Estimating the sample mean and standard deviation from commonly reported quantiles in meta-analysis

Researchers increasingly use meta-analysis to synthesize the results of several studies in order to estimate a common effect. When the outcome variable is continuous, standard meta-analytic approaches assume that the primary studies report the sample mean and standard deviation of the outcome. However, when the outcome is skewed, authors sometimes summarize the data by reporting the sample median and one or both of (i) the minimum and maximum values and (ii) the first and third quartiles, but do not report the mean or standard deviation. To include these studies in meta-analysis, several methods have been developed to estimate the sample mean and standard deviation from the reported summary data. A major limitation of these widely used methods is that they assume that the outcome distribution is normal, which is unlikely to be tenable for studies reporting medians. We propose two novel approaches to estimate the sample mean and standard deviation when data are suspected to be non-normal. Our simulation results and empirical assessments show that the proposed methods often perform better than the existing methods when applied to non-normal data

Big boys don't cry: Depression and men

Men are a numerical minority group receiving a diagnosis of, and treatment for, depression. However, community surveys of men and of their mental health issues (e.g. suicide and alcoholism) have led some to suggest that many more men have depression than are currently seen in healthcare services. This article explores current approaches to men and depression, which draw on theories of sex differences, gender roles and hegemonic masculinity. The sex differences approach has the potential to provide diagnostic tools for (male) depression; gender role theory could be used to redesign health services so that they target individuals who have a masculine, problem-focused coping style; and hegemonic masculinity highlights how gender is enacted through depression and that men’s depression may be visible in abusive, aggressive and violent practices. Depression in men is receiving growing recognition, and recent policy changes in the UK may mean that health services are obliged to incorporate services that meet the needs of men with depression

Continuum Belief, Categorical Belief, and Depression Stigma: Correlational Evidence and Outcomes of an Online Intervention

Continuum belief interventions that erode boundaries between “normal” individuals and individuals with psychiatric problems may help to reduce psychiatric stigma, but a number of questions persist. The magnitude of belief change attributable to the intervention is unclear. Moreover, most studies have executed continuum interventions to reduce stigma of schizophrenia, and all studies have examined intervention effects on only public stigma. This study utilized a large sample (n = 654) to examine effects of a continuum intervention on depression stigma—public stigma in the full sample and self-stigma among participants with a self-reported history of depression. Participants were randomly assigned to one of three intervention groups: (a) the control group, which read material that merely described depression, (b) the continuum group, which read material that attested to a continuum view of depression, or (c) the categorical group, which read material that attested to a categorical view of depression. Correlational analyses demonstrated that preintervention categorical belief positively predicted, and preintervention continuum belief negatively predicted, depression stigma. Moreover, preintervention categorical belief positively predicted, and preintervention continuum belief negatively predicted, self-stigma among participants with a self-reported history of depression. There was scant evidence that the intervention affected public stigma among participants without a history of depression and no evidence that it affected self-stigma among participants with a history of depression. These findings illuminate a number of key priorities for future research on continuum belief intervention and its prospects for stigma reduction

Association of N-terminal pro-brain natriuretic peptide with cognitive function and depression in elderly people with type 2 diabetes

<p>Background: Type 2 diabetes mellitus is associated with risk of congestive heart failure (CHF), cognitive dysfunction and depression. CHF itself is linked both to poor cognition and depression. The ventricular N-terminal pro-brain natriuretic peptide (NT-proBNP) is a marker of CHF, suggesting potential as a marker for cognitive impairment and/or depression. This was tested in the Edinburgh Type 2 Diabetes Study (ET2DS).</p> <p>Methodology and Principal Findings: Cross-sectional analysis of 1066 men and women aged 60–75 with type 2 diabetes. Results from seven neuropsychological tests were combined in a standardised general cognitive ability factor, ‘g’. A vocabulary-based test estimated pre-morbid cognitive ability. The Hospital Anxiety and Depression Scale (HADS) assessed possible depression. After adjustment for age and sex, raised plasma NT-proBNP was weakly associated with lower ‘g’ and higher depression scores (ß −0.09, 95% CI −0.13 to −0.03, p = 0.004 and ß 0.08, 95% CI 0.04 to 0.12, p<0.001, respectively). Comparing extreme quintiles of NT-proBNP, subjects in the highest quintile were more likely to have reduced cognitive ability (within the lowest tertile of ‘g’) and ‘possible’ depression (HADS depression ≥8) (OR 1.80; 95% CI: 1.20, 2.70; p = 0.005 and OR 2.18; 95% CI: 1.28, 3.71; p = 0.004, respectively). Associations persisted when pre-morbid ability was adjusted for, but as expected were no longer statistically significant following the adjustment for diabetes-related and vascular co-variates (β −0.02, 95% CI −0.07 to 0.03, p>0.05 for ‘g’; β 0.03, 95% CI −0.02 to 0.07, p>0.05 for depression scores).</p> <p>Conclusion: Raised plasma NT-proBNP was weakly but statistically significantly associated with poorer cognitive function and depression. The prospective phases of the ET2DS will help determine whether or not NT-proBNP can be considered a risk marker for subsequent cognitive impairment and incident depression and whether it provides additional information over and above traditional risk factors for these conditions.</p&gt

The Benefits of Physical Activity on Depression

Physical exercise can be an effective counter-measure against depression. Activity need not be strenuous and it may reduce the risk for depression, even among those with a family history or genetic disposition for depression. And depression in itself may not cause a reduction in physical activity. It could be that we will see health care providers increasingly prescribing doses of physical activity for our mental health

Religiosity, identity, and depression in late adolescence: A longitudinal study

In this study, longitudinal associations among religiosity, identity style, identity commitment, and depression were examined in a sample of late adolescents. Online survey data were collected in two waves with an approximate six-week interval. Correlations demonstrated that high levels of negative aspects of religiosity, such as negative religious coping, predicted high levels of depression. Other aspects of religiosity, such as positive religious coping, did not predict depression. In addition, high levels of diffuse-avoidant identity style predicted high levels of depression, and high levels of identity commitment predicted low levels of depression. However, when a regression was performed with all the predictors of wave 2 depression and controlling for depression at wave 1, the predictors were no longer significant. Associations between identity and religiosity were also examined

Stress and depression among veterinary medical students

While existing literature suggests that professional students (e.g., medical, dental, law, nursing, etc.) experience high levels of stress and depression, the experiences of veterinary medical students have been less well examined. The purpose of this study was to explore the levels of stress and depression among veterinary medical students and to examine the relationship between these variables. Study participants were 1,245 veterinary medical students from North America. The findings provide support for the assertion that veterinary medical students experience high levels of stress and depression. Results also indicated that there is a correlation between stress and depression for veterinary medical students and that female students experience higher levels of stress and depression than their male counterparts.Accepted manuscrip