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A Gray

Publications and source records attributed to A Gray.

At least 37 records · Page 2Linked to original sources
PubMed2004

Identifying the psychosocial correlates of condom use by female sex workers in Hong Kong.

This study examined factors affecting condom use by Hong Kong female sex workers when they have sex with their clients and steady partners. Our respondents consisted of 109 active female sex workers, mainly streetwalkers or sex workers who worked in villas. During a 30-minute interview, respondents were interviewed individually and were asked questions regarding their condom use practice. These questions were designed to measure various factors affecting their condom use practice, including attitudes toward condom use, normative pressure, perceived behavioural control, perceived AIDS risks, past condom use behaviour, and future condom use intentions with respect to the two types of partners. Multiple regression analyses reveal that perceived behavioural control is the most important factor associated with these respondents' future condom use across the two types of partners. Perceived AIDS risk is the additional predictor for condom use with clients, while normative pressure is the additional predictor for condom use with steady partners. Past condom use behaviour also provided significant additional prediction for both types of partners, implying the habitual nature of condom use among our respondents. These results have significant implications for designing intervention programmes targeting at increasing condom use by female sex workers in Hong Kong.

Acquired Immunodeficiency Syndrome↗
PubMed2004

Secondary transport of the critically ill and injured adult.

There is significant interest in the secondary transport of the critically ill and injured. High profile cases entailing the long distance transfer of patients have highlighted the lack of availability of critical care beds and appropriate systems for transferring this patient group. These and other issues have culminated in the release of Comprehensive Critical Care by the Department of Health in 2000. It has been shown that a large number of critical care transfers originate in the emergency department. The transportation of patients has not traditionally been part of the core curriculum of emergency medicine specialists in the UK. It is imperative that clinicians have an understanding of the issues surrounding transportation of the critically ill and injured. This should include appreciation of the local and regional organisational frameworks implemented for this patient group. This review describes the core issues relevant to emergency medicine relating to the transportation of the critically ill and injured.

Adult↗
PubMed2003

The impact of diabetes-related complications on healthcare costs: results from the United Kingdom Prospective Diabetes Study (UKPDS Study No. 65).

AIMS: To develop a model for estimating the immediate and long-term healthcare costs associated with seven diabetes-related complications in patients with Type 2 diabetes participating in the UK Prospective Diabetes Study (UKPDS). METHODS: The costs associated with some major complications were estimated using data on 5102 UKPDS patients (mean age 52.4 years at diagnosis). In-patient and out-patient costs were estimated using multiple regression analysis based on costs calculated from the length of admission multiplied by the average specialty cost and a survey of 3488 UKPDS patients' healthcare usage conducted in 1996-1997. RESULTS: Using the model, the estimate of the cost of first complications were as follows: amputation pound 8459 (95% confidence interval pound 5295, pound 13 200); non-fatal myocardial infarction pound 4070 ( pound 3580, pound 4722); fatal myocardial infarction pound 1152 ( pound 941, pound 1396); fatal stroke pound 3383 ( pound 1935, pound 5431); non-fatal stroke pound 2367 ( pound 1599, pound 3274); ischaemic heart disease pound 1959 ( pound 1467, pound 2541); heart failure pound 2221 ( pound 1690, pound 2896); cataract extraction pound 1553 ( pound 1320, pound 1855); and blindness in one eye pound 872 ( pound 526, pound 1299). The annual average in-patient cost of events in subsequent years ranged from pound 631 ( pound 403, pound 896) for heart failure to pound 105 ( pound 80, pound 142) for cataract extraction. Non-in-patient costs for macrovascular complications were pound 315 ( pound 247, pound 394) and for microvascular complications were pound 273 ( pound 215, pound 343) in the year of the event. In each subsequent year the costs were, respectively, pound 258 ( pound 228, pound 297) and pound 204 ( pound 181, pound 255). CONCLUSIONS: These results provide estimates of the immediate and long-term healthcare costs associated with seven diabetes-related complications.

