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PubMed1993

Evaluating interventions with differential attrition: the importance of nonresponse mechanisms and use of follow-up data.

Evaluations of psychological interventions are often criticized because of differential attrition, which is cited as a severe threat to validity. The present study shows that differential attrition is not a problem unless the mechanism causing the attrition is inaccessible (unavailable for analysis). With a simulation study, we show that conclusions about program effects (a) are unbiased when there is no differential attrition, even with usual complete cases analysis; (b) may be severely biased when based on usual complete cases analyses and there is differential attrition; (c) are unbiased when based on the expectation-maximization (EM) algorithm, even when there is differential attrition, as long as the attrition mechanism is accessible; and (d) are biased, even with the EM algorithm, when the attrition mechanism is inaccessible. Following Little and Rubin (1987), we advocate the collection of new data from a random sample of subjects with initially missing data. On the basis of these data, we propose a simple correction to the EM algorithm estimates. In our study, the correction produced unbiased estimates of program effects parameters, even with an inaccessible attrition mechanism and substantial differential attrition.

Bias↗
PubMed1997

Free-living energy expenditure of adult men assessed by continuous heart-rate monitoring and doubly-labelled water.

Free-living energy expenditure was estimated by doubly-labelled water (DLW) and continuous heart-rate (HR) monitoring over nine consecutive days in nine healthy men with sedentary occupations but different levels of leisure-time physical activity. Individual calibrations of the HR-energy expenditure (EE) relationship were obtained for each subject using 30 min average values of HR and EE obtained during 24 h whole-body calorimetry with a defined exercise protocol, and additional data points for individual leisure activities measured with an Oxylog portable O2 consumption meter. The HR data were processed to remove spurious values and insert missing data before the calculation of EE from second-order polynomial equations relating EE to HR. After data processing, the HR-derived EE for this group of subjects was on average 0.8 (SEM 0.6) MJ/d, or 6.0 (SEM 4.2) % higher than that estimated by DLW. The diary-respirometer method, used over the same 9 d, gave values which were 1.9 (SEM 0.7) MJ/d, or -12.1 (SEM 4.0) % lower than the DLW method. The results suggest that HR monitoring can provide a better estimate of 24 h EE of groups than the diary-respirometer method, but show that both methods can introduce errors of 20% or more in individuals.

Adult↗
PubMed1995

Issues in incorporation semantic integrity in molecular biological object-oriented databases.

Issues critical to ensuring semantic integrity in molecular biological data collections have been identified and include complexity, exceptions, missing data, changing models, holism and integration, delocalized data, interoperability and nomenclature. This combination is peculiar to biology and presents some interesting problems as a result. Little is known about semantic checking in object-oriented databases in general, but because such technology appears highly suitable for modeling biological data, it is appropriate to examine the ways in which object-oriented technology can support this functionality. It is concluded that object-oriented technology will support semantic checking even in a complex domain like biology. We propose 10 guidelines for future work including ways of treating exceptional cases and 'positioning' of constraints in a schema.

Biotechnology↗
PubMed1996

Admission base deficit predicts transfusion requirements and risk of complications.

BACKGROUND: Trauma center resource management could be facilitated by a readily available indicator of resource consumption. This marker should identify patients more likely to require transfusion and intensive care services and to develop complications. Base deficit (BD) has been shown to be a valuable indicator of shock, abdominal injury, fluid requirements, efficacy of resuscitation, and to be predictive of mortality after trauma. This study was performed to determine whether BD could be used to identify which patients were likely to require blood transfusion in the first 24 hours of hospitalization, and to develop shock-related complications and increased intensive care unit (ICU) and hospital stays. METHODS: A retrospective review of 2,954 patients admitted to the Valley Medical Center Level I trauma service from July 1990 through August 1995 was done using the trauma registry and blood bank data bases. Medical record review was done to supplement missing data. RESULTS: Transfusion requirements increased as the BD category became more severe (p < 0.001). Transfusions were required within 24 hours of admission in 72% of patients with a BD < or = -6 versus 18% of patients with a BD > -6 (p < 0.001, chi 2). Both ICU and hospital length of stay increased with worsening BD (p < 0.015 and p < 0.05, respectively). The frequency of adult respiratory distress syndrome (ARDS) (p < 0.01), renal failure (p = 0.015), coagulopathy (p < 0.001), and multiorgan system failure (MOF) (p = 0.002) all increased with increasingly severe BD. Discriminate analysis using Injury Severity Score (ISS) and BD category demonstrated predictive accuracy of 81%, 77%, and 77% for coagulopathy, ARDS, and MOF, respectively. Mortality also increased with worsening BD. When stratified by BD category, there was no difference between observed and predicted survival. CONCLUSIONS: Admission BD identifies patients likely to require early transfusion and increased ICU and hospital stays, and be at increased risk for shock-related complications. Patients with BD < or = -6 should undergo type and cross-match rather than type and screen. The use of ISS and BD category probability curves may identify candidates for early invasive monitoring.

