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PubMed2002

Cost-effectiveness of screening for the possible development of cancer in patients with oral lichen planus.

INTRODUCTION: Several authors have expressed the view that patients with oral lichen planus (OLP) are at increased risk of developing oral cancer. Since OLP cannot be effectively treated, regular screening for the possible development of oral cancer might be considered. OBJECTIVES: (i) To calculate costs and effectiveness of screening for oral cancer in OLP patients with a decision model; (ii) to compare the cost-effectiveness of different screening scenarios; and (iii) to perform a sensitivity analysis of several variables used in this model. METHODS: Costs and effectiveness of a population of 100,000 OLP patients, being either screened or not screened for oral cancer, were calculated for the period of 1 year. Health gain was expressed as quality adjusted live years (QALY's) and equivalent lives saved (ELS). Cost-effectiveness was expressed as extra costs (costs of screening minus costs of no screening) per ELS. Then, the outcome was compared with the cost-effectiveness of a different screening scenario. Finally, the effect of varying the variables: (i) costs of cancer treatment; (ii) annual malignant transformation rate (MTR); (iii) sensitivity and specificity of an oral examination; and (iv) proportion of cancers found in stage I on extra costs per ELS were assessed in a sensitivity analysis. RESULTS: The health gain from screening was 592 QALY's or the equivalent of 23.68 lives saved, costing 1,265,229 dollars, meaning that one ELS costed 53,430 dollars. Increase of cancer-treatment costs will significantly decrease the costs per ELS. When the MTR is lower than 0.4% per year, extra costs per ELS will increase exponentially. The effect of sensitivity and specificity of an oral examination in detecting oral cancer on cost-effectiveness seems to be substantial. When the proportion of cancers found in stage I can be increased from 40% (without screening) up to at least 60% after screening, extra costs per ELS will decrease exponentially. CONCLUSIONS: Screening for oral cancer in OLP patients, based on the presently used model, seems attractive. However, varying the several variables in the decision model has a significant impact on the final costs and effectiveness. Only, when additional information about these variables will become available, a more precise and realistic calculation can be performed.

Cell Transformation, Neoplastic↗
PubMed2004

A cost-effectiveness analysis of docetaxel in the second-line treatment of non-small cell lung cancer.

BACKGROUND: Whilst lung cancer is the most common form of cancer in England and Wales (annual incidence rate of 50 per 100,000) it does not always receive the policy attention accorded to other types of cancer, such as breast and colorectal. Nevertheless, the burden of lung cancer is significant and the UK NHS Plan for cancer has set out the government's commitment to improving all cancer services. The question faced by the NHS is which interventions are most cost effective in implementing this plan. OBJECTIVE: To develop a model to assess the economics of second-line treatment of non-small cell lung cancer (NSCLC) from the perspective of the UK NHS, based on the resources and outcomes from the pivotal clinical study comparing docetaxel 75 mg/m(2) with best supportive care (BSC). METHODS: The area under the survival curve for each treatment was analysed and the difference in mean survival between the docetaxel group and the BSC group was calculated as 3.82 months. Measurable incremental costs for the docetaxel group were largely driven by drug acquisition and administration. These cost drivers, as well as toxicity treatment costs and cost offsets, were varied in the sensitivity analysis. Although the overall timeframe for the model was 2 years, discounting was not applied as the resources and benefits of docetaxel use in this setting are realised relatively immediately. RESULTS: The base case cost-effectiveness analysis (mean values) reported a cost per life-year gained of 13,863 pounds sterling for docetaxel 75 mg/m(2) (year 2000/2001 values). Sensitivity analysis showed that the number of treatment cycles per patient, which affected total treatment cost, had most influence on the cost per life-year gained in the base case scenario. Using the 95% confidence intervals around the mean number of treatment cycles, the base case cost per life-year gained varied from 10,985 pounds sterling to 16,738 pounds sterling. Using the 95% confidence intervals around the mean difference in survival, to represent best and worst case scenarios, the cost per life-year saved ranged from 10,020 pounds sterling to 32,781 pounds sterling . CONCLUSION: This model suggests, with its underlying assumptions and data, docetaxel 75 mg/m(2) in 3-weekly cycles is a cost-effective second-line treatment, from the perspective of the NHS, for pretreated NSCLC in terms of survival gains made for a reasonable increase in costs.

