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1.  Family planning to promote physical activity: a randomized controlled trial protocol 
BMC Public Health  2015;15:1011.
Physical activity is associated with the reduction of several chronic conditions in adults. Additionally, physical activity is extremely important for children for their development and cognitive functioning and also to create a physically active lifestyle that continues into adulthood. Despite the known benefits of physical activity, only one in five adults are achieving the public health recommendations of 150 minutes of moderate-to-vigorous physical activity per week and only 13 % of boys and 6 % of girls between the ages of 5 and 17 years are meeting the guidelines of 60 minutes per day. This study aims to evaluate whether a planning condition improves adherence to regular physical activity compared to an education-only control condition among families. Families are eligible if there is at least one child between the ages of 6 and 12 years who is not meeting the Canadian Physical Activity Guidelines.
A six-month longitudinal randomized controlled trial will be used to compare the two conditions. Materials will be delivered at baseline with ‘booster’ sessions at six weeks and three months. Participants will be assessed at baseline and at six months with a fitness test, as well as questionnaires and accelerometery at baseline, six weeks, three months and six months. A total of 137 families have been recruited thus far from Greater Victoria. This study is ongoing and recruitment will continue until December 2015 with the target goal of reaching 160 families.
This protocol describes the implementation of a randomized controlled trial that utilizes planning strategies to try and increase physical activity among families. Research findings could be useful in public health in providing effective strategies to families to help decrease sedentary lifestyles. Additionally, findings may help to inform future interventions aimed at increasing physical activity among families.
Trial registration
This trial was registered on June 5, 2012 with the Clinical Trials Registry maintained by the National Library of Medicine at the National Institutes of Health. The registration ID is NCT01882192.
PMCID: PMC4594902  PMID: 26437939
Action Control; Children; Parents; Exercise; Intention-behavior gap
2.  GrOup based physical Activity for oLder adults (GOAL) randomized controlled trial: study protocol 
BMC Public Health  2015;15:592.
Physical activity has health benefits across the lifespan, yet only 13 % of Canadian older adults are sufficiently active. Results from a number of observational studies indicate that adults display positive preferences for exercising with others of a similar age and same gender, and that intra-group age- and gender-similarity are associated with elevated exercise adherence. However, research has yet to experimentally examine the extent to which intra-group age- and gender-related similarity affect exercise adherence behaviors.
The GrOup-based physical Activity for oLder adults (GOAL) trial is a three-arm randomized control trial that will examine the efficacy of two different group-based exercise programs for older adults (informed by the tenets of self-categorization theory) in relation to a standard group-based exercise program. Within this manuscript we outline the design and proposed evaluation of the GOAL trial. The first arm is comprised of exercise groups made up of participants of a similar-age and of the same gender; the second arm consists of groups with similar-aged mixed gender participants; the control arm is comprised of mixed-aged mixed gender participants. We aim to compare the adherence rates of participants across conditions, as well as potential moderation effects and mediating mechanisms.
Results from this trial will inform intervention designs to improve the exercise adherence behaviors of older adult. At a systems-level, should support be derived for the efficacy of the interventions tested in this trial, changing group composition (i.e., age, gender) represents a feasible program adaptation for physical activity centers.
Trial registration # NCT02023632. Registered December 13, 2013.
PMCID: PMC4483226  PMID: 26116237
Physical activity; Older adults; Adherence; Self-categorization theory; Group-dynamics
3.  Factors Associated with Higher Sitting Time in General, Chronic Disease, and Psychologically-Distressed, Adult Populations: Findings from the 45 & Up Study 
PLoS ONE  2015;10(6):e0127689.
This study examined factors associated with higher sitting time in general, chronic disease, and psychologically-distressed, adult populations (aged ≥45 years). A series of logistic regression models examined potential socio-demographic and health factors associated with higher sitting (≥6hrs/day) in adults from the 45 and Up Study (n = 227,187), including four separate subsamples for analysis comprising those who had ever had heart disease (n = 26,599), cancer (n = 36,381), diabetes (n = 19,550) or psychological distress (n = 48,334). Odds of higher sitting were significantly (p<.01) associated with a number of factors across these groups, with an effect size of ORs≥1.5 observed for the high-income ≥$70,000AUD, employed full-time and severe physical limitations demographics. Identification of key factors associated with higher sitting time in this population-based sample will assist development of broad-based, public health and targeted strategies to reduce sitting-time. In particular, those categorized as being high-income earners, full-time workers, as well as those with severe physical limitations need to be of priority, as higher sitting appears to be substantial across these groups.
