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PubMedDate not supplied

Quality of life in cardiac patient research: a meta-analysis.

This article reports a meta-analysis of 84 studies of quality of life (QOL) in cardiac patient populations published in the 5-year period 1987-1991. Selected methodologies and substantive characteristics of the studies are described. An overall effect size of .31 indicated a small but significant positive effect of pharmacologic, mechanical, surgical, nursing, or other treatment on QOL. No negative effect of treatment was found for any cardiovascular diagnostic category. Homogeneity analysis revealed eight potential moderators of the overall effect size: quality of study, gender of sample, time dimension, sampling method, intervention, marital status of subjects, quality-of-life dimension measured, and sample size.

Aged↗
PubMedDate not supplied

Effects of distraction on children's pain and distress during medical procedures: a meta-analysis.

BACKGROUND: It is difficult to determine the usefulness of distraction to decrease children's distress behavior and pain during medical procedures because many studies use very small samples and report inconsistent findings. OBJECTIVES: To investigate the mean effect sizes across studies for the effects of distraction on young children's distress behavior and self-reported pain during medical procedures. METHOD: Hunter and Schmidt's (1990) procedures were used to analyze 16 studies (total n = 491) on children's distress behavior and 10 studies (total n = 535) on children's pain. RESULTS: For distress behavior, the mean effect size was 0.33 (+/-0.17), with 74% of the variance accounted for by sampling and measurement error. For pain, the mean effect size was 0.62 (+/-0.42) with 35% of the variance accounted for. Analysis of studies on pain that limited the sample to children 7 years of age or younger (total n = 286) increased the amount of explained variance to 60%. CONCLUSIONS: Distraction had a positive effect on children's distress behavior across the populations represented in this study. The effect of distraction on children's self-reported pain is influenced by moderator variables. Controlling for age and type of painful procedure significantly increased the amount of explained variance, but there are other unidentified moderators at work.

Adolescent↗
PubMedDate not supplied

Predictors of postpartum depression: an update.

BACKGROUND: Approximately 13% of women experience postpartum depression. Early recognition is one of the most difficult challenges with this mood disorder because of how covertly it is suffered. OBJECTIVES: The purpose of this meta-analysis was to update the findings of an earlier meta-analysis of postpartum depression predictors that had synthesized the results of studies conducted mostly in the 1980s. METHOD: A meta-analysis of 84 studies published in the decade of the 1990s was conducted to determine the magnitude of the relationships between postpartum depression and various risk factors. Using the software system Advanced Basic Meta-Analysis, effect sizes were calculated three ways: unweighted, weighted by sample size, and weighted by quality index score. RESULTS: Thirteen significant predictors of postpartum depression were revealed. Ten of the 13 risk factors had moderate effect sizes while three predictors had small effect sizes. The mean effect size indicator ranges for each risk factor were as follows: prenatal depression (.44 to .46), self esteem (.45 to. 47), childcare stress (.45 to .46), prenatal anxiety (.41 to .45), life stress (.38 to .40), social support (.36 to .41), marital relationship (.38 to .39), history of previous depression (.38 to .39), infant temperament (.33 to .34), maternity blues (.25 to .31), marital status (.21 to .35), socioeconomic status (.19 to .22), and unplanned/unwanted pregnancy (.14 to .17). CONCLUSIONS: Results confirmed findings of an earlier meta-analysis and in addition revealed four new predictors of postpartum depression: self-esteem, marital status, socioeconomic status, and unplanned/unwanted pregnancy.

Anxiety↗
PubMedDate not supplied

Reducing venipuncture and intravenous insertion pain with eutectic mixture of local anesthetic: a meta-analysis.

