Effectiveness of grief therapy: A meta-analysis.

This meta-analysis addressed the question of how effective grief therapy is and for whom, using B. J. Becker's (1988) techniques for analyzing standardized mean-change scores. Analyses were based on 35 studies (N?=?2,284), with a weighted mean effect size (ES) of δ+?=?0.43 (95% confidence interval?=?0.33 to 0.52). Clients in no-treatment control groups showed little improvement (d=?=?0.06), possibly because of the relatively long delay between loss and treatment in most studies (mean delay?=?27 months). Moderators of treatment efficacy included time since loss and relationship to the deceased. Client selection procedures, a methodological factor not originally coded in this meta-analysis, appeared to contribute strongly to variability in ESs: a small number of studies involving self-selected clients produced relatively large ESs, whereas the majority of studies involving clients recruited by the investigators produced ESs in the small to moderate range. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Time to let go of the illusion that psychotherapy extends the survival of cancer patients: Reply to Kraemer, Kuchler, and Spiegel (2009).

Replies to comments from Kraemer, Kuchler, and Spiegel (see record 2009-02580-001) on the authors original article Psychotherapy and survival in cancer: The conflict between hope and evidence (see record 2007-06095-001). The authors recently reviewed evidence related to the notion that psychotherapy extends survival in cancer patients (J. C. Coyne, M. Stefanek, & S. C. Palmer, 2007). The authors found that no study to date, including several designed and powered to test this hypothesis, can be reasonably interpreted as evidence that cancer patients live longer as a result of receiving psychotherapy. The authors concluded that the evidence against psychotherapy as a life-prolonging intervention in cancer is sufficiently robust to discontinue funding studies in this area. H. C. Kraemer, T. Kuchler, and D. Spiegel (2009) critiqued the authors' review. The authors respond directly to numerous misrepresentations made by Kraemer et al. More importantly, the authors provide readers with an accurate overview of the main issues being debated and the reasons for their conclusions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of Behavioral Marital Therapy: A Meta-Analysis of Randomized Controlled Trials.

This meta-analysis summarizes results from 30 randomized experiments that compare behavioral marital therapy with no-treatment control with distressed couples. Results showed that behavioral marital therapy is significantly more effective than no treatment (d=.585). Although behavioral marital therapy research studies tend to be conducted under conditions that are less clinically representative than other samples of studies, representativeness was not significantly related to outcome. However, evidence also suggested that publication bias may exist in this literature whereby small sample studies with small effects are systematically missing compared with other studies. This bias may inflate the effects of behavioral marital therapies reported in previous meta-analyses, though we also explore a number of alternative explanations for this small sample bias. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nonparametric effect size estimation: A comment on Kraemer and Andrews.

Responds to H. C. Kraemer and G. Andrews's (see record 1982-11171-001) proposal of a nonparametric effect size D as an alternative to a parametric effect size proposed by G. V. Glass (1976). Here examples are given that illustrate that the measure D depends on the form of the underlying bivariate distribution of the pre- and posttreatment responses. This can result in a bias for conclusions based on D. An alternative nonparametric measure of effect size is proposed that avoids this difficulty. (2 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nonparametric estimators of effect size in meta-analysis.

When observations are normally distributed, the sample standardized mean difference is a consistent and asymptotically efficient estimator of effect size in meta-analysis. However, in some cases the observations are far from normally distributed, and a nonparametric index of effect magnitude is desirable. The logic of the estimator proposed by H. C. Kraemer and G. Andrews (see record 1982-11171-001) is extended to provide related nonparametric estimators of different parameters that may be appropriate under other experimental conditions. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Drugs as reinforcers-collaborative opportunities in epidemiology and behavioral pharmacology: Comment on Alessi, Roll, Reilly, and Johanson (2002).

Despite reliance on a relatively small sample, the study by S. M. Alessi, J. M. Roll, M. P. Reilly, and C.-E. Johanson (see record 2002-12827-002) yielded remarkably consistent results, indicating that drug preference can be switched using conditioning procedures. However, because the study included only adults with limited drug involvement, the findings need to be interpreted taking the nature of the sample into account. This limitation points to opportunities for collaboration between experimental and epidemiologic researchers. Specifically, nesting experimental studies within longitudinal epidemiologic studies would reduce the potential for bias in sample selection while providing experimental data that are usually not available in observational epidemiologic research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does psi exist? Comments on Milton and Wiseman's (1999) meta-analysis of Ganzfield research.

