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PubMed1994

Adolescent depression: children's depression inventory norms, suicidal ideation, and (weak) gender effects.

Normative data for the Children's Depression Inventory on 792 nonreferred students in Grades 7 through 12 were gathered. It was found that girls endorsed more depressive symptomatology than did boys at statistically significant levels, but the magnitude of the effect was trivial. More than one-third of the overall sample reported suicidal ideation. Although a significant gender effect was obtained, again the effect was weak in magnitude. It is suggested that effect-size analyses may advance understanding of normative research on depression.

Adolescent↗
PubMed1994

A meta-analysis of intervention effectiveness for symptom management in oncology nursing research.

PURPOSE: To describe intervention effectiveness for symptom management in oncology nursing research. DESIGN: Integrative research review and meta-analysis. SAMPLE: 28 randomized experimental and control group studies of symptom management that were identified from 428 published and unpublished oncology nursing research reports authored by nurses from 1981-1990. METHODS: Experimental studies identified and coded by four oncology nurse specialists; findings transformed into effect sizes; effect sizes combined into overall effect for 28 studies; and effects clustered by symptoms, interventions, and outcomes. MAIN OUTCOME MEASURE: Combined effect for 28 symptom management study outcomes. FINDINGS: For 28 study outcomes tested for symptom management, weighted average effect was d = 0.47, the 95% confidence interval ranged from 0.31 to 0.61, statistical significance was p = 5.17 x 10(-12) with wide variability of effect (chi 2 = 66.574, df = 27, p = 3.41 x 10(-5), and success rate improved from 39% to 62% for subjects in the treatment group. CONCLUSION: Interventions were effective in relieving symptoms in the collection of studies and in the clusters for managing nausea and vomiting, pain, anxiety, alopecia, infection, and side effects of chemotherapy. IMPLICATIONS FOR NURSING PRACTICE: Missing data related to subject characteristics and need for replications prior to use in practice preclude making specific recommendations at this time for research-based nursing interventions for symptom management in patients with cancer.

Clinical Nursing Research↗
PubMedDate not supplied

Experience with poliovaccines in the control of poliomyelitis in India.

OPV was introduced in the National Immunisation Programme (NIP) in 1979. The reported number of cases of poliomyelitis was about 20,000 in 1979, 38,000 in 1981; it gradually declined to the pre-immunisation level of 20,000 in 1986, but increased to 28,000 in 1987. In 1989, 10 years after NIP, the reported number of cases fell below the pre-immunisation level, and has further declined to 5669 in 1991. The 3-dose OPV coverage during infancy was estimated to be about 80% in 1991. If reporting efficiency is 10%, then about 60,000 cases would have occurred in 1991, for an incidence of disease of about 7/100,000 in the total population of 840 million. Three questions arise: (1) Why did it take over 10 years of NIP to reduce the disease burden? (2) Why is the disease occurring at a high incidence level in spite of 80% immunisation coverage? (3) Will we be able to eliminate poliomyelitis and eradicate polioviruses by the year 2000 by sustaining the high immunisation coverage using 3 doses of OPV? In most countries, the incidence of disease has declined immediately after instituting NIP including OPV. The vaccine efficacy (VE) of 3 doses of OPV in India is 70-93%. Hence the lack of decline of incidence during 10 years of NIP was most probably because sufficient proportions of infants were not being immunised. The incidence remains high because the VE and herd effect of 3 doses of OPV are insufficient. Vaccine failure cases will account for 2-9 cases per 100,000 per year since pre-immunisation incidence was 30 and VE is 70-93%.(ABSTRACT TRUNCATED AT 250 WORDS)

Developing Countries↗
PubMed1994

Modifiable risk factors for incident heart failure in the coronary artery surgery study.

BACKGROUND: Even with aggressive treatment, heart failure is associated with a substantial morbidity and mortality. This poor prognosis has led to increasing interest in primary prevention, and the identification of modifiable risk factors. Our objective was to determine whether modifiable cardiovascular risk factors, including systolic and diastolic blood pressure, fasting glucose level, cholesterol level, weight, and smoking, were independent risk factors for heart failure in patients with anatomically confirmed coronary artery disease. METHODS: We studied all patients with documented coronary artery disease eligible for the multicenter, randomized-controlled Coronary Artery Surgery Study. After excluding 79 prevalent cases, we identified incident cases of heart failure using hospital discharge abstracts, mortality records, or self-reported follow-up questionnaires. Criteria for self-reported cases were treatment with digitalis and/or furosemide plus two or more heart failure symptoms, including dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, or edema. Cox regression analysis was used to estimate adjusted relative risks. RESULTS: At 12-year follow-up, the cumulative incidence of heart failure was 20.6%. Smoking (relative risk, 1.47) and weight (relative risk, 1.15/10 kg) were independently associated with incident heart failure. Myocardial infarction during follow-up, age, female sex, and baseline left ventricular dysfunction were also risk factors for heart failure. CONCLUSIONS: Patients with stable coronary artery disease are at high risk for developing heart failure, especially following myocardial infarction. However, interventions aimed at smoking cessation and weight reduction may prevent clinical heart failure in these patients.

