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At least 325 records · Page 18Linked to original sources
PubMed2005

Influence of different posts and cores on marginal adaptation, fracture resistance, and fracture mode of composite resin crowns on human mandibular premolars. An in vitro study.

OBJECTIVE: To evaluate marginal adaptation, fracture modes, and loads to failure of composite crowns with different substructures on root-canal-treated premolars. METHODS: Forty-eight mandibular teeth with single root canals were selected and assigned to six equal groups: group I, untreated; group II, root-canal-treated (RCT), access cavity restored with composite resin; group III, RCT, ferrule (2 mm), no post, standardized composite resin crown (SRCC); group IV, RCT, ferrule, glass fiber post, SRCC; group V, RCT, ferrule, zirconium post, SRCC; group VI, RCT, ferrule, cast gold post, SRCC. All teeth were subjected to thermocycling and mechanical loading (TCML) in a computer-controlled masticator (1,200,000 loads, 49N, 1.7Hz, 3000 temperature cycles of 5-50-5 degrees C). Marginal adaptation was evaluated before and after TCML with scanning electron microscopy at x200 at the tooth-to-luting-composite (IF1) and the luting-composite-to-crown (IF2) interfaces. After TCML, all specimens were loaded to failure in a universal testing machine at 0.5mm/min. RESULTS: A significant decrease in marginal adaptation was found in groups III and IV after TCML at IF1. A significant decrease was observed at IF2 in group V. Mean loads to failure did not differ significantly between the groups with SRCCs. Those of groups II, III, and IV did not differ from that of unrestored teeth. Half the specimens exhibited partial root fractures, independent of the substructures used. No deep or vertical root fractures were observed in any group. CONCLUSION: All studied posts had a positive effect on marginal adaptation at IF1, but not on failure modes or loads to failure of composite resin crowns.

Acrylic Resins↗
PubMed2006

Pulpal inflammation and incidence of coronary heart disease.

Pulpal inflammation is primarily caused by coronal caries, and leads to root canal therapy (RCT). Chronic inflammation has been associated with various cardiovascular diseases. This study evaluates the association between pulpal inflammation (using RCT as a surrogate) and incident coronary heart disease (CHD). We report results among males from the Health Professionals Follow-Up Study (HPFS), excluding participants with prior cardiovascular disease or diabetes. We obtained RCT data from the HPFS cohort (n = 34,683). Compared to men without RCT, those with >/=1 RCT had a multivariate RR of 1.21 (95% CI 1.05-1.40) for CHD. The association was limited to dentists (RR = 1.38; 95% CI 1.14-1.67). There was no association among nondentists (RR = 1.03). Dental caries was not associated with CHD. The results suggest a possible modest association between pulpal inflammation and CHD.

Age Distribution↗
PubMed2026

EDucation and eXercise for gluteal tendinopathy in an Irish context (EDX-Ireland): findings from the LEAP-Ireland feasibility randomised controlled trial.

OBJECTIVE: To assess feasibility of a randomised controlled trial (RCT) investigating effectiveness of 6 sessions of an EDucation and eXercise intervention delivered over 8 weeks (EDX-Ireland) for gluteal tendinopathy, against usual care. EDX-Ireland was modified from a 14-session EDucation and eXercise intervention (EDX), delivered over 8 weeks, previously evaluated in an Australian RCT. DESIGN: Feasibility parallel RCT. METHODS: Participants were randomly assigned to physiotherapist-led EDX-Ireland or usual care. EDX-Ireland comprised 6 sessions of education, hip abductor strengthening and functional loading over 8 weeks, supported by a home exercise programme. Primary outcomes included success of different recruitment strategies and recruitment/retention rates. Secondary outcomes measured global rating of change and other clinical outcomes. Descriptive statistics (percentage, mean, standard deviations and 95% confidence intervals (CI)) are presented. RESULTS: Of 323 individuals who expressed interest in study participation, 119 completed physical examination screening, and 65 met criteria and consented to participate (recruitment rate 55%). Sixty-five people (89% women; mean age 53.1 ± 9.3 years), were randomised to EDX-Ireland (n = 32) or usual care (n = 33). Eighty-three percent (n = 54) were recruited via social media/community, 3% (n = 2) from general practitioners and 14% (n = 9) from orthopaedic/rheumatology. Retention was 92% (95% CI 82-97%, n = 60) at 8-weeks, and 89% (95% CI 79-96%, n = 58) at 3-months. Feasibility thresholds were met. Effect size estimates indicate that 134 participants would be required for a future RCT. CONCLUSION: Pre-defined recruitment and retention thresholds were met, indicating that a RCT evaluating 6 sessions of physiotherapist-delivered education and exercise against usual care for gluteal tendinopathy is feasible. TRIAL REGISTRATION: Clinicaltrials.gov (NCT05516563).