PMCID: PMC4454645  PMID: 26039739
4.  Capitalizing on the Teachable Moment: Osteoarthritis Physical Activity and Exercise Net for Improving Physical Activity in Early Knee Osteoarthritis 
JMIR Research Protocols  2013;2(1):e17.
Practice guidelines emphasize the use of exercise and weight reduction as the first line of management for knee osteoarthritis (OA). However, less than half of the people with mild OA participate in moderate intensity physical activity. Given that physical activities have been shown to reduce pain, improve quality of life, and have the potential to reduce the progression of joint damage, many people with OA are missing the benefits of this inexpensive intervention.
The objectives of this study are (1) to develop a behavioral theory-informed Internet intervention called Osteoarthritis Physical Activity & Exercise Net (OPEN) for people with previously undiagnosed knee OA, and (2) to assess the efficacy of the OPEN website for improving physical activity participation through a proof-of-concept study.
OPEN was developed based on the theory of planned behavior. Efficacy of this online intervention is being assessed by an ongoing proof-of-concept, single-blind randomized controlled trial in British Columbia, Canada. We are currently recruiting participants and plan to recruit a total of 252 sedentary people with previously undiagnosed knee OA using a set of validated criteria. Half of the participants will be randomized to use OPEN and receive an OA education pamphlet. The other half only will receive the pamphlet. Participants will complete an online questionnaire at baseline, 3 months, and 6 months about their participation in physical activities, health-related quality of life, and motivational outcomes. In addition, we will perform an aerobic fitness test in a sub-sample of participants (n=20 per study arm). In the primary analysis, we will use logistic regression to compare the proportion of participants reporting being physically active at or above the recommended level in the 2 groups, adjusting for baseline measurement, age, and sex.
This study evaluates a theory-informed behavioral intervention at a time when people affected with OA tend to be more motivated to adopt an active lifestyle (ie, at the early stage of OA). Our approach, which consisted of the identification of early knee OA followed immediately by an online intervention that directly targets physical inactivity, can be easily implemented across communities.
Our online intervention directly targets physical inactivity at a time when the joint damage tends to be mild. If OPEN is found to be effective in changing long-term physical activity behaviors, it opens further opportunities to promote early diagnosis and to implement lifestyle interventions.
Trial Registration NCT01608282; (Archived by WebCite at
PMCID: PMC3650932  PMID: 23659903
osteoarthritis physical activity; Internet; lifestyle intervention; theory of planned behavior
5.  Parental correlates in child and adolescent physical activity: a meta-analysis 
Physical activity (PA) has a profound impact on health and development in children. Parental behaviors (i.e., modeling and support) represent an obvious important factor in child PA. The purpose of this paper was to provide a comprehensive meta-analysis that overcomes the limitations of prior narrative reviews and quantitative reviews with small samples.
Ten major databases were used in the literature search. One-hundred and fifteen studies passed the eligibility criteria. Both fixed and random effects models with correction for sampling and measurement error were examined in the analysis. Moderator analyses investigating the effects of child’s developmental age, study design, parental gender, measurement of child PA, and quality rating were performed.
Based on the random effects model, the results showed that parental modeling was weakly associated with child PA (summary r = .16, 95% CI .09-.24) and none of the proposed moderators were significant. Separate analyses examining the moderating effects of parental gender and boys’ PA found that that father-son PA modeling (r = .29, 95% CI .21-.36) was significantly higher compared to mother-son PA (r = .19, 95% CI .14-.23; p < .05). However, parental gender did not moderate the relationship between parental modeling and girls’ PA (p > .05). The random effects model indicated an overall moderate effect size for the parental support and child PA relationship (summary r = .38, 95% CI .30-.46). Here, the only significant moderating variable was the measurement of child PA (objective: r = .20, 95% CI .13-.26; reported: r = .46, 95% CI .37-.55; p < .01).
Parental support and modeling relate to child PA, yet our results revealed a significant degree of heterogeneity among the studies that could not be explained well by our proposed moderators.