Coronary Disease↗
PubMed1993

Chemical plaque control: how do you advise your patients?

Certain antiplaque and antigingivitis agents have proven efficacious in the control of plaque and gingivitis. To adequately assess the magnitude of the effect that is to be expected in clinical practice, the dentist must take into account the experimental design in order to extrapolate the results of the clinical trial to the target patient population. This paper reviews the strengths and weaknesses of major clinical trial designs in light of their relationship to the results dentists can expect in clinical practice.

Anti-Infective Agents, Local↗
PubMed1993

The indirect patient care effect of a unit-based clinical nurse specialist on preventable pulmonary complications.

PURPOSE: To examine the indirect effect of a unit-based expert nurse on the incidence of preventable pulmonary complications, which were defined as malpositioned endotracheal tube and inadvertent extubation. DESIGN: A nonequivalent control group/separate samples pretest/posttest design was used to test differences in the incidence of preventable pulmonary complications before and after a 6-month intervention by a unit-based expert nurse in the experimental unit. Retrospective medical record audits were used to collect data on all consecutive admissions to the experimental and control units in March and April of years 1 and 2. RESULTS: Estimated risk ratios demonstrated a significant reduction in preventable pulmonary complications in the experimental unit after the test, even though the acuity was significantly higher in posttest patients. It was concluded that indirect patient care by a unit-based clinical nurse specialist can reduce the incidence of preventable pulmonary complications.

Adolescent↗
PubMedDate not supplied

Reconciling cross-sectional with longitudinal observations on annual decline.

In summary, numerous factors may contribute to observed differences between longitudinally and cross-sectionally derived measures of annual decline in lung function. The direction and magnitude of these differences appear hard to predict. Furthermore, although these differences can be minimized by careful modeling of the data, they cannot, in general, be completely avoided. It seems plausible, however, that both types of studies should give similar qualitative comparisons of risk factor effects if appropriately modeled. Longitudinal studies are likely to provide the most accurate and reliable estimates of lung function decline for both individuals and populations. Such data may be especially useful in identifying individuals with accelerated declines in lung function but who still have "normal" lung function as measured cross-sectionally. However, such studies require careful attention to quality control and typically require at least 4 years of follow-up before the noise in the data settles down. Multiple measurements, preferably four or more, are also necessary to reliably detect and adjust for survey effects. Cross-sectional studies, on the other hand, are simpler, cheaper, and quicker to conduct than are longitudinal studies. They may be particularly useful as a screening tool for identifying potentially affected or high-risk subjects (e.g., those with low levels of lung function) who may require further medical follow-up and/or ongoing monitoring. Both types of studies have a role in population-based occupational health hazard assessments.

Bias↗
PubMedDate not supplied

Long-term trends in United States highway emissions, ambient concentrations, and in-vehicle exposure to carbon monoxide in traffic.

This paper reviews 16 published studies conducted between 1965 and 1992 of in-vehicle exposure to carbon monoxide (CO) in traffic on urban roadways in the United States. Analysis of these studies shows a downward trend in CO exposure, which corresponds to similar trends for CO in motor vehicle emission factors and ambient concentrations. The analysis demonstrates that emission controls on motor vehicles sold in the United States have been very effective in reducing commuter CO exposure. It is recommended that future studies of this kind be done routinely in cities nationwide to provide a more robust database for accurate estimates of commuter exposure. Such studies should relate human exposure measurements to estimates of emissions at study sites to document the progress of motor vehicle emission control programs. In addition, future studies should use standard protocols to enable comparisons of results in time and space. Previous studies have shown that typical in-vehicle exposures vary by study approach (direct versus indirect), city, season, roadway type and location, travel mode, and vehicular ventilation. Future studies should carefully account for these factors.

Air Pollution, Indoor↗
PubMed1996

[The center effect in multicenter studies: fixed or random?].