Antineoplastic Agents, Phytogenic↗
PubMed2005

Biomechanical analysis of the shear behaviour adjacent to an axially loaded implant.

Good mechanical fixation of an implant to the surrounding bone is important for its longevity, and is influenced by both biological and mechanical factors. This study parametrically evaluates the mechanics of the interface with a computationally efficient analytic structural model of the shear stress field and global shear stiffness of an axially loaded implant. The utility of the analytic model was first established by validating its assumptions with a case-specific finite element model. We then used the analytic model for a sensitivity analysis of the relationship between the pattern of tissue growth and shear properties of the interface for our previously reported loaded in vivo experimental micromotion device. The bone located directly at the implant surface was found to be the most effective site for increasing interface stiffness. This suggests that the implant surface is the most desirable site for bone growth, yet is also the most mechanically challenging environment due to its maximal shear stresses. Thus, these findings support the further investigation of osteo-conductive coatings and other biological stimuli to overcome the challenging mechanics, and to promote bone growth directly at the implant surface. The model also demonstrated that the mechanical contribution to the global implant shear stiffness of a commonly observed isolated sclerotic bone rim is very limited. The results of this sensitivity analysis agree with experimental studies with the micromotion device, and with clinical studies reporting good results with osteo-conductive coatings.

Animals↗
PubMed2001

Continuous subglottic suctioning for the prevention of ventilator-associated pneumonia : potential economic implications.

STUDY OBJECTIVE: To determine the cost-effectiveness of continuous subglottic suctioning (CSS) as a strategy to decrease the incidence of ventilator-associated pneumonia (VAP). DESIGN: Decision-model analysis of the cost and efficacy of endotracheal tubes that allow CSS at preventing VAP. The primary outcome was cases of VAP averted. Model estimates were based on data from published prospective trials of CSS and other prospective studies of the incidence of VAP. SETTING AND PATIENTS: Hypothetical cohort of 100 patients requiring nonelective endotracheal intubation and management in an ICU. INTERVENTIONS: In the model, patients were managed with either traditional endotracheal tubes (ETs) or ETs capable of CSS. MEASUREMENTS AND MAIN RESULTS: The marginal cost-effectiveness of CSS was calculated as the savings resulting from cases of VAP averted minus the additional costs of CSS-ETs, and expressed as cost (or savings) per episode of VAP prevented. Sensitivity analysis of the impact of the major clinical inputs on the cost-effectiveness was performed. The base case assumed that the incidence of VAP in patients requiring > 72 h of mechanical ventilation (MV) was 25%, that CSS-ETs had no impact on patients requiring MV for < 72 h, and that CSS-ETs resulted in a relative risk reduction of VAP of 30%. Despite the higher costs of ETs capable of CSS, this tactic yielded a net savings of $4,992 per case of VAP prevented. For sensitivity analysis, model inputs were adjusted by 50% individually and then simultaneously. This demonstrated the model to be only moderately sensitive to the calculated cost of VAP. With the relative risk reduction at 50% of the base-case estimate, CSS resulted in $1,924 saved per case of VAP prevented. When all variables were skewed against CSS, total outlays were trivial (approximately $14 per patient in the cohort). CONCLUSIONS: CSS represents a strategy for the prevention of VAP that may result in savings. Further studies are warranted to confirm the efficacy of CSS.

Cohort Studies↗
PubMed1995

Cost effectiveness of antenatal screening for cystic fibrosis.