J. Milton and R. Wiseman (1999) attempted to replicate D. Bern and C. Honorton's (1994) meta-analysis, which yielded evidence that the ganzfeld is a suitable method for demonstrating anomalous communication. Using a database of 30 ganzfeld and autoganzfeld studies, Milton and Wiseman's meta-analysis yielded an effect size (ES) of only 0.013 (Stouffer Z?=?0.70, p?=?.24, one-tailed). Thus they failed to replicate Bem and Honorton's finding (ES?=?0.162, Stouffer Z?=?2.52, p?=?5.90?×?10-3, one-tailed). The authors conducted stepwise performance comparisons between all available databases of ganzfeld research. Larger aggregates of such studies were formed, including a database comprising 79 ganzfeld-autoganzfeld studies (ES?=?0.138, Stouffer Z?=?5.66, p?=?7.78?×?10-9). Thus Bern and Honorton's positive conclusion was confirmed. More accurate population parameters for the ganzfeld and autoganzfeld domains were calculated. Significant bidirectional psi effects were also found in all databases. The ganzfeld appears to be a replicable technique for producing psi effects in the laboratory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Two forms of minority-group test bias as psychometric artifacts with an animal model (Rattus norvegicus).

Controversy abounds over attributing group differences on tests to nature, nurture, or test bias. Limitations of correlational sampling from natural populations necessitate experimental methods to resolve underlying issues. In classicial psychometrics test items are selected from a larger item pool through analysis of item responses in a sample of subjects. Rats of six inbred strains (n?=?366) were tested in multiple mazes to provide a large item pool. Six populations were created, each with differing proportions of each strain. Items selected through independent item analyses within each population yielded six tests. An independent cross-validation sample (n?=?146) provided scores on all six items. This sample was also tested in another set of maze problems defined as the criterion to be predicted. Strain means and intrastrain predictive validities for the six tests varied with strain representation in the population used for item selection (p?     

A randomized controlled trial of the effects of group psychological therapy on survival in women with metastatic breast cancer

In order to test the effect of a psychological intervention on survival from cancer, 66 women with metastatic breast cancer, all receiving standard medical care, were randomly assigned into two groups; one group (n = 30) attended the psychological intervention, consisting of 35 weekly, 2 h sessions of supportive plus cognitive behavioral therapy; the control group (n = 36) received only a home study cognitive behavioral package. No significant difference was found in survival post-randomization between the groups as assessed by a log rank test 5 years after the commencement of the study. As expected, several prognostic factors were significant predictors of survival: metastatic site, hormonal receptor status, and chemotherapy prior to randomization. While many personal and demographic variables did not influence survival, there was a significant effect of self-reported exercise (possibly due to better health). A small subgroup of intervention subjects who attended outside support groups also survived significantly longer than those who did not. The strengths and limitations of the present study are discussed, and the results contrasted with those of a well known study by Spiegel et al. (Spiegel, D., Bloom, J.R., Kraemer, H.C. and Gottheil, E. (1989) Lancet ii, 888-891). We propose that a different experimental design (correlative) may be needed to show any effect of self-help behaviors and psychological attributes in a small minority of patients.     

Power to detect homework effects in psychotherapy outcome research.

Studies of homework effects in psychotherapy outcome have produced inconsistent results. Although these findings may reflect the comparability of psychotherapy with and without homework assignments, many of these studies may not have been sensitive enough to detect the effects sizes (ESs) likely to be found when examining homework effects. The present study evaluated the power of homework research and showed that, on average, current power levels are relatively weak in controlled studies ranging from 0.58 for large ESs to 0.09 for small ESs. Thus, inconsistent findings between studies may very well be due to low statistical power. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An examination of nonresponse in a work environment questionnaire mailed to psychiatric health care personnel.

Nonresponse to surveys, which seems to plague work environment studies and studies of health care personnel in particular, may pose problems of generalizability and validity. The aim of this study was to provide an estimate of nonresponse error in a self-administered survey concerning the work environment of psychiatric health care personnel. A random sample of 10% of the original survey population (N?=?693) was selected to participate in a telephone follow-up of a postal survey that had a response rate of 51%. There were no differences between the responders and nonresponders to the postal survey on the exposure or outcome variables. There was no evidence of nonresponse bias in this study, although recall bias may have been a problem. In those cases in which generalizability is deemed important, it is recommended that nonresponse studies be regularly carried out when response rates are less than 100%. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Confidence intervals for effect sizes: Compliance and clinical significance in the Journal of Consulting and Clinical Psychology..