Acid-Base Imbalance↗
PubMed2004

Underestimation of standard errors in multi-site time series studies.

Multi-site time series studies of the association of air pollution with mortality and morbidity have figured prominently in the literature as comprehensive approaches for estimating short-term effects of air pollution on health. Hierarchical models are generally used to combine site-specific information and to estimate pooled air pollution effects while taking into account both within-site statistical uncertainty and across-site heterogeneity. Within a site, characteristics of time series data of air pollution and health (small pollution effects, missing data, and highly correlated predictors) make the modeling of all sources of uncertainty challenging. One potential consequence is underestimation of the statistical variance of the site-specific effects to be combined.In this paper, we investigate the impact of variance underestimation on the pooled relative rate estimate. We focused on two-stage normal-normal hierarchical models and on underestimation of the statistical variance at the first stage. By mathematical considerations and simulation studies, we found that variance underestimation did not affect the pooled estimate substantially. However, the pooled estimate was somewhat sensitive to variance underestimation when the number of sites was small and underestimation was severe. These simulation results are applicable to any two-stage normal-normal hierarchical model for combining information of site-specific results (including meta-analyses), and they can easily be extended to more general hierarchical formulations. We also examined the impact of variance underestimation on the national average relative rate estimate from the National Morbidity, Mortality and Air Pollution Study. We found that variance underestimation as large as 40% had little effect on the national average.

Air Pollutants↗
PubMedDate not supplied

On summary measures analysis of the linear mixed effects model for repeated measures when data are not missing completely at random.

Subjects often drop out of longitudinal studies prematurely, yielding unbalanced data with unequal numbers of measures for each subject. A simple and convenient approach to analysis is to develop summary measures for each individual and then regress the summary measures on between-subject covariates. We examine properties of this approach in the context of the linear mixed effects model when the data are not missing completely at random, in the sense that drop-out depends on the values of the repeated measures after conditioning on fixed covariates. The approach is compared with likelihood-based approaches that model the vector of repeated measures for each individual. Methods are compared by simulation for the case where repeated measures over time are linear and can be summarized by a slope and intercept for each individual. Our simulations suggest that summary measures analysis based on the slopes alone is comparable to full maximum likelihood when the data are missing completely at random but is markedly inferior when the data are not missing completely at random. Analysis discarding the incomplete cases is even worse, with large biases and very poor confidence coverage.

Computer Simulation↗
PubMed2006

The Hardman index in patients operated on for ruptured abdominal aortic aneurysm: A systematic review.

BACKGROUND: The aims of the present study were to (1) analyze preoperative predictors for outcome suggested by Hardman and surgical mortality after open repair and endovascular repair (EVAR) of ruptured abdominal aortic aneurysms (rAAA), and (2) further evaluate the Hardman index in a systematic review. METHODS: Patients operated on for rAAA during a 5-year period between 2000 and 2004 were scored according to Hardman-1 point for either age >76 years, loss of consciousness after presentation, hemoglobin <90 g/L, serum creatinine >190 micromol/L or electrocardiographic (ECG) signs of ischemia-with blinded evaluation of ECGs by a specialist in clinical physiology. The results were included in a systematic review of studies evaluating the Hardman index. RESULTS: In-hospital mortality after operation was 41% (67/162). There was no difference in in-hospital mortality between open repair (n = 106) and EVAR (n = 56), whereas the Hardman index was associated with operative mortality in our institution and in the systematic review of 970 patients (P < .001). Mortality rate in patients with Hardman index > or =3 was 77% in the pooled analysis. A full data set of all five scoring variables was obtained in 94 (58%) of 162 patients in our study, and potential underscoring was thus possible in 68 patients. Of the available ECGs, 12 (8.7%) of 138 were judged nondiagnostic. Five studies did not state their missing data on ECG and hemoglobin and serum creatinine concentrations, nor did they specify the criteria for ECG ischemia. CONCLUSIONS: A strong correlation between the Hardman index and mortality was found. A Hardman index > or =3 cannot be used as an absolute limit for denial of surgery. The utility of the Hardman index seems to be impeded by variability in scoring resulting from missing or nondiagnostic data.