PMCID: PMC4363182  PMID: 25890040
Preschool; Childhood; Adolescence; Physical activity; Parental support; Parental role modeling; Parental behaviours; Meta-analysis; Review
6.  Models accounting for intention-behavior discordance in the physical activity domain: a user’s guide, content overview, and review of current evidence 
There is a growing concern among researchers with the limited effectiveness and yet subsequent stagnation of theories applied to physical activity (PA). One of the most highlighted areas of concern is the established gap between intention and PA, yet the considerable use of models that assume intention is the proximal antecedent of PA. The objective of this review was to: 1) provide a guide and thematic analysis of the available models that include constructs that address intention-behavior discordance and 2) highlight the evidence for these structures in the PA domain. A literature search was conducted among 13 major databases to locate relevant models and PA studies published before August 2014. Sixteen models were identified and nine overall themes for post-intentional constructs were created. Of the 16 models, eight were applied to 36 PA studies. Early evidence supported maintenance self-efficacy, behavioral regulation strategies, affective judgments, perceived control/opportunity, habit, and extraversion as reliable predictors of post-intention PA. Several intention-behavior discordance models exist within the literature, but are not used frequently. Further efforts are needed to test these models, preferably with experimental designs.
Electronic supplementary material
The online version of this article (doi:10.1186/s12966-015-0168-6) contains supplementary material, which is available to authorized users.
PMCID: PMC4328062  PMID: 25890238
Theory; Intention-behavior gap; Volition; Post-intention; Exercise; Action control
7.  Associations between socioeconomic, parental and home environment factors and fruit and vegetable consumption of children in grades five and six in British Columbia, Canada 
BMC Public Health  2014;14:150.
Regular fruit and vegetable (FV) consumption has been associated with reduced chronic disease risk. Evidence from adults shows a social gradient in FV consumption. Evidence from pre-adolescent children varies and there is little Canadian data. This study assessed the FV intake of school children in British Columbia (BC), Canada to determine whether socio-economic status (SES), parental and the home environment factors were related to FV consumption.
As part of the BC School Fruit and Vegetable Nutrition Program, 773 British Columbia fifth-and sixth-grade school children (Mean age 11.3 years; range 10.3-12.5) and their parents were surveyed to determine FV consumption and overall dietary intake. Students completed a web-based 24-hour dietary food recall, and a student measure of socio-economic status (The Family Affluence Scale). Parents completed a self-administered survey about their education, income, home environment and perceptions of their neighbourhood and children’s eating habits. Correlations and multiple regression analyses were used to examine the association between SES, parental and home environment factors and FV consumption.
Approximately 85.8% of children in this study failed to meet minimum Canadian guidelines for FV intake (6 servings). Parent income and education were not significantly associated with child FV consumption but were associated with each other, child-reported family affluence, neighbourhood environment, access to FV, and eating at the table or in front of the television. Significant positive associations were found between FV consumption and child-reported family affluence, meal-time habits, neighbourhood environment and parent perceptions of the healthiness of their child’s diet; however, these correlations were weak (ranging from .089-.115). Multiple regression analysis showed that only child-reported family affluence significantly predicted FV consumption (std-β = 0.096 95% CI = 0.01 to 0.27).
The majority of children in our study were not meeting guidelines for FV intake irrespective of SES, parent perceptions or home environment, making this a population wide concern. An almost trivial socio-economic gradient was observed for the child-reported SES measure only. These results are consistent with several other studies of children. Longitudinal research is needed to further explore individual and social factors associated with FV consumption in childhood and their development over time.
PMCID: PMC3929144  PMID: 24517088
Child health; Socio-economic status; Fruit and vegetable consumption; Canada
8.  Oh baby! Motivation for healthy eating during parenthood transitions: a longitudinal examination with a theory of planned behavior perspective 
Transitioning to parenthood is a major life event that may impact parents’ personal lifestyles, yet there is an absence of theory-based research examining the impact of parenthood on motives for dietary behaviour. As a result, we are unaware of the social cognitive variables that predict eating behaviour among those transitioning to parenthood. The purpose of the study was to examine eating behaviour motives across 12 months within the framework of the theory of planned behavior (TPB) and compare these across groups of new parents, non-parents, and established parents.