Ambulatory Care↗
PubMed2003

Respiration of 13C-labeled substrates added to soil in the field and subsequent 16S rRNA gene analysis of 13C-labeled soil DNA.

Our goal was to develop a field soil biodegradation assay using (13)C-labeled compounds and identify the active microorganisms by analyzing 16S rRNA genes in soil-derived (13)C-labeled DNA. Our biodegradation approach sought to minimize microbiological artifacts caused by physical and/or nutritional disturbance of soil associated with sampling and laboratory incubation. The new field-based assay involved the release of (13)C-labeled compounds (glucose, phenol, caffeine, and naphthalene) to soil plots, installation of open-bottom glass chambers that covered the soil, and analysis of samples of headspace gases for (13)CO(2) respiration by gas chromatography/mass spectrometry (GC/MS). We verified that the GC/MS procedure was capable of assessing respiration of the four substrates added (50 ppm) to 5 g of soil in sealed laboratory incubations. Next, we determined background levels of (13)CO(2) emitted from naturally occurring soil organic matter to chambers inserted into our field soil test plots. We found that the conservative tracer, SF(6), that was injected into the headspace rapidly diffused out of the soil chamber and thus would be of little value for computing the efficiency of retaining respired (13)CO(2). Field respiration assays using all four compounds were completed. Background respiration from soil organic matter interfered with the documentation of in situ respiration of the slowly metabolized (caffeine) and sparingly soluble (naphthalene) compounds. Nonetheless, transient peaks of (13)CO(2) released in excess of background were found in glucose- and phenol-treated soil within 8 h. Cesium-chloride separation of (13)C-labeled soil DNA was followed by PCR amplification and sequencing of 16S rRNA genes from microbial populations involved with (13)C-substrate metabolism. A total of 29 full sequences revealed that active populations included relatives of Arthrobacter, Pseudomonas, Acinetobacter, Massilia, Flavobacterium, and Pedobacter spp. for glucose; Pseudomonas, Pantoea, Acinetobacter, Enterobacter, Stenotrophomonas, and Alcaligenes spp. for phenol; Pseudomonas, Acinetobacter, and Variovorax spp. for naphthalene; and Acinetobacter, Enterobacter, Stenotrophomonas, and Pantoea spp. for caffeine.

Bacteria↗
PubMed2003

Descriptive epidemiology of adult critical care transfers from the emergency department.

AIMS: To describe the nature, frequency, and characteristics of adult critical care transfers originating from the emergency department (ED). METHODS: A one year prospective regional descriptive study using multiple data sources of all critically ill adults transferred from an ED or a minor injuries unit (MIU) within the former Yorkshire Regional Health Authority Area or into a regional critical care facility if originating from an ED or MIU elsewhere. RESULTS: 29 EDs transferred 349 adults into the regional critical care facilities. The median number of transfers per department within the region was 18 (range 1 to 42). Seventeen were transferred from outside the region. A total of 263 (75%) patients were transferred for specialist care and 76 (22%) for non-clinical reasons. Altogether 294 (84%) were admitted to intensive care or a high dependency unit at the receiving hospital. The in-hospital documented mortality rate was 26%. A total of 170 patients (49%) had traumatic pathology of which 101 were principally transferred for management of a head injury. Median time in the ED was 3 hours 5 minutes (range 11 minutes to 17 hours 47 minutes). In 146 (42%) patients the decision to transfer was primarily made by the emergency medicine clinician. A total of 251 (72%) patients were intubated. The documented critical incident rate was 15%. CONCLUSION: Trauma is the most common reason for transfer of the critically ill adult from the ED. A significant number of patients are transferred, however, with medical and surgical conditions and for non-clinical reasons. There continues to be problems with the quality of care that these patients receive. Emergency medicine clinicians must be actively involved in the development of regional critical care systems as a significant proportion of all critically ill adults transferred originate from the ED.

Adult↗
PubMed2002

Fluctuations in attention: PD dementia vs DLB with parkinsonism.