Aneurysm, Ruptured↗
PubMed2003

Quality of recording of data from patients with type 2 diabetes is not a valid indicator of quality of care. A cross-sectional study.

BACKGROUND: The quality of recording of clinical data in diabetes care in general practices is very variable. It has been suggested that better recording leads to improved glycaemic control. OBJECTIVES: The purpose of this study was to assess the completeness of recording by GPs of data from type 2 diabetes patients; to compare recorded and missing data; and to investigate the association between completeness and glycaemic control. METHODS: A cross-sectional survey was carried out in 52 general practices. Medical records were scrutinized for the presence of 11 variables. Examining patients through an active approach completed incomplete records. We compared recorded and unrecorded items. Completeness of recording was determined at both patient and practice levels. RESULTS: Fifty-two general practices with 1641 type 2 diabetes patients cared for by the GP participated. The frequency of absence of any particular item ranged from 20 to 70%. Weight, systolic blood pressure and HbA(1c) were slightly lower in patients with those items missing on their files, and more such patients were non-smokers (P < 0.05). The percentage of patients with unrecorded variables that exceeded target values ranged from 39 to 75. Neither at practice level nor at patient level was any association between the completeness of the data recording and HbA(1c) found. CONCLUSION: Records often were incomplete, which hampers a systematic approach to care of diabetic patients. However, the lack of association between completeness of data recording and control of glycaemia indicates that improved recording is not a valid indicator of good quality of care.

Adult↗
PubMed2005

Patterns and time of initiation of dialysis in US children.

The purpose of this communication is to study the clinical patterns and level of residual renal function at the initiation of dialysis in children in the United States of America (US). Data were reviewed for 7,039 children under the age of 20 years and 647,600 adults extracted from the patient incidence report, obtained from the United States Renal Data Systems (USRDS), who were initiated on dialysis between January 1995 and September 2002. Based on pre-defined exclusion criteria, only 4,808 of the 7,093 (67.8%) pediatric entries were included in the analysis. About 6.9% of the entries were not used because of missing data only, 23.3% because of out of range data only, and 2.0% because of both missing and out of range data, a total of 32.2% exclusions. For adults, 570,808 (88.1%) had acceptable data. The percentage of the 4,808 children who were initiated on dialysis with an estimated GFR greater than 10 mL min(-1) per 1.73 m(2) (early start) was 49.6%. Using logistic regression, the factors affecting the probability of an early start were sex, race, type of insurance, region of the country, age at initiation of dialysis, and the year dialysis was initiated. The highest chance of starting dialysis early (0.77) was for a white male, aged 15-19 years, with insurance and residing in the Northwest part of the US The percentage of 4,808 children who initiated dialysis with an estimated GFR less than 5 mL min(-1) per 1.73 m(2) (late start) was 7.3%. The factors affecting the probability of a late start were sex, race, type of insurance, and the year dialysis was initiated. The greatest chance for a late start of dialysis was for black female patients without insurance (0.21). Mean estimated GFR at the start of dialysis was higher for children than for adults (10.7+/-4.6 vs 8.2+/-4.1 mL min(-1) per 1.73 m(2), respectively, P<0.0001). It was concluded that patterns of management of children with ESRD are not uniform among US children.

Adolescent↗
PubMed2006

Dermatology residency program characteristics that correlate with graduates selecting an academic dermatology career.

OBJECTIVE: To examine the characteristics of 107 dermatology residency programs to determine which factors are correlated with producing academic dermatologists to help reverse the trend of a growing shortage of academic dermatologists. DESIGN: We collected data ranging from total publications to grant funding. Extensive Internet searches were completed to obtain most of the data. Individual programs were contacted as needed to obtain any missing data that were not found on the program's Web site. SETTING: Dermatology residency programs (departments and divisions) in the United States. MAIN OUTCOME MEASURES: Factors that correlated with producing full-time academic dermatologists. RESULTS: We tabulated and analyzed characteristics of 107 dermatology residency programs. Total full-time faculty members in 2004, total publications in 2004, and total publications from January 1, 2001, to December 31, 2004, were the 3 factors most strongly correlated with producing full-time faculty. National Institutes of Health and Dermatology Foundation grants and American Skin Association grant recipients were the 3 characteristics most strongly inversely correlated with producing full-time faculty. Those who entered academic dermatology tended to stay at the same program where they completed a dermatology residency, especially if this program was considered a "smaller" program. CONCLUSIONS: The programs' characteristics of total publications in 2004 and from 2001 to 2004 were 2 of the 3 factors most strongly positively correlated with dermatology residents entering academic dermatology. Encouraging residents to publish may be a window to motivate them toward a career in academic dermatology.