Humans↗
PubMed1996

Utility of the National Cooperative Growth Study database for safety reporting.

The National Cooperative Growth Study (NCGS) maintains the largest database in the world, collecting information on patients with growth disorders treated with growth hormone (GH). More than 24,000 children have been monitored during its first decade (1985 through 1995). The database provides unique opportunities to learn about effectiveness of GH therapy in a real-world context. Its size also makes it possible to investigate rare adverse reactions, which is not reasonable in a randomized controlled trial (RCT). The frequency of adverse experiences reported in an observational study like the NCGS is lower than in an RCT, because the investigators in an observational study typically do not report events that they believe are clearly unrelated to the study drug. Nevertheless the NCGS has greatly facilitated collecting adverse-event data; approximately 75% of all adverse-event reports for GH received by the manufacturer are through NCGS data-collection forms. The NCGS has thus amassed a repository of GH safety data that is unparalleled. Furthermore, in contrast to an RCT, the NCGS database reflects real-world experience with long-term GH therapy in North America. Although the advantages of an observational study such as the NCGS must be recognized, such a study does differ from an RCT in important ways. For example, because the NCGS protocol allows customized patient treatment and individualization of GH therapy, it may be difficult to use the database to address questions (e. g., estimation of dose-response relationships, true incidence of adverse events) that require RCT designs.

Adverse Drug Reaction Reporting Systems↗
PubMed1993

Healing of induced periapical lesions in ferret canines.

A previous study showed that the ferret canine is an appropriate model for inducing periapical lesions. Ferret canines were used in this study to study changes in periapical lesions after root canal treatment (RCT). After periapical pathosis was induced in the maxillary and mandibular canines of six ferrets, RCT was performed on three of the four canines in each animal. Each ferret received periodic intraperitoneal injections of Procion red dye. Two animals were killed at each of 4, 8, and 12 wk after RCT. Apices and surrounding lesions were evaluated radiographically, histologically, and by fluorescent microscopy. Periapical radiolucencies increased in size during induction but showed no changes after RCT. Lesions in untreated teeth showed features of granulomatous inflammation, mainly the presence of macrophages and lymphocytes. After RCT, there was histological evidence of healing in the form of cementum deposition, increased vascularity, and increased fibroblastic and osteoblastic activity. Fluorescent staining showed cementum deposition of variable thickness in the treated specimens.

Animals↗
PubMed1999

In vitro fracture strength of endodontically treated premolars.

The recent introduction of new bonding agents has led some authors to suggest that certain endodontically treated posterior teeth could be restored with a bonded restoration instead of a full-coverage crown or onlay. To test the fracture resistance of endodontically treated premolars restored with and without bonding agents, we randomly divided 56 intact and caries-free maxillary premolars into seven groups as follows: unaltered teeth; access only; MOD prep and RCT; MOD prep, RCT, and amalgam restoration; MOD prep, RCT, and amalgam with 4-META bonding agent; MOD prep, RCT, and composite resin restoration; and MOD prep, RCT, and composite resin with 4-META bonding agent. The teeth were subjected to compressive fracture tests in a Zwick 1435 Universal Testing Machine. Unaltered teeth and those with access only demonstrated similar fracture strengths. Under the conditions of this study, there was no significant difference in fracture strength between the experimental groups.