BACKGROUND: The eutectic mixture of local anesthetics (EMLA), by producing dermal anesthesia through contact with intact skin, has become a major indication for the reduction of pain experienced during venipuncture (VE) and intravenous (IV) insertion. OBJECTIVES: The purpose of the study was to determine the mean effect sizes and moderators of EMLA cream application in reducing VE and IV insertion pain. METHOD: A meta-analysis of 20 studies was conducted to determine the magnitude of the effect of EMLA cream on VE and IV insertion pain. Effect sizes were calculated three ways: weighted, unweighted, and weighted by quality index score. Potential moderating variables of sample age, premedication, therapist control, insertion site, application duration, research design, pain scale, and funding, were investigated for their influence on EMLA's effect. RESULTS: EMLA cream had a large significant effect on VE pain (d = 1.05) with a 95% confidence interval from.92 to 1.34 and a large significant effect on IV insertion pain (d = 1.04) with a 95% confidence interval from.84 to 1.46. Subject age (child versus adult), type of pain scale, number of therapists, location of insertion site, premedication, funding, or study design did not appear to act as effect modifiers. CONCLUSIONS: EMLA cream can significantly decrease VE and IV insertion pain in 85% of the population.

Anesthetics, Combined↗
PubMedDate not supplied

SPSS and SAS programming for the testing of mediation models.

BACKGROUND: Mediation modeling can explain the nature of the relation among three or more variables. In addition, it can be used to show how a variable mediates the relation between levels of intervention and outcome. The Sobel test, developed in 1990, provides a statistical method for determining the influence of a mediator on an intervention or outcome. Although interactive Web-based and stand-alone methods exist for computing the Sobel test, SPSS and SAS programs that automatically run the required regression analyses and computations increase the accessibility of mediation modeling to nursing researchers. OBJECTIVES: To illustrate the utility of the Sobel test and to make this programming available to the Nursing Research audience in both SAS and SPSS. METHODS: The history, logic, and technical aspects of mediation testing are introduced. The syntax files sobel.sps and sobel.sas, created to automate the computation of the regression analysis and test statistic, are available from the corresponding author. RESULTS: The reported programming allows the user to complete mediation testing with the user's own data in a single-step fashion. A technical manual included with the programming provides instruction on program use and interpretation of the output. CONCLUSION: Mediation modeling is a useful tool for describing the relation between three or more variables. Programming and manuals for using this model are made available.

Data Interpretation, Statistical↗
PubMedDate not supplied

A meta-analysis of the effect of hospital-based case management on hospital length-of-stay and readmission.

BACKGROUND: Although many hospital-based case management (CM) interventions have been studied, there is little work summarizing the effectiveness of these studies. OBJECTIVES: The purpose of this study was to investigate the effect of hospital-based CM compared with usual care on length of hospital stay and readmission rate. METHOD: A meta-analytic method was employed to analyze the effect sizes of CM intervention on outcomes. Eligible studies were retrieved using computerized database searches, footnote chasing, and contact with content experts. The authors reviewed the final 12 studies, and the effect size, 95% confidence interval (CI), sensitivity, homogeneity, and publication bias were analyzed. RESULTS: The overall average weighted effect size on length of stay (LOS) was 0.094 with a 95% CI of -0.032 to 0.220. The overall odds ratio for readmission was 0.87 with a 95% CI of 0.69 to 1.04. Overall, hospital-based CM interventions were not significantly effective in reducing LOS and readmissions. However, CM for patients with heart failure (effect size of 0.241 with a 95% CI of 0.012 to 0.470) was significantly effective in reducing LOS, although it was not effective for stroke patients (effect size of -0.226 with a 95% CI of -0.542 to 0.089) and frail elders (effect size of 0.126 with a 95% CI of -0.073 to 0.324). Analysis indicated that in this meta-analysis publication bias was unlikely. DISCUSSION: The findings of this meta-analysis demonstrate a 6% decrease in readmission rate for patients who received hospital-based CM interventions. Further meta-analytic studies are needed to investigate the effectiveness of CM on other outcomes.

Aged↗
PubMedDate not supplied

Do internal standards of quality of life change in lung cancer patients?

