Vicki S. Conn

Interventions to Increase Physical Activity Among Healthy Adults: Meta-Analysis of Outcomes

OBJECTIVES We conducted a meta-analysis summarizing the effects of interventions designed to increase physical activity among healthy adults. METHODS Our comprehensive searches located 358 reports eligible for inclusion. We used random-effects analyses to synthesize data, and we used meta-analytic analogues of regression and analysis of variance to examine potential moderator variables. We also explored moderator variable robustness and publication bias. RESULTS We computed meta-analytic results from studies comprising 99 011 participants. The overall mean effect size for comparisons of treatment groups versus control groups was 0.19 (higher mean for treatment participants than for control participants). This effect size is consistent with a mean difference of 496 ambulatory steps per day between treatment and control participants. Exploratory moderator analyses suggested that the characteristics of the most effective interventions were behavioral interventions instead of cognitive interventions, face-to-face delivery versus mediated interventions (e.g., via telephone or mail), and targeting individuals instead of communities. Participant characteristics were unrelated to physical activity effect sizes. Substantial between-studies heterogeneity remained beyond individual moderators. CONCLUSIONS Interventions designed to increase physical activity were modestly effective. Interventions to increase activity should emphasize behavioral strategies over cognitive strategies.

A meta-analysis of exercise interventions among people treated for cancer

GoalThis review applied meta-analytic procedures to integrate primary research findings that tested exercise interventions among people treated for cancer.MethodsExtensive literature searching strategies located published and unpublished intervention studies that tested exercise interventions with at least five participants (k=30). Primary study results were coded. Meta-analytic procedures were conducted.Main resultsThe overall weighted mean effect size (ES) for two-group comparisons was 0.52 (higher mean for treatment than control) for physical function, 0.35 for symptoms other than fatigue, and 0.27 for body composition. More modest positive ESs were documented for mood (0.19), quality of life (0.14), fatigue (0.11), and exercise behavior (0.04). ESs were larger among single-group pre–post design studies. ESs among control group participants were typically negative and not (statistically) significantly different from 0.ConclusionsExercise interventions resulted in small positive effects on health and well-being outcomes among existing studies. Future research should examine intervention-specific characteristics that result in optimal results, such as dose.

Grey Literature in Meta-Analyses

BackgroundIn meta-analysis, researchers combine the results of individual studies to arrive at cumulative conclusions. Meta-analysts sometimes include “grey literature” in their evidential base, which includes unpublished studies and studies published outside widely available journals. Because grey literature is a source of data that might not employ peer review, critics have questioned the validity of its data and the results of meta-analyses that include it. ObjectiveTo examine evidence regarding whether grey literature should be included in meta-analyses and strategies to manage grey literature in quantitative synthesis. MethodsThis article reviews evidence on whether the results of studies published in peer-reviewed journals are representative of results from broader samplings of research on a topic as a rationale for inclusion of grey literature. Strategies to enhance access to grey literature are addressed. ResultsThe most consistent and robust difference between published and grey literature is that published research is more likely to contain results that are statistically significant. Effect size estimates of published research are about one-third larger than those of unpublished studies. Unfunded and small sample studies are less likely to be published. Yet, importantly, methodological rigor does not differ between published and grey literature. ConclusionsMeta-analyses that exclude grey literature likely (a) over-represent studies with statistically significant findings, (b) inflate effect size estimates, and (c) provide less precise effect size estimates than meta-analyses including grey literature. Meta-analyses should include grey literature to fully reflect the existing evidential base and should assess the impact of methodological variations through moderator analysis.

Interventions to increase physical activity among aging adults: a meta-analysis.

Objectives: This review applied meta-analytic procedures to integrate primary research findings that test interventions to increase activity among aging adults. Methods: We performed extensive literature searching strategies and located published and unpublished intervention studies that measured the activity behavior of at least five participants with a mean age of 60 years or greater. Primary study results were coded, and meta-analytic procedures were conducted. Results: The overall effect size, weighted by sample size, was dw = .26 ± .05. Effect sizes were larger when interventions targeted only activity behavior, excluded general health education, incorporated self-monitoring, used center-based exercise, recommended moderate intensity activity, were delivered in groups, used intense contact between interventionists and participants, and targeted patient populations. Effect sizes were larger for studies that measured exercise duration and studies with a time interval of less than 90 days between intervention and behavior measurement. Conclusions: These findings suggest that group-delivered interventions should encourage moderate activity, incorporate self-monitoring, target only activity, and encourage center-based activity. Findings also suggest that patient populations may be especially receptive to activity interventions. Primary research testing interventions in randomized trials to confirm causal relationships would be constructive.

Integrative Review of Physical Activity Intervention Research with Aging Adults

This paper reviews randomized, controlled trials (RCTs) that have attempted to increase physical activity behavior by aging adults. A systematic review was necessary because numerous studies target older adults, and previous reviews have addressed a limited range of primary studies. Computerized database, ancestry, and extensive search strategies by authors of research reported in English between 1960 and 2000 located diverse intervention trials. RCTs reporting endurance physical activity or exercise behavioral outcomes for at least five subjects were included. Integrative review methods were used to summarize extant research. Forty‐two studies were retrieved. Seventeen RCTs with 6,391 subjects were reviewed. A wide variety of intervention strategies were reported. The most common interventions were self‐monitoring, general health education, goal setting, supervised center‐based exercise, problem solving, feedback, reinforcement, and relapse prevention education. Few studies individually adapted motivational interventions, used mediated intervention delivery, or integrated multiple theoretical frameworks into the intervention. Links between individual intervention components and effectiveness were not clear. Common methodological weaknesses included small samples, untested outcome measures, and time‐limited longitudinal designs. Significant numbers of aging adults increased their physical activity in response to experimental interventions. The amount of increased activity rarely equaled accepted behavior standards to achieve positive health outcomes. Further work is essential to identify successful strategies to increase activity by larger numbers of elders and to accelerate the increase in activity by those who change activity behaviors. Sex and ethnic differences need further investigation. There is a vital need for rigorously designed studies to contribute to this science.