Acrylic Resins↗
PubMed1990

Measurement of circulation time in the retinal vasculature using selective angiography.

Retinal circulation times (RCT) and mean circulation time (MCT) in the retinal vasculature have been used to determine the effect of ocular disease on retinal circulation. Both RCT and MCT are usually determined by measuring dye dilution curves during a traditional fluorescein angiogram. The authors present a variation of the dye dilution technique. The primary difference is that a fluorescent dye (carboxyfluorescein or calcein) was encapsulated in liposomes at a very high concentration. The dye was then released at a specific site in a retinal artery by the application of a laser pulse delivered through the pupil of the eye. The heat pulse produced by the laser lysed the liposomes in the targeted vessel, causing a stream of dye to be released. The time it took the dye front to pass through the artery and return through the vein (RCT) was then measured. To clarify the situation, two times were actually measured, the shortest path the dye traveled from the exposure site to a corresponding site on the vein (short RCT) and the longest path through the periphery to venous filling (long RCT). The measurements were made in both cynomolgus monkeys and squirrel monkeys. The local dye release achieved with this method was found to produce a more distinct dye front than traditional angiography while also eliminating the problem of recirculation. Choroidal background fluorescence, a factor that often obscures the dye front in traditional angiography, was minimal. Furthermore, it was possible to make individual measurements on each of the four arteries and to repeat the measurements several times.

Animals↗
PubMed2003

Neck dissection following radiochemotherapy of advanced head and neck cancer--for selected cases only?

PURPOSE: To address the value of neck dissection (ND) in patients with advanced head and neck cancer following primary radiochemotherapy and to specifically analyse its impact on locoregional tumour control, survival and toxicity. PATIENTS AND METHODS: Between 1987 and 1997 (9,335), a total of 142 patients (pts) were treated by primary radiochemotherapy (RCT) according to prospective protocols. There were 64 pts with involvement of the hypopharynx, 57 pts with oropharyngeal and 21 with oral cavity carcinoma. UICC (1997) stages included: 16 pts in stage III, 113 pts in stage IV A, 13 pts in stage IV B. All pts received platin-based RCT up to a median total dose of 70 Gy (range, 60-72 Gy). Six weeks after RCT, pts with complete response of the primary tumour (N=97) were offered a uni- or bilateral ND depending on the initially diagnosed nodal disease as part of a strict institutional policy. Fifty-six pts consented to ND and 41 refused. These two groups were analysed in terms of characteristics, local and regional tumour control, survival and long-term side effects. Median follow-up was 37 months (range, 22-124 months). RESULTS: Among the 56 pts receiving ND, a total of 13 (23%) was found to have residual tumour in the neck specimen. The rates of positive histology according to clinical N category after RCT were: yN0 (2/22[9%]), yN1 (2/10[20%]), yN2a-b (2/10[20%), yN2c-3 (7/14[54%]). Five-year overall survival and disease-specific survival rates for pts with ND were 44 and 55%, for pts without ND 42 and 47%, respectively (P=0.9). No difference was seen for long-term local and regional control between the two patient groups. Comparing the group of patients with and without ND, a trend towards higher subjective morbidity of grade 3 and 4 (LENT-SOMA), i.e. pain recording (24% vs. 17%), dysphagia (48% vs. 35%) and hoarseness (20% vs. 9%) was evident in patients with ND. CONCLUSION: No clear evidence for routine clinical use of ND after RCT in advanced head and neck tumours can be derived from these data. ND may be contemplated in selected cases with multiple residual nodes only.

Adult↗
PubMed2001

Concomitant radiochemotherapy of advanced non-small-cell lung cancer.

