Two studies examining the negative effect of self-efficacy on performance

Although hundreds of studies have found a positive relationship between self-efficacy and performance, several studies have found a negative relationship when the analysis is done across time (repeated measures) rather than across individuals. W. T. Powers (1991) predicted this negative relationship based on perceptual control theory. Here, 2 studies are presented to (a) confirm the causal role of self-efficacy and (b) substantiate the explanation. In Study 1, self-efficacy was manipulated for 43 of 87 undergraduates on an analytic game. The manipulation was negatively related to performance on the next trial. In Study 2, 104 undergraduates played the analytic game and reported self-efficacy between each game and confidence in the degree to which they had assessed previous feedback. As expected, self-efficacy led to overconfidence and hence increased the likelihood of committing logic errors during the game.

Statistical power in randomized intervention studies with noncompliance

This study examined various factors that affect statistical power in randomized intervention studies with noncompliance. On the basis of Monte Carlo simulations, this study demonstrates how statistical power changes depending on compliance rate, study design, outcome distributions, and covariate information. It also examines how these factors influence power in different methods of estimating intervention effects. Intent-to-treat analysis and complier average causal effect estimation are compared as 2 alternative ways of estimating intervention effects under noncompliance. The results of this investigation provide practical implications in designing and evaluating intervention studies taking into account noncompliance.

Measurement of functional ability following traumatic brain injury using the Clinical Outcomes Variable Scale: a reliability study

This study determined the inter-tester and intra-tester reliability of physiotherapists measuring functional motor ability of traumatic brain injury clients using the Clinical Outcomes Variable Scale (COVS). To test inter-tester reliability, 14 physiotherapists scored the ability of 16 videotaped patients to execute the items that comprise the COVS. Intra-tester reliability was determined by four physiotherapists repeating their assessments after one week, and three months later. The intra-class correlation coefficients (ICC) were very high for both inter-tester reliability (ICC > 0.97 for total COVS scores, ICC > 0.93 for individual COVS items) and intra-tester reliability (ICC > 0 97). This study demonstrates that physiotherapists are reliable in the administration of the COVS.

Jointly modelling the relationship between survival and pulmonary function in cystic fibrosis patients

Modelling the relationship between pulmonary function and survival in cystic fibrosis (CF) is complicated by the fact that measures of pulmonary function commonly used such as the forced expiratory volume in one second (FEV(1)) are measured with error, and patients with the poorest lung function are increasingly censored by death, that is, data are available only for the patients who have survived to the current age. We assume a linear random effects model for FEV1 per cent predicted, where the random intercept and slope of FEV(1) per cent predicted, along with a specified transformation of the age at death follow a trivariate normal distribution. We illustrate how this model can be used to describe the relationship between age at death and parameters of the individual patient's regression of FEV(1) per cent predicted versus age, such as the slope and the intercept or true value of FEV(1) per cent predicted at a given age. We also illustrate how the model provides empirical Bayes estimates of these individual parameters. In particular, we explore how the predicted value of the age at death might be used as a prognostic or severity index. The model and methods are illustrated on a cohort of 188 cystic fibrosis patients with a common genotype (homozygous for the DeltaF508 mutation), born on or after 1965 and followed at the CF Center at the Rainbow Babies and Children's Hospital, Cleveland, OH, U.S.A.

Sample size requirements for estimating intraclass correlations with desired precision

A method is developed to calculate the approximate number of subjects required to obtain an exact confidence interval of desired width for certain types of intraclass correlations in one-way and two-way ANOVA models. The sample size approximation is shown to be very accurate.

Power dressing and meta-analysis: incorporating power analysis into meta-analysis

AIMS

This paper highlights the lack of consideration that is given to power in the health and social sciences, which is a continuing problem with both single study research and more importantly for meta-analysis.

BACKGROUND

The power of a study is the probability that it will lead to a statistically significant result. By ignoring power the single study researcher makes it difficult to get negative results published and therefore affects meta-analysis through publication bias. Researchers using meta-analysis, who also ignore power, then compound the problem by including studies with low power that are more likely to show significant effects.