OBJECTIVE: To estimate the cost effectiveness of different antenatal screening programmes for cystic fibrosis. SETTING: Antenatal clinics and general practices in the United Kingdom. DESIGN: Four components of the screening process were identified: information giving, DNA testing, genetic counselling, and prenatal diagnosis. The component costs were derived from the literature and from a pilot screening study in Yorkshire. The cost of a given screening programme was then obtained by summing the components according to the specific screening strategy adopted (sequential and couple), the proportion of carriers detected by the DNA test, and the uptake of screening. Baseline assumptions were made about the proportion with missing information on carrier status from previous pregnancies (20%), the proportion changing partners between pregnancies (20%), and the uptake of prenatal diagnosis (100%). Sensitivity analysis was performed by varying these assumptions. MAIN OUTCOME MEASURE: Cost per affected pregnancy detected. RESULTS: Under the baseline assumptions sequential screening costs between pounds 40,000 and pounds 90,000 per affected pregnancy detected, depending on the carrier detection rate and uptake. Couple screening was more expensive, ranging from pounds 46,000 to pounds 104,000. From the sensitivity analysis a 10% change in the assumed proportion with missing information from a previous pregnancy alters the cost by pounds 4000; a 10% change in the proportion with new partners has a similar effect but only for couple screening; and cost will change directly in proportion to the uptake of prenatal diagnosis. CONCLUSIONS: While economic analysis cannot determine screening policy, the paper provides the NHS with the information on cost effectiveness needed to inform decisions on the introduction of a screening service for cystic fibrosis.

Cost-Benefit Analysis↗
PubMed2004

Underestimation of risk due to exposure misclassification.

Exposure misclassification constitutes a major obstacle when developing dose-response relationships for risk assessment. A non-differentional error results in underestimation of the risk. If the degree of misclassification is known, adjustment may be achieved by sensitivity analysis. The purpose of this study was to examine the full magnitude of measurement error in determining the prenatal exposure to methylmercury. We used data from a prospective study of a Faroese birth cohort. Two biomarkers of methylmercury exposure were available, i.e., the mercury concentrations in cord blood and in maternal hair (sampled at the time of parturition). The laboratory imprecision on both chemical analyses was thought to be below 5% coefficient of variation (CV). As a third exposure parameter, we used the dietary questionnaire response on frequency of whale meat dinners. Factor analysis and structural equation analysis were applied to assess the full extent of the imprecision. The calculated total imprecision much exceeded the known laboratory variation: the CV was 28-30% for the cord-blood concentration and 52-55% for the maternal hair concentration. The dietary questionnaire response was even more imprecise. These findings illustrate that measurement error may be greatly underestimated if judged solely from reproducibility or laboratory quality data. Adjustment by sensitivity analysis is meaningful only if realistic measurement errors are applied. When exposure measurement errors are overlooked or underestimated, decisions based on the precautionary principle will not appropriately reflect the degree of precaution that was intended.

Biomarkers↗
PubMed2000

Intravenous immunoglobulin for suspected or subsequently proven infection in neonates.

