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PubMed2003

Ibuprofen for the treatment of a patent ductus arteriosus in preterm and/or low birth weight infants.

BACKGROUND: A patent ductus arteriosus (PDA) complicates the clinical course of preterm infants, increasing their risks of developing chronic lung disease (CLD), necrotizing enterocolitis (NEC), and intraventricular hemorrhage (IVH). Indomethacin is used as standard therapy to close a PDA, but is associated with reduced blood flow to the brain, kidneys and gut. Ibuprofen, another cyclo-oxygenase inhibitor, may be as effective with fewer side effects. OBJECTIVES: To determine the effectiveness and safety of ibuprofen compared to placebo or no intervention for closing a PDA in preterm and/or low birth weight infants. To determine the effectiveness and safety of ibuprofen compared to other cyclo-oxygenase inhibitors (including indomethacin, mefenamic acid) for closing a PDA in preterm and/or low birth weight infants. SEARCH STRATEGY: Randomized (or quasi-randomized) controlled trials (RCTs) comparing ibuprofen to placebo or indomethacin or mefenamic acid for therapy of PDA were identified by searching the Cochrane Controlled Trials Register (Issue 4, 2002), MEDLINE (1996 - January 2003), CINAHL (1982 - November 2002), EMBASE (1980 - January 2002), reference lists of published RCTs and abstracts from the Pediatric Academic Societies and the European Society for Pediatric Research meetings published in Pediatric Research (1991 - 2002). No language restrictions were applied. SELECTION CRITERIA: 1) DESIGN: Randomized or quasi-randomized controlled trials 2) POPULATION: Preterm (< 37 weeks gestational age) or low birth weight infants (< 2500 grams) with a clinically or echocardiographically diagnosed PDA 3) INTERVENTION: Administration of ibuprofen for the closure of PDA 4) OUTCOMES: At least one of the following outcomes were reported: failure to close a PDA, mortality, surgical ligation, intraventricular haemorrhage (IVH), periventricular leukomalacia (PVL), NEC, decreased urine output, retinopathy of prematurity (ROP), CLD, sepsis, days on supplementary oxygen. DATA COLLECTION AND ANALYSIS: At least two reviewers worked independently at each step of the review, then compared results and resolved differences. Methodological quality of eligible studies was assessed according to blinding of randomization, of intervention and of outcome assessment, and completeness of followup. Weighted treatment effects, calculated using Revman 4.1, included typical relative risk (RR), typical risk difference (RD), number needed to treat (NNT) or harm (NNH), and weighted mean difference (WMD), all with 95% confidence intervals (CI). A fixed effect model was used for meta-analyses. Heterogeneity tests were performed to assess the appropriateness of pooling the data. MAIN RESULTS: Eight studies including 509 patients were included. All studies compared the effectiveness of ibuprofen to indomethacin for the closure of a PDA. There was no statistically significant heterogeneity of treatment effect for any of the outcomes. For the primary outcome (failure of ductal closure), there was no statistically significant difference between ibuprofen and indomethacin groups [RR 0.92 (95% CI 0.69, 1.22)]. There were no statistically significant differences in mortality, surgical duct ligation, duration of ventilator support, IVH, PVL, NEC, time to full enteral feeds, ROP, sepsis, duration of hospital stay or gastrointestinal bleed. For many of these outcomes the sample size was small and the estimates imprecise. The incidence of decreased urine output (< 1cc/kg/hr) was lower in the ibuprofen group as compared to the indomethacin group [NNT 9 (95% CI 5-14)]. This was the only statistically significant clinical finding favouring ibuprofen. Chronic lung disease defined as oxygen requirement at 28 days post-natally was statistically significantly more likely to occur in the ibuprofen group [RR 1.37 (95% CI 1.01, 1.86); NNH 7 (95% CI 3 - 100)]. No studies comparing ibuprofen versus placebo for the closure of PDA were identified. REVIEWER'S CONCLUSIONS: We found no statistically significant difference in the effectiveness of ibuprofen compared to indomethacin in closing the PDA. Ibuprofen reduces the risk of oliguria. However, ibuprofen may increase the risk for chronic lung disease, and pulmonary hypertension has been observed in three infants after prophylactic use of ibuprofen. Based on currently available information ibuprofen does not appear to confer a net benefit over indomethacin for the treatment of a PDA. We conclude that indomethacin should remain the drug of choice for the treatment of a PDA. Future research may include a four arm trial where infants are randomized at birth, either to a prophylaxis arm starting at birth or to an arm in which treatment starts after a PDA is diagnosed by echocardiography within the first seven days of life. Within the prophylaxis and treatment arms, the infants would be randomized to either ibuprofen or indomethacin. The primary outcome should be intact survival (survival without handicap) at 18 months corrected age.