METHOD

A simple means of calculating an easily understood measure of effect size from a contingency table is demonstrated in this paper. A computer programme for determining the power of a study is recommended and a method of reflecting the adequacy of the power of the studies in a meta-analysis is suggested. An example of this calculation from a meta-analytic study on intravenous magnesium, which produced inaccurate results, is provided.

CONCLUSION

It is demonstrated that incorporating power analysis into this meta-analysis would have prevented misleading conclusions being reached. Some suggestions are made for changes in the protocol of meta-analytic studies, which highlight the importance of power analysis.

Effect of harmonic relatedness on the detection of temporal asynchronies

Speeded intonation judgments of a target chord are facilitated when the chord is preceded by a harmonically related prime chord. The present study extends harmonic priming to temporal asynchrony judgments. In both tasks, the normative target chords (consonant, synchronous) are processed more quickly and accurately after a harmonically related prime than after a harmonically unrelated prime. However, the influence of harmonic context on sensitivity (d') differs between the two tasks: d' was higher in the related context for intonation judgments but was higher in the unrelated context for asynchrony judgments. A neural net model of tonal knowledge activation provides an explanatory framework for both the facilitation in the related contexts and the sensitivity differences between the tasks.

Abnormal P300 in a case of delusional misidentification with coinciding Capgras and Frégoli symptoms

The Delusional Misidentification Syndrome (DMS) is thought to be related to dissociation between recognition and identification processes. Working memory (WM) is considered responsible for the integration and online manipulation of information, so that it is available for further processing. Since the P300 component of event-related potentials (ERPs) is considered as an index of the on-line updating of WM, the present study is focused on auditory P300 elicited during a WM test in DMS, compared with that in healthy controls. ERPs, elicited during a WM test, in a case suffering from coinciding Capgras and Frégoli symptoms, were recorded. Peak amplitude and latency of the averaged P300 waveforms, as well as memory performance of this case, were compared to the patterns obtained from healthy controls. In relation to normal controls, the patient exhibited significantly attenuated amplitude of P300 at the F4, P3 and Pz abductions. The patient also showed significantly prolonged latencies of P300 at all abductions used. These findings suggest that DMS may be accompanied by WM dysfunction affecting brain regions outside the prefrontal cortex, as well as within, and by diffuse failure to allocate attention resources to a stimulus, as they are reflected by P300 amplitudes and latencies respectively. Additionally, it may be suggested that techniques designed to explore cognitive operations, such as recording of ERPs, and more specifically P300, during WM tasks, could provide further insights into the relationship between neural functioning and the cognitive deficits in DMS.

Clinical assessment

Are clinical psychologists' assessment practices cost-effective? Are they scientifically sound? Are they fair and unbiased? Financial pressures from managed care interests, recent developments in the law, and multicultural issues are forcing the profession to confront these hard questions regarding accountability. Our review discusses the important changes that have begun to alter the field of personality assessment and describes recent research on clinical judgment and its implications for the future. We conclude that clinical psychology can adapt to future conditions by developing assessment strategies that are economical, scientifically sound, and culturally sensitive.

Latent variables in psychology and the social sciences

The paper discusses the use of latent variables in psychology and social science research. Local independence, expected value true scores, and nondeterministic functions of observed variables are three types of definitions for latent variables. These definitions are reviewed and an alternative "sample realizations" definition is presented. Another section briefly describes identification, latent variable indeterminancy, and other properties common to models with latent variables. The paper then reviews the role of latent variables in multiple regression, probit and logistic regression, factor analysis, latent curve models, item response theory, latent class analysis, and structural equation models. Though these application areas are diverse, the paper highlights the similarities as well as the differences in the manner in which the latent variables are defined and used. It concludes with an evaluation of the different definitions of latent variables and their properties.