Non-parents (n = 92), new parents (n = 135), and established parents (n = 71) completed TPB questionnaires assessing attitudes, subjective norms, perceived behavioral control (PBC), and intentions and three day food records at baseline, and 6- and 12-months post-delivery (for parents) and 6- and 12-months post-baseline (for non-parents).
Repeated measures ANOVAs revealed that among men, new- and established-parents had greater intentions to eat healthy compared to non-parents, F(2) = 3.59, p = .03. Among women, established parents had greater intentions than new- and non-parents, F(2) = 5.33, p = .01. Among both men and women during the first 6-months post-delivery, new-parents experienced decreased PBC, whereas established parents experienced increased PBC. Overall, affective attitudes were the strongest predictor of intentions for men (β = 0.55, p < .001) and women (β = 0.38, p < .01). PBC predicted changes in fruit and vegetable consumption for men (β = 0.45, p = .02), and changes in fat consumption for men (β = −0.25, p = .03) and women (β = −.24, p < .05), regardless of parent status.
The transition to parenthood for new and established parents may impact motivation for healthy eating, especially PBC within the framework of TPB. However, regardless of parental status, affective attitudes and PBC are critical antecedents of intentions and eating behaviour. Interventions should target affective attitudes and PBC to motivate healthy eating and may need to be intensified during parenthood.
PMCID: PMC3706269  PMID: 23829582
Theory of planned behaviour; Nutrition; Dietary behaviour; Parenthood
9.  Evaluating the uptake of Canada’s new physical activity and sedentary behavior guidelines on service organizations’ websites 
New evidence-based physical activity and sedentary behavior guidelines for Canadians were launched in 2011. As a consequence, service organizations that promote physical activity directly to the public needed to change their promotion materials to reflect the new guidelines. Little is known about the rate at which service organizations adopt and integrate new evidence-based guidelines and determinants of guideline adoption. In this natural observational study, we evaluated the rate of online adoption of the new guidelines among key service organizations that promote physical activity and examined participation in a booster webinar as a supplemental dissemination strategy. One hundred fifty nine service organization websites were coded by one of six raters prior to the release of the new guidelines as well as at 3, 6, and 9 months after the release. Online adoption of the guidelines increased during the coding period with 51 % of organizations posting the guidelines or related information on their websites. Organizations’ engagement in a webinar was associated with their adoption of the guidelines. The release of new Canadian Physical Activity and Sedentary Behaviour Guidelines led to increased guideline adoption on service organizations’ websites. However, adoption was not universal. In order for the uptake of the new guidelines to be successful, further efforts need to be taken to ensure that service organizations present physical activity guidelines on their websites. Comprehensive, active dissemination strategies tailored to address organizational barriers are needed to ensure online guideline adoption.
PMCID: PMC3717973  PMID: 24073168
Dissemination; Physical activity guidelines; Diffusion of innovations; Service organizations; Sedentary Behavior Guidelines
10.  Evidence-informed recommendations for constructing and disseminating messages supplementing the new Canadian Physical Activity Guidelines 
BMC Public Health  2013;13:419.
Few validated guidelines exist for developing messages in health promotion practice. In clinical practice, the Appraisal of Guidelines, Research, and Evaluation II (AGREE II) Instrument is the international gold standard for guideline assessment, development, and reporting. In a case study format, this paper describes the application of the AGREE II principles to guide the development of health promotion guidelines for constructing messages to supplement the new Canadian Physical Activity Guidelines (CPAG) released in 2011.
The AGREE II items were modified to suit the objectives of developing messages that (1) clarify key components of the new CPAG and (2) motivate Canadians to meet the CPAG. The adapted AGREE II Instrument was used as a systematic guide for the recommendation development process. Over a two-day meeting, five workgroups (one for each CPAG – child, youth, adult, older adult – and one overarching group) of five to six experts (including behavior change, messaging, and exercise physiology researchers, key stakeholders, and end users) reviewed and discussed evidence for creating and targeting messages to supplement the new CPAG. Recommendations were summarized and reviewed by workgroup experts. The recommendations were pilot tested among end users and then finalized by the workgroup.
The AGREE II was a useful tool in guiding the development of evidence-based specific recommendations for constructing and disseminating messages that supplement and increase awareness of the new CPAG (child, youth, adults, and older adults). The process also led to the development of sample messages and provision of a rationale alongside the recommendations.