Concurrent radiochemotherapy (RCT) is a promising new therapy option in advanced non-small cell lung cancer (NSCLC). In randomized trials concomitant RCT has been shown to be superior compared to radiotherapy alone and to sequential radiochemotherapy. In most treatment schedules platinum salts alone or in combination with etoposide, mitomycin C or vinca-alkaloids have been used. Up to now altered fractionation schemas-particularly hyperfractionated radiotherapy-have not been demonstrated to be superior to conventional fractionation (2 Gy daily up to 56-60 Gy), when employed concurrently to chemotherapy. Nevertheless open questions remain: (1) What is the best chemotherapy administered simultaneously to radiotherapy? (2) Might newer drugs (e.g. taxanes, inhibitors of topoisomerase I and II, gemcitabine) be more effective and reveal fewer side effects compared to platinum salts? (3) Is there a role for adjuvant chemotherapy following RCT? (4) What is the most effective radiotherapy schedule in concepts with RCT? (5) What radiation dose is necessary to optimize local control in RCT?

Carcinoma, Non-Small-Cell Lung↗
PubMed2001

Influence of preoperative combined radiochemotherapy on surgical outcome and colonic anastomotic healing: experimental study in the rat.

PURPOSE: To study the influence of combined preoperative hyperfractionated irradiation with intraperitoneal 5-fluorouracil (5-FU) on surgical outcome and colonic anastomotic healing in a rat model. METHODS: Male Wistar rats were given 41.6 Gy of preoperative radiotherapy (RT) or sham irradiation, with intraperitoneal 5-FU at low dose (10 mg/kg) or high dose (20 mg/kg). Animals were arranged in 6 groups: RT + low-dose 5-FU (RCT-L), RT + high-dose 5-FU (RCT-H), sham RT + low-dose 5-FU (CT-L), sham RT + high-dose 5-FU (CT-H), RT alone (R), and a control group (sham RT + intraperitoneal saline). Side-to-side colonic anastomoses were constructed from one irradiated and one nonirradiated limb 4 days after radiochemotherapy. Animals were sacrificed 10 days after surgery. RESULTS: Compared to controls, more complications occurred in group RCT-H (50% versus 0%, p = 0.01). Adhesion formation was more intense in groups RCT-H and CT-H (p < 0.001 and p = 0.001, respectively). After therapy, white blood cell counts dropped significantly in all irradiated animals (p < 0.01), and platelet counts decreased significantly in group RCT-H (p = 0.01). No significant differences were noticed in anastomotic bursting pressure when the treated groups were compared to each other or to the control group. CONCLUSIONS: Neoadjuvant radiochemotherapy has no adverse effect on the strength of colonic anastomosis in this rat model. However, the combined RT with high-dose 5-FU does increase operative morbidity and adhesion formation.

Anastomosis, Surgical↗
PubMed2000

Apoptosis, p53, bcl-2, and Ki-67 in invasive bladder carcinoma: possible predictors for response to radiochemotherapy and successful bladder preservation.

PURPOSE: Several groups have reported the value of bladder preservation by a combined treatment protocol, including transurethral resection (TUR-B) and radiochemotherapy (RCT). As more experience is acquired with organ-sparing treatment, patient selection should be optimized. The purpose of this study was to investigate the role of several biologic markers that may predict response to RCT in muscle-invasive bladder carcinoma. METHODS AND MATERIALS: The apoptotic index (AI), Ki-67, p53, and bcl-2 were evaluated by immunohistochemistry on pretreatment biopsies from 70 patients treated for invasive bladder cancer by TUR-B and RCT. Expression of each marker was correlated with initial response, local control, and cancer-specific survival with preserved bladder. An exploratory multivariate analysis was also performed that included clinical and immunohistochemical variables. RESULTS: A high AI (> median = 1.6%) and a high Ki-67 index (> median = 8.8%), but not the p53- and bcl-2 expression, were significantly related to initial complete response (CR) and local control with preserved bladder after 5 years. When the AI and Ki-67 expression were considered simultaneously, the association with initial CR (p < 0. 001), local control (p = 0.0002), and cancer-specific survival with preserved bladder (p = 0.008) was highly significant. In an exploratory multivariate analysis (final model), only AI, Ki-67, and the combined AI/Ki-67 variable retained significance for local control with preserved bladder at 5 years. CONCLUSION: Patients with a high spontaneous AI and a high pretreatment Ki-67 index should be considered preferentially for treatment with RCT, whereas tumors with low proliferation and low levels of apoptosis are less likely to respond to RCT.