Cyclooxygenase Inhibitors↗
PubMed2005

Ibuprofen for the treatment of patent ductus arteriosus in preterm and/or low birth weight infants.

BACKGROUND: A patent ductus arteriosus (PDA) complicates the clinical course of preterm infants, increasing their risks of developing chronic lung disease (CLD), necrotizing enterocolitis (NEC), and intraventricular hemorrhage (IVH). Indomethacin is used as standard therapy to close a PDA, but is associated with reduced blood flow to the brain, kidneys and gut. Ibuprofen, another cyclo-oxygenase inhibitor, may be as effective with fewer side effects. OBJECTIVES: To determine the effectiveness and safety of ibuprofen compared to placebo or no intervention for closing a PDA in preterm and/or low birth weight infants. To determine the effectiveness and safety of ibuprofen compared to other cyclo-oxygenase inhibitors (including indomethacin, mefenamic acid) for closing a PDA in preterm and/or low birth weight infants. SEARCH STRATEGY: Randomized or quasi-randomized controlled trials (RCTs) comparing ibuprofen to placebo or indomethacin or mefenamic acid for therapy of PDA were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 2, 2005), MEDLINE (1996 - July 2005), CINAHL (1982 - July 2005), EMBASE (1980 - July 2005), reference lists of published RCTs and abstracts from the Pediatric Academic Societies and the European Society for Pediatric Research meetings published in Pediatric Research (1991 - April 2005). No language restrictions were applied. SELECTION CRITERIA: 1) DESIGN: Randomized or quasi-randomized controlled trials 2) POPULATION: Preterm (< 37 weeks gestational age) or low birth weight infants (< 2500 grams) with a clinically or echocardiographically diagnosed PDA 3) INTERVENTION: Administration of ibuprofen for the closure of PDA 4) OUTCOMES: At least one of the following outcomes were reported: failure to close a PDA, mortality, surgical ligation, intraventricular haemorrhage (IVH), periventricular leukomalacia (PVL), NEC, decreased urine output, retinopathy of prematurity (ROP), chronic lung disease (CLD), sepsis, days on supplementary oxygen. DATA COLLECTION AND ANALYSIS: At least two authors worked independently at each step of the original review, then compared results and resolved differences. The current update was conducted by one author (AO). Methodological quality of eligible studies was assessed according to blinding of randomization, of intervention and of outcome assessment, and completeness of follow up. Weighted treatment effects, calculated using RevMan 4.2, included typical relative risk (RR), typical risk difference (RD), number needed to treat (NNT) or harm (NNH), and weighted mean difference (WMD), all with 95% confidence intervals (CI). A fixed effect model was used for meta-analyses. Heterogeneity tests including I(2 )were performed to assess the appropriateness of pooling the data. MAIN RESULTS: No study using mefenamic acid was identified. One study compared ibuprofen to placebo but results were not reported unblinded to group. Eleven studies including 620 patients compared the effectiveness of ibuprofen to indomethacin for the closure of a PDA. There was no statistically significant heterogeneity of treatment effect for any of the outcomes. For the primary outcome (failure of ductal closure), there was no statistically significant difference between ibuprofen and indomethacin groups [typical RR 0.96 (95% CI 0.74, 1.25)]. There were no statistically significant differences in mortality, surgical duct ligation, duration of ventilator support, IVH, PVL, NEC, time to full enteral feeds, ROP, sepsis, duration of hospital stay or gastrointestinal bleed. For many of these outcomes the sample size was small and the estimates imprecise. The incidence of decreased urine output (< 1cc/kg/hr) was lower in the ibuprofen group as compared to the indomethacin group [NNT 9 (95% CI 5-14)]. This was the only statistically significant clinical finding favouring ibuprofen. CLD defined as oxygen requirement at 28 days post-natally was statistically significantly more likely to occur in the ibuprofen group [typical RR 1.37 (95% CI 1.01, 1.86); NNH 7 (95% CI 3 - 100)]. There was a similar trend for CLD at 36 weeks corrected gestational age. AUTHORS' CONCLUSIONS: We found no statistically significant difference in the effectiveness of ibuprofen compared to indomethacin in closing the PDA. Ibuprofen reduces the risk of oliguria. However, ibuprofen may increase the risk for CLD, and pulmonary hypertension has been observed in three infants after prophylactic use of ibuprofen. Based on currently available information ibuprofen does not appear to confer a net benefit over indomethacin for the treatment of a PDA. We conclude that indomethacin should remain the drug of choice for the treatment of a PDA. The most urgent research question to be answered is weather ibuprofen compared to indomethacin confers an improved rate of intact survival (survival without impairment) at 18 months corrected age.