To our knowledge, these are the first set of evidence-informed recommendations for constructing and disseminating messages supplementing physical activity guidelines. This project also represents the first application of international standards for guideline development (i.e., AGREE II) to the creation of practical recommendations specifically aimed to inform health promotion and public health practice. The messaging recommendations have the potential to increase the public health impact of evidence-based guidelines.
PMCID: PMC3654879  PMID: 23634998
Physical activity guidelines; AGREE II; Messaging; Knowledge translation
11.  Correlates of physical activity in a population-based sample of kidney cancer survivors: an application of the theory of planned behavior 
Over half of kidney cancer survivors (KCS) are completely inactive and only a quarter are meeting physical activity (PA) guidelines. This highlights the need to identify and understand the determinants of PA in this understudied population. The purpose of this study is to determine the social cognitive correlates of PA intention and behavior in KCS using the Theory of Planned Behavior (TPB).
All 1,985 KCS diagnosed between 1996 and 2010 in Alberta, Canada were mailed a self-report survey that consisted of the Godin Leisure Time Exercise Questionnaire and standard TPB items for intention, planning, perceived behavioral control (PBC), affective and instrumental attitudes, and descriptive and injunctive norms. Standard demographic and medical variables were also collected.
Completed surveys were received from 703 of 1,654 (43%) eligible KCS. The TPB was tested using structural equation modelling and demonstrated an adequate-to-good fit to the data [χ² = 256.88, p < .001; TLI = 0.97; CFI = 0.98; RMSEA = 0.06, 90% CI = 0.05-0.06].
There were significant pathways to PA from PBC (ß = 0.18, p = 0.02), planning (ß = 0.22, p < 0.01), and intention (ß = 0.31, p < 0.01); and to planning from intention (ß = 0.81, p < 0.01). In addition, there were significant model pathways to intention from instrumental attitude (ß = 0.28, p = 0.03), descriptive norm (ß = 0.09, p = 0.01), and PBC (ß = 0.52, p < 0.01). Overall, the TPB accounted for 69%, 63%, and 42% of the variance in intention, planning and PA, respectively.
The TPB appears to be a useful model for explaining PA in KCS. All TPB constructs except injunctive norm and affective attitude were useful for explaining intention with PBC emerging as the largest correlate. Developing PA interventions based on the TPB may be effective in promoting PA in KCS and may lead to important improvements in health.
PMCID: PMC3489870  PMID: 22866956
Exercise; Motivation; Social cognitive models; Correlates
12.  Does action planning moderate the intention-habit interaction in the exercise domain? A three-way interaction analysis investigation 
Journal of Behavioral Medicine  2011;35(5):509-519.
Both habit strength and action planning have been found to moderate the intention-exercise behaviour relationship, but no research exists that has investigated how habit strength and action planning simultaneously influence this relationship. The present study was designed to explore this issue in a prospective sample of undergraduate students (N = 415): action planning, habit strength, intention, attitudes, subjective norms and perceived behavioural control were assessed at baseline and exercise behaviour was assessed 2 weeks later. Both habit strength and action planning moderated the intention-exercise relationship, with stronger relationship at higher levels of planning or habit strength. Decomposing a significant action planning × habit strength × intention interaction showed that the strength of the intention-exercise relationship progressed linearly through levels of action planning and habit strength. These novel results show that action planning strengthens the intention-habit strength interaction in the exercise domain: exercise interventions should therefore focus on simultaneously bolstering action planning and habit strength.
PMCID: PMC3439603  PMID: 21979328
Exercise behaviour; Intention-exercise relationship; Habit strength; Action planning; Interaction
13.  Mediators of physical activity behaviour change among adult non-clinical populations: a review update 
An understanding of the determinants of physical activity through mediators of behaviour change is important in order to evaluate the efficacy of interventions. Prior reviews on this topic noted that few studies employed mediator analyses in experimental physical activity trials; the purpose of this review is to update these prior reviews in order to evaluate the state of our present understanding of interventions that include proposed mediators of behaviour change.
Literature was identified through electronic database (e.g., MEDLINE, psychINFO) searching. Studies were eligible if they described a published experimental or quasi-experimental trial examining the effect of an intervention on physical activity behaviour and mediator change in non-clinical adult populations. Quality of included studies was assessed and the analyses examined the symmetry between mediators and behaviour change.
