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PubMedDate not supplied

Estimation by data augmentation in regression models with continuous and discrete covariates measured with error.

Estimation methods are considered for regression models which have both misclassified discrete covariates and continuous covariates measured with error. Adjusted parameter estimates are obtained using the method of data augmentation, where the true values of the covariates measured with error are regarded as missing data. Validation data on the covariates are assumed to be available. The distinction between internal and external validation data is emphasized, and its effects on the analysis are examined. The method is illustrated with simulated data.

Algorithms↗
PubMed2000

Home care by outreach nursing for chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterised by progressive airflow obstruction, worsening exercise performance and deterioration in health. It is associated with significant morbidity, mortality and costs to health care systems. Care strategies, such as outreach nursing in the community, may reduce this burden. OBJECTIVES: To evaluate the effectiveness of outreach respiratory health care worker programmes for patients with COPD in terms of improving lung function, exercise tolerance and health related quality of life (HRQL) of patient and carer, and reducing mortality and hospital service utilisation. SEARCH STRATEGY: A search was carried out using the Cochrane Airways Group database. Bibliographies of identified RCTs were searched for additional relevant RCTs. Authors of identified RCTS were contacted for other published and unpublished studies. SELECTION CRITERIA: Only randomised control trials of patients with COPD were included. The intervention was an outreach nurse visiting patients in their homes, providing support, education, monitoring patient status and providing liaison with physicians. Interventions that used nurse practitioners who provided therapeutic intervention were also included. Studies in which the therapeutic intervention under test was physical training were not included. DATA COLLECTION AND ANALYSIS: Data extraction and study quality assessment were performed independently by two reviewers. Where further or missing data was required, authors of studies were contacted. MAIN RESULTS: Four studies were found. Three assessed mortality following twelve months of care (n=96, 152 and 301), and one after seven months(n=75). Meta-analysis demonstrated that mortality was not significantly reduced by the intervention, Peto Odds Ratio 0.72; 95 % confidence interval 0.43, 1.21. Post hoc subgroup analysis suggested that mortality was reduced by the outreach nursing programme in patients with less severe disease. Significant improvements in health related quality of life were reported in one study in moderate COPD, but not in a study in patients with severe disease. No changes in lung function or exercise performance were found in the studies where data were available. Hospital admissions were reported in only one study in patients with severe disease and no benefit was observed. REVIEWER'S CONCLUSIONS: Patients with moderate COPD may have mortality and health related quality of life gains from a nursing outreach programme, but there are no data about reductions in hospital utilisation. Patients with severe COPD do not appear to have benefit from such programmes and one large study found no reduction in hospital admissions in such patients.