BACKGROUND: Measurement of health-related quality of life (QOL) over time often yields results that may be difficult to understand. Patients may change their internal standards of QOL as a result of adaptation to deteriorating health, a phenomenon referred to as response shift. OBJECTIVES: To examine changes in internal standards of fatigue, global health/QOL, and physical function in patients with inoperable lung cancer at 3 months (n = 115) and 6 months (n = 89) after a baseline measurement close to diagnosis. Significant changes were expected to occur only in patients who reported improvement or deterioration in fatigue and global health/QOL. METHODS: Fatigue, global health/QOL, and physical function were assessed with the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ-C30, version 3.0). At follow-up, this questionnaire was administered conventionally and as a retrospective baseline assessment (thentest). Subjective transition questions were used to form mutually exclusive patient subgroups (i.e., deterioration, stable, or improvement). RESULTS: With respect to fatigue, significant changes occurred in patients reporting deterioration at 3 months follow-up and in patients reporting improvement after 6 months, but not in patients reporting improvement after 3 months or deterioration after 6 months. Significant changes in global health/QOL were found in patients reporting improvement at both 3 and 6 months follow-up and unexpectedly in stable patients after 3 months. No significant changes were found in patients reporting deteriorated global health/QOL at 3 and 6 months. Unexpectedly, changes occurred at both 3 and 6 months in patients reporting improved physical function. DISCUSSION: Given these mixed findings, it cannot be concluded that changes in internal standards occurred. These severely ill patients reported high levels of symptoms at baseline and may in part have adapted to their symptoms before study entry.

Activities of Daily Living↗
PubMed1996

An observational asthma study alters emergency department use: the Hawthorne effect.

The objective of this study was to document that an observational study decreases the use of the emergency department (ED) for asthma. Comparison of rates between an audit and prospective period were used at a regional referral pediatric hospital ED. A total of 526 asthma visits from February 12, 1992, to April 10, 1992, were examined in an initial audit and compared to 725 visits during a prospective study from May 16, 1993, to September 29, 1993. A physician check list for medications and follow-up plans was utilized during the prospective study. The rate of repeat visits and admissions was compared between the audit and the prospective periods. In the audit, 422 asthma patients were seen, and there were 68 repeat visits within one week of the initial visit and 153 admissions. For 29 of the 68 repeat visits there was no documentation that medication had been increased after the initial visit. No follow-up plans were recorded in 275 of the 526 visits. During the prospective period 668 children presented to the ED with asthma, and 346 were enrolled into the study on risks for repeat visits. There were 57 repeat visits and 89 admissions. The repeat visit rate during the prospective period was 9 and 8%, respectively, in the enrolled and nonenrolled subjects. The repeat visit and admission rate decreased during the prospective period as compared to during the audit by 39% (P = 0.004) and 58% (P < 0.0001), respectively. A possible explanation for the difference in admission and repeat visit rates between the audit and prospective study is that physicians' behavior may have been altered by the awareness that their behavior was being closely monitored during the study.

Asthma↗
PubMed2000

Predictors of female condom use among women exchanging street sex in New York City.

BACKGROUND: Alternative female-initiated barrier methods, such as the female condom, are needed among women exchanging street sex to enhance their ability to protect themselves from HIV and STD infection. OBJECTIVE: To describe predictors of female condom use among 96 women exchanging sex for money and drugs on the streets of New York City. STUDY DESIGN: A total of 113 sex workers received a baseline interview, a demonstration on proper female condom use, and 10 female condoms. A total of 101 sex workers received a followed-up evaluation at 2 weeks, of which 96 were included in data analysis. Predictors of condom use were analyzed for (1) any type of use; and (2) use with commercial partners. RESULTS: The strongest predictors of female condom use among this sample of sex workers were (1) living with someone with a drug or alcohol problem; (2) having heard of the female condom; and (3) homelessness. Current physical or sexual abuse by a commercial partner and marriage decreased the probability of female condom use. CONCLUSIONS: Female condom distribution encouraged sex workers who may be most vulnerable or who reported characteristics or behaviors associated with the highest sexually transmitted disease and HIV risk to try female condoms with commercial partners. Implications for intervention development include the need to develop innovative programs provided on the street (e.g., through peers) that can access homeless, drug-using sex workers in the most at-risk environments.

Adult↗
PubMedDate not supplied

An integrative review of computer-based simulation in the education process.

The purpose of this study was to review quantitative studies related to computer-based simulation and healthcare education and determine the effect of simulation on education and learning. A total of 513 references were retrieved, but only 9 quantitative studies met the inclusion criteria. To synthesize the data, the mean scores and standard deviations of the studies were used to determine the effect size, the index, and the direction of the effect. This review indicates that 75% of the studies showed positive effects of simulation on skill and/or knowledge acquisition. The potential of computer-based simulation as an education augmentation is enormous, but research is needed to determine effective and successful uses of high-fidelity simulations for nursing education.