Career Choice↗
PubMed2000

Stripping/sweeping the membranes for inducing labour or preventing post-term pregnancy.

BACKGROUND: Stripping or sweeping of the membranes aims to initiate labour through a cascade of physiological events. These may reduce pregnancy duration or pre-empt formal induction of labour with either oxytocin, prostaglandins or amniotomy. OBJECTIVES: The objective of this review was to assess the effects of membrane sweeping to promote or induce labour on maternal and perinatal outcomes. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register (last searched April 1998). SELECTION CRITERIA: Adequately controlled trials of digital separation of the membranes from the lower uterine segment for inducing labour or for preventing post-term pregnancy, compared to either no vaginal examination or vaginal examination for cervical assessment only without the intention to detach the membranes. DATA COLLECTION AND ANALYSIS: Two reviewers assessed trial quality and extracted data. MAIN RESULTS: Fourteen trials were included. Sweeping of the membranes, performed as a general policy in women at term, was associated with reduced duration of pregnancy and the frequency of pregnancy continuing beyond 41 weeks (relative risk 0.42, 95% confidence interval 0.19 to 0.93, random effects model) and 42 weeks. After sweeping of the membranes, there was a 17% risk reduction (confidence interval 6 to 29%, random effects model) in the use of more formal methods for labour induction. There was no difference in the mode of delivery or in the risk of infection. Discomfort during vaginal examination and other adverse effects (bleeding, irregular contractions) were more frequently reported by women allocated to sweeping. REVIEWER'S CONCLUSIONS: Routine use of sweeping of membranes from 38 weeks of pregnancy onwards does not seem to produce clinically important benefits. When used as a means for induction of labour, the reduction in the use of more formal methods of induction needs to be balanced against women's discomfort and other adverse effects.

Extraembryonic Membranes↗
PubMed2001

Mechanical methods for induction of labour.