The transtheoretical model of behavior change: a meta-analysis of applications to physical activity and exercise

The purpose of this study was to summarize findings from empirical applications of the transtheoretical model (TTM) (Prochaska & DiClemente, 1983) in the physical activity domain by using the quantitative method of meta-analysis. Ninety-one independent samples from 71 published reports were located that present empirical data on at least one core construct of the TTM applied to exercise and physical activity. In general, results support the application because core constructs differ across stages and most changes are in the direction predicted by the theory. Three general conclusions are offered. First, existing data are unable to confirm whether physical activity behavior change occurs in a series ofstages that are qualitatively different or along adjacent segments of an underlying continuum. Second, the growing number of studies that incorporate TTM concepts means that there is an increasing need to standardize and improve the reliability of measurement. Finally, the role ofprocesses of change needs reexamining because the higher order constructs are not apparent in the physical activity domain and stage-by-process interactions are not evident. There now are sufficient data to confirm that stage membership is associated with different levels of physical activity, self-efficacy, pros and cons, and processes of change. Further studies that simply stage participants or examine cross-sectional differences between core constructs of the TTM are of limited use. Future research should examine the moderators and mediators of stage transition.

Comparison of two random-effects methods of meta-analysis

Two studies compared the Schmidt-Hunter method of meta-analysis (J. E. Hunter & F. L. Schmidt, 1990) with the method described by L. V. Hedges and J. L. Vevea (1998). Study 1 evaluated estimates of rho, sigmarho, and resulting credibility intervals for both models through Monte Carlo methods. Results showed slight differences between the 2 methods. In Study 2, a reanalysis of published meta-analyses using both methods with several artifact distributions showed that although both choice of technique and type of correction could matter, the technique of meta-analysis used is less influential on the study outcome than is the choice of artifact correction.

Prevention of eating disorders: challenges and opportunities

OBJECTIVE AND METHODS

On April 25, 2000, the National Institute of Mental Health (NIMH) convened a Roundtable on the Prevention of Eating Disorders to review the state of prevention science in eating disorders and formulate recommendations regarding future steps to be taken in this area of research.

RESULTS AND DISCUSSION

This report summarizes the roundtable discussion. The discussion focused on four major areas: the state of the art of risk factors research, translational research, prevention research in related fields, and cutting-edge efforts in eating disorder prevention.

CONCLUSIONS

The report concludes with specific recommendations.

Ein Fragebogen zur Erfassung der Ekelempfindlichkeit (FEE)

Zusammenfassung. Theoretischer Hintergrund: Bislang existierte noch kein Fragebogen zur Erfassung der Ekelempfindlichkeit in deutscher Sprache. Fragestellung: Entwicklung eines solchen Instrumentes. Methode: Ein vorläufiger Fragebogen wurde an 235 Probanden vergeben. Mit den Daten wurde eine Hauptachsenanalyse mit obliquer Rotation gerechnet. Die Überprüfung der Faktorenstruktur erfolgte mittels konfirmatorischer Faktorenanalyse (n = 501). Ergebnisse: Der Fragebogen zur Erfassung der Ekelempfindlichkeit (FEE) besteht aus 37 Items, die fünf Skalen bilden: Tod, Körperausscheidungen, Hygiene, Verdorbenes und orale Abwehr. Der FEE hat eine Reliabilität (Cronbachs α) von .90. Die Gesamtpunktwerte korrelierten positiv mit der Angst vor Blut und Verletzungen (r = .47) sowie der Zwanghaftigkeit der Probanden (r = .25). Schlussfolgerung: Dieses Ergebnis weist auf die mögliche Bedeutung der Ekelempfindlichkeit für die Entstehung und Aufrechterhaltung von Angststörungen wie Blutphobien und Zwängen hin.

Alterskorrelierte Unterschiede vs. Veränderungen intellektueller Leistungen: Sind beide durch die Speed-Variable erklärbar?