BACKGROUND: Congenital and nosocomial infections are important causes of neonatal morbidity and mortality. Maternal transport of immunoglobulins to the fetus mainly occurs after 32 weeks gestation and endogenous synthesis does not begin until several months after birth. Administration of intravenous immunoglobulin provides IgG that can bind to cell surface receptors, provide opsonic activity, activate complement, promote antibody dependent cytotoxicity, and improve neutrophilic chemoluminescence. Theoretically infectious morbidity and morbidity could be reduced by the administration of intravenous immunoglobulin. OBJECTIVES: To assess the effectiveness of intravenous immunoglobulin (IVIG) to reduce mortality/morbidity caused by suspected infection in newborn infants. In secondary analyses to assess the effectiveness of IVIG to reduce mortality/morbidity in those neonates who entered into the studies with suspected infection and who later were confirmed as being infected. SEARCH STRATEGY: Medline, Embase, and Reference Update Databases were searched in November 1997, and the Cochrane Library in July 1998 using the following keywords: immunoglobulin and infant-newborn, and random allocation, or controlled trial, or randomized controlled trial (RCT). The reference lists of identified RCTs and meta-analyses, personal files and Science Citation Index were also searched. No language restrictions were applied. Unpublished data were requested from authors and information has been obtained from one author to date. SELECTION CRITERIA: The criteria used to select studies for inclusion were: 1) DESIGN: RCT (including quasi-randomized trials) 2) Newborn infants (< 28 days old) 3) INTERVENTION: IVIG for treatment of suspected (and in some infants subsequently proved) bacterial/fungal infection compared to placebo or no intervention. Suspected infection was defined as clinical symptoms and signs consistent with infection without isolation of causative organism. Proved infection was defined as: clinical symptoms and signs consistent with infection in association with isolation of causative organism from either blood culture, cerebrospinal fluid culture, urine culture (urine obtained by suprapubic tap) or a normally sterile site (e.g., liver, spleen, meninges, lung) at autopsy. 4) At least one of the following outcomes was reported: mortality during initial hospital stay; length of hospital stay; side effects; psychomotor development/growth at follow up. DATA COLLECTION AND ANALYSIS: Two reviewers independently abstracted information for the outcomes of interest and one researcher (AO) checked for any discrepancies and pooled the results. Relative risk (RR) and Risk Difference (RD) with 95% confidence intervals (CI) using the fixed effects model are reported for dichotomous outcomes and weighted mean difference (WMD) for continuous data. NNT was calculated for outcomes that showed a statistically significant reduction in RD. Data from quasi-randomized trials were excluded in sensitivity analyses. MAIN RESULTS: Study quality was generally poor. Four of 7 identified studies (n = 208), reported on the outcomes of all randomized patients with clinically suspected infection. Mortality was reduced [RR 0.52 (95% CI; 0.28, 0.98), RD -0.102 (95% CI; -0.005, -0.199, NNT 10 (95% CI; 5, 200]. When, in a sensitivity analysis (n = 126), the results from a quasi-randomized trial (n = 82) were excluded, RR and RD remained similar, [RR 0.53 (95% CI; 0.25, 1.15), RD -0.106 (-0.232, 0.021)] but statistical significance was lost. Treatment with IVIG (six trials, n = 234) in cases of subsequently proved infection did not result in a statistically significant reduction in mortality [RR 0.62 (95% CI; 0.34, 1.12, RD -0.074 (95% CI; -0.163, 0. 014)]. Excluding in a sensitivity analysis (n = 199) a quasi-randomized trial (n = 35) changed the results slightly [RR 0. 68 (95% CI; 0.36, 1.29), RD -0.059 (-0.152, 0.035)]. There was no statistically significant between-study

Humans↗
PubMed2001

A mathematical model for malaria transmission relating global warming and local socioeconomic conditions.

OBJECTIVE: Sensitivity analysis was applied to a mathematical model describing malaria transmission relating global warming and local socioeconomic conditions. METHODS: A previous compartment model was proposed to describe the overall transmission of malaria. This model was built up on several parameters and the prevalence of malaria in a community was characterized by the values assigned to them. To assess the control efforts, the model parameters can vary on broad intervals. RESULTS: By performing the sensitivity analysis on equilibrium points, which represent the level of malaria infection in a community, the different possible scenarios are obtained when the parameters are changed. CONCLUSIONS: Depending on malaria risk, the efforts to control its transmission can be guided by a subset of parameters used in the mathematical model.

Animals↗
PubMed1999

Uncertainty in the relation between exposure to magnetic fields and brain cancer due to assessment and assignment of exposure and analytical methods in dose-response modeling.

Incomplete scientific knowledge ensures that, in every study, uncertainty will enter the processes of exposure estimation and exposure-response modeling. In the light of the heated debate about the health effects of magnetic fields resulting from power production and usage, we undertook a sensitivity analysis to evaluate uncertainty related to key decisions in a previous study of brain cancer and occupational exposure to magnetic fields. The findings appeared to be relatively insensitive to most variations in the methods of exposure assessment, exposure assignment, and data analysis. The results can be visualized by defining bands of uncertainty about a best-bet estimate of the association based on our original study. These bands of methodological uncertainties were similar in magnitude to the conventional 95% confidence interval, but they provide a measure of the potential range of systematic bias in the results, rather than reflecting statistical variability alone. The methodology employed here can be applied to other studies, and other researchers are encouraged to conduct sensitivity analysis in order to estimate methodological uncertainty as an alternative to statistical confidence intervals.