BACKGROUND: Mechanical methods were the first methods developed to ripen the cervix or to induce labour. Devices which were used include various type of catheters and of laminaria tents, introduced into the cervical canal or into the extra-amniotic space. Mechanical methods were never completely abandoned, but were substituted by pharmacological methods during recent decades. Potential advantages of mechanical methods, compared with pharmacological methods, may include simplicity of preservation, lower cost and reduction of the side effects. However, special attention should be paid to contraindications (e.g. low-lying placenta), risk of infection and maternal discomfort when inserting these devices. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. OBJECTIVES: To determine the effects of mechanical methods for third trimester cervical ripening or induction of labour in comparison with placebo/no treatment, prostaglandins (vaginal, intracervical, misoprostol) and oxytocin. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group Trials Register, the Cochrane Controlled Trials Register and bibliographies of relevant papers. Last searched April 2001. SELECTION CRITERIA: The criteria for inclusion were the following: (1) clinical trials comparing mechanical methods used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods; (2) random allocation to the treatment or control group; (3) adequate or unclear method for allocation concealment; (4) violations of allocated management not sufficient to materially affect conclusions; (5) clinically meaningful outcome measures reported; (6) data available for analysis according to the random allocation; (7) missing data insufficient to materially affect the conclusions. DATA COLLECTION AND ANALYSIS: A strategy has been developed to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction. The initial data extraction was done centrally, and incorporated into a series of primary reviews arranged by methods of induction of labour, following a standardised methodology. The data will be extracted from the primary reviews into a series of secondary reviews, arranged by category of woman. MAIN RESULTS: In total, 58 studies were considered; 45 studies have been included and 13 were excluded. Studies generally included women with unfavourable cervix and intact membranes. Comparing mechanical methods with placebo/no treatment, only one study with 48 participants reported on vaginal delivery not achieved in 24 hours (69% with mechanical methods versus 77% with placebo/no treatment; relative risk (RR) 0.90; 95% confidence interval (CI): 0.64-1.26). Hyperstimulation with fetal heart rate changes was not reported. The risk of caesarean section, reported in six studies including 416 women, was similar between groups (34%; RR 1.00; 95% CI: 0.76-1.30). There were no reported cases of severe neonatal and maternal morbidity. Comparing mechanical methods with vaginal PGE2, only one trial (109 women) reported on vaginal delivery not achieved in 24 hours (73% versus 42%; relative risk (RR) 1.74; 95% CI: 1.21-2.49). Compared with intracervical PGE2, only one trial (100 women) reported on vaginal delivery not achieved in 24 hours (68% versus 40%; relative risk (RR) 1.70; 95% CI: 1.15-2.51). Compared with with misoprostol, the effectiveness of mechanical methods was similar (34% versus 30%; relative risk (RR) 1.15; 95% CI: 0.80-1.66). The use of mechanical method reduced the risk of hyperstimulation with fetal heart rate changes when compared with prostaglandins: vaginal PGE2 (0% versus 6%; RR 0.14; 95% CI: 0.04-0.53), intracervical PGE2 (0% versus 1%; RR 0.21; 95% CI: 0.04-1.20) and misoprostol (4% versus 9%; RR 0.41; 95% CI: 0.20-0.87). There was no difference in the risk of caesarean section between mechanical methods and prostaglandins. Serious neonatal (three cases) and maternal morbidity (one case) were infrequently reported. When compared with oxytocin, use of mechanical methods reduced the risk of caesarean section (4 trials; 198 women; 17% versus 32%; RR 0.55; 95% CI: 0.33-0.91). The likelihood of vaginal delivery in 24 hours and of hyperstimulation with fetal heart rate changes was not reported. There were no reported cases of serious maternal morbidity and severe neonatal morbidity was not reported. These results are similar whatever specific mechanical method was used, except with extra-amniotic infusion. When comparing extra-amniotic infusion with any prostaglandins, women were more likely to not achieve vaginal delivery within 24 hours (57% versus 42%; RR 1.33; 95% CI: 1.02-1.75), the risk of caesarean section was increased (31% versus 22%; RR 1.48; 95% CI: 1.14-1.90), without a reduction of the risk of hyperstimulation. REVIEWER'S CONCLUSIONS: There is insufficient evidence to evaluate the effectiveness, in terms of likelihood of vaginal delivery in 24 hours, of mechanical methods compared with placebo/no treatment or with prostaglandins. The risk of hyperstimulation was reduced when compared with prostaglandins (intracervical, intravaginal or misoprostol). Compared to oxytocin in women with unfavourable cervix, mechanical methods reduce the risk of caesarean section. There is no evidence to support the use of extra-amniotic infusion.

Catheterization↗
PubMed2000

Macrolide antibiotics for cystic fibrosis.

BACKGROUND: Cystic Fibrosis is characterised by chest infection, the antibiotic treatment of which has significantly improved the outlook for people with this condition. The unusual nature of organisms that infect the chest of individuals with cystic fibrosis has restricted antibiotic choice. In particular the bacteria, Pseudomonas aeruginosa, is resistant to nearly all antibiotics that can be taken by mouth. There is laboratory evidence and evidence from other disease processes that macrolide antibiotics, whilst not directly active against Pseudomonas aeruginosa, may have indirect actions against this bacteria. OBJECTIVES: This review aimed to test the hypotheses that macrolide antibiotics; 1) Improve clinical status compared to placebo or another antibiotic 2) do not have unacceptable adverse effects If benefit was demonstrated, we aimed to assess the optimal type, dose and duration of macrolide therapy. SEARCH STRATEGY: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group specialist trials register which comprises references identified from comprehensive electronic database searches, handsearching relevant journals and handsearching abstract books of conference proceedings. In addition, Principal Investigators, known to work in the field and previous authors were contacted for unpublished or follow up data. Pharmaceutical companies, that manufacture macrolide antibiotics, were approached. SELECTION CRITERIA: Randomised controlled trials, published or unpublished, of macrolide compared to placebo, another class of antibiotic or another macrolide. Studies which compare regimes of the same macrolide at different doses will also be included. DATA COLLECTION AND ANALYSIS: No completed randomised controlled trials were identified. MAIN RESULTS: Three open studies excluded. Four ongoing randomised controlled trials were identified. No completed randomised controlled trials were identified. REVIEWER'S CONCLUSIONS: At present, there are no randomised controlled trials to evaluate the use of macrolide antibiotics for the treatment of chest infection in people with cystic fibrosis. Such trials, with clear outcome measures, are needed to properly evaluate this potentially useful treatment for cystic fibrosis.

Anti-Bacterial Agents↗
PubMed2004

Macrolide antibiotics for cystic fibrosis.

