In meta-analysis, the usual way of assessing whether a set of single studies is homogeneous is by means of the Q test. However, the Q test only informs meta-analysts about the presence versus the absence of heterogeneity, but it does not report on the extent of such heterogeneity. Recently, the I 2 index has been proposed to quantify the degree of heterogeneity in a meta-analysis. In this article, the performances of the Q test and the confidence interval around the I 2 index are compared by means of a Monte Carlo simulation. The results show the utility of the I 2 index as a complement to the Q test, although it has the same problems of power with a small number of studies.

BackgroundMeta-analyses of antidepressant medications have reported only modest benefits over placebo treatment, and when unpublished trial data are included, the benefit falls below accepted criteria for clinical significance. Yet, the efficacy of the antidepressants may also depend on the severity of initial depression scores. The purpose of this analysis is to establish the relation of baseline severity and antidepressant efficacy using a relevant dataset of published and unpublished clinical trials.Methods and FindingsWe obtained data on all clinical trials submitted to the US Food and Drug Administration (FDA) for the licensing of the four new-generation antidepressants for which full datasets were available. We then used meta-analytic techniques to assess linear and quadratic effects of initial severity on improvement scores for drug and placebo groups and on drug–placebo difference scores. Drug–placebo differences increased as a function of initial severity, rising from virtually no difference at moderate levels of initial depression to a relatively small difference for patients with very severe depression, reaching conventional criteria for clinical significance only for patients at the upper end of the very severely depressed category. Meta-regression analyses indicated that the relation of baseline severity and improvement was curvilinear in drug groups and showed a strong, negative linear component in placebo groups.ConclusionsDrug–placebo differences in antidepressant efficacy increase as a function of baseline severity, but are relatively small even for severely depressed patients. The relationship between initial severity and antidepressant efficacy is attributable to decreased responsiveness to placebo among very severely depressed patients, rather than to increased responsiveness to medication.

Background: The purpose of this meta-analysis was to explore the efficacy of exercise as a nonpharmacologic intervention to reduce cancer-related fatigue (CRF) among adult cancer survivors. We also investigated how different components of the exercise prescription (Ex R x ), methodologic considerations, and subject characteristics modulate CRF.Methods: A systematic search for randomized controlled trials was conducted using words related to cancer, exercise, and fatigue.Results: In total, 44 studies with 48 interventions qualified, including 3,254 participants of varying cancer types, stages of diagnosis, treatments, and exercise interventions. Cancer survivors in exercise interventions reduced their CRF levels to a greater extent than usual care controls, d þ ¼ 0.31 (95% CI ¼ 0.22-0.40), an effect that appeared to generalize across several types of cancer. CRF levels improved in direct proportion to the intensity of resistance exercise (b ¼ 0.60, P ¼ 0.01), a pattern that was stronger in higher quality studies (b ¼ 0.23, P < 0.05). CRF levels also reduced to a greater extent when interventions were theoretically driven (b ¼ 0.48, P < 0.001) or cancer survivors were older (b ¼ 0.24, P ¼ 0.04).Conclusions: Exercise reduced CRF especially in programs that involved moderate-intensity, resistance exercise among older cancer survivors and that were guided by theory.Impact: Our results indicate exercise interventions for adult cancer survivors should be multi-dimensional and individualized according to health outcome and cancer type. Cancer Epidemiol Biomarkers Prev; 20(1); 123-33.

This meta-analysis synthesizes eighty-four observational studies, conducted across twenty countries, to determine the mean proportion of people who reported ≥90% adherence to prescribed highly active antiretroviral therapy (HAART) and to identify the factors associated with high levels of adherence. Eight electronic databases were searched to locate all relevant studies available by January 2010, which were then coded for sample characteristics and adherence levels. The average rate of reporting ≥90% adherent HAART adherence is 62%. However, this proportion varies greatly across studies. In particular, a greater proportion of individuals maintaining ≥90% adherence to HAART is more likely in studies with higher proportions of men who have sex with men (MSM) and lower proportions of injection drug users (IDU), with participants in an earlier stage of infection, and in studies conducted in countries characterized by lower Human Development Index (HDI) scores.

Background Exercise improves quality of life (QOL) in cancer survivors, although characteristics of efficacious exercise interventions for this population have not been identified. Purpose The present meta-analysis examines the efficacy of exercise interventions in improving QOL in cancer survivors, as well as features that may moderate such effects. Method Studies were identified and coded, and QOL effect sizes were calculated and analyzed for trends. Results Overall, exercise interventions increased QOL, but this tendency depended to some extent on exercise and patient features. Although several features were associated with effect sizes, models revealed that interventions were particularly successful if they targeted more intense aerobic exercise and addressed women. These tendencies emerged over longer periods of time and were more prominent in studies with higher methodological quality. Conclusion Appropriately designed exercise interventions enhance QOL for cancer survivors and this pattern is especially evident for women. Limitations are discussed.