BACKGROUND: Marked impairments in and fluctuation of attention are characteristic of dementia with Lewy bodies (DLB). The comparative impairment of these cognitive domains in PD and PD dementia (PD dementia) has not been studied, and is important to the conceptual understanding of parkinsonian dementias. METHOD: Detailed evaluations of attention and fluctuating attention (Cognitive Drug Research computerized battery) were undertaken in 278 subjects (50 DLB, 48 PD dementia, 50 PD, 80 AD, 50 elderly controls) from the Newcastle dementia register and the Stavanger PD register (controls, PD, and PD dementia patients were recruited from both centers). DLB, AD, PD, and PD dementia were diagnosed using operationalized criteria. RESULTS: Impairments in reaction time, vigilance, and fluctuating attention were comparable in patients with DLB and PD dementia, but were less substantially impaired in patients with DLB without parkinsonism. Patients with PD had significantly greater impairment of cognitive reaction time than elderly controls, and comparable impairments of cognitive reaction time to patients with AD. Patients with PD, however, did not exhibit fluctuation of attention. CONCLUSION: The profile of attentional impairments and fluctuating attention is similar in PD dementia and DLB with parkinsonism. The current findings do not support the current arbitrary distinctions between these patient groups. Importantly, patients with PD do not experience fluctuating attention.

Aged↗
PubMed2002

The economic burden of coronary heart disease in the UK.

OBJECTIVE: To estimate the economic burden of coronary heart disease in the UK using both direct and indirect costs. DESIGN AND SETTING: A prevalence based approach was used to assess coronary heart disease related costs from the societal perspective. PATIENTS: All UK residents in 1999 with coronary heart disease (ICD 9 codes 410-414 and ICD10 codes I20-I25). MAIN OUTCOME MEASURES: Direct health care costs were estimated from spending on prevention, accident and emergency care, hospital care, rehabilitation, and drug treatment. Direct non-health service costs were estimated from data on informal care. "Friction period" adjusted productivity costs were estimated using the human capital approach from lost earnings attributable to coronary heart disease related mortality and morbidity. The friction period is the period of employees' absence from work before the employer replaces them with other workers. Failure to adjust for this factor would overstate production loss. RESULTS: Coronary heart disease cost pound 1.73 billion to the UK health care system in 1999: pound 2.42 billion in informal care and pound 2.91 billion in friction period adjusted productivity loss; 24.1% of production losses were attributable to mortality and 75.9% to morbidity. The total annual cost of all coronary heart disease related burdens was pound 7.06 billion, the highest of all diseases in the UK for which comparable analyses have been done. CONCLUSIONS: Coronary heart disease is a leading public health problem in the UK in terms of the economic burden from disease. Cost estimates would be substantially understated if informal care/productivity costs were excluded.

Absenteeism↗
PubMed2002

Estimating the relationship between disease progression and cost of care in dementia.

BACKGROUND: Previous studies have shown a positive relationship between disease severity and cost. AIMS: To explore the factors affecting time to institutionalisation and estimate the relationship between the costs of care and disease progression. METHOD: Retrospective analysis of a longitudinal data-set for a cohort of 100 patients diagnosed with Alzheimer's disease or vascular dementia. RESULTS: Changes in both Mini-Mental State Examination (MMSE) and Barthel scores have independent and significant marginal effects on costs. Each one-point decline in the MMSE score is associated with a pound sterling 56 increase in the four-monthly costs, whereas each one-point fall in the Barthel index is associated with a pound sterling 586 increase in costs. CONCLUSIONS: It may be inappropriate for economic models of disease progression in dementia to be based solely on measures of cognitive change. MMSE and the Barthel index are independent significant predictors of time to institutionalisation and cost of care, but changes in the Barthel index are particularly important in predicting costs outside institutional care.

Age Factors↗
PubMed2001

Randomised controlled trial of an interactive multimedia decision aid on hormone replacement therapy in primary care.