Objective: In 2005, the Journal of Consulting and Clinical Psychology (JCCP) became the first American Psychological Association (APA) journal to require statistical measures of clinical significance, plus effect sizes (ESs) and associated confidence intervals (CIs), for primary outcomes (La Greca, 2005). As this represents the single largest editorial effort to improve statistical reporting practices in any APA journal in at least a decade, in this article we investigate the efficacy of that change. Method: All intervention studies published in JCCP in 2003, 2004, 2007, and 2008 were reviewed. Each article was coded for method of clinical significance, type of ES, and type of associated CI, broken down by statistical test (F, t, chi-square, r/R2, and multivariate modeling). Results: By 2008, clinical significance compliance was 75% (up from 31%), with 94% of studies reporting some measure of ES (reporting improved for individual statistical tests ranging from η2 = .05 to .17, with reasonable CIs). Reporting of CIs for ESs also improved, although only to 40%. Also, the vast majority of reported CIs used approximations, which become progressively less accurate for smaller sample sizes and larger ESs (cf. Algina & Kessleman, 2003). Conclusions: Changes are near asymptote for ESs and clinical significance, but CIs lag behind. As CIs for ESs are required for primary outcomes, we show how to compute CIs for the vast majority of ESs reported in JCCP, with an example of how to use CIs for ESs as a method to assess clinical significance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evaluating the circumplexity of interpersonal traits and the manifestation of interpersonal traits in interpersonal trust.

Two studies assessed the goodness of fit of ideal, quasi-, and noncircumplex models of interpersonal traits. Study 1 (N?=?132) represents a secondary data analysis using J.S. Wiggins's (1979) original Interpersonal Adjectives Scales (IAS) and reported by J.S. Wiggins, J.H. Steiger, and L. Gaelick (1981). Study 2 (N?=?401) represents a primary data analysis using Wiggins's revised IAS (J.S. Wiggins, P. Trapnell, & N. Phillips, 1988). Results of both studies indicated that a quasi-circumplex model provided a better fit to the correlational data than did either ideal or noncircumplex models. Also, in Study 2, results for a subsample (n?=?113) indicated that an ideal circumplex model yielded a significant positive path coefficient from Nurturance to interpersonal trust (J.K. Rempel, J.G. Holmes, & M.P. Zanna, 1985) but not from Dominance to interpersonal trust, whereas a quasi-circumplex model yielded significant positive paths from both Dominance and Nurturance to interpersonal trust. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"What, can the devill speake true?"

Replies to M. H. Birmbaum (see record 1973-20037-001), who argued that the correlation coefficient has the power to mislead and is, therefore, an instrument of the devil, who can be exorcised only by an application of functional measurement. It is noted that Birnbaum's conclusions may satisfy the tests of J. Sprenger and H. Kraemer in Malleus Maleficarum (1489), but they do not follow from logical analysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Microstructure characteristics of 12Cr ferritic/martensitic steels with various yttrium additions

12Cr ferritic/martensitic steels with 0, 0.1 wt%, 0.2 wt% and 0.3 wt% theoretical yttrium (Y) additions were fabricated by vacuum inducting melting and casting method. Solubilities of Y in the 12Cr steels are 0.027, 0.078 and 0.17 for 12Cr-0.1Y, 12Cr-0.2Y and 12Cr-0.3Y, respectively. Phase transformations and microstructure characteristics under different heat-treatment schedules were investigated. The starting temperature of ferrite-to-austenite transformation A_c1 are maintained about 850 °C, but the finishing temperature of ferrite-to-austenite transformation A_c3 are about 950, 970, 980 and 1000 °C for 12Cr-0Y, 12Cr-0.1Y, 12Cr-0.2Y and 12Cr-0.3Y, respectively, which indicates that A_c3 increases gradually with the addition of Y. Martensite accompanied with a few δ-ferrite is the dominant structure in all the steels. The amount of δ-ferrite shows a strong dependence with the Y content and austenitizing temperature. Area fraction of δ-ferrite increases with the content of Y, which is the ferrite favouring element. The minimum amount of δ-ferrite are achieved at 950 °C for 12Cr-0Y, 12Cr-0.1Y, 12Cr-0.2Y and 1000 °C for 12Cr-0.3Y. Besides, more carbides precipitate along the martensite laths and grain boundaries in the Y-bearing steel due to the redistribution of carbon between austenite and ferrite resulting from the ferrite favouring element of Y.     

The magical number .7?±?.2: Meta-meta-analysis of the probability of superior outcome in comparisons involving therapy, placebo, and control.