Aged↗
PubMed1997

A prospective comparison of four study designs used in assessing safety and effectiveness of drug therapy in hypertension management.

The objective of the study was to compare prospectively the impact of study design on drug therapy safety and effectiveness data obtained in hypertension management. The main study was a randomized controlled clinical trial of four different prospective study designs used in postmarketing assessment involving 1008 primary care practices in nine Canadian provinces. Two thousand nine hundred sixty-four patients with mild to moderate hypertension received an angiotensin converting enzyme (ACE) inhibitor daily for 14 weeks in one of four postmarketing studies--a randomized double-blind clinical trial (RCT) (10 to 40 mg fosinopril daily v 5 to 20 mg enalapril daily), two structured open label trials of 10 to 40 mg fosinopril daily (one with free drugs), or an unstructured open label trial of 10 to 40 mg fosinopril daily. Patient demographic and baseline characteristics, systolic and diastolic blood pressures, adverse events reported, and data quality were recorded as the outcome measures. The results showed that the RCT patients were titrated to higher doses of ACE inhibitor than patients in the open studies, P < .008; patients in the open studies were more likely to receive adjuvant diuretic therapy, P < .008. The decrease in blood pressure was similar for patients in all four studies, mean decrease in systolic BP was between 18 and 20 mm Hg, mean decrease in diastolic BP was between 11 and 13 mm Hg. Fewer patients in the unstructured open trial reported adverse events than patients in the RCT; a 55% relative reduction in reported adverse events (P < .008) was associated with the unstructured trial. There were also fewer drug-related adverse events per patient reported in the unstructured study (17 per 100 patients) than in the other studies (27 to 41 per 100 patients), P < .008. Physician preference for rounding off blood pressure measurements to 0 or 5 occurred most often in the unstructured open trial (P < .008). In conclusion, despite differences in dose titration and in the use of adjuvant therapy, antihypertensive drug therapy effectiveness observed in an RCT may be similar to uncontrolled postmarketing studies. Open trials with scheduled follow-up visits are as effective in detecting severe adverse events as RCT, but postmarketing studies with unstructured schedules of follow-up are insufficient in identifying drug-related adverse events and have poorer quality data.

Antihypertensive Agents↗
PubMed2001

Surgery, radio- and chemotherapy for multimodal treatment of rectal cancer.

The possibilities and results of multimodal treatment in rectal cancer were reviewed with respect to the results of surgical treatment only. Based on the results of 4 studies, reducing local relapse rates and increasing long term survival rates significantly, postoperative radiochemotherapy (RCT) + chemotherapy (CT) should remain the recommended standard for R0 resected UICC II and III rectal cancers. The addition of RT to adjuvant CT reduces local relapses without significant impact on survival (NSABP R-02). Vice versa, the addition of CT to RT or an improved CT in the RCT-concept prolongs survival. Preoperative neoadjuvant radiotherapy (RT) reduced local relapse rates in 9 studies, and extended survival in one study that evaluated all eligible patients. Preoperative RT reduced local relapse rates in addition to total mesorectal excision (TME) but did not extend survival. The preoperative RCT + CT downstages resectable and nonresectable tumors and induces a higher sphincter preservation rate. Phase III data justifying its routine use in all UICC II + III stages are not yet available. This treatment may be routinely applied in nonresectable primary tumors or local relapses. Preoperative RCT (or RT) may evolve as standard, if the patient selection is improved and postoperative morbidity and long term toxicity reduced. Intraoperative RT could be added to this concept or be used together with preoperative/postoperative RT at the same indications. Postoperative adjuvant RT reduced local relapses significantly in a single trial, and no impact on survival time is reported. Since postoperative RT is inferior to preoperative RT, this treatment cannot be recommended, if RT is chosen as a single treatment modality in adjunction to surgery. The results of local tumor excisions may be improved with pre- or postoperative RCT + CT. In the future, multimodal treatment of rectal cancer might be more effective, if individualized according to prognostic factors.