Cyclooxygenase Inhibitors↗
PubMed2005

The Washington University Twin Study of alcoholism.

Genetic contributions to the liability to develop alcoholism in males of Northern and Western European ancestry are well-established. However, questions remain concerning the role of genetic variation in the etiology of alcoholism among non-white populations, among women, and the possibility of etiological heterogeneity in subtypes of alcoholism. The answers to these questions are needed to help define phenotypes for molecular genetic studies searching for QTLs for alcoholism. Twins from 295 pairs were consecutively ascertained at inpatient and outpatient psychiatric and alcohol treatment facilities in St. Louis, MO in 1981-1986. Probands and willing cotwins were evaluated by structured psychiatric interviews, psychometric assessment, and lifetime treatment records. One hundred fifty-four probands met criteria for alcohol abuse/dependence (AAD), including twins from 45 MZ, 50 same-sex DZ, and 59 opposite-sex pairs. Twin-pair resemblance was evaluated for AAD and alcohol dependence (AD), as well as for subsets defined by gender, patterns of comorbidity, ethnic background, and clinical features. Among males, heritability of AAD and AD was substantial, with little evidence for common environmental contributions to family resemblance. Pair resemblance among females was also substantial, but similar for MZ and DZ pairs, yielding near-zero heritability estimates. However, based on these sample sizes, the sex differences were not statistically significant. The results confirm prior studies of strong genetic influences on alcoholism in males, but suggest lower genetic influence in females. Power to test other sources of heterogeneity was limited, but the results suggest no evidence for higher heritability for male early onset alcoholism or for alcoholism with comorbid antisocial personality.

Adolescent↗
PubMedDate not supplied

Local histogram correction of MRI spatially dependent image pixel intensity nonuniformity.

We describe a computationally straightforward post-hoc statistical method of correcting spatially dependent image pixel intensity nonuniformity based on differences in local tissue intensity distributions. Pixel intensity domains for the various tissues of the composite image are identified and compared to the distributions of local samples. The nonuniformity correction is calculated as the difference of the local sample median from the composite sample median for the tissue class most represented by the sample. The median was chosen to reduce the effecters on determining the sample statistic and to allow a sample size small enough to accurately estimate the spatial variance of the image intensity nonuniformity. The method was designed for application to two-dimensional images. Simulations were used to estimate optimal conditions of local histogram kernel size and to test the accuracy of the method under known spatially dependent nonuniformities. The method was also applied to correct a phantom image and cerebral MRIs from 15 healthy subjects. Results show that the method accurately models simulated spatially dependent image intensity differences. Further analysis of clinical MR data showed that the variance of pixel intensities within the cerebral MRI slices and the variance of slice volumes within individuals were significantly reduced after nonuniformity correction. Improved brain-cerebrospinal fluid segmentation was also obtained. The method significantly reduced the variance of slice volumes within individuals, whether it was applied to the native images or images edited to remove nonbrain tissues. This statistical method was well behaved under the assumptions and the images tested. The general utility of the method was not determined, but conditions for testing the method under a variety of imaging sequences is discussed. We believe that this algorithm can serve as a method for improving MR image segmentation for clinical and research applications.