BACKGROUND: Chronic severe infection with Pseudomonas aeruginosa, affects many people with cystic fibrosis (CF). There is evidence from the laboratory and from other disease processes that macrolide antibiotics, whilst not directly active against Pseudomonas aeruginosa, may have indirect actions against this organism. OBJECTIVES: We aimed to test the hypotheses that, in people with CF, macrolide antibiotics:(1) improve clinical status compared to placebo or another antibiotic;(2) do not have unacceptable adverse effects. If benefit was demonstrated, we aimed to assess the optimal type, dose and duration of macrolide therapy. SEARCH STRATEGY: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group trials register comprising references identified from comprehensive electronic database searches, handsearching relevant journals and abstract books of conference proceedings. We contacted principal investigators known to work in the field, previous authors and pharmaceutical companies who manufacture macrolide antibiotics for unpublished or follow-up data (December 2003). Most recent search of the Group's register: January 2004 SELECTION CRITERIA: Published or unpublished randomised controlled trials of macrolide antibiotics compared to placebo, another class of antibiotic or another macrolide antibiotic. Studies comparing regimens of the same macrolide antibiotic at different doses will also be included. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed study quality. Three groups were contacted for missing data and we hope to include these in future reviews. MAIN RESULTS: Searches identified 14 studies, four were included in this review (296 participants). Two studies enrolled adults, one children (a significant number of whom were not colonised with Pseudomonas aeruginosa) and one both adults and children. All the clinical studies reported small but significant improvements in respiratory function with azithromycin versus placebo. Meta-analysis at the one-month and six-month time points demonstrates a significant benefit with respect to relative change in FEV1 (at six months, for n = 104, azithromycin and n = 114, placebo; WMD 5.82% (95% CI 2.45 to 9.20)). The largest study reported a significant increase in mild adverse events (nausea, diarrhoea and wheezing). REVIEWERS' CONCLUSIONS: There is clear evidence from these studies of a small but significant improvement in respiratory function following treatment with azithromycin. The largest study employed a three times a week dose and, in this study, treatment with azithromycin was associated with a significant increase in mild adverse events. Further studies are needed to clarify the precise role of azithromycin in the treatment of CF lung disease.

Anti-Bacterial Agents↗
PubMed2006

Pharmacotherapy for post traumatic stress disorder (PTSD).

BACKGROUND: Post traumatic stress disorder (PTSD) is a prevalent and disabling disorder. Evidence that PTSD is characterised by specific psychobiological dysfunctions has contributed to a growing interest in the use of medication in its treatment. OBJECTIVES: To assess the effects of medication for post traumatic stress disorder. SEARCH STRATEGY: We searched the Cochrane Depression, Anxiety and Neurosis Group specialised register (CCDANCTR-Studies) on 18 August 2005, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library issue 4, 2004), MEDLINE (January 1966 to December 2004), PsycINFO (1966 to 2004), and the National PTSD Center Pilots database. Reference lists of retrieved articles were searched for additional studies. SELECTION CRITERIA: All randomised controlled trials (RCTs) of pharmacotherapy for PTSD. DATA COLLECTION AND ANALYSIS: Two raters independently assessed RCTs for inclusion in the review, collated trial data, and assessed trial quality. Investigators were contacted to obtain missing data. Summary statistics were stratified by medication class, and by medication agent for the selective serotonin reuptake inhibitors (SSRIs). Dichotomous and continuous measures were calculated using a random effects model, heterogeneity was assessed, and subgroup/sensitivity analyses were undertaken. MAIN RESULTS: 35 short-term (14 weeks or less) RCTs were included in the analysis (4597 participants). Symptom severity for 17 trials was significantly reduced in the medication groups, relative to placebo (weighted mean difference -5.76, 95% confidence intervals (CI) -8.16 to -3.36, number of participants (N) = 2507). Similarly, summary statistics for responder status from 13 trials demonstrated overall superiority of a variety of medication agents to placebo (relative risk 1.49, 95% CI 1.28 to 1.73, number needed to treat = 4.85, 95% CI 3.85 to 6.25, N = 1272). Medication and placebo response occurred in 59.1% (N = 644) and 38.5% (628) of patients, respectively. Of the medication classes, evidence of treatment efficacy was most convincing for the SSRIs. Medication was superior to placebo in reducing the severity of PTSD symptom clusters, comorbid depression and disability. Medication was also less well tolerated than placebo. A narrative review of 3 maintenance trials suggested that long term medication may be required in treating PTSD. AUTHORS' CONCLUSIONS: Medication treatments can be effective in treating PTSD, acting to reduce its core symptoms, as well as associated depression and disability. The findings of this review support the status of SSRIs as first line agents in the pharmacotherapy of PTSD, as well as their value in long-term treatment. However, there remain important gaps in the evidence base, and a continued need for more effective agents in the management of PTSD.