Zusammenfassung. Zur Erklärung kognitiver Entwicklung über die Lebensspanne geht eine “starke“ Version der Speed-Hypothese davon aus, dass alterskorrelierte Veränderungen der Informationsverarbeitungsgeschwindigkeit (Speed) alterskorrelierte Veränderungen und Unterschiede der intellektuellen Leistungsfähigkeit vorhersagen. Querschnittstudien, die die Beziehung zwischen Altersunterschieden in Speed und intellektueller Leistung untersuchen, unterstützen diese Hypothese. Nur wenige Längsschnittstudien haben bisher geprüft, in welchem Ausmaß Veränderungen in Speed und intellektueller Leistungsfähigkeit zueinander in Beziehung stehen. In der vorliegenden Studie wurde die starke Version der Speed-Hypothese mit Längsschnittdaten geprüft. Um zu untersuchen, ob Veränderungen in Speed und fluider Intelligenz korreliert sind, wurden Veränderungen in beiden Konstrukten modelliert und in Beziehung zueinander gesetzt. Für Daten von zwei Messzeitpunkten der Interdisziplinären Längsschnittstudie des Erwachsenenalters (ILSE) wurden mehrere strukturelle Differenzfaktorenmodelle berechnet. Die Ergebnisse belegen signifikante alterskorrelierte Verluste in Speed und intellektueller Leistung. Die Differenzfaktoren indizieren differenzielle Veränderungen in beiden Konstrukten. Die Veränderungen in Speed und fluider Intelligenz waren moderat korreliert. Unsere längsschnittlichen Ergebnisse legen eine “mittelstarke“ Version der Speed-Hypothese nahe: Obwohl Speed-Unterschiede den Großteil der Varianz in intellektuellen Leistungsunterschieden erklären, sind Speed-Veränderungen weniger gut geeignet, Altersveränderungen der intellektuellen Leistung vorherzusagen.

Reproducibility of quantitative dynamic MRI of normal human tissues

The aim of the study was to establish the normal range and to evaluate the reproducibility of dynamic contrast enhanced MRI (DCE-MRI) parameter estimates in normal human pelvic tissues. Nineteen patients with prostate cancer, undergoing androgen deprivation treatment, had paired DCE-MRI examinations of the pelvis using spoiled gradient-echo sequences. Quantitative enhancement parameters were calculated for each examination: transfer constant (K(trans)), leakage space (v(e)) and maximum contrast medium accumulation (MCMA) of pelvic muscles, bone marrow and fat. Descriptive and reproducibility statistics were calculated: within-patient standard deviation (wSD), repeatability and within-patient coefficient of variation (wCV). The femoral head and ischiorectal fat showed large numbers of non-enhancing pixels (81 and 88%, respectively). The ischial bone marrow had the highest values of kinetic parameter estimates (K(trans) 0.554 min(-1), v(e) 18.5% and MCMA 0.164 mmol/kg). Muscle parameters values were lower (K(trans) 0.126-0.137 min(-1), v(e) 10.6-11.5% and MCMA 0.077-0.086 mmol/kg). The mean difference between paired examinations was not significantly different from zero for any parameter. v(e) and MCMA had the lowest wCV (between 19 and 29%). For individuals, a log(10) K(trans) change of approximately 0.90 in muscles and 0.52 in the ischium would be statistically significant. The corresponding absolute changes for v(e) are 6.7% in muscle and 13.6% in the ischium. For a group of 19 patients, small changes are statistically significant (muscle log(10) K(trans) 0.208 and v(e) 1.5% and ischium log(10) K(trans) 0.123 and v(e) 3.1%). Fat and the femoral head are unreliable tissues from which to obtain kinetic parameter estimates due to poor enhancement. v(e) and MCMA have smaller coefficient of variation than K(trans) in muscles and ischium. Reproducibility studies of normal and pathological tissues should be incorporated into clinical research protocols that measure treatment effects by DCE-MRI techniques.

Business-unit-level relationship between employee satisfaction, employee engagement, and business outcomes: a meta-analysis

Based on 7,939 business units in 36 companies, this study used meta-analysis to examine the relationship at the business-unit level between employee satisfaction-engagement and the business-unit outcomes of customer satisfaction, productivity, profit, employee turnover, and accidents. Generalizable relationships large enough to have substantial practical value were found between unit-level employee satisfaction-engagement and these business-unit outcomes. One implication is that changes in management practices that increase employee satisfaction may increase business-unit outcomes, including profit.

An examination of interrater reliability for scoring the Rorschach Comprehensive System in eight data sets

In this article, we describe interrater reliability for the Comprehensive System (CS; Exner. 1993) in 8 relatively large samples, including (a) students, (b) experienced re- searchers, (c) clinicians, (d) clinicians and then researchers, (e) a composite clinical sample (i.e., a to d), and 3 samples in which randomly generated erroneous scores were substituted for (f) 10%, (g) 20%, or (h) 30% of the original responses. Across samples, 133 to 143 statistically stable CS scores had excellent reliability, with median intraclass correlations of.85, .96, .97, .95, .93, .95, .89, and .82, respectively. We also demonstrate reliability findings from this study closely match the results derived from a synthesis of prior research, CS summary scores are more reliable than scores assigned to individual responses, small samples are more likely to generate unstable and lower reliability estimates, and Meyer's (1997a) procedures for estimating response segment reliability were accurate. The CS can be scored reliably, but because scoring is the result of coder skills clinicians must conscientiously monitor their accuracy.