OBJECTIVE: To determine whether a decision aid on hormone replacement therapy influences decision making and health outcomes. DESIGN: Randomised controlled trial. SETTING: 26 general practices in the United Kingdom. PARTICIPANTS: 205 women considering hormone replacement therapy. INTERVENTION: Patients' decision aid consisting of an interactive multimedia programme with booklet and printed summary. OUTCOME MEASURES: Patients' and general practitioners' perceptions of who made the decision, decisional conflict, treatment choice, menopausal symptoms, costs, anxiety, and general health status. RESULTS: Both patients and general practitioners found the decision aid acceptable. At three months, mean scores for decisional conflict were significantly lower in the intervention group than in the control group (2.5 v 2.8; mean difference -0.3, 95% confidence interval -0.5 to -0.2); this difference was maintained during follow up. A higher proportion of general practitioners perceived that treatment decisions had been made "mainly or only" by the patient in the intervention group than in the control group (55% v 31%; 24%, 8% to 40%). At three months a lower proportion of women in the intervention group than in the control group were undecided about treatment (14% v 26%; -12%, -23% to -0.4%), and a higher proportion had decided against hormone replacement therapy (46% v 32%; 14%, 1% to 28%); these differences were no longer apparent by nine months. No differences were found between the groups for anxiety, use of health service resources, general health status, or utility. The higher costs of the intervention were largely due to the video disc technology used. CONCLUSIONS: An interactive multimedia decision aid in the NHS would be popular with patients, reduce decisional conflict, and let patients play a more active part in decision making without increasing anxiety. The use of web based technology would reduce the cost of the intervention.

Decision Making, Computer-Assisted↗
PubMed2001

Randomised controlled trial of an interactive multimedia decision aid on benign prostatic hypertrophy in primary care.

OBJECTIVE: To determine whether a decision aid on benign prostatic hypertrophy influences decision making, health outcomes, and resource use. DESIGN: Randomised controlled trial. SETTING: 33 general practices in the United Kingdom. PARTICIPANTS: 112 men with benign prostatic hypertrophy. INTERVENTION: Patients' decision aid consisting of an interactive multimedia programme with booklet and printed summary. OUTCOME MEASURES: Patients' and general practitioners' perceptions of who made the decision, decisional conflict scores, treatment choice and prostatectomy rate, American Urological Association symptom scale, costs, anxiety, utility, and general health status. RESULTS: Both patients and general practitioners found the decision aid acceptable. A higher proportion of patients (32% v 4%; mean difference 28%, 95% confidence interval 14% to 41%) and their general practitioners (46% v 25%; 21%, 3% to 40%) perceived that treatment decisions had been made mainly or only by patients in the intervention group compared with the control group. Patients in the intervention group had significantly lower decisional conflict scores than those in the control group at three months (2.3 v 2.6; -0.3, -0.5 to -0.1, P<0.01) and this was maintained at nine months. No differences were found between the groups for anxiety, general health status, prostatic symptoms, utility, or costs (excluding costs associated with the video disc equipment). CONCLUSIONS: The decision aid reduced decisional conflict in men with benign prostatic hypertrophy, and the patients played a more active part in decision making. Such programmes could be delivered cheaply by the internet, and there are good arguments for coordinated investment in them, particularly for conditions in which patient utilities are important.

Aged↗
PubMed2001

Targeting mutants of PTEN reveal distinct subsets of tumour suppressor functions.

The tumour suppressor protein PTEN (phosphatase and tensin homolog deleted on chromosome 10) is a lipid phosphatase which can antagonize the phosphoinositide 3-kinase (PI 3-kinase) signalling pathway, promoting apoptosis and inhibiting cell-cycle progression and cell motility. We show that very little cellular PTEN is associated with the plasma membrane, but that artificial membrane-targeting of PTEN enhances its inhibition of signalling to protein kinase B (PKB). Evidence for potential targeting of PTEN to the membrane through PDZ domain-mediated protein-protein interactions led us to use a PTEN enzyme with a deletion of the C-terminal PDZ-binding sequence, that retains full phosphatase activity against soluble substrates, and to analyse the efficiency of this mutant in different cellular assays. The extreme C-terminal PDZ-binding sequence was dispensable for the efficient down-regulation of cellular PtdIns(3,4,5)P3 levels and a number of PI 3-kinase-dependent signalling activities, including PKB and p70S6K. However, the PDZ-binding sequence was required for the efficient inhibition of cell spreading. The data show that a PTEN mutation, similar to those found in some tumours, affects some functions of the protein but not others, and implicate the deregulation of PTEN-dependent processes other than PKB activation in the development of some tumours. Significantly, this hypothesis is supported by data showing low levels of PKB phosphorylation in a glioblastoma sample carrying a mutation in the extreme C-terminus of PTEN compared with tumours carrying phosphatase-inactivating mutations of the enzyme. Our data show that deregulation of PKB is not a universal feature of tumours carrying PTEN mutations and implicate other processes that may be deregulated in these tumours.