Adult↗
PubMed2006

A sequential design to estimate sensitivity and specificity of a diagnostic or screening test.

We consider efficient study designs to estimate sensitivity and specificity of a candidate diagnostic or screening test. Our focus is the setting in which the candidate test is inexpensive to administer compared to evaluation of disease status, and the test results, available in a large cohort, can be used as a basis for sampling subjects for verification of disease status. We examine designs in which disease status is verified in a sample chosen so as to optimize estimation of either sensitivity or specificity. We then propose a sequential design in which the first step of sampling is conducted to efficiently estimate specificity. If the candidate test is determined to be of sufficient specificity, then step two of sampling is conducted to estimate sensitivity. We propose estimators based on this sequential sampling scheme, and show that the performance of these estimators is excellent. We develop sample size calculations for the sequential design, and show that this design, in most situations, compares favourably in terms of expected sample size to a fixed size design.

Biometry↗
PubMedDate not supplied

Bias correction in maximum likelihood logistic regression.

This paper provides an expression for bias of the maximum likelihood logistic regression estimates for use with small sample sizes. This bias correction is based on an expansion of the maximum likelihood equation. Simulation results show these corrections to be highly effective in small samples.

Probability↗
PubMed1993

Automated ribosomal DNA fingerprinting by capillary electrophoresis of PCR products.

Capillary electrophoresis (CE) provides a rapid and automated technique for the analysis of subnanogram amounts of DNA fragments generated by the polymerase chain reaction (PCR). Here we describe the implementation of size-selective CE for DNA profiling and restriction fragment length polymorphism analysis of amplified polymorphic spacers of ribosomal DNA from fungi. Separations of unpurified and isopropanol-precipitated PCR-amplified DNA fragments in the size range of 20-1600 base pairs were achieved in less than 20 min with the use of hydroxypropyl methylcellulose as a sieving medium. The amplified internal transcribed spacer (ITS) and intergenic spacer (IGS) of RNA genes could be sized by coelectrophoresing a standard size ladder mixed with every sample, thereby eliminating errors in size estimation. This, together with the strictly controlled conditions of CE, permit the discrimination of amplified rDNA fragments differing only a few base pairs in length. Inter- and intraspecific variation in the size and number of restriction sites of the amplified rDNA spacers from the ectomycorrhizal basidiomycetes Laccaria laccata and Laccaria bicolor was observed and most strains could thus be reliably genotyped by PCR-CE. Multiple amplified IGS fragments of heterogeneous size were detected in several strains. This polymorphism is due to the occurrence of 5S rDNA subrepeats (i.e., multiple annealing of primer) within IGS. With CE, in contrast to slab gel electrophoresis, run times are short, the capillary can be reused, and full automation is feasible. Data acquisition and analysis are computer-controlled, which facilitates the locus identification and reduces error especially when large numbers of PCR products must be analyzed.(ABSTRACT TRUNCATED AT 250 WORDS)

Autoanalysis↗
PubMed1983

A new method for the topological analysis of neuronal tree structures.

Statistical analysis of the frequencies of observed branching patterns of neuronal arborescences is an important means of studying neuronal growth and of characterizing axonal or dendritic populations. We recently derived simple formulae for the exact probabilities of occurrence of types of neuronal trees for both segmental and terminal growth. Additionally, the existence of a natural ordering of the neuronal tree types enables the application of the Kolmogorov goodness-of-fit test. In the present report it is illustrated how these facilities can be incorporated in the analysis of neuronal arborizations. Interesting features are that very large neuronal arborizations can be analyzed completely and that only small sample sizes are required for the estimation of the critical level corresponding to the growth hypothesis. Further, it is indicated how populations of neuronal tree structures may be compared with each other without reference to a particular growth theory.

Animals↗
PubMed2005

A group sequential adaptive treatment assignment design for proof of concept and dose selection in headache trials.