Data quality in evaluation of an alcohol-related harm prevention program

The authors report the reliability and convergent validity in a sample of college students for 27 composite scales and two items covering alcohol use, cigarette smoking, marijuana use, and other drug use; beliefs relating to alcohol use; perceived norms for alcohol-related behavior; harm prevention skills; intentions to take prevention action; harm prevention action taken; risk taken; experienced harm; and other health-related behaviors and person characteristics. Data quality assessment strategies and missing data procedures were illustrated for large, multivariate, longitudinal data sets. Results indicate 23 of the 27 composite scales had at least acceptable reliability, and the remaining 4 composite scales had at least marginally acceptable reliability. At least moderate construct validity was demonstrated for 25 scales.

Arbeit und Gesundheit:

Zusammenfassung. Der vorliegende Beitrag nimmt Stellung zu einigen grundsätzlichen Kontroversen, die für die Debatte über Arbeit und Gesundheit wesentlich sind. Zunächst wird diskutiert, ob ein Konzept objektiv bestimmbarer Stressoren und Ressourcen in der Arbeit angesichts der Individualität von Situationsbewertungen überhaupt sinnvoll ist. Dies wird bejaht, wenn man diese Merkmale im Sinne eines Risikofaktorenmodells begreift und kulturelle Gemeinsamkeiten in Bewertungsprozessen berücksichtigt. Im Hinblick auf die Frage, ob die gefundenen Zusammenhänge real sind oder auf Grund der häufigen Verwendung von Fragebögen eher Methodenartefakte widerspiegeln, wird aufgezeigt, daß sich auch bei Kontrolle konfundierender Einflüsse Effekte ergeben, die nicht auf Artefakte reduziert werden können. Als drittes wird dargestellt, daß hinter der - auch in diesem Bereich typischen - Varianzaufklärung von zehn Prozent durchaus substantielle Effekte stehen können, wenn man die involvierten relativen Risiken betrachtet. Und schließlich diskutieren wir das komplexe Verhältnis von personenbezogener versus organisationsbezogener Intervention und plädieren für eine stärkere Verzahnung beider Ansätze.

Effectiveness of mentoring programs for youth: a meta-analytic review

We used meta-analysis to review 55 evaluations of the effects of mentoring programs on youth. Overall, findings provide evidence of only a modest or small benefit of program participation for the average youth. Program effects are enhanced significantly, however, when greater numbers of both theory-based and empirically based "best practices" are utilized and when strong relationships are formed between mentors and youth. Youth from backgrounds of environmental risk and disadvantage appear most likely to benefit from participation in mentoring programs. Outcomes for youth at-risk due to personal vulnerabilities have varied substantially in relation to program characteristics, with a noteworthy potential evident for poorly implemented programs to actually have an adverse effect on such youth. Recommendations include greater adherence to guidelines for the design and implementation of effective mentoring programs as well as more in-depth assessment of relationship and contextual factors in the evaluation of programs.

The moderating influence of job performance dimensions on convergence of supervisory and peer ratings of job performance: unconfounding construct-level convergence and rating difficulty

Meta-analysis was used to cumulate the correlations between supervisor and peer ratings for different dimensions of job performance. The general pattern in the data suggested that raters from the same organizational level disagree as much as raters from different levels. Methods were used to separate the effects of rating difficulty and lack of construct-level convergence on the correlation between supervisor and peer ratings. The authors found complete construct-level convergence for ratings of overall job performance, productivity, effort, job knowledge, quality, and leadership but not for ratings of administrative competence, interpersonal competence, and compliance or acceptance of authority. Higher rating difficulty was more strongly associated with lower mean observed peer-supervisor correlations than were construct-level disagreements between peers and supervisors. Implications for research and practice are discussed.