The "probability of superiority estimate" (PS) estimates the probability that a randomly sampled client from a population given a treatment will have an outcome that is superior to that of a randomly sampled client from a population given another treatment. The meta-analytic clinical outcome literature was examined to calculate mean PS (PS) for comparisons involving therapy versus control, the raw versus placebo, therapy versus therapy, and placebo versus control. The range of PS was found to be approximately .7?±?.2, with median PS greatest when therapy and control are compared ( Mdn PSTC?=?.70, where T?=?therapy and C?=?control) and least when 2 therapies are compared ( Mdn PSTT?=?.56). Results suggested that there is more to therapeutic success than placebo effects ( Mdn PSTP?=?.66, where T?=?therapy and P?=?placebo) and that placebo is typically better than do-nothing control conditions ( Mdn PSPC?=?.62). The present exceptionally large study, controlling for dependencies and confounding variables, may put to rest the question of the superiority of therapy to placebo. It also appears that the strength of effect of therapy is typically at least average among the effects of independent variables in psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thermal unfolding of dodecameric glutamine synthetase: inhibition of aggregation by urea

Thermal unfolding of dodecameric manganese glutamine synthetase (622,000 M(r)) at pH 7 and approximately 0.02 ionic strength occurs in two observable steps: a small reversible transition (Tm approximately 42 degrees C; delta H approximately equal to 0.9 J/g) followed by a large irreversible transition (Tm approximately 81 degrees C; delta H approximately equal to 23.4 J/g) in which secondary structure is lost and soluble aggregates form. Secondary structure, hydrophobicity, and oligomeric structure of the equilibrium intermediate are the same as for the native protein, whereas some aromatic residues are more exposed. Urea (3 M) destabilizes the dodecamer (with a tertiary structure similar to that without urea at 55 degrees C) and inhibits aggregation accompanying unfolding at < or = 0.2 mg protein/mL. With increasing temperature (30-70 degrees C) or incubation times at 25 degrees C (5-35 h) in 3 M urea, only dodecamer and unfolded monomer are detected. In addition, the loss in enzyme secondary structure is pseudo-first-order (t1/2 = 1,030 s at 20.0 degrees C in 4.5 M urea). Differential scanning calorimetry of the enzyme in 3 M urea shows one endotherm (Tmax approximately 64 degrees C; delta H = 17 +/- 2 J/g). The enthalpy change for dissociation and unfolding agrees with that determined by urea titrations by isothermal calorimetry (delta H = 57 +/- 15 J/g; Zolkiewski M, Nosworthy NJ, Ginsburg A, 1995, Protein Sci 4: 1544-1552), after correcting for the binding of urea to protein sites exposed during unfolding (-42 J/g). Refolding and assembly to active enzyme occurs upon dilution of urea after thermal unfolding.     

Two new procedures for studying validity generalization.

Several Monte Carlo studies examined the accuracy of 2 new procedures in estimating population true validity mean and variance. Results indicate that 1 of the new procedures provided slightly more accurate estimates than the procedures of F. L. Schmidt and J. E. Hunter (see record 1978-11448-001) and J. C. Callender and H. G. Osburn (see record 1981-00257-001). From a practical point of view, however, the estimates from the various procedures were quite comparable. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does psi exist? Lack of replication of an anomalous process of information transfer.

D. J. Bern and C. Honorton (1994) recently presented in this journal a set of ganzfeld extrasensory perception (ESP) experiments conducted by C. Honorton that appeared to support the existence of a communication anomaly. In this article, the authors present a meta analysis of 30 ganzfeld ESP studies from 7 independent laboratories adhering to the same stringent methodological guidelines that C. Honorton followed. The studies failed to confirm his main effect of participants scoring above change on the ESP task, Souffer z?=?0.70, p?=?.24, one-tailed; M effect size (z/N1/2)?=?0.013, SD?=?0.23. The new studies included replication attempts of 3 out of 5 internal effects reported as statistically significant by D. J. Bern and C. Honorton. Only 1 was confirmed, and the authors found the D. J. Bern and C. Honorton were mistaken in describing the original effect as being statistically significant. The authors conclude that the ganzfeld technique does not at present offer a replicable method for producing ESP in the laboratory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of White, African American, Hispanic, and Asian children on the Naglieri Nonverbal Ability Test.

This study examined differences between 3 matched samples of White (n?=?2,306) and African American (n?=?2,306), White (n?=?1,176) and Hispanic (n?=?1,176), and White (n?=?466) and Asian (n?=?466) children on the Naglieri Nonverbal Ability Test (NNAT; J. A. Naglieri, 1997a). The groups were selected from 22,620 children included in the NNAT standardization sample and matched on geographic region, socioeconomic status, ethnicity, and type of school setting (public or private). There was only a small difference between the NNAT scores for the White and African American samples (d ratio?=?.25) and minimal differences between the White and Hispanic (d ratio?=?.17) and between the White and Asian (d ratio?=?.02) groups. The NNAT was moderately correlated with achievement for the total sample and correlated similarly with achievement for the White and ethnic minority groups. The median correlation of NNAT with reading was .52 and NNAT with math was .63 across the samples. Results suggest that the NNAT scores have use for fair assessment of White and minority children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)