Chemosensory problems challenge health through diminished ability to detect warning odors, consume a healthy diet, and maintain quality of life. We examined the prevalence and associated risk factors of self-reported chemosensory alterations in 3603 community-dwelling adults (aged 40+ years), from the nationally representative, US National Health and Nutrition Examination Survey (NHANES) 2011-2012. In this new NHANES component, technicians surveyed adults in the home about perceived smell and taste problems, distortions, and diminished abilities since age 25 (termed "alterations"), and chemosensory-related health risks and behaviors. The prevalence of self-reported smell alteration was 23%, including phantosmia at 6%; taste was 19%, including dysgeusia at 5%. Prevalence rates increased progressively with age, highest in those aged 80+ years (smell, 32%; taste, 27%). In multivariable logistic regression, controlling for sociodemographics, health behaviors, and chemosensory-related conditions, the strongest independent risk factor for smell alteration was sinonasal symptoms (odds ratio [OR] = 2.06; 95% confidence interval [CI]: 1.63-2.61), followed by heavy drinking, loss of consciousness from head injury, family income ≤110% poverty threshold, and xerostomia. For taste, the strongest risk factor was xerostomia (OR = 2.65; 95% CI: 1.97-3.56), followed by nose/facial injury, lower educational attainment, and fair/poor health. Self-reported chemosensory alterations are prevalent in US adults, supporting increased attention to decreasing their modifiable risks, managing safety/health consequences, and expanding chemosensory screening/testing and treatments.

BackgroundAerobic exercise (AE) is recommended as first‐line antihypertensive lifestyle therapy based on strong evidence showing that it lowers blood pressure (BP) 5 to 7 mm Hg among adults with hypertension. Because of weaker evidence showing that dynamic resistance training (RT) reduces BP 2 to 3 mm Hg among adults with hypertension, it is recommended as adjuvant lifestyle therapy to AE training. Yet, existing evidence suggests that dynamic RT can lower BP as much or more than AE.Methods and ResultsWe meta‐analyzed 64 controlled studies (71 interventions) to determine the efficacy of dynamic RT as stand‐alone antihypertensive therapy. Participants (N=2344) were white (57%), middle‐aged (47.2±19.0 years), and overweight (26.8±3.4 kg/m2) adults with prehypertension (126.7±10.3/76.8±8.7 mm Hg); 15% were on antihypertensive medication. Overall, moderate‐intensity dynamic RT was performed 2.8±0.6 days/week for 14.4±7.9 weeks and elicited small‐to‐moderate reductions in systolic BP (SBP; d+=−0.31; 95% CIs, −0.43, −0.19; −3.0 mm Hg) and diastolic BP (DBP; d+=−0.30; 95% CIs, −0.38, −0.18; −2.1 mm Hg) compared to controls (Ps<0.001). Greater BP reductions occurred among samples with higher resting SBP/DBP: ≈6/5 mm Hg for hypertension, ≈3/3 mm Hg for prehypertension, and ≈0/1 mm Hg for normal BP (Ps<0.023). Furthermore, nonwhite samples with hypertension experienced BP reductions that were approximately twice the magnitude of those previously reported following AE training (−14.3 mm Hg [95% CIs, −19.0, −9.4]/−10.3 mm Hg [95% CIs, −14.5, −6.2]).ConclusionsOur results indicate that for nonwhite adult samples with hypertension, dynamic RT may elicit BP reductions that are comparable to or greater than those reportedly achieved with AE training. Dynamic RT should be further investigated as a viable stand‐alone therapeutic exercise option for adult populations with high BP.

IntroductionThe purpose of this meta-analysis was to examine the efficacy of exercise to reduce depressive symptoms among cancer survivors. In addition, we examined the extent to which exercise dose and clinical characteristics of cancer survivors influence the relationship between exercise and reductions in depressive symptoms.MethodsWe conducted a systematic search identifying randomized controlled trials of exercise interventions among adult cancer survivors, examining depressive symptoms as an outcome. We calculated effect sizes for each study and performed weighted multiple regression moderator analysis.ResultsWe identified 40 exercise interventions including 2,929 cancer survivors. Diverse groups of cancer survivors were examined in seven exercise interventions; breast cancer survivors were examined in 26; prostate cancer, leukemia, and lymphoma were examined in two; and colorectal cancer in one. Cancer survivors who completed an exercise intervention reduced depression more than controls, d + = −0.13 (95% CI: −0.26, −0.01). Increases in weekly volume of aerobic exercise reduced depressive symptoms in dose-response fashion (β = −0.24, p = 0.03), a pattern evident only in higher quality trials. Exercise reduced depressive symptoms most when exercise sessions were supervised (β = −0.26, p = 0.01) and when cancer survivors were between 47–62 yr (β = 0.27, p = 0.01).ConclusionExercise training provides a small overall reduction in depressive symptoms among cancer survivors but one that increased in dose-response fashion with weekly volume of aerobic exercise in high quality trials. Depressive symptoms were reduced to the greatest degree among breast cancer survivors, among cancer survivors aged between 47–62 yr, or when exercise sessions were supervised.