Chemotherapy, Adjuvant↗
PubMed2005

Integrating evidence-based teaching into to clinical practice should improve outcomes.

DATA SOURCES: Sources used were Medline, Embase, the Education Resources Information Centre , Cochrane Controlled Trials Register, Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects, Health Technology Assessment database, Best Evidence, Best Evidence Medical Education and Science Citation Index, along with reference lists of known systematic reviews. STUDY SELECTION: Studies were chosen for inclusion if they evaluated the effects of postgraduate evidence-based medicine (EBM) or critical appraisal teaching in comparison with a control group or baseline before teaching, using a measure of participants' learning achievements or patients' health gains as outcomes. DATA EXTRACTION AND SYNTHESIS: Articles were graded as either level 1 (randomised controlled trials (RCT)) or level 2 (non-randomised studies that either had a comparison with a control group), or a before and after comparison without a control group. Learning achievement was assessed separately for knowledge, critical appraisal skills, attitudes and behaviour. Because of obvious heterogeneity in the features of individual studies, their quality and assessment tools used, a meta-analysis could not be carried out. Conclusions were weighted by methodological quality. RESULTS: Twenty-three relevant studies were identified, comprising four RCT, seven non-RCT, and 12 before and after comparison studies. Eighteen studies (including two RCT) evaluated a standalone teaching method and five studies (including two RCT) evaluated a clinically integrated teaching method. CONCLUSIONS: Standalone teaching improved knowledge but not skills, attitudes or behaviour. Clinically integrated teaching improved knowledge, skills, attitudes and behaviour. Teaching of EBM should be moved from classrooms to clinical practice to achieve improvements in substantial outcomes.

Comment↗
PubMed2003

The randomised controlled trial design: unrecognized opportunities for health sciences librarianship.

OBJECTIVE: to describe the essential components of the Randomised Controlled Trial (RCT) and its major variations; to describe less conventional applications of the RCT design found in the health sciences literature with potential relevance to health sciences librarianship; to discuss the limited number of RCTs within health sciences librarianship. METHODS: narrative review supported to a limited extent with PubMed and Library Literature database searches consistent with specific search parameters. In addition, more systematic methods, including handsearching of specific journals, to identify health sciences librarianship RCTs. RESULTS: While many RCTs within the health sciences follow more conventional patterns, some RCTs assume certain unique features. Selected examples illustrate the adaptations of this experimental design to answering questions of possible relevance to health sciences librarians. The author offers several strategies for controlling bias in library and informatics applications of the RCT and acknowledges the potential of the electronic era in providing many opportunities to utilize the blinding aspects of RCTs. RCTs within health sciences librarianship inhabit a limited number of subject domains such as education. This limited scope offers both advantages and disadvantages for making Evidence-Based Librarianship (EBL) a reality. CONCLUSIONS: The RCT design offers the potential to answer far more EBL questions than have been addressed by the design to date. Librarians need only extend their horizons through use of the versatile RCT design into new subject domains to facilitate making EBL a reality.

Evidence-Based Medicine↗
PubMed2000

Methodological issues in papers on IFN therapy: time for reappraisal.