Preserving the ethical propriety of statistical devices

C. D. Herrera (1996) introduced an innovative argument against the use of deception in psychological research. In essence, Herrera contended that because of the presumed problems with null hypothesis statistical testing, researchers could not justify their continued use of deception in research. Although this is an interesting argument, there are several alternative perspectives that must be considered. In examining these alternatives, the author concluded that psychologists may continue to use deception under certain circumstances outlined in the American Psychological Association's ethical code of conduct.

Individual differences in latent neuropsychological abilities at addictions treatment entry

The latent structure of neuropsychological abilities and risk factors for impairment were examined in 197 persons entering addictions treatment. Confirmatory factor analysis yielded 4 factors: Executive, Memory, Verbal, and Processing Speed. The measurement model was consistent with evidence that neuropsychological test performance is factorially complex and supported by multiple brain regions. Path analyses showed that risk factors explained 34%-57% of the true variance in abilities. Age, education, and medical status had the most generalized and robust associations with abilities. Drug use disorder diagnoses, childhood behavior problems, familial alcoholism, and psychopathology were also significantly related to specific latent abilities. Knowledge of neuropsychological impairment may be clinically useful, and selected risk factors may help treatment providers decide which clients should receive formal neuropsychological assessment.

Psychometric evaluation of a Swedish version of the Reiss Screen for Maladaptive Behavior

BACKGROUND

People with intellectual disability (ID) are afflicted by mental health problems to a greater extent than other individuals, and the coexistence of ID and mental health problems involves diagnostic as well as treatment difficulties.

METHODS

A Swedish version of the Reiss Screen for Maladaptive Behavior (RSMB), an instrument used for identification of mental health problems in people with intellectual disability (ID) was evaluated in terms of inter-rater agreement, internal consistency, item grouping and criterion validity based on a random sample and a clinical group of adults with ID.

RESULTS

The Swedish version of the RSMB had moderate-to-low inter-rater agreement on specific items and good internal consistency. The total score was considered to be a fairly reliable measure of a positive or negative result on the RSMB. A principal component analysis yielded seven interpretable components. A close resemblance in sets of items between the Swedish version and the original version of RSMB was found for three subscales: Aggressive Behaviour, Avoidance Disorder and Depression (Behavioural Signs). The outcome of the criterion validity analysis indicated a higher rate of false negatives than false positives.

CONCLUSIONS

The potential influence of concurrent psychopharmacological treatment is discussed. It is concluded that the Swedish version of the RSMB can be used as intended by staff as a primary screening device for the identification of mental health problems among people with ID in a Swedish setting.

Combining effect size estimates in meta-analysis with repeated measures and independent-groups designs

When a meta-analysis on results from experimental studies is conducted, differences in the study design must be taken into consideration. A method for combining results across independent-groups and repeated measures designs is described, and the conditions under which such an analysis is appropriate are discussed. Combining results across designs requires that (a) all effect sizes be transformed into a common metric, (b) effect sizes from each design estimate the same treatment effect, and (c) meta-analysis procedures use design-specific estimates of sampling variance to reflect the precision of the effect size estimates.

Confirmatory factor analysis of single- and multiple-factor competing models of the dissociative experiences scale in a nonclinical sample

Previous research on the Dissociative Experiences Scale (DES) has demonstrated that (a) dissociation is quantifiable in both clinical and nonclinical samples and (b) a three-factor structure (amnesia, depersonalization, and absorption) is tenable for clinical samples. The factor structurefor nonclinical samples is less clear, with one- and multiple-factor solutions proposed. To clarify the DESfactor structure in nonclinical samples, confirmatory factor analyses were conducted on (a) one-, two-, three-, and four-factorfirst-order models and (b) two bifactor (hierarchical) models of DES scoresfor two samples of nonclinical university students. Results of delta(chi2) and goodness-of-fit indices support the three-factor (first-order) model as bestfitting of the datafor these samples. The utility of this DES model for screening both dissociative pathology and elevated normal dissociative behavior in clinical and nonclinical populations is discussed.

Methodological characteristics and quality of alcohol treatment outcome studies, 1970-98: an expanded evaluation

AIMS

To examine the methodological quality of the research literature examining treatment for alcohol use disorders.