The trial objective was to test whether a new mechanism of action would effectively treat migraine headaches and to select a dose range for further investigation. The motivation for a group sequential, adaptive, placebo-controlled trial design was (1) limited information about where across the range of seven doses to focus attention, (2) a need to limit sample size for a complicated inpatient treatment and (3) a desire to reduce exposure of patients to ineffective treatment. A design based on group sequential and up and down designs was developed and operational characteristics were explored by trial simulation. The primary outcome was headache response at 2 h after treatment. Groups of four treated and two placebo patients were assigned to one dose. Adaptive dose selection was based on response rates of 60% seen with other migraine treatments. If more than 60% of treated patients responded, then the next dose was the next lower dose; otherwise, the dose was increased. A stopping rule of at least five groups at the target dose and at least four groups at that dose with more than 60% response was developed to ensure that a selected dose would be statistically significantly (p=0.05) superior to placebo. Simulations indicated good characteristics in terms of control of type 1 error, sufficient power, modest expected sample size and modest bias in estimation. The trial design is attractive for phase 2 clinical trials when response is acute and simple, ideally binary, placebo comparator is required, and patient accrual is relatively slow allowing for the collection and processing of results as a basis for the adaptive assignment of patients to dose groups. The acute migraine trial based on this design was successful in both proof of concept and dose range selection.

Clinical Trials, Phase II as Topic↗
PubMedDate not supplied

[Quality perceived by outpatients at the pharmaceutical care clinic].

OBJECTIVE: To know the satisfaction degree manifested by outpatients presenting in the hospital pharmacy department pharmaceutical care clinic, and to identify organizational improvement items. METHOD: A survey with 8 close-ended questions and 1 open-ended question was designed where patients recorded their suggestions or comments on the service provided. A sample size of 591 surveys was estimated, which allowed to estimate parameters of interest with a 95% confidence interval and a +/- 5% accuracy, adjusting by a 40% potential losses percentage. RESULTS: Overall response rate was 70%; 23.6% of patients considered that finding the PD was difficult or very difficult. Waiting time was normal for 51.8%, but long or excessive for 18.4% of patients. Fifty-six percent of individuals considered the information received useful or very useful, and 81.1% considered that staff friendliness was good or very good. Care timetable was inadequate for 18.1%; 47.7% pointed out that the attending pharmacist did not identify him or herself. Overall satisfaction extent was 7.51 (of 10). A plan for improvement activities was designed and implemented regarding: care timetable, pharmacy department signaling, and general information on clinic matters. CONCLUSIONS: The survey allowed to identify organizational weaknesses. Overall score was very satisfactory, yet improvable. Future surveys are required for result comparisons and continual improvement assessment.

Adolescent↗
PubMed1994

Analysis of multiple-dose bioequivalence studies.

In multiple-dose bioequivalence studies, it is possible at steady state to take repeated measurements of pharmacokinetic variables, such as area under the curve (AUC) and the maximum concentration (CMAX) of the blood concentration-time profile, within each period of a crossover design. We develop a bivariate random effects model for such a situation in a 2 x 2 crossover design using the natural log scale for AUC and CMAX that assumes no differential carryover effects and includes components for inter- and intrasubject variability with respect to both formulations. We derive the uniformly minimum variance unbiased estimators, which also happen to be restricted maximum likelihood estimators, and we provide a sample size formula.

Cross-Over Studies↗
PubMed1983

Optimal design of the chronic animal bioassay.

Optimal experimental designs for carcinogenicity bioassays conducted for the assessment of risks associated with exposure to environmental chemicals are derived. For our purposes, an optimal experimental design is a design that minimizes the mean-squared error of the maximum likelihood estimate of the virtually safe dose from the Armitage-Doll multistage model and maintains a high power for the detection of increased carcinogenic response. Three- and four-dose designs (including control as one of the doses) are discussed for a variety of dose response patterns. Monte Carlo simulation techniques are used to estimate the power and mean-squared error for small samples sizes. Two forms of the multistage model are used to estimate the virtually safe dose: the linear model and the linear-quadratic model. The optimal designs for fitting the linear model used a control group and a group administered the maximum tolerated dose, with about 50% of the animals at each dose. The three- and four-dose optimal designs when fitting the linear-quadratic model were found to be equivalent. However, after considering several biological issues, including overt toxicity, the optimal four-dose designs would use between 150 and 300 animals, with 50 to 60 animals in the control group, and 40 to 60 animals in the group administered the maximum tolerated dose. One-third of the remaining animals would be administered a dose between 10 and 30% of the maximum tolerated dose, and two-thirds of the remaining animals would be administered 50% of the maximum tolerated dose.