Twenty seven unique trials passed the eligibility criteria and 22 were included in the analysis with scores of moderate or higher quality. Half of the studies reviewed failed to show an intervention effect on PA. The remaining studies showed evidence that the intervention affected changes in the proposed mediators, but tests of mediated effect were performed in only six of these 11 cases and demonstrated mixed outcomes. Differences by theory were not discernable at this time, but self-regulation constructs had the most evidence for mediation.
Published literature employing mediators of change analyses in experimental designs is still relatively elusive since the time of prior reviews; however, the general null findings of changes in mediating constructs from these interventions are a more timely concern. Changes in self-regulation constructs may have the most effect on changes in PA while self-efficacy and outcome expectation type constructs have negligible but limited findings. Innovation and increased fidelity of interventions is needed and should be a priority for future research.
PMCID: PMC2876989  PMID: 20459781
14.  A test of cognitive mediation in a 12-month physical activity workplace intervention: does it explain behaviour change in women? 
Attempts to demonstrate the efficacy of interventions aimed at increasing physical activity (PA) have been mixed. Further, studies are seldom designed in a manner that facilitates the understanding of how or why a treatment is effective or ineffective and PA intervention designs should be guided by a heavier reliance upon behavioral theory. The use of a mediating variable framework offers a systematic methodological approach to testing the role of theory, and could also identify the effectiveness of specific intervention components. The primary purpose of this paper was to test the mediating role that cognitive constructs may have played in regards to the positive effect that a workplace behavioral intervention had on leisure-time PA for women. A subsidiary purpose was to examine the cross-sectional relationships of these cognitive constructs with PA behavior.
The Physical Activity Workplace Study was a randomized controlled trial which compared the effects of stage-matched and standard print materials upon self-reported leisure-time PA, within a workplace sample at 6 and 12-months. In this secondary analysis we examined the mediation effects of 14 psychosocial constructs across 3 major social-cognitive theories which were operationalized for the intervention materials and measured at baseline, 6 and 12-months. We examined change in PA and change in the psychological constructs employing a mediation strategy proposed by Baron and Kenny for: (1) the first 6-months (i.e., initial change), (2) the second 6-months (i.e., delayed change), and (3) the entire 12-months (overall change) of the study on 323 women (n = 213 control/standard materials group; n = 110 stage-matched materials group).
Of the 14 constructs and 42 tests (including initial, delayed and overall change) two positive results were identified (i.e., overall change in pros, initial change in experiential powerful intervention approaches processes), with very small effect sizes. However, these mediating results were eliminated after adjusting for the multiple statistical tests.
The intervention did not change these mediators in any substantive way, and show a similar pattern to prior research where interventions generally do not result in a change in mediation of behavior change. It is important to report mediation results in randomized controlled trials whether the findings are null or positive. Future studies may wish to focus on more detailed dose-response issues between mediators and behavior, the inclusion of moderators that could affect individual change, or different mediator constructs at higher levels of measurement specificity. Continued work on innovative and more powerful PA intervention approaches are needed.
PMCID: PMC2874508  PMID: 20438632
15.  Prediction of leisure-time walking: an integration of social cognitive, perceived environmental, and personality factors 
Walking is the primary focus of population-based physical activity initiatives but a theoretical understanding of this behaviour is still elusive. The purpose of this study was to integrate personality, the perceived environment, and planning into a theory of planned behaviour (TPB) framework to predict leisure-time walking.
Participants were a random sample (N = 358) of Canadian adults who completed measures of the TPB, planning, perceived neighbourhood environment, and personality at Time 1 and self-reported walking behaviour two months later.
Analyses using structural equation modelling provided evidence that leisure-time walking is largely predicted by intention (standardized effect = .42) with an additional independent contribution from proximity to neighbourhood retail shops (standardized effect = .18). Intention, in turn, was predicted by attitudes toward walking and perceived behavioural control. Effects of perceived neighbourhood aesthetics and walking infrastructure on walking were mediated through attitudes and intention. Moderated regression analysis showed that the intention-walking relationship was moderated by conscientiousness and proximity to neighbourhood recreation facilities but not planning.
Overall, walking behaviour is theoretically complex but may best be addressed at a population level by facilitating strong intentions in a receptive environment even though individual differences may persist.
PMCID: PMC2174941  PMID: 17974022

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