DESIGN

In total, 701 studies first reported between 1970 and 1998 were evaluated with a scoring system covering 19 areas of research quality.

FINDINGS

Methodological quality improved from a score of 8.2 out of a possible 28.5 in the 1970s, to 10.6 in the 1990s. Strengths included reporting the initial number of participants and conducting follow-ups of 12 months or longer. Although the percentage of studies with adequate power also increased overall, the average statistical power of comparative studies to detect a medium-sized treatment effect was low (0.54).

CONCLUSIONS

Areas with room for improvement include: ensuring that follow-up data are collected when respondents are not under the influence of alcohol, testing for differential dropout among treatment groups with respect to participant background characteristics, reporting the number of individuals being treated in the programs from which samples are drawn, noting the reliability and validity of measures used and conducting process analyses to examine potential mechanisms underlying treatment effects.

When paying attention becomes counterproductive: impact of divided versus skill-focused attention on novice and experienced performance of sensorimotor skills

Two experiments examined the impact of attention on sensorimotor skills. In Experiment 1, experienced golfers putted under dual-task conditions designed to distract attention from putting and under skill-focused conditions that prompted attention to step-by-step putting performance. Dual-task condition putting was more accurate. In Experiment 2, right-footed novice and experienced soccer players dribbled through a slalom course under dual-task or skill-focused conditions. When using their dominant right foot, experts again performed better in the dual-task condition. However, when using their less proficient left foot, experts performed better in the skill-focused condition. Novices performed better under skill-focus regardless of foot. Whereas novices and the less-proficient performances of experts benefit from online attentional monitoring of step-by-step performance, high-level skill execution is harmed.

Measures of self-efficacy and optimism in older adults with generalized anxiety

This study provides initial psychometric data for the Self-Efficacy Scale (SES) and the Life Orientation Test (LOT) in a sample of older adults with generalized anxiety disorder (GAD). Participants included 76 adults, ages 60 to 80, who met Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria for GAD. Self-efficacy and outcome expectancies were lower in older adults with GAD relative to published data from younger and older community samples. Both the SES and LOT demonstrated adequate internal consistency. Confirmatory factor analysis provided evidence for optimism and pessimism factors within the LOT and exploratory factor analysis of the SES suggested threefactors that overlap with previous findings. Overall, the data support the potential utility of these instruments in late-life GAD and set the stage forfuture investigations of generalized self-efficacy expectancies and outcome expectancies (or optimism) as they relate to the prediction of affect and behavior in this group.

Brief interventions for alcohol problems: a meta-analytic review of controlled investigations in treatment-seeking and non-treatment-seeking populations

Brief interventions for alcohol use disorders have been the focus of considerable research. In this meta-analytic review, we considered studies comparing brief interventions with either control or extended treatment conditions. We calculated the effect sizes for multiple drinking-related outcomes at multiple follow-up points, and took into account the critical distinction between treatment-seeking and non-treatment-seeking samples. Most investigations fell into one of two types: those comparing brief interventions with control conditions in non-treatment-seeking samples (n = 34) and those comparing brief interventions with extended treatment in treatment-seeking samples (n = 20). For studies of the first type, small to medium aggregate effect sizes in favor of brief interventions emerged across different follow-up points. At follow-up after > 3-6 months, the effect for brief interventions compared to control conditions was significantly larger when individuals with more severe alcohol problems were excluded. For studies of the second type, the effect sizes were largely not significantly different from zero. This review summarizes additional positive evidence for brief interventions compared to control conditions typically delivered by health-care professionals to non-treatment-seeking samples. The results concur with previous reviews that found little difference between brief and extended treatment conditions. Because the evidence regarding brief interventions comes from different types of investigation with different samples, generalizations should be restricted to the populations, treatment characteristics and contexts represented in those studies.