We conducted an analytical review of 194 full papers on interferon (IFN) therapy for chronic hepatitis C to evaluate current methodology (i.e. study design, criteria for evaluating the efficacy of therapy and predictors of response). Of the papers evaluated, 64 were randomized controlled trials (RCT), 40 were non-randomized controlled trials (NRCT) and 90 were observational studies (OS). The methodological analysis was focused mainly on clinical trials. The number of patients enrolled in RCT was higher compared with the number enrolled in NRCT. Uniform enrolment criteria were used in less than 50% of the trials. Only 20% of RCT and 2.5% of NRCT used criteria for defining sample size. The response rate was calculated on an intention-to-treat basis in 36 of the RCT and in 14 of the NRCT. The outcome of treatment and the criteria employed to define the response to treatment were found to be far from standardized. In 51.5% of the RCT and 42.5% of the NRCT, normalization of alanine aminotransferase (ALT) level at the end of follow-up was the only marker of response studied. Only 57.6% of the trials considered histological evidence as an important outcome. Among the clinical trials, 71.1% evaluated predictors of good response to IFN therapy. In 51% of the OS, ALT normalization by the end of follow-up was the only criterion for defining response. In conclusion, to ensure a high level of reliability in comparing or combining the results of different studies, some basic general requirements must be followed when planning trials on antiviral therapy.

Antiviral Agents↗
PubMed2001

Survival on long-term oxygen therapy in chronic airflow limitation: from evidence to outcomes in the routine clinical setting.

BACKGROUND: Two previous randomized controlled trials (RCT) demonstrated that the administration of long-term oxygen therapy (LTOT) improved survival in selected patients with hypoxic chronic obstructive pulmonary disease (COPD) or chronic airflow limitation (CAL). AIMS: The aim of the present study was to investigate whether the survival of CAL patients prescribed LTOT at Flinders Medical Centre (FMC) was gender and age related, and equivalent to that of the previous RCT. METHODS: A list of patients prescribed domiciliary oxygen therapy for CAL at FMC was generated from Respiratory Unit records and hospital financial records for the supply of this therapy. Survival was compared with that reported for the original RCT, and for Swedish and Belgian COPD patients. Factors influencing survival were studied. RESULTS: Five hundred and five (249 males, 256 females) patients were prescribed LTOT for CAL at FMC during the study period and included in the survival analysis. The patients were elderly with multiple comorbidities. Survival was less than for the control arms of the previous RCT (apart from the Medical Research Council Working Party (MRC) female group) but comparable with recent overseas data. Overall crude survival was 75.1%, 51.3%, 18.9% and 1.1% at 1, 2, 5 and 10 years respectively. Females experienced longer survival than males. Multivariate analysis indicated that age, forced expiratory volume in 1 s, body mass index (BMI) and the number of comorbidities were prognostic indicators for females; BMI was a prognostic indicator for males. A survival advantage existed for females using at least 19 h concentrator oxygen per day. CONCLUSIONS: In routine practice, survival of unselected CAL patients with multiple comorbidities is less than that reported in the original RCT.

Age Factors↗
PubMed1977

The epidemiology of the gastrointestinal randomized clinical trial.

Has the randomized clinical trial (RCT), generally accepted as the method of choice for evaluation of most treatments, obtained a footing in gastroenterology? Among 35,228 citations on gastroenterologic therapy indexed in MEDLARS 1964-1974 306 (0.9 per cent) were RCT's. During the decade their frequency rose significantly (P less than 0.05) from 0.3 per cent in 1964 to 1.7 per cent in 1973. The "typical" RCT was a double-blind two-group comparison of a new and an established drug on the symptoms of peptic ulcer; 50 patients were followed for six weeks, and the number of dropouts was unknown. The new drug was found to be more effective. It is postulated that the RCT's in gastroenterology are quantitatively and qualitatively insufficient and that co-ordinated planning of RCT's and uninhibited publication of statistically proved negative results may help to ensure that the patient with gastrointestinal disease receives the best available treatment.

Europe↗