Clinical Competence↗
PubMed1998

Screening for drug related dyspepsia: an analysis of prescription symmetry.

OBJECTIVE: Most patients with severe upper dyspepsia are treated empirically with ulcer drugs. Drug-induced dyspepsia might therefore be reflected in the sequencing of ulcer drugs relative to other medications. Our aim was to screen a large population-base prescription database for evidence of drug-induced dyspepsia. METHODS: Prescription data on 31,232 incident users of ulcer drugs were drawn from a research database, covering the county of Funen, Denmark. We identified all individuals who had started their first recorded therapies with an ulcer drug and another non-ulcer drug within a 100 day span. In this selected group, there would normally be an equal number starting either drug first, while a dyspepsia-provoking effect of the non-ulcer drug would manifest as an excess of individuals with the ulcer drug prescribed last. This screening method is robust to confounders that are stable over time. RESULTS: Only non-steroidal antiinflammatory drugs (adjusted rate ratio (RR) 1.8, 95% confidence interval (CI), 1.6-2.0), calcium blockers (RR 1.4, CI 1.2-1.7), corticosteroids (RR 1.1, CI 1.0-1.3), angiotensin converting enzyme inhibitors (RR 1.4, CI 1.1-1.7) and methylxanthines (RR 1.5, CI 1.1-2.2) showed a significant asymmetry suggesting a dyspepsia-provoking effect. An analysis of effect modifiers suggested that the signals for corticosteroids and for angiotensin converting enzyme inhibitors were explained by concurrent use of non-steroidal anti-inflammatory drugs and by underlying congestive heart failure. The signal for non-steroidal anti-inflammatory drugs may be explained by the known reputation of non-steroidal antiinflammatory drugs for causing ulcers. CONCLUSION: There are hardly any important unknown drug effects that mimic acid related dyspepsia. Drug-induced dyspepsia contributes little to the overall use of ulcer drugs.

Aged↗
PubMed2004

Do subject characteristics modify the effects of particulate air pollution on daily mortality among the elderly?

OBJECTIVE: Studies have reported associations between mortality and air pollution, but questions subsist on the identification of susceptible subgroups in the population. We studied individual characteristics that modify the relationship between particulate air pollution and mortality among elderly. METHOD: We examined 527 nonaccidental deaths (197 cardiorespiratory deaths) among the 1469 subjects from the Personnes Agees QUID cohort in Bordeaux between 1988 and 1997. Air pollution was measured as black smoke by urban monitoring background stations. We used a case crossover approach and calculated odds ratio by conditional logistic regression models. RESULTS: We observed associations between the third lag day and cardiorespiratory mortality for an increase of 10 microg/m3 of black smoke (odds ratio = 1.30, 95% confidence interval: 1.01-1.68). CONCLUSIONS: Our results provide insight into factors possibly conferring susceptibility to the acute effect of urban air pollution.

Aged↗
PubMed2006

Association between arsenic exposure from drinking water and anemia during pregnancy.

OBJECTIVE: Arsenic is associated with numerous health effects. We investigated the association between arsenic exposure from drinking water and anemia during pregnancy. METHODS: We conducted a prospective cohort pregnancy study in two Chilean cities with contrasting drinking water arsenic levels: 40 microg/L versus <1 microg/L. This analysis included 810 women who gave birth to live, singleton infants and had at least one hemoglobin determination during pregnancy. RESULTS: Arsenic exposed women were more likely to be anemic during pregnancy after adjusting for other factors. Furthermore, as pregnancy progressed, the prevalence of anemia rose more sharply among those in the exposed versus unexposed city: 49% versus 17%. CONCLUSION: This study suggests an association between moderate arsenic in drinking water and anemia during pregnancy. Further research is needed to identify the specific types of anemia underlying the association.

Adolescent↗
PubMed2004

Adjusting for patient characteristics and selection effects in assessment of community mental health centers.