Animals↗
PubMed2001

Counting the costs: comparing depot medroxyprogesterone acetate and norethisterone oenanthate utilisation patterns in South Africa.

BACKGROUND: In South Africa, where health care resources are limited, it is important to ensure that drugs provision and use is rational. The Essential Drug List includes depot medroxyprogesterone acetate (DMPA) and norethisterone oenanthate (NET-EN) as injectable progestagen-only contraceptives (IPCs), and both products are extensively used. OBJECTIVES AND METHODS: Utilisation patterns of the injectable contraceptive products DMPA and NET-EN are compared in the context of current knowledge of the safety and efficacy of these agents. Utilisation patterns were analysed by means of a Pareto (ABC) analysis of IPCs issued from 4 South African provincial pharmaceutical depots over 3 financial years. A case study from rural KwaZulu-Natal, South Africa, is used to examine utilisation patterns and self-reported side effects experienced by 187 women using IPCs. RESULTS: IPCs accounted for a substantial share of total state expenditure on drugs. While more DMPA than NET-EN was issued, NET-EN distribution from 2 depots increased over the 3-year period. Since DMPA was cheaper, if all NET-EN clients in the 1999/2000 financial year (annualised) had used DMPA, the 4 depots could have saved 4.95 million South African Rands on product acquisition costs alone. The KZN case study showed slightly more NET-EN (54%) than DMPA (46%) use; no significant differences in self-reported side effects; and that younger women were more likely to use NET-EN than DMPA (p = 0.0001). CONCLUSIONS: Providing IPCs on the basis of age is not appropriate or cost effective. Rational use of these products should include consideration of the cost of prescribing one over another.

Adolescent↗
PubMed2001

Evaluation of the safety and efficacy of repeated sedations for the radiotherapy of young children with cancer: a prospective study of 1033 consecutive sedations.

PURPOSE: A prospective observational study to examine our current practice of either conscious sedation (C.S.) or general anesthetic (G.A.) for children undergoing radiation therapy (we use the term sedation to include both C.S. and G.A.). Specifically, the study examines the reasons for selection of patients, choice of drugs, safety and effectiveness of the procedure, side effects of repeated daily sedation, and compliance of the family with the regimen. METHODS AND MATERIALS: Recorded data included patient demographics, sedation technique, time for various stages of the procedure, breathing support required, sedation outcome, and complications. RESULTS: One hundred ninety-eight consecutive children underwent 4232 procedures involving either simulation or radiation treatment, an average of 21 procedures each. Seventy-four (37%) required sedation for a total of 1033 procedures, an average of 14 sedations each. For those patients who received sedation, the age ranged from 9 months to 14 years (median, 3.8) and 96% had a mold, (85% of the head and neck). The doctor's assessment of the need for sedation was correct 89% of the time. Thirty-seven percent required sedation at the start of treatment, but, even after 30 fractions, 15% still required sedation. Presedation status correlated with successful sedation and treatment (p = 0.0001). Ninety-six percent had some form of i.v. access, usually a portacath (76%); 883 sedations were performed with G.A. and 148 with C.S.; 93% of sedations were completed satisfactorily, 5% with some difficulty, and the patient was unable to be treated in 2%. With G.A., satisfactory sedation was achieved 97% of the time, whereas, with C.S., satisfactory sedation was achieved only 68% of the time. