) and mammography screening were examined across two waves of a longitudinal study of breast cancer screening. Participants were a community sample of 335 predominantly White middle-class women, aged 37 to 77, who had not had breast c...
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Multilevel models are becoming increasingly used in applied educational social and economic research for the analysis of hierarchically nested data. In these random coefficient regression models the parameters are allowed to differ over the groups in which the observations are nested. For computational ease in deriving parameter estimates, predicto...
Article
Two theory-based programs to increase mammography screening rates among asymptomatic women were implemented and evaluated in the community. One program (E) was based on the Health Belief Model (HBM); the second program (EP) added exercises adapted from the social psychology of compliance. Program impact on screening among 295 primarily Caucasian, m...
Article
The use of structural equation modeling (SEM) is illustrated for comparative treatment outcome research conducted with heterogeneous clinical subpopulations within large multimodality treatment settings. All analyses are accomplished with SEM analogs of more familiar classical multivariate techniques. The effect of the early period of treatment on...
Article
The utility of the health belief model (HBM) for predicting compliance with the American Cancer Society recommendations for mammography screening over and above demographics, knowledge, physician input, and objective risk for breast cancer was assessed. In all, 615 predominantly middle-class White women, age 35-92, were surveyed in 1987-1989. A mul...
Article
Assessing the contributions of individual components in multi-component interventions poses complex challenges for prevention researchers. We review the strengths and weaknesses of designs and analyses that may be useful in answering three questions: (1) Is each of the individual components contributing to the outcome? (2) Is the program optimal? a...
Article
The focus of the present study was the daily life activities and self-perceived health and life quality of heroin addicts both in and out of methadone treatment, based on 219 addicts followed for 8 months after treatment entry. The majority of outcome evaluations of methadone treatment have focused on the "hard" outcome criteria of drug use levels,...
Article
We tested the predictive utility of the health belief model (HBM) for adherence with a complex, ongoing medical regimen in the context of a chronically ill youthful population (56 adolescent outpatients with insulin-dependent diabetes mellitus; mean age = 14 years). A three-construct model of health beliefs was tested: Threat (perceived susceptibil...
Book
This study investigated 3 broad classes of individual-differences variables (job-search motives, competencies, and constraints) as predictors of job-search intensity among 292 unemployed job seekers. Also assessed was the relationship between job-search intensity and reemployment success in a longitudinal context. Results show significant relations...
Article
The validity of true experiments is threatened by a class of self-report biases that affect all respondents at pretest but which are diminished by treatment, yielding noncomparable treated and control subjects at posttest. These biases include inaccurate self-evaluations due to (a) lack of understanding of dimensions of self-rating, (b) unconscious...
Article
Full-text available
A survey of all PhD programs in psychology in the US and Canada assessed the extent to which advances in statistics, measurement, and methodology have been incorporated into doctoral training. In all, 84% of the 222 departments responded. The statistical and methodological curriculum has advanced little in 20 yrs; measurement has experienced a subs...
Article
Despite the effectiveness of mammography, a large percentage of eligible women do not obtain screening mammograms. Two programs designed to increase the use of mammography were designed, implemented and evaluated. One hundred and fifty-six women were recruited and assigned to an Educational plus Psychological program (EP), an Educational program (E...
Article
" A survey of all PhD programs,in psychology in the United States and Canada,assessed the extent to which advances in statistics, measurement, and method- ology have been incorporated,into doctoral training. In all, 84% of the 222 departments responded. The statistical and methodological,curriculum,has advanced,little in 20 years; measurement,has e...

Citations

... First, item scores for each factor were taken average to calculate the variable. Then, we mean-centered all in dependent and moderator variables to remove the non-essential correlations between the relevant independent variables and the corresponding multiplication terms (Cohen et al., 2014). The mean-centered variables then were multiplied to create the multiplication terms. ...
... Ini dapat terjadi apabila orang tua berperan dan berfungsi dalam pengasuhan, memberikan dukungan, kasih sayang, dan menanamkan nilai-nilai positif agar anak dapat tumbuh dan berkembang menjadi pribadi yang positif. Hubungan yang baik antara orang tua dan remaja adalah sumber daya penting yang memberikan ketahanan dan kekuatan, serta penyesuaian diri pada remaja (Formoso et al., 2000). Sebaliknya, konflik antara orang tua dan remaja dapat menjadi penyebab kenakalan remaja. ...
... Similarly, the Diné (North American Southwestern Tribal Nation) concept of Hó zhǫ is a way of being in the world that also emphasizes acquiring knowledge by looking and listening (Cajete, 2002;Werito, 2014), often in the context of storytelling (Denetdale, 2014;Henderson et al., 2018). Citizen Potawatomi Nation biologist Robin Wall Kimmerer describes Anishinaabe (North American Great Lakes First Nations) traditions of observation in similar ways, writing ''Or have we become dismissive of what takes no technology but only time and patience to perceive? ...
... Prosocial behavior is characterized as being voluntary oriented toward supporting others' well-being and includes actions such as helping, sharing, and cooperation (Batson & Powell, 2003;Eisenberg & Miller, 1987;Padilla-Walker & Carlo, 2014). Indeed, prior research has suggested a positive association between prosocial behavior and achievement (e.g., Caprara et al., 2000;Curlee et al., 2019;Wentzel, 1993). ...
... The formula calculating the SE of the simple slope is used in Rogosa (1980Rogosa ( , 1981. It is adopted in the Aiken and West (1991) test (Liu et al., 2017). Liu et al. (2017) point out that it is possible to use alternative CIs for simple slopes calculated by bootstrap techniques and Bayesian techniques. ...
... Conversely, menopause is the symbol of perpetual cessation of menstrual cycles. After menopause, circulating hormone levels are altered and various changes occur in the reproductive organs, such as ovarian aging, vulvovaginal atrophy, and breast atrophy [21][22][23][24][25]. ...
... In 2000, the American Psychological Association Board of Educational Affairs delegated a Task Force on Psychology Majors Competencies (Hailstorks, Norcross, Pfund, Aiken, Stamm, & Christidis, 2016). This task force was appointed to create a set of learning goals and defined learning outcomes for undergraduate psychology majors. ...
... Older adults seem to participate in greater physical activity when family and friends provide emotional, appraisal, and companionship support. For example, married older adult women with husbands who demonstrate care and concern for their desire to be active and compliment them on their mastery of a skill accumulate more hours of physical activity per week (Ranby & Aiken, 2016). Additionally, older adults with family and friends who encourage them to be physically active and accompany them are more likely to engage in greater moderate-tovigorous physical activity (Bohm et al., 2016;Carlson et al., 2012). ...
... The introductory psychology (IP) course is typically a student's first exposure to the field of psychology. The IP course is offered at nearly all degree-granting institutions of higher learning in the United States (Norcross et al., 2016). In total, 1.2-1.8 million students enroll in the course annually in the United States (Gurung et al., 2016), making it the second most popular course in the nation, after English Composition (Adelman, 2004). ...
... To obtain the final model, stepwise backward selection modelling was used, where the co-variate with the highest p-value was eliminated from the model, before repeating the modelling process. Furthermore, to confirm the final model, we performed a forward selection process, whereby pvalues were obtained through likelihood ratio tests of the full model with the selected co-variate against the model without the co-variate, to provide consistent estimates for regression parameters (West et al., 2007). Classification trees (CT), based on conditional inference (party package, Hothorn et al., 2023) were also constructed for each survey period (2008-2012; 2013-2017; and 2018-2020). ...