Adult↗
PubMed2005

Quantitative assessment of the glyoxalase pathway in Leishmania infantum as a therapeutic target by modelling and computer simulation.

The glyoxalase pathway of Leishmania infantum was kinetically characterized as a trypanothione-dependent system. Using time course analysis based on parameter fitting with a genetic algorithm, kinetic parameters were estimated for both enzymes, with trypanothione derived substrates. A K(m) of 0.253 mm and a V of 0.21 micromol.min(-1).mg(-1)for glyoxalase I, and a K(m) of 0.098 mm and a V of 0.18 micromol.min(-1).mg(-1) for glyoxalase II, were obtained. Modelling and computer simulation were used for evaluating the relevance of the glyoxalase pathway as a potential therapeutic target by revealing the importance of critical parameters of this pathway in Leishmania infantum. A sensitivity analysis of the pathway was performed using experimentally validated kinetic models and experimentally determined metabolite concentrations and kinetic parameters. The measurement of metabolites in L. infantum involved the identification and quantification of methylglyoxal and intracellular thiols. Methylglyoxal formation in L. infantum is nonenzymatic. The sensitivity analysis revealed that the most critical parameters for controlling the intracellular concentration of methylglyoxal are its formation rate and the concentration of trypanothione. Glyoxalase I and II activities play only a minor role in maintaining a low intracellular methylglyoxal concentration. The importance of the glyoxalase pathway as a therapeutic target is very small, compared to the much greater effects caused by decreasing trypanothione concentration or increasing methylglyoxal concentration.

Animals↗
PubMed2006

Two-dimensional reverse phase-reverse phase chromatography: A simple and robust platform for sensitive quantitative analysis of peptides by LC/MS. Hardware design.

We have revised current two-dimensional RP-RP approaches and developed a new robust 2-D RP-RP platform. This platform was implemented on an Agilent 1100 2-D liquid chromatography system and is based on high pressure switching between two high-resolution RP columns. An independent binary gradient was implemented for each dimension. The powerful combination of dual analytical columns with independent gradient elution achieves high analyte purity, effectively eliminates matrix effects, and maximizes MS sensitivity in Q1 SIM comparable to the sensitivity enhancements of MS/MS-based methods. Implementation of dual simultaneous gradient profiles (overlapped gradients) reduces 2-D method run-time to the scale of 1-D method run-times. This robust and sensitive approach is particularly suitable for hydrophobic peptides and small proteins and can be used as a routine standard technique for enhanced on-line peptide purification coupled with mass spectrometric detection.

C-Peptide↗
PubMed2005

Use of partial budgeting to determine the economic benefits of antibiotic treatment of chronic subclinical mastitis caused by Streptococcus uberis or Streptococcus dysgalactiae.

The economic effect of lactational antibiotic treatment of chronic subclinical intramammary infections due to Streptococcus uberis or Streptococcus dysgalactiae was explored by means of partial budgeting. Effects at cow level and herd level were modelled, including prevention of clinical mastitis episodes and the prevention of transmission of infections. Input variables for our deterministic model were derived from literature or based on 2002/2003 dairy prices and farming conditions in The Netherlands. Sensitivity analysis was used to examine the effect of uncertainty around input variables or changes in price estimates. On farms where pathogen transmission was prevented through proper udder health management, 3-d antibiotic treatment during lactation resulted in an average net profit of euro+11.62 over no treatment while 8-d antibiotic treatment had an average negative net result of euro-21.83. Sensitivity analysis showed that profitability depends on the probability of treatment-induced cure, pathogen transmission rates, culling rate, retention pay-off, and costs of antibiotic treatment. Three-day antibiotic treatment of chronic subclinical streptococcal mastitis is economically profitable over a range of input values for cure probabilities, transmission rates and losses due to culling. In contrast, 8-d lactational treatment is only profitable for very valuable animals, on farms where the risk of pathogen transmission is high and/or when the farmer is likely to cull a high percentage of cows with subclinical mastitis. Because bacterial flora, cow characteristics and management differ widely between farms, the economic outcome of lactational treatment of chronic subclinical streptococcal mastitis may be highly farm-dependent.