Antidepressive Agents↗
PubMed2000

Amniotomy alone for induction of labour.

BACKGROUND: Amniotomy (deliberate rupture of the membranes) is a simple procedure which can be used alone for induction of labour if the membranes are accessible, thus avoiding the need for pharmacological intervention. However, the time interval from amniotomy to established labour may not be acceptable to clinicians and women, and in a number of cases labour may not ensue. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. OBJECTIVES: To determine the effects of amniotomy alone for third trimester labour induction in women with a live fetus. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group trials register, the Cochrane Controlled trials register and bibliographies of relevant papers. SELECTION CRITERIA: The criteria for inclusion included the following: (1) clinical trials comparing amniotomy alone for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods; (2) random or pseudo-random allocation to the treatment or control group; (3) ideally adequate allocation concealment (4) violations of allocated management not sufficient to materially affect conclusions; (5) clinically meaningful outcome measures reported; (6) data available for analysis according to the random allocation; (7) missing data insufficient to materially affect the conclusions. DATA COLLECTION AND ANALYSIS: This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. A strategy was developed to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction. The initial data extraction was done centrally, and incorporated into the series of primary reviews arranged by methods of induction of labour. The data from the primary reviews will be incorporated into a series of secondary reviews, arranged by category of woman to reflect clinical scenarios. To avoid duplication of data in the primary reviews, the labour induction methods have been listed in a specific order, from one to 25. Each primary review includes comparisons between one of the methods (from two to 25) with only those methods above it on the list. This review includes comparisons between amniotomy alone (number 5 on the list) with only those methods above it on the list (no treatment / placebo; intravaginal prostaglandins; intracervical prostaglandins; and oxytocin alone). MAIN RESULTS: Two trials comprising 50 and 260 women respectively were eligible for inclusion in this review. No conclusions could be drawn from comparisons of amniotomy alone versus no intervention, and amniotomy alone versus oxytocin alone (small trial, only one pre-specified outcome reported). No trials compared amniotomy alone with intracervical prostaglandins. One trial compared amniotomy alone with a single dose of vaginal prostaglandins for women with a favourable cervix, and found a significant increase in the need for oxytocin augmentation in the amniotomy alone group (44% versus 15%; RR 2.85, 95% CI 1.82-4.46). This should be viewed with caution as this was the result of a single centre trial. Furthermore, secondary intervention occurred 4 hours after amniotomy, and this time interval may not have been appropriate. REVIEWER'S CONCLUSIONS: Data is lacking about the value of amniotomy alone for induction of labour. While there are now other modern methods available for induction of labour (pharmacological agents), there remain clinical scenarios where amniotomy alone may be desirable and appropriate, and this method is worthy of further research. This research should include evaluation of the appropriate time interval from amniotomy to secondary intervention, women and caregivers' satisfaction and economic analysis.

Amnion↗
PubMed2000

Intravenous prostaglandin for induction of labour.