Community-Institutional Relations↗
PubMed2000

Long-acting beta2-agonists for chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterised by airflow limitation which is only partially reversible. Long acting beta2-agonists, effective in the management of asthma,are also recommended for COPD management so it is important to establish whether these drugs are effective in reducing COPD symptoms in view of the potential side effect and cost burden. OBJECTIVES: To determine the effectiveness of long acting beta2-adrenoceptor agonists in improving lung function and quality of life and reducing dyspnoea in patients with COPD. SEARCH STRATEGY: A search was carried out using the Cochrane Airways Group register. Bibliographies of identified RCTs were searched for additional relevant RCTs. Authors of identified RCTs were contacted for other published and unpublished studies. In addition, unpublished studies were also obtained from the pharmaceutical companies that manufacture long acting beta2- adrenoceptor agonists. SELECTION CRITERIA: All randomised controlled trials over four weeks in duration comparing treatment with long-acting beta2-adrenoceptor agonists (salmeterol and formoterol) with placebo in patients with stable non-reversible COPD. Outcome measures included forced expiratory volume in one second (FEV1), peak expiratory flow rate (PEFR), symptom scores, six minute walk distance, quality of life scores, Borg scores for dyspnoea and rescue bronchodilator use. DATA COLLECTION AND ANALYSIS: Data extraction and study quality assessment was performed independently by two reviewers. Where further or missing data were required, authors of studies were contacted. MAIN RESULTS: Thirty three abstracts were identified as potentially relevant. Of these, four randomised controlled trials (RCTs) were included in this review. Two were parallel group studies of 16 week duration and two were cross-over studies with four week treatment arms. All four RCTs assessed the efficacy of salmeterol in COPD. In a 16 week study of salmeterol 50 mcg and 100 mcg twice daily treatment, a significant increase in FEV1 was seen in both treatment groups. The weighted mean difference (WMD) for the increase in FEV1 for the 50 mcg group was 0.10 litre (95% CI: 0.05;0. 15) and in the 100 mcg group the WMD was 0.12 litre (95% CI: 0.06; 0. 17 ). In the two cross-over studies of four weeks treatment, salmeterol 50 mcg twice daily treatment did not show significant increases in FEV1 (WMD = 0.04 litre, 95% CI: -0.06; 0.15). Similarly, morning and night time PEFR was not significantly improved with salmeterol treatment. In a 16 week study, disease-specific quality of life, measured using the St. George's Respiratory Questionnaire (SGRQ), showed a significant improvement after 50 mcg twice daily, but not after 100 mcg twice daily. This improvement exceeded the threshold for a clinically significant change with this questionnaire. General health status, as measured by the Medical Outcomes Short Form 36, did not improve in any of the eight components with either salmeterol dose. No significant difference was demonstrated in the mean change from baseline in the six minute walk distance (WMD = 1.9 metres, 95% CI: -15.4;19.3). Breathlessness was reduced in one study in patients receiving salmeterol 50 mcg twice daily group. Significantly more patients in this group had Borg scores for breathlessness less than three (a score of three indicating moderate dyspnoea) compared to the placebo treated group (Peto Odds Ratio = 0.60, 95% CI: 0.40; 0.88). Neither dose of salmeterol influenced the incidence of COPD exacerbations, (50 mcg: Peto Odds Ratio = 0.74, 95% CI: 0.47, 1.15) and (100 mcg: Peto Odds Ratio = 0.98, 95% CI: 0.64, 1.52). REVIEWER'S CONCLUSIONS: Treatment of patients with COPD with long acting beta2-agonists produces only small increases in FEV1. In one study, a dose of salmeterol 50 mcg twice daily produced a reduction in breathlessness and a clinically significant improvement in quality of life. (ABSTRACT TRUNCATED)

Adrenergic beta-Agonists↗
PubMed2000

Short-acting beta 2 agonists for stable chronic obstructive pulmonary disease.

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is a chronic condition characterised by progressive airflow limitation that is at most partially reversible. Despite the lack of reversibility patients often report symptomatic improvement with short-acting beta 2 bronchodilator medications. They are used on either an "as required" or a "regular plus as required basis" and they may be used in conjunction with other bronchodilator medicines such as ipratropium and methylxanthines. These medicines are used in the management of both stable and acute exacerbations of COPD. This review examined the effect of short-acting beta 2 bronchodilators given by inhalation in stable COPD. OBJECTIVES: To determine the clinical effect and assess the adverse effects of inhaled short-acting beta 2 agonist bronchodilators compared with placebo in stable COPD. SEARCH STRATEGY: Only randomised controlled trials (RCTs) were considered. RCTs were identified using the Cochrane Airways Group database (CENTRAL). In addition, the reference lists of review articles and RCTs retrieved in full were searched for other potentially relevant citations. SELECTION CRITERIA: Only trials with adult patients with stable COPD, as defined by internationally accepted guidelines (ATS, ERS or BTS) were included in this review. All trials had a minimum duration of 7 days of regular treatment with short-acting beta 2 bronchodilators given by inhalation and compared with placebo. Data from trials where beta 2 agonists were used alone or in combination with other medicines (e.g. ipratropium bromide) were used only if there was a direct comparison between beta 2 bronchodilator alone and placebo. DATA COLLECTION AND ANALYSIS: Outcomes were analysed as continuous or dichotomous outcomes, using standard statistical techniques. For continuous outcomes, the weighted mean difference (WMD) and 95% confidence intervals were calculated and for dichotomous outcomes, the odds ratio was calculated with 95% confidence intervals by Peto's methods. Funnel plots were used to test for publication bias. MAIN RESULTS: Thirteen studies were included in this review. Most had small sample sizes and some of the sutides used very short-acting outdated compounds. All the studies used a cross-over design and were of high quality. Spirometry done at the end of study period was measured after administration of treatment (post-bronchodilator) which showed both FEV1 (0.150 L/min, 95%CI: 0. 02-0.28) and FVC (0.310 L, 95%CI: 0.00-0.62) to improve significanly but slightly when compared to placebo. A few studies measured FRC, airway resistance or conductance at the end of the study period. In all cases these measurements were done several hours after treatment, and no significant differences (p>0.05 in all cases) were found between the bronchodilator and placebo groups. Walking test Large increases in 6MW distance was observed in two studies, however one study did not show any positive improvements. There was a large increase in the 12MW distance as shown by one study. Due to the small number of studies reporting this outcome no significant differences were found in the walking distance between the bronchodilator and placebo groups. Peak Flow Rate Both morning (36. 04 L/min; 95%CI: 0.80-71.27) and evening (36.68 L/min; 95%CI: 2. 47-70.89) PEFR were significantly higher during active treatment than during placebo. Symptoms Breatlessness was measured on various scales therefore data that were presented in a suitable form were combined using standardized means for inclusion in the analysis. A significant improvement (-0.33; 95%CI: -0.58 to -0.07 with p=0.01) in the breathlessness score was observed during treatment with beta-2 agonist when compared to placebo. Cough was reported to improve significantly (data not usable) during treatment with beta2 agonist in one study but not in two others. A non-significant decrease in sputum production was reported by Wilson 1980, however four other studies reported no