Animals↗
PubMed2000

Two-time window and multiangle photon correlation spectroscopy size and zeta potential analysis--highly sensitive rapid assay for dispersion stability.

Polysaccharide-stabilized iron oxide particles are highly potent contrast agents in magnetic resonance imaging. After intravenous injection, the size of these small or ultrasmall particles strongly influences their distribution in the body. Knowledge about the uniformity of particle size distribution within this particle size range is not accessible by laser diffraction (lower edge of detection range), and photon correlation spectroscopy (PCS) data only yield insufficient information, the so-called polydispersity index. A combination of two-time window and multiangle analysis makes detailed characterization of particle size distribution and particle aggregation feasible, which was shown using five different iron oxide dispersions. Additional particle charge characterization yielded conclusions about the type of stabilization present in the dispersion - electrostatic or steric stabilization. Thus, this thorough particle size and charge analysis is a tool for quick detection of broad particle distributions or aggregates.

Ferric Compounds↗
PubMed2002

Cost-effectiveness of prophylactic indomethacin in very-low-birth-weight infants.

OBJECTIVE: To perform cost-effectiveness analysis to facilitate the decision-making process surrounding use of indomethacin in preterm infants to lower the incidence of patent ductus arteriosus (PDA), intraventricular hemorrhage (IVH), and death. METHODS: A MEDLINE literature search from 1966 to July 2000 was performed to identify relevant randomized, controlled trials (RCTs), as well as cohort and retrospective case-control studies. A decision tree was built representing the choice to use or not use indomethacin, and the potential outcome costs. Probabilities of being in each chance node were obtained from this search. Where data probabilities were not clear, a sensitivity analysis was conducted. RESULTS: There was no difference in the expected survival per year; however, there was a significant difference when effectiveness was measured as quality-adjusted life years (QALYs), resulting in 11 and 10 years for the indomethacin and control groups, respectively. The indomethacin treatment cost was $95,157 and that of the control groups was $99,955. The cost effectiveness per life expectancy of being in the indomethacin and control groups was $7142 and $7727, respectively. The sensitivity analysis for PDA closure and prevention of IVH for infants eventually developing PDA versus those without PDA showed no difference. The cost-effectiveness analysis per QALY was $8443 for the indomethacin treatment and $9168 for the control group. CONCLUSIONS: The prophylactic use of indomethacin is less costly and more effective within an important range of certainty. However, this analysis does not include several potentially confounding factors, such as antenatal steroid use or indomethacin-induced renal toxicity. Depending on the frequency with which these factors arise, economic projections may be considerably altered against the early use of indomethacin.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2006

Cost effectiveness of olanzapine in prevention of affective episodes in bipolar disorder in the United Kingdom.

This study evaluated the cost effectiveness of olanzapine compared with lithium as maintenance therapy for patients with bipolar I disorder (BP1) in the UK. A Markov model was developed to assess costs and outcomes from the perspective of the UK National Health Service over a 1-year period. Patients enter the model after stabilization of a manic episode and are then treated with olanzapine or lithium. Using the findings of a recent randomized clinical trial, the model considers the monthly risk of manic or depressive episodes and of dropping out from allocated therapy. health care resources associated with acute episodes were derived primarily from a recent UK chart review. Costs of maintenance therapy and monitoring were also considered. Key factors influencing cost effectiveness were identified and included in a stochastic sensitivity analysis. The model estimated that, compared to lithium, olanzapine significantly reduced the annual number of acute mood episodes per patient from 0.81 to 0.58 (difference -0.23; 95% CI: -0.34, -0.12). Per patient average annual care costs fell by 799 UK pounds (95% CI: - 1,824 UK pounds, 59 UK pounds) driven by reduced inpatient days--but the cost difference was not statistically significant. Sensitivity analysis found the results to be robust to plausible variation in the model's parameters. The model estimated that using olanzapine instead of lithium as maintenance therapy for BP1 would significantly reduce the rate of acute mood events resulting in reduced hospital costs. Based on available evidence, there is a high likelihood that olanzapine would reduce costs of care compared to lithium.