Animals↗
PubMed2001

Complexity and power in case-control association studies.

A general method is described for estimation of the power and sample size of studies relating a dichotomous phenotype to multiple interacting loci and environmental covariates. Either a simple case-control design or more complex stratified sampling may be used. The method can be used to design individual studies, to evaluate the power of alternative test statistics for complex traits, and to examine general questions of study design through explicit scenarios. The method is used here to study how the power of association tests is affected by problems of allelic heterogeneity and to investigate the potential role for collective testing of sets of related candidate genes in the presence of locus heterogeneity. The results indicate that allele-discovery efforts are crucial and that omnibus tests or collective testing of alleles can be substantially more powerful than separate testing of individual allelic variants. Joint testing of multiple candidate loci can also dramatically improve power, despite model misspecification and inclusion of irrelevant loci, but requires an a priori hypothesis defining the set of loci to investigate.

Alleles↗
PubMed1996

Body mass index in screening for adiposity in children and adolescents: systematic evaluation using receiver operating characteristic curves.

Body mass index (BMI) has been recommended for use in adolescent screening programs to select subjects with excess body fat for appropriate interventions. No systematic evaluation of MBI in screening for high degrees of adiposity was available when these recommendations were formulated. The purpose of this paper was to evaluated the screening performance of BMI using appropriate epidemiologic methods. Percentage body fat (TBF%) was measured by dual-energy X-ray absorptiometry DXA) in a convenience sample of 230 (119 males, 111 females) health Australian volunteers aged 4-20 y inclusive. Receiver operating characteristic (ROC) curves were prepared for detecting TBF% at or beyond the 85th percentile, using BMI as the screening test. Screening performance was slightly better for girls than for boys, but the differences were not significant. Reasonable true-positive (0.71, 95% CI: 0.53, 0.85) and low false-positive (0.05, 95% CI: 0.02, 0.09) rates were observed at the 85th percentile cutpoint for BMI. At the 95th percentile cutpoint for BMI, both true-positive (0.29, 95% CI: 0.15, 0.47) and false-positive (0.01, 95% CI: 0.00, 0.03) rates were lower. Screening for excess adiposity by using an appropriate percentile cutoff for BMI gives acceptable performance. ROC curves facilitate design of screening programs by allowing an explicit tradeoff between true-positive and false-positive rates. Although large sample sizes are required for precise estimates, the cutoff points that have been recommended appear to offer a reasonable compromise between true-and false-positive rates.

Absorptiometry, Photon↗
PubMed1989

Statistical method for testing the neutral mutation hypothesis by DNA polymorphism.

The relationship between the two estimates of genetic variation at the DNA level, namely the number of segregating sites and the average number of nucleotide differences estimated from pairwise comparison, is investigated. It is found that the correlation between these two estimates is large when the sample size is small, and decreases slowly as the sample size increases. Using the relationship obtained, a statistical method for testing the neutral mutation hypothesis is developed. This method needs only the data of DNA polymorphism, namely the genetic variation within population at the DNA level. A simple method of computer simulation, that was used in order to obtain the distribution of a new statistic developed, is also presented. Applying this statistical method to the five regions of DNA sequences in Drosophila melanogaster, it is found that large insertion/deletion (greater than 100 bp) is deleterious. It is suggested that the natural selection against large insertion/deletion is so weak that a large amount of variation is maintained in a population.

Animals↗
PubMed1983

Estimating attributable risk from case-control studies.

Levin's measure of attributable risk is extended to account for confounding. Maximum likelihood estimates and confidence intervals for this extended measure are presented. The estimates and confidence intervals apply both to matched and to stratified case-control studies. The statistical methods are illustrated by the use of data from a study of factors of womanhood as related to breast cancer, and data from a study of cigarette smoking as related to bladder cancer. The results of computer simulations are used to describe the behavior of the estimates and confidence intervals when sample size is small relative to the number of strata of the confounding factor.

Adult↗
PubMed1996

Increasing physical activity: a quantitative synthesis.