Administration, Inhalation↗
PubMed1998

Correspondence analysis as a tool in fungal taxonomy.

The polyphasic approach to taxonomic problems has led to the creation of complex datasets that lend themselves to numerical analysis. The numerical study, however, has to deal with mathematical problems linked with the presence of mixed-type data originating from the investigations. Correspondence analysis (CA) is an ordination technique widely used in ecology and social sciences but only rarely applied to taxonomic problems. In CA corresponding variables and taxa ordination are obtained simultaneously, thus allowing to explore the taxonomic interrelationships between taxa and variables in a single analysis. CA can be used on large and small datasets, and can be applied to mixed-type data after appropriate coding. It is not sensitive to variation of class number and size and is useful to screen large unstructured datasets, to suggest which variables should be retained to discriminate samples, to detect outliers or erroneous data and to perform identification of unknown samples. It also has the advantage of handling missing data particularly well. On the other hand, CA is sensitive to outliers, which can cause a distortion of the geometric map of the points in the graphical display. Nevertheless, the sensitivity of correspondence analysis to outliers can be effectively used to verify data. Finally, based on symmetry of row and column analyses correspondence analysis can be applied to find out which characters can be used to construct identification keys and to selectively group variables by their importance for the discrimination of samples.

Cluster Analysis↗
PubMed1993

Analyzing individual status and change with hierarchical linear models: illustration with depression in college students.

A recently developed class of multilevel or hierarchical linear models (HLM) provides an intuitive and efficient way to estimate individual growth or change curves. The approach also models the between-subjects variation of the individual change curves with treatment factors and individual attributes. Unlike other repeated measures analysis methods common in the behavioral sciences, HLM allows the fit of data with unequal numbers of repeated observations for each subject, variable timing of observations, and missing data, features which are often characteristic of data from field studies. The application of HLM for the analysis of repeated psychological measures is discussed and illustrated here with depression data for college students. Strengths and limitations of the approach are discussed.

Adaptation, Psychological↗
PubMed1991

Descriptive study of prognostic factors influencing survival of compensated silicotic patients.

The objective of this study was to assess survival and the prognostic influencing survival of compensated silicotic patients. All workers compensated for silicosis in the Province of Quebec from 1938 to 1985 (n = 1,165) were included. Clinical data were those collected during the exam that led to a compensation decision. Due to missing data, a subcohort of 961 patients was used for multivariate analysis of clinical prognostic factors with the Cox proportional hazards model. The following factors made an independent contribution to survival: age at compensation, smoking, dyspnea, expectoration, abnormal breath sounds, radiographic appearance, and vital capacity. On the basis of the model, patients with small opacities alone on their chest radiograph and who did not have dyspnea, expectoration, or abnormal breath sounds had a survival similar to the average Quebec man; other patients had a poorer survival. We conclude that it is possible to identify at the time of compensation, silicotic patients who are likely to have a life expectancy similar to that of the general population. Symptoms and physical signs as well as radiographic and lung function abnormalities appear to be useful prognostic indicators in compensated silicotic patients.