The multiplication of multicentric clinical studies leads to a generalization of the use of a center effect in statistical analyses. In the simple situation where the dependent variable is quantitative and there is only a simple factor of interest, the formalisation of such a protocol corresponds to a two way ANOVA (with the factor of interest and the center factor) with generally a term of interaction. Even such a simple situation leads to interrogations, one of them being to determine whether the centre effect is fixed or random. In the first situation, the conclusion of the study will concern only the centres evaluated in the study, while in the second, the conclusion will concern the whole population from which the centers have been randomly selected. Such a generalizability has a cost: a loss of power in determining the effect of the factor of interest (the loss being as important as the interaction factor of interest x centre factor is large) and the necessity of sophisticated statistical software. This paper will focus on successively: the notion of ANOVA, of fixed or random effect (with the conceptual, formal and numerical differences that distinguish these two approaches). A numerical example is proposed.

Analysis of Variance↗
PubMed1997

The nature and extent of body-image disturbances in anorexia nervosa and bulimia nervosa: a meta-analysis.

OBJECTIVE: Although body-image disturbance is among the diagnostic criteria for anorexia nervosa and bulimia nervosa, the nature and extent of this disturbance have not been precisely identified. This is the purpose of this first meta-analysis of extant research on body image and eating disorders. METHOD: Using contemporary techniques, the meta-analysis systematically examined 66 studies (from 1974 to 1993) of perceptual and attitudinal parameters of body image among anorexics and bulimics relative to control groups. RESULTS: Attitudinal body dissatisfaction, both questionnaire and self-ideal discrepancy measures, produced substantially larger effect sizes than did perceptual size-estimation inaccuracy. Body dissatisfaction measures, whether global or weight/shape related, differentiated bulimic and anorexic groups (with bulimics having more dissatisfaction), whereas perceptual distortion indices did not. Somewhat larger effects occurred with whole-body than with body-part size-estimation assessments. Size distortion among patients with eating disorders appears unlikely to reflect a more generalized sensory/perceptual deficit. DISCUSSION: Scientific, conceptual, and clinical implications of these findings are delineated.

Anorexia Nervosa↗
PubMed1997

Theory testing, effect-size evaluation, and differential susceptibility to rearing influence: the case of mothering and attachment.

It is important to distinguish theory testing from effect-size evaluation when considering the impact of mothering on attachment security discerned in the De Wolff and van Ijzendoorn meta-analysis. Moreover, the possibility exists that this analysis both over- and underestimates mothering effects, as would be the case if infants vary in their susceptibility to rearing influence.

Child Rearing↗
PubMed1997

In search of the absent father--meta-analyses of infant-father attachment: a rejoinder to our discussants.

In our meta-analysis on sensitivity and attachment, studies on the role of the father in the development of infant attachment were excluded. In this rejoinder to our discussants, we present new meta-analytic evidence on the association between paternal sensitivity and infant-father attachment (combined effect size r[544] = .13; k = 8 studies; N = 546 families), and on the association between infant-mother and infant-father attachment (overall correlation phi = .17; k = 14 studies; N = 950). Combining the findings from several earlier meta-analyses, we present a data-based model of attachment within the family system.

Adult↗
PubMed1997

Impact of home care on hospital days: a meta analysis.

OBJECTIVE: To examine the impact of home care on hospital days. DATA SOURCES: Search of automated databases covering 1964-1994 using the key words "home care," "hospice," and "healthcare for the elderly." Home care literature review references also were inspected for additional citations. STUDY SELECTION: Of 412 articles that examined impact on hospital use/cost, those dealing with generic home care that reported hospital admissions/cost and used a comparison group receiving customary care were selected (N = 20). STUDY DESIGN: A meta-analytic analysis used secondary data sources between 1967 and 1992. DATA EXTRACTION: Study characteristics that could have an impact on effect size (i.e., country of origin, study design, disease characteristics of study sample, and length of follow-up) were abstracted and coded to serve as independent variables. Available statistics on hospital days necessary to calculate an effect size were extracted. If necessary information was missing, the authors of the articles were contacted. METHODS: Effect sizes and homogeneity of variance measures were calculated using Dstat software, weighted for sample size. Overall effect sizes were compared by the study characteristics described above. PRINCIPAL FINDINGS: Effect sizes indicate a small to moderate positive impact of home care in reducing hospital days, ranging from 2.5 to 6 days (effect sizes of -.159 and -.379, respectively), depending on the inclusion of a large quasi-experimental study with a large treatment effect. When this outlier was removed from analysis, the effect size for studies that targeted terminally ill patients exclusively was homogeneous across study subcategories; however, the effect size of studies that targeted nonterminal patients was heterogeneous, indicating that unmeasured variables or interactions account for variability. CONCLUSION: Although effect sizes were small to moderate, the consistent pattern of reduced hospital days across a majority of studies suggests for the first time that home care has a significant impact on this costly outcome.

Aged↗