Antipsychotic Agents↗
PubMed2001

Counselling for depression in primary care.

BACKGROUND: There is wide clinician and patient support for counselling in primary care, particularly in the UK. This review examines the effectiveness and cost effectiveness of counselling for psychological and psychosocial problems in the primary care setting. OBJECTIVES: To assess the effects of counselling in primary care by reviewing cost and outcome data for patients with psychological and psychosocial problems considered suitable for counselling. SEARCH STRATEGY: The search strategy included electronic searching of databases (including the CCDAN Register of RCTs and CCTs) along with handsearching of a specialist journal. Published and unpublished sources (clinical trials, books, dissertations, agency reports etc.) were searched, and their reference lists scanned. Contact was made with subject experts and CCDAN members. SELECTION CRITERIA: Randomised and controlled patient preference trials comparing counselling in primary care with usual general practitioner care for patients with psychological and psychosocial problems considered suitable for counselling. Trials completed before the end of April 1998 were included in the review. DATA COLLECTION AND ANALYSIS: Trials were independently assessed by at least two reviewers for appropriateness of inclusion and methdological quality. MAIN RESULTS: Four trials, involving 678 participants, of whom 487 were followed up, were included. Data for psychological symptom levels (four trials) were pooled statistically. Patients receiving counselling had significantly better psychological symptom levels post intervention than patients receiving usual general practitioner care (standardised mean difference -0.30, 95% CI, (-0.49 to - 0.11). The effect remained statistically significant when the results from studies with less rigorous methodology were excluded in a sensitivity analysis. Patients who received counselling tended to be more satisfied with their treatment (three trials). Health service utilisation data were reported in all trials reviewed, but only one trial undertook a cost analysis. No clear cost advantage was associated with either counselling or usual general practice care. REVIEWER'S CONCLUSIONS: Patients who received counselling were more likely to have improved psychological symptom levels than those who did not receive counselling. Levels of satisfaction with counselling were high. There is limited information about the cost effectiveness of counselling, with one study reporting no clear cost advantage with either counselling or general practice care. The four trials included in this review were all pragmatic trials of counselling in primary care in the UK, which reflect the reality of clinical provision in this context. There were methdological weaknesses identified in the studies, which should be taken into account when considering the results. The evidence base will be extended by trials of counselling which are nearing completion.

Controlled Clinical Trials as Topic↗
PubMed2002

The role of protective antireflux procedures in neurologically impaired children: a decision analysis.

BACKGROUND/PURPOSE: Despite normal clinical history and preoperative radiologic and pH studies, gastroesophageal reflux (GER) can become apparent in neurologically impaired (NI) children after gastrostomy tube placement. An antireflux procedure performed at the time of gastrostomy tube placement may prevent postoperative GER and help avoid the need for a subsequent surgical procedure but is associated with a high morbidity and mortality rate in NI children. The purpose of this study was to determine the role of protective antireflux procedures in NI children undergoing gastrostomy tube placement. METHODS: Decision analysis was used to evaluate the effect of a protective antireflux procedure on morbidity and mortality in NI children. The rate of postoperative GER, need for secondary antireflux procedures, and morbidity and mortality rates after gastrostomy tube placement with or without an antireflux procedure in NI children were estimated from the literature and expert opinion and used to construct decision trees. RESULTS: At baseline values, gastrostomy tube placement resulted in a lower morbidity (11% v 13%) than gastrostomy tube placement with a protective antireflux procedure. One-way sensitivity analysis showed that gastrostomy tube placement was the favored approach when the morbidity of gastrostomy tube placement was less than 11% or the morbidity of antireflux surgery was greater than 10%. At baseline values, gastrostomy tube placement resulted in a lower mortality rate (0.3% v 0.8%) than gastrostomy tube placement with a protective antireflux procedure. Using 1-way sensitivity analysis, no threshold value of any variable was found that favored the use of a protective antireflux procedure with respect to mortality. CONCLUSIONS: Although a protective antireflux procedure may reduce the need for additional surgery, inclusion of this procedure is associated with a higher morbidity and mortality rate. Initial placement of a gastrostomy tube without a protective antireflux procedure is the favored approach for NI children without preoperative evidence of GER.