Dyspnea↗
PubMed1999

National birthweight percentiles by gestational age for twins born in Australia.

OBJECTIVE: To develop national charts of birthweight percentiles by gestational age and infant sex for liveborn twins born in Australia. METHODOLOGY: National data on live twin births to non-Indigenous Australian-born mothers during 1991-94 were derived from perinatal data collected by midwives in each State and Territory. RESULTS: During 1991-4 there were 20,075 liveborn twin infants. Of these births, missing data included: birthweight 36 (0.2%) births, gestational age 95 (0.5%) births, and sex (missing or indeterminate) 13 (0.06%) births. These births were excluded from the study. An additional 0.6% births were excluded because the recorded birthweights were extreme outliers for the recorded gestational ages. Forty-seven per cent of live twin births were preterm (< 37 weeks). At all gestational ages, the median birthweight of male twins was higher than that of female twins. At model gestational age of 38 weeks, the difference in the median birthweight was 130 g. CONCLUSIONS: The charts produced as a result of the study provide birthweight percentiles by gestational age for twins based on national data in Australia. They provide current population norms for the use of Australian clinicians and researchers.

Adult↗
PubMedDate not supplied

Gestational age reporting and preterm delivery.

This study examines recent trends in the reporting completeness and quality of gestational age estimates derived from the date of the last normal menses (DLNM) as reported in South Carolina vital records from 1974 to 1985. Noteworthy improvements in the completeness of reporting emerged during this period with a decline from 31.1 percent missing information in 1974 to 6.6 percent missing in 1985. Completeness of reporting and strategies for imputing values for missing data were analyzed for their impact on the calculation of the percentage of preterm live births. The results indicate that the underreporting of gestational age can lead to marked underestimation of the preterm percentage in a population and to misinterpretation of trends in these percentages. Based on the results of this analysis, it is recommended that preterm percentages be based on cases with DLNM gestational age values between 20 and 50 weeks. Since cases with missing or implausible gestational age data have a greater risk of a poor pregnancy outcome, these findings emphasize the importance of identifying both the completeness of data reporting and the use of imputation and deletion strategies when employing population-based DLNM data to calculate gestational age related indicators.

Adolescent↗
PubMed1997

Comparative calibration without a gold standard.

Comparative calibration is the broad statistical methodology used to assess the calibration of a set of p instruments, each designed to measure the same characteristic, on a common group of individuals. Different from the usual calibration problem, the true underlying quantity measured is unobservable. Many authors have shown that this problem, in general, does not have a unique solution. Most commonly used assumptions to obtain a unique solution are (i) one instrument is the gold standard (that is, unbiased) and (ii) the measurement errors of the p instruments are independent. Such constraints, however, may not be valid for many clinical applications, for example, the universal standardization project for dual X-ray absorptiometry (DXA) scanners. In this paper, we propose a new approach to resolve the comparative calibration problem when a gold standard is unavailable. Instead of the usual assumptions, we use external information in addition to data from the p instruments, to solve the problem. We address statistical estimation, hypothesis testing and missing data problems. We apply the new method specifically to the universal standardization project data where a group of individuals have been measured for bone mineral density (BMD) by three DXA scanners. We compare the results of the new method to currently used methods and show that they have better statistical properties.

Absorptiometry, Photon↗
PubMed1985

Out-of-pocket health expenses for Medicaid and other poor and near-poor persons in 1980.