A structure-based approach to psychological assessment: matching measurement models to latent structure

The present article sets forth the argument that psychological assessment should be based on a construct's latent structure. The authors differentiate dimensional (continuous) and taxonic (categorical) structures at the latentand manifest levels and describe the advantages of matching the assessment approach to the latent structure of a construct. A proper match will decrease measurement error, increase statistical power, clarify statistical relationships, and facilitate the location of an efficient cutting score when applicable. Thus, individuals will be placed along a continuum or assigned to classes more accurately. The authors briefly review the methods by which latent structure can be determined and outline a structure-based approach to assessment that builds on dimensional scaling models, such as item response theory, while incorporating classification methods as appropriate. Finally, the authors empirically demonstrate the utility of their approach and discuss its compatibility with traditional assessment methods and with computerized adaptive testing.

Mediators of age-related differences in recollective experience in recognition memory

This study examined states of awareness with the Remember/Know paradigm during verbal recognition memory in young and old adults. Following the presentation of a word list, subjects undertook a recognition test and indicated whether they could consciously recollect its prior occurrence (R) or recognize it on some other basis, without conscious recollection (K). In this individual-difference approach we also incorporated various processing-speed and working-memory measures to study the link between aging, states of awareness and processing resources. The results revealed that, compared to younger adults, older adults exhibited a decline in the amount of R responses during the recognition test whereas the amount of K responses did not change. Structural equation modeling indicated that a slower processing speed associated with a limited working-memory capacity is a key to explaining age-related variance in conscious recollection. The findings offer further support for the distinction between remembering and knowing and for the processing-resources hypothesis of aging.

Differential item functioning in a Spanish translation of the PTSD checklist: detection and evaluation of impact

This study demonstrated the application of an innovative item response theory (IRT) based approach to evaluating measurement equivalence, comparing a newly developed Spanish version of the Posttraumatic Stress Disorder Checklist-Civilian Version (PCL-C) with the established English version. Basic principles and practical issues faced in the application of IRT methods for instrument evaluation are discussed. Data were derived from a study of the mental health consequences of community violence in both Spanish speakers (n = 102) and English speakers (n = 284). Results of differential item functioning (DIF) analyses revealed that the 2 versions were not fully equivalent on an item-by-item basis in that 6 of the 17 items displayed uniform DIF. No bias was observed, however, at the composite PCL-C scale score, indicating that the 2 language versions can be combined for scale-level analyses.

The reliability and validity of the psychopathy checklist: youth version (PCL:YV) in nonincarcerated adolescent males

Current knowledge about the validity of the psychopathy syndrome in youth is limited largely to studies relying on parent-teacher rating scales or slight modifications of adult measures. Recently, the Psychopathy Checklist: Youth Version (PCL:YV) was designed for use with adolescents. However, most studies that have used this measure examined incarcerated males and addressed only validity criteria related to antisocial behavior. We investigated the generality and construct validity of the psychopathy syndrome in an adolescent sample by assessing 115 adolescent males on probation with the PCL:YV. Reliability of measurement was high. PCL:YV ratings predicted not only antisocial behaviour but also other indices of childhood psychopathology, interpersonal behaviors associated with adult psychopathy, and a lack of attachment to parents. These findings suggest that the PCL:YV identifies a syndrome in adolescence consistent with theory and research on adult males.

Revisiting field experimentation: field notes for the future

Field experiments in the social sciences were increasingly used in the 20th century. This article briefly reviews some important lessons in design, analysis, and theory of field experiments emerging from that experience. Topics include the importance of ensuring that selection into experiments and assignment to conditions occurs properly, how to prevent and analyze attrition, the need to attend to power and effect size, how to measure and take partial treatment implementation into account in analyses, modern analyses of quasi-experimental and multilevel data, Rubin's model, and the role of internal and external validity. The article ends with observations on the computer revolution in methodology and statistics, convergences in theory and methods across disciplines, the need for an empirical program of methodological research, the key problem of selection bias, and the inevitability of increased specialization in field experimentation in the years to come.

Principles and practice in reporting structural equation analyses

Principles for reporting analyses using structural equation modeling are reviewed, with the goal of supplying readers with complete and accurate information. It is recommended that every report give a detailed justification of the model used, along with plausible alternatives and an account of identifiability. Nonnormality and missing data problems should also be addressed. A complete set of parameters and their standard errors is desirable, and it will often be convenient to supply the correlation matrix and discrepancies, as well as goodness-of-fit indices, so that readers can exercise independent critical judgment. A survey of fairly representative studies compares recent practice with the principles of reporting recommended here.