Decision Trees↗
PubMed2000

Intravenous immunoglobulin for preventing infection in preterm and/or low-birth-weight infants.

BACKGROUND: Nosocomial infections continue to be a significant cause of morbidity and mortality among preterm and/or low birth weight infants. Maternal transport of immunoglobulins to the fetus mainly occurs after 32 weeks gestation and endogenous synthesis does not begin until several months after birth. Administration of intravenous immunoglobulin provides IgG that can bind to cell surface receptors, provide opsonic activity, activate complement, promote antibody dependent cytotoxicity, and improve neutrophilic chemoluminescence. Intravenous immunoglobulin thus has the potential of preventing or altering the course of nosocomial infections. OBJECTIVES: To assess the effectiveness/safety of intravenous immunoglobulin (IVIG) administration (compared to placebo or no intervention) to preterm (< 37 weeks gestational age at birth) and/or low birth weight (LBW) (< 2500 g BW) infants in preventing nosocomial infections. SEARCH STRATEGY: Medline, Embase, Cochrane Library and Reference Update Databases were searched in November 1997 using keywords: immunoglobulin and infant-newborn and random allocation or controlled trial or randomized controlled trial (RCT). The reference lists of identified RCTs, personal files and Science Citation Index were searched. No language restrictions were applied. SELECTION CRITERIA: The criteria used to select studies for inclusion in this overview were: 1) DESIGN: RCTs in which administration of IVIG was compared to a control group that received a placebo or no intervention. 2) POPULATION: preterm (< 37 weeks gestational age) and/or LBW (<2500 g) infants. 3) INTERVENTION: IVIG for the prevention of bacterial/fungal infection during initial hospital stay (8 days or longer). (Studies that were primarily designed to assess the effect of IVIG on humoral immune markers were excluded as were studies in which the follow-up period was one week or less). 4) At least one of the following outcomes was reported: sepsis, any serious infection, death from all causes, death from infection, length of hospital stay, intraventricular haemorrhage (IVH), necrotizing enterocolitis (NEC), bronchopulmonary dysplasia (BPD). DATA COLLECTION AND ANALYSIS: Two reviewers independently abstracted information for each outcome reported in each study, and one researcher (AO) checked for any discrepancies and pooled the results. Relative risk (RR) and Risk Difference (RD) with 95% confidence intervals (CI) using the fixed effects model are reported. When a statistically significant RD was found the number needed to treat (NNT) was also calculated with 95% CIs. The results include all accepted studies in which the outcome of interest was reported. When statistically significant heterogeneity was found for an outcome, secondary (sensitivity) analyses were performed including only studies of the highest quality. MAIN RESULTS: Fifteen studies met inclusion criteria. These included 5,054 preterm and/or LBW infants and reported on at least one of the outcomes of interest for this systematic review. When all studies were combined there was a statistically significant reduction in sepsis, one or more episodes [RR 0.83 (95% CI 0.72, 0.97); RD -0.028 (95% CI -0.006, -0.051); NNT 36 (95% CI 20, 167)]. There was significant between-study heterogeneity. When, in a sensitivity analysis, the high quality studies were combined, the results remained significant [RR 0.78 (95% CI 0.62, 0.98); RD -0.031(95% CI -0.003, -0.059); NNT 32 (95% CI 17, 333]. For this analysis there was no statistically significant between-study heterogeneity. A statistically significant reduction was also found for any serious infection, one or more episodes, when all studies were combined [RR 0.85 (95% CI 0.75, 0. 95); RD -0.032 (95% CI -0.010, -0.054,); NNT 31 (95% CI 19, 100). There was statistically significant between-study heterogeneity. When, in a sensitivity analysis, the high quality studies were combined the results remained statistically significant [RR 0.80 (95% CI

Cross Infection↗