The Medicaid program (Title XIX of the Social Security Act) was designed to provide access to health services at little or no out-of-pocket expense to low-income persons who might otherwise not be able to afford them. Information was collected through household interviews in the National Medical Care Utilization and Expenditure Survey (NMCUES) on total out-of-pocket expenditures for health care by noninstitutionalized persons in the United States in 1980. This report presents data to assess the degree to which Medicaid enrollees incur out-of-pocket expenses. These levels of expenditures are compared to those experienced by other persons not eligible for Medicaid who are below or near the official poverty level. Data contained in this report were derived from the National Household Survey (HHS), a panel survey of 6,600 households representative of the civilian, noninstitutionalized U.S. population, which is only one of the three surveys that were conducted as part of NMCUES. The other two surveys are a State Medicaid Household Survey (SMHS) of Medicaid households in four States and the Administrative Records Survey (ARS), a survey of existing Medicare and Medicaid administrative records for sample households. Since data were derived only from HHS, the findings in this report are national (or regional) in scope and cannot be tied directly to differences in individual State Medicaid programs. The data on eligibility and expenditures are all self-reported and have not been verified by administrative records. One definite limitation of these data is the exclusion from the NMCUES sample of all institutionalized persons. As a result, out-of-pocket expenses for one particularly high-cost group are excluded, and total out-of-pocket expenditures for each health insurance coverage group are understated. Another potential limitation of this analysis is that, as with many surveys, limited data on key items (such as out-of-pocket expenses and income) were at times missing from respondent reports. These missing data were imputed according to standard statistical techniques (see Appendix III). A variety of findings is presented, including data on the effect of health insurance coverage, demographic characteristics, health status, and continuity of Medicaid enrollment on out-of-pocket expenses. Within insurance coverage categories, Medicaid-covered persons had the lowest out-of-pocket expenses. This was true even though they had the highest mean per capita charges for care. Among the demographic characteristics that were analyzed, age and race had the most impact on the level of out-of-pocket health expenses.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed2000

Mixed-effects models in psychophysiology.

The current methodological policy in Psychophysiology stipulates that repeated-measures designs be analyzed using either multivariate analysis of variance (ANOVA) or repeated-measures ANOVA with the Greenhouse-Geisser or Huynh-Feldt correction. Both techniques lead to appropriate type I error probabilities under general assumptions about the variance-covariance matrix of the data. This report introduces mixed-effects models as an alternative procedure for the analysis of repeated-measures data in Psychophysiology. Mixed-effects models have many advantages over the traditional methods: They handle missing data more effectively and are more efficient, parsimonious, and flexible. We described mixed-effects modeling and illustrated its applicability with a simple example.

Algorithms↗
PubMed1989

Investigating drug plasma levels and clinical response using random regression models.

The reanalysis of the Riesby dataset using a random regression model indicates a significant effect of DMI plasma measurements on HAM-D scores across the four timepoints of the study. This effect is especially strong when the HAM-D change from baseline score is used in place of the actual HAM-D score at the four timepoints. A significant effect of IMI was not found for either the actual HAM-D score or the HAM-D change from baseline score. An endogenous effect was marginally significant when the actual HAM-D score was used; however, this effect was not observed when the HAM-D change score was used as the dependent measure. There also was evidence of a marginally significant effect due to autocorrelation of the residuals, indicating that the residuals at a given timepoint were related to the residuals from previous timepoints according to a first-order autoregressive process. In contrast, when the repeated measures MANOVA was used to analyze these data, a significant effect of DMI was not observed, since subjects without complete data at all timepoints had to be dropped from the analysis. In longitudinal psychiatric studies where missing data are the rule (rather than the exception), the random regression approach provides an attractive alternative to the traditional methods of analyzing longitudinal data.

Humans↗
PubMed2000

Zuclopenthixol decanoate for schizophrenia and other serious mental illnesses.

