Publication selection bias in minimum-wage research? A meta-regression analysis

Card and Krueger's meta-analysis of the employment effects of minimum wages challenged existing theory. Unfortunately, their meta-analysis confused publication selection with the absence of a genuine empirical effect. We apply recently developed meta-analysis methods to 64 US minimum-wage studies and corroborate that Card and Krueger's findings were nevertheless correct. The minimum-wage effects literature is contaminated by publication selection bias, which we estimate to be slightly larger than the average reported minimum-wage effect. Once this publication selection is corrected, little or no evidence of a negative association between minimum wages and employment remains.<br />

Meta-regression analysis as the socio-economics of economics research

Meta-regression analysis (MRA) provides an empirical framework through which to integrate disparate economics research results, filter out likely publication selection bias, and explain their wide variation using socio-economic and econometric explanatory variables. In dozens of applications, MRA has found excess variation among reported research findings, some of which is explained by socio-economic variables (e.g., researchers&rsquo; gender). MRA can empirically model and test socio-economic theories about economics research. Here, we make two strong claims: socio-economic MRAs, broadly conceived, explain much of the excess variation routinely found in empirical economics research; whereas, any other type of literature review (or summary) is biased.<br />

Aid effectiveness on growth : a meta study

The aid effectiveness literature contains about 100 papers that see aid as a treatment given to poor countries to generate development. 68 of these papers provide a total of 543 comparable estimates of the effect of aid on growth, which are the data of our meta-analysis. We consider two questions: (Q1) Are the estimates converging to a clear result over time as aid agencies gain experience, models become better and data accumulates? We find that the results do have a positive average, but it is small, insignificant and falling. (Q2) Can we identify the main factors that explain the large differences in the results? We find that much of the variation between studies can be attributed to publication outlet, institutional affiliation, data and specification differences. However, some of the difference between studies is real. In particular, the aid-growth effect is stronger for Asian countries. The meta-analysis indicates also the existence of indirect channels, which need to be further explored.<br />

Does the UK minimum wage reduce employment? A meta-regression analysis

The employment effect from raising the minimum wage has long been studied but remains in dispute. Our meta-analysis of 236 estimated minimum wage elasticities and 710 partial correlation coefficients from 16 UK studies finds no overall practically significant adverse employment effect. Unlike US studies, there seems to be little, if any, overall reporting bias. Multivariate meta-regression analysis identifies several research dimensions that are associated with differential employment effects. In particular, the residential home care industry may exhibit a genuinely adverse employment effect.

Risk factors for violence in psychosis: systematic review and meta-regression analysis of 110 studies

Background<br /><br />Previous reviews on risk and protective factors for violence in psychosis have produced contrasting findings. There is therefore a need to clarify the direction and strength of association of risk and protective factors for violent outcomes in individuals with psychosis.<br /><br />Method<br /><br />We conducted a systematic review and meta-analysis using 6 electronic databases (CINAHL, EBSCO, EMBASE, Global Health, PsycINFO, PUBMED) and Google Scholar. Studies were identified that reported factors associated with violence in adults diagnosed, using DSM or ICD criteria, with schizophrenia and other psychoses. We considered non-English language studies and dissertations. Risk and protective factors were meta-analysed if reported in three or more primary studies. Meta-regression examined sources of heterogeneity. A novel meta-epidemiological approach was used to group similar risk factors into one of 10 domains. Sub-group analyses were then used to investigate whether risk domains differed for studies reporting severe violence (rather than aggression or hostility) and studies based in inpatient (rather than outpatient) settings.<br /><br />Findings<br /><br />There were 110 eligible studies reporting on 45,533 individuals, 8,439 (18.5%) of whom were violent. A total of 39,995 (87.8%) were diagnosed with schizophrenia, 209 (0.4%) were diagnosed with bipolar disorder, and 5,329 (11.8%) were diagnosed with other psychoses. Dynamic (or modifiable) risk factors included hostile behaviour, recent drug misuse, non-adherence with psychological therapies (p values&lt;0.001), higher poor impulse control scores, recent substance misuse, recent alcohol misuse (p values&lt;0.01), and non-adherence with medication (p value &lt;0.05). We also examined a number of static factors, the strongest of which were criminal history factors. When restricting outcomes to severe violence, these associations did not change materially. In studies investigating inpatient violence, associations differed in strength but not direction.<br /><br />Conclusion<br /><br />Certain dynamic risk factors are strongly associated with increased violence risk in individuals with psychosis and their role in risk assessment and management warrants further examination.<br />

Self-practice and self-reflection in training of psychological interventions and therapist skills development: A qualitative meta-synthesis review

&copy; 2015 Australian Psychological Society. Objective: The use of self-practice and self-reflection has been proposed as an efficacious strategy in the training of therapists. It has been argued to enhance therapist skills, and a key factor in the development of expertise. This systematic literature review investigated the effect of self-practice and self-reflection on therapist skills development. Method: Studies were identified through Medline, Academic Search Complete, PsychINFO, PsycARTICLES, Proquest, ISI, CINAHL, Cochrane, and Scopus databases. Additional studies were identified through lateral searches of relevant papers' reference lists and direct correspondence with authors of unpublished material. The selection criteria were studies that investigated the effect of self-practice and/or self-reflection on therapist skill development. There was no restriction on sample sizes, design of studies, dates of publication, or peer-reviewed papers. All studies were published in English. Results: Ten studies were included in this review. A thematic analysis was undertaken to analyse qualitative data. Due to inconsistency in the variables investigated across the quantitative studies, quantitative results were not subject to a meta-analysis but simply reported. Finally, qualitative and quantitative data were juxtaposed in a meta-synthesis. Conclusion: The meta-synthesis revealed inconsistencies between the qualitative and quantitative literature and a gap in relation to declarative knowledge. Methodological limitations across studies are discussed and recommendations for future research provided.