OBJECTIVE: The objective of this study was to determine the effect of patient socioeconomic characteristics and center selection of patients on measured performance of community mental health centers. DATA SOURCE/STUDY SETTING: Data were taken from the administrative records of Indiana's public mental health system for 16,516 adults with severe, persistent mental illness treated in 30 community mental health centers. Center performance was compared using longitudinal information on patient functioning. METHODS: A mixed random-effects model that is suitable for fitting data with a hierarchical structure was used to assess relative performance. PRINCIPAL FINDINGS: Measured performance was found to depend significantly on patient education, income, marital status, race, ethnicity, and baseline health (P<0.05). Results also indicated centers that were more successful at maintaining patients in treatment were unfairly underranked by unadjusted performance scores. CONCLUSIONS: Both the socioeconomic background of patients and patient selection by centers impact apparent performance in community mental health care. If observational data are used to evaluate community-based providers, analysts might need to account for both effects to ensure comparisons of relative performance are accurate.

Adult↗
PubMed2001

Effect size: utility and application in neuroscience nursing.

Effect size is used in single studies to complement inferential statistical analysis. It also is used to compare and synthesize data across studies in meta-analysis. Effect size provides information about clinical importance of differences found in research observations. For researchers, effect size is useful in establishing support for the theoretical framework of a story and in planning for future research. Application of effect size to data in three studies about the effects of backrest position on ICP and CPP in brain-injured adults illustrates the utility of effect size analysis in neuroscience nursing research.

Bed Rest↗
PubMed2000

Contrasts and correlations in effect-size estimation.

This article describes procedures for presenting standardized measures of effect size when contrasts are used to ask focused questions of data. The simplest contrasts consist of comparisons of two samples (e.g., based on the independent t statistic). Useful effect-size indices in this situation are members of the g family (e.g., Hedges's g and Cohen's d) and the Pearson r. We review expressions for calculating these measures and for transforming them back and forth, and describe how to adjust formulas for obtaining g or d from t, or r from g, when the sample sizes are unequal. The real-life implications of d or g calculated from t become problematic when there are more than two groups, but the correlational approach is adaptable and interpretable, although more complex than in the case of two groups. We describe a family of four conceptually related correlation indices: the alerting correlation, the contrast correlation, the effect-size correlation, and the BESD (binomial effect-size display) correlation. These last three correlations are identical in the simple setting of only two groups, but differ when there are more than two groups.

Analysis of Variance↗
PubMed2002

An observational study of antibiotic prescribing behavior and the Hawthorne effect.

OBJECTIVES: To assess whether prospective, observational study procedures, including questionnaires and audio recording, are associated with different patterns of physician diagnostic decision making and antibiotic prescribing. DATA SOURCES/SETTING: (1) Survey data from a prospective observational study of treatment patterns for children with acute upper respiratory illnesses (10/96-3/97) and (2) retrospective medical record abstraction data of nonobserved encounters for the same problems occurring during (10/96-3/97) and one year after (10/97-3/98) the observational study period. Ten pediatricians in two community practices were studied. STUDY DESIGN: Patterns of diagnoses recorded in the medical record and antibiotics ordered for visits occurring outside of the observational study (same time period and one year later) were compared with the pattern of diagnoses and antibiotics ordered during the observational study. DATA COLLECTION/EXTRACTION METHODS: For the observational study (10/96-2/97), diagnosis and treatment choices were obtained from questionnaires completed by physicians immediately following the visit. For the nonstudy encounters (10/96-3/97 and 10/97-3/98), data were abstracted from medical records one year after the observational study was completed. PRINCIPAL FINDINGS: The proportion of viral cases in which an antibiotic was prescribed was 29 percentage points lower for the observational study compared to the retrospective analysis (p < .05). In one of two study sites, the proportion of cases assigned a bacterial diagnosis was 29 percentage points lower in the observational study period compared to the retrospective study (p <.05). CONCLUSIONS: Observational study procedures including questionnaires and audio recording can affect antibiotic prescribing behavior. Future observational studies aimed at examining the frequency of inappropriate antibiotic prescribing should measure and adjust for the Hawthorne effect; without such adjustments, the results will likely underestimate the true degree of the problem. Future interventions aimed at decreasing inappropriate antibiotic prescribing should consider "harnessing" the Hawthorne effect through performance feedback to participating physicians.

Anti-Bacterial Agents↗