BACKGROUND: There is a clear link between stopping antipsychotic medications and a relapse of psychotic symptoms. A series of long-acting intra-muscular preparations has been developed since the 1960s in the hope of reducing the frequency of relapse and, hence, overall disability. These depot preparations, active for weeks at a time, are frequently used for those who find taking oral medication on a regular basis difficult or unacceptable. It has, however, been a consistent concern that any reduction in relapse rate afforded by depot preparations may be offset by an increase in adverse effects such as drug-induced movement disorders. OBJECTIVES: To compare zuclopenthixol decanoate to oral zuclopenthixol and other antipsychotic preparations for the treatment of schizophrenia and similar serious mental illness. SEARCH STRATEGY: Electronic searches of Biological Abstracts (1982-1998), CINAHL (1982-1998), The Cochrane Library (Issue 2, 1998), The Cochrane Schizophrenia Group's Register (April 1998), EMBASE (1980-1998), MEDLINE (1966-1998), and PsycLIT (1974-1998) were searched. References of all eligible studies were searched for further trials. The manufacturer of zuclopenthixol was contacted. SELECTION CRITERIA: Inclusion criteria were that the clinical study should be randomised, focus on people with schizophrenia or other serious mental illness with psychotic symptoms, and compare the use of zuclopenthixol decanoate to oral zuclopenthixol or other antipsychotic preparations. DATA COLLECTION AND ANALYSIS: Data was extracted independently by two reviewers (EC, MF). Authors of trials were contacted for additional and missing data. Odds ratios (ORs) and 95% confidence intervals (CIs) of homogenous dichotomous data were calculated with the Peto method. Where possible the number needed to treat (NNT) and its 95% confidence interval was also calculated. MAIN RESULTS: Four studies relating to zuclopenthixol decanoate were included. All compared zuclopenthixol decanoate with other depot preparations. Zuclopenthixol decanoate prevented or postponed relapses when compared to other depots (NNT 8, CI 5-53). However, zuclopenthixol decanoate may induce more adverse effects (NNH 5, CI 3-31) although it decreases need for anticholinergic medication when compared to a group of other depot preparations (NNT 9, CI 5-38). For the risk of leaving the study early, there was also a trend for benefit to those allocated to zuclopenthixol decanoate. None of the studies reported outcomes on service utilisation, costs, or quality of life. REVIEWER'S CONCLUSIONS: Choice of which depot to use must always take into account clinical judgement and the preferences of the recipients of care and their carers. Limited trial data suggests, however, that there are real differences between zuclopenthixol decanoate and other depots and these differences largely favour the former. This review highlights the need for good controlled clinical trials to fully address the effects of zuclopenthixol decanoate for those with schizophrenia. Future studies should report service utilisation data, as well as satisfaction with care and economic outcomes. Duration of such trials should be of a longer duration than the included studies (12 months or more).

Administration, Oral↗
PubMed2000

Riluzole for amyotrophic lateral sclerosis (ALS)/motor neuron disease (MND).

BACKGROUND: Riluzole has been approved for treatment of patients with amyotrophic lateral sclerosis (ALS) in some countries but not others. Questions persist about its clinical utility because of high cost, modest efficacy and concern over adverse effects. OBJECTIVES: To examine the efficacy of riluzole in prolonging survival, and in delaying the use of surrogates (tracheostomy and mechanical ventilation) to sustain survival. SEARCH STRATEGY: Search of the Cochrane Neuromuscular Disease Group Register for randomized trials and enquiry from authors of trials and other experts in the field. The most recent search was conducted in June 1999. SELECTION CRITERIA: Types of studies: randomized trials TYPES OF PARTICIPANTS: adults with a diagnosis of ALS Types of interventions: treatment with riluzole or placebo Types of outcome measures: Primary: per cent mortality at 12 months with riluzole 100 mg Secondary: per cent mortality as a function of time with 100 mg and with all doses of riluzole, scales of neurologic function, quality of life, muscle strength and adverse events. DATA COLLECTION AND ANALYSIS: We identified two randomized trials. Each reviewer graded them for methodological quality. Data extraction was performed by a single reviewer and checked by the other two. We obtained some missing data from investigators. We performed meta-analyses with RevMan software using a fixed effects model. MAIN RESULTS: The two eligible trials included a total of 794 riluzole treated patients and 320 placebo treated patients. The methodological quality was acceptable and the trials were easily comparable. There were significant differences between the riluzole and placebo groups of both trials, in terms of the primary outcome measure, which was per cent mortality at 12 months with the 100 mg dose of riluzole. The odds ratio for the combined studies was 0.57 (95%CI 0.41 to 0.80) at 12 months. In the secondary outcome measures, there was a survival advantage with riluzole 100 mg at six, nine, 12 and 15 months, but not at three or 18 months. Pooled data from the 50, 100 and 200mg dose groups in the larger trial showed a lower per cent mortality with riluzole compared to placebo only at 12 months (odds ratio (OR) 0.64, 95% CI 0.47 to 0.88). There was no beneficial effect on bulbar function, or muscle strength. There were scant data on quality of life, but patients treated with riluzole remained in a more moderately affected health state significantly longer than placebo-treated patients (weighted mean difference (WMD) 35.5 days, 95% CI 5.9 to 65. 0). A threefold increase in serum alanine transferase was more frequent in riluzole treated patients than controls (WMD 2.65, 95% CI 1.51 to 4.65). REVIEWER'S CONCLUSIONS: Riluzole 100 mg per day appears to be modestly effective in prolonging survival for patients with ALS.

Amyotrophic Lateral Sclerosis↗
PubMed2000

Inhaled nitric oxide for acute hypoxemic respiratory failure in children and adults.