National policy for increasing leisure physical activity in the United States is impeded by a poor understanding of interventions that can be implemented by community and clinical medicine. To clarify the literature in this area, we conducted a quantitative, meta analysis of 127 studies that examined the efficacy of interventions for increasing physical activity among approximately 131,000 subjects in community, worksite, school, home, and health care settings; 445 effects were expressed as a Pearson correlation coefficient (r) and examined as they varied according to moderating variables important for community and clinical intervention. The mean effect was moderately large, r = 0.34, approximating three-fourths of a standard deviation or an increase in binomial success rate from 50% to 67%. The estimated population effect weighted by sample size was larger, r = 0.75, approximating 2 standard deviations or increased success to 88%. Contrasts between levels of independent moderating variables indicated that effects weighted by sample size were larger when the interventions: 1) employed the principles of behavior modification, 2) used a mediated delivery, 3) targeted groups, 4) of combined ages, 5) sampled apparently healthy people, or 6) measured active leisure, of 7) low intensity, 8) by observation. Independently of sample size, effects were larger when interventions 1) used behavior modification, 2) employed a preor quasi-experimental design, or 3) were of short duration, regardless of features of the people, setting, or physical activity. Our results show that physical activity can be increased by intervention. The optimal ways for selecting intervention components, settings, and population segments to maintain increases in physical activity and the relative contributions by community and clinical medicine toward successful physical activity intervention require experimental confirmation, warranting accelerated attention in clinical trials.

Exercise↗
PubMed2006

A randomized controlled equivalence trial of short-term complications and efficacy of tension-free vaginal tape and suprapubic urethral support sling for treating stress incontinence.

OBJECTIVE: To establish the equivalence between the tension-free vaginal tape (TVT) and the suprapubic urethral support sling (SPARC). Approximately 35% of women have stress urinary incontinence (SUI), and although TVT is now perceived as the standard treatment, the SPARC is a very similar procedure and is thought to have fewer peri-operative complications. PATIENTS AND METHODS: Patients with clinical SUI were recruited from public and private urology/urogynaecology clinics, and participated in the trial of TVT vs SPARC. The primary outcome was bladder perforation; secondary outcomes were blood loss, voiding difficulty, urgency, and cure of SUI symptoms. Sample size calculations, based on an estimated 2% perforation rate, showed that 290 patients would be needed to detect a clinically significant difference of 5%. Stratification was by previous incontinence surgery and the experience of the surgeon. RESULTS: There were 301 operations; the difference in bladder perforations was not statistically significant, at one/147 TVT (0.7%), and three/154 SPARC (1.9%), with the difference in rate of 0.013 (95% confidence interval (CI) - 0.01 to 0.04; odds ratio 2.89, 95% CI 0.30-28.21; P = 0.62), and nor were differences in estimated blood loss of >100 mL (TVT, 32/147, 21.8%; SPARC 28/154, 18.2%); de novo urgency (TVT 15/37, 40.5%; SPARC 14/33, 42.4%), objective cure (TVT 143/147, 97.3%; SPARC 148/152, 97.4%) or vaginal mesh erosion (TVT 7/147, 4.8%; SPARC 16/152, 10.5%). Acute urinary retention (TVT none of 147; SPARC 10/154, 6.5%; odds ratio infinity, 95% CI 2.2-infinity; P = 0.002) and subjective cure (TVT 128/147, 87.1%; SPARC 117/153, 76.5%; odds ratio 2.07, 95% CI 1.13-3.81; P = 0.03) were statistically significantly different. CONCLUSION: These results are consistent with clinical equivalence between TVT and SPARC for bladder perforation. There was no statistically significant difference between TVT and SPARC in blood loss, urgency or objective cure of SUI symptoms at 6 weeks. However, SPARC was more difficult to adjust correctly, and a statistically significant number of patients required loosening of the tape in theatre (P = 0.002). TVT had a lower rate of vaginal erosion and a statistically significantly higher cure rate of subjective SUI symptoms than SPARC. Overall, voiding difficulty (loosening of the tape), urgency and vaginal mesh erosion were the most important clinical problems. This trial showed the importance of testing new devices which appear to be similar, but which might have relevant differences. There was no financial assistance for this study, and a long-term follow up is planned.

Adult↗