BACKGROUND: Intravenous prostaglandin E2 and F2 alpha can be used to induce labour. The use of intravenous prostaglandins in this context has been limited by perceived unacceptable maternal side effect profiles. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. OBJECTIVES: To determine the effects of intravenous prostaglandin for third trimester cervical ripening or induction of labour. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group trials register, The Cochrane Controlled Trials Register and bibliographies of relevant papers. SELECTION CRITERIA: The criteria for inclusion included the following: (1) clinical trials comparing intravenous prostaglandin used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods; (2) random allocation to the treatment or control group; (3) adequate allocation concealment; (4) violations of allocated management not sufficient to materially affect conclusions; (5) clinically meaningful outcome measures reported; (6) data available for analysis according to the random allocation; (7) missing data insufficient to materially affect the conclusions. DATA COLLECTION AND ANALYSIS: A strategy has been developed to deal with the large volume and complexity of trial data relating to labour induction. This involves a two-stage method of data extraction. The initial data extraction is done centrally, and incorporated into a series of primary reviews arranged by methods of induction of labour, following a standardised methodology. The data will then be extracted from the primary reviews into a series of secondary reviews, arranged by category of woman. To avoid duplication of data in the primary reviews, the labour induction methods have been listed in a specific order, from one to 25. Each primary review includes comparisons between one of the methods (from two to 25) with only those methods above it on the list. MAIN RESULTS: Thirteen trials were eligible for inclusion in this review. Two trials (comprising 400 women) compared intravenous prostaglandin E2 to intravenous oxytocin, a further seven trials (comprising 590 women) compared intravenous prostaglandin F2 alpha to intravenous oxytocin. Two trials (comprising 115 women) each randomised women to one of three treatment arms namely intravenous oxytocin or intravenous prostaglandin F2 alpha or prostaglandin E2. One trial reported a comparison of combined oxytocin and prostaglandin F2 alpha and oxytocin alone in 20 women and lastly one trial compared extra amniotic prostaglandin E2 versus intravenous prostaglandin E2 (40 women). The use of intravenous prostaglandin was associated with higher rates of uterine hyperstimulation with changes in the fetal heart rate (relative risk (RR) 6.76, 95% confidence interval (CI) 1.23-37.11) and without (RR 4.25, 95%CI 1.48-12.24) compared to oxytocin. Use of prostaglandins was also associated with significantly more maternal side effects (gastrointestinal, thrombophlebitis and pyrexia, RR 3.75, 95% CI 2.46-5.70) than oxytocin. Prostaglandin was no more likely to result in vaginal delivery than oxytocin (RR 0.85, 95% CI 0.61-1.18). No significant differences emerged from subgroup analysis or from the trials comparing combination oxytocin/prostaglandin F2 alpha and oxytocin or extra amniotic versus intravenous prostaglandin E2. REVIEWER'S CONCLUSIONS: Intravenous prostaglandin is no more efficient than intravenous oxytocin for the induction of labour but its use is associated with higher rates of maternal side effects and uterine hyperstimulation than oxytocin. No conclusions can be drawn form the comparisons of combination of prostaglandin F2 alpha and oxytocin compared to oxytocin alone or extra amniotic and intravenous prostaglandin E2.

Clinical Trials as Topic↗
PubMed2000

Mifepristone for induction of labour.

BACKGROUND: The steroid hormone, progesterone, inhibits contractions of the uterus. Antiprogestins (including mifepristone) have been developed to antagonise the action of progesterone, and these have a recognised role in medical termination of early or mid-pregnancy. Animal studies have suggested that mifepristone may also have a role in inducing labour in late pregnancy. OBJECTIVES: To determine the effects of mifepristone for third trimester cervical ripening or induction of labour. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register, the Cochrane Controlled Trials Register, and reference lists of relevant papers. SELECTION CRITERIA: Selection criteria included: (1) clinical trials comparing mifepristone used for third trimester cervical ripening or labour induction with placebo/no treatment or other labour induction methods; (2) random allocation to the treatment or control group; (3) adequate allocation concealment; (4) violations of allocated management not sufficient to materially affect conclusions; (5) clinically meaningful outcome measures reported; (6) data available for analysis according to the random allocation; (7) missing data insufficient to materially affect the conclusions. DATA COLLECTION AND ANALYSIS: This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. Data were extracted by the reviewer and, independently, by a colleague. MAIN RESULTS: Seven trials, that recruited 594 women, are included. All trials compared mifepristone with placebo, except for one that compared mifepristone with no treatment. Compared to placebo, mifepristone treated women were less likely to have an unfavourable cervix at 48 hours (relative risk [RR] 0.36, 95% confidence intervals [CI] 0.2-0.63) or 96 hours (RR 0.39, 95% CI 0.23-0.66). Mifepristone treated women were more likely to have delivered within 48 and 96 hours of treatment than were placebo treated/no treatment women - 48 hours: RR 2.82, 95% CI 1.82-4.36; 96 hours: RR 3.40, 95% CI 1.96-5.92. Mifepristone treated women were less likely to undergo caesarean section (RR 0.71, 95% CI 0.53-0.95). There is little information about fetal outcome, although there was no evidence that neonatal hypoglycaemia might be more common after exposure to mifepristone. Similarly, there is little information about maternal side-effects although some nausea and vomiting was reported in one trial. REVIEWER'S CONCLUSIONS: There is insufficient information available from clinical trials to support the use of mifepristone to induce labour. However, available data do show that mifepristone is better than placebo at ripening the cervix, and inducing labour. There is evidence of a possible reduction in the incidence of caesarean section following mifepristone treatment (compared to placebo) that would justify further trials. We found no trials that compared mifepristone with alternative methods of inducing labour e.g. prostaglandins.

Clinical Trials as Topic↗