OLDER ADULTS AND EXERCISE : PATH ANALYSIS OF SELF-EFFICACY RELATED CONSTRUCTS

BACKGROUND Despite the potential benefits of exercise, rates of exercise among older adults remain low. Self-efficacy expectation is the strongest correlate of exercise behavior or exercise behavior change. OBJECTIVES To develop and test the predictive ability of a model of exercise among older adults. METHOD The models constructs related to exercise and self-efficacy included outcome expectancy, perceived barriers to exercise, perceived health, age, and lifelong leisure exercise among adults 65 to 100 years years of age (N=147). Data were collected by personal interview and analyzed with path analysis. RESULTS Self-efficacy expectation had a strong direct effect on exercise. Outcome expectancy contributed little to exercise in the model. Perceived barriers and self-efficacy expectation, followed by age, exerted the most total influence on exercise scores. CONCLUSIONS Lifelong leisure exercise exerts its influence on exercise through self-efficacy beliefs, further emphasizing the importance of efficacy. Also important are perceived barriers to exercise. Further research should examine self-efficacy expectations, perceived barriers, and age as predictors of exercise among older adults at different stages of health behavior change.

Depressive Symptom Outcomes of Physical Activity Interventions: Meta-analysis Findings

BackgroundPhysical activity (PA) is consistently linked to mental health outcomes.PurposeThis meta-analysis synthesized depressive symptom outcomes of supervised and unsupervised PA interventions among healthy adults.MethodsComprehensive searching and coding were applied to PA interventions among adults without clinical depression. Analyses included random-effects standardized means, Q, and moderator analysis using analysis of variance and regression meta-analytic analogues.ResultsTreatment versus control comparisons yielded a standardized mean effect size of 0.372 among 38 supervised PA studies and 0.522 among 22 unsupervised PA studies. Preliminary moderator analyses suggested that supervised PA interventions may be more effective when they include flexibility/resistance and low-intensity exercise. Unsupervised PA interventions may be more effective when they recommend center-based PA. Methodological moderators (random assignment, control group management) were identified.ConclusionsThese findings document that PA interventions reduce depressive symptoms even in adults without clinical depression. Moderator analyses suggest directions for future research as well as practice.

Interventions to Improve Medication Adherence Among Older Adults: Meta-Analysis of Adherence Outcomes Among Randomized Controlled Trials

PURPOSE This study investigated the effectiveness of interventions to improve medication adherence (MA) in older adults. DESIGN AND METHODS Meta-analysis was used to synthesize results of 33 published and unpublished randomized controlled trials. Random-effects models were used to estimate overall mean effect sizes (ESs) for MA, knowledge, health outcomes, and health services utilization. RESULTS Data were synthesized across 11,827 participants. Interventions significantly improved MA (ES = 0.33), knowledge (ES = 0.48), and diastolic blood pressure (ES = 0.19). Nonsignificant effects were found for systolic blood pressure (ES = 0.21), other health outcomes (ES = 0.04), and health services utilization (ES = 0.16). Moderator analyses showed larger adherence ESs for interventions employing special medication packaging, dose modification, participant monitoring of medication effects and side effects, succinct written instructions, and standardized (not tailored) interventions. Larger effects were found when a moderate proportion of participants were women, for participants taking 3-5 medications, and when pill count adherence was measured. IMPLICATIONS The findings document that interventions increase MA in older adults. The considerable heterogeneity in the magnitude of effects across studies and results of the moderator analyses demonstrate the need for additional empirical research to optimize interventions.

Meta-analysis of quality of life outcomes following diabetes self-management training

Purpose The purpose of this meta-analysis was to meet the need to quantify the influence of diabetes self-management training on quality of life (QOL) of adult diabetes patients. Methods Extensive literature searching located published and unpublished diabetes self-management intervention studies that measured QOL outcomes among at least 5 subjects with type 1 or 2 diabetes. Data were extracted from primary study reports which included interventions designed to improve diabetes self-management and adequate data to calculate effect sizes. Random-effects meta-analytic procedures were used to estimate overall effects between treatment and control groups at outcome assessment and between baseline and outcome data for both treatment subjects and control subjects. Results Exhaustive searching yielded 20 comparisons across 1892 subjects. The comparisons between treatment and control group outcomes following interventions yielded an effect size of 0.281. The comparisons between treatment group at baseline and outcome measurement yielded an effect size of 0.312 to 0.313. Each of these effect sizes were statistically significant, meaning that the hypothesis that interventions to improve diabetes self-management results in increased QOL was supported. Control subjects did not experience improved QOL while participating in studies. Conclusions These findings document that people with diabetes experience improved QOL from participation in diabetes self-management training programs. Future diabetes self-management intervention studies should include quality of life outcomes so that this important outcome can be further studied. After more primary studies are available, future meta-analyses can explore important moderator analyses.

Nursing home care quality: a multidimensional theoretical model integrating the views of consumers and providers.

This exploratory study was undertaken to discover the defining dimensions of nursing home care quality from the viewpoint of consumers of nursing home care. Eleven focus groups were conducted in five Missouri communities. The seven dimensions of the consumer multidimensional model of nursing home care quality are: staff, care, family involvement, communication, environment, home, and cost. The views of consumers and families are compared with the results of a previous study of providers of nursing home services. An integrated, multidimensional theoretical model is presented for testing and evaluation. An instrument based on the model is being tested to observe and score the dimensions of nursing home care quality.