OBJECTIVES: To determine the effect of iNO, compared with inhaled placebo, on outcome in AHRF in children and/or adults. SEARCH STRATEGY: Randomised controlled trials (RCT's) were identified from electronic databases; MEDLINE, EMBASE, the Cochrane Library, and CINAHL, as well as from bibliographies of retrieved articles. Relevant journals and conference proceedings were hand searched and authors published in this field were contacted for knowledge of unpublished ongoing trials. SELECTION CRITERIA: RCT's comparing iNO with maximal conventional therapy and inhaled placebo, for AHRF in either children or adults. DATA COLLECTION AND ANALYSIS: Data were extracted and the analyses performed independently by two reviewers. All 5 authors were contacted for missing data. Qualitative assessment of each trial was made according to methodology described by Schulz (Schulz 1995), and analyses according to statistical methods in Review Manager MetaView 3.1. The fixed effect model was applied. Where possible, sub-group analyses were performed to assess the impact of iNO in varied doses. MAIN RESULTS: Five RCT's were evaluated, assessing 535 patients with AHRF. Inhaled nitric oxide made no impact on mortality in trials without cross-over (RR 0.98, 95%CI 0.66, 1.44), or with cross-over of treatment failures to open-label iNO (RR 1.22, 95%CI 0.65, 2.29). Published evidence from one study demonstrated that iNO resulted in a transient improvement in oxygenation in the first 24 hours of treatment: the oxygenation index (OI) showed a mean difference of -3 [95% CI -5.354, -0.646], and PaO2/FiO2 ratio, a mean difference of 35 [95% CI 20.236, 49.764]. Limited data demonstrated no difference in ventilator-free days between treatment and placebo groups, and no specific dose of iNO was significantly advantageous over another. Other clinical indicators of effectiveness, such as duration of hospital and intensive care stay, were inconsistently reported. There were no complications reported to be directly attributable to this treatment. REVIEWER'S CONCLUSIONS: From the data provided to date, iNO had no effect on mortality and only transiently improved oxygenation in AHRF in children and/or adults. There was a lack of data to assess other end points. The long term adverse effects of this drug are not known, as no long term follow-up of trial participants has been reported. If further trials comparing iNO with an inhaled placebo are to proceed, they should be stratified for primary disease and must specifically evaluate clinically relevant outcomes, before any benefit of iNO in AHRF can be excluded.

Acute Disease↗
PubMed1996

Influence of gender on outcomes of medication-history interviewing.

This study investigated the influence of patient and provider gender on the outcomes of medication-history interviewing. In a previous study, 112 pharmacy students conducted medication-history interviews with 2 simulated patients. A secondary analysis was accomplished using complete data from 85 of the original 112 pharmacy students. The other 27 students were eliminated because of missing data. Factor analysis and canonical correlation were used to assess associations between the prior study's set of predictor variables and measures of interview completeness and patient satisfaction with the interview. Female and male pharmacy students appear to use different expressive, interactive, and interrogative skills. Allergy-asking was more complete when female pharmacy students interviewed a male patient. Emotive patient satisfaction was found to be associated more positively with a female student and female patient while teleological patient satisfaction between a male student and male patient was nearly double the result of the female-female dyad. Medication-history interview outcomes appear to differ as a consequence of the use of different sets of skills during same-sex or opposite-sex interviews.

Clinical Competence↗
PubMed1993

Effect of antipsychotic withdrawal on extrapyramidal symptoms: statistical methods for analyzing single-sample repeated-measures data.

Using symptom severity ratings of extrapyramidal side effects (EPS) during a 4-week antipsychotic washout period, we illustrate particular problems associated with repeated measures of symptom severity and demonstrate four analysis methods. The often suggested analysis of variance and multivariate analysis of variance found no mean change in weekly Simpson Angus scores over the 4-week washout despite the fact that 43% had clinically significant EPS prior to drug discontinuation. On the other hand, the Friedman Analysis of Ranks and Cochran-Mantel-Haenszel (CMH) statistics found significant change over the washout period. These two less well-known techniques place fewer restrictions on the data, can be more sensitive to patterns of change, and may be more appropriate for psychiatric data. The CMH method is particularly attractive since it does not require complete data on all subjects as do many other techniques. This minimizes the number of cases lost to missing data and increases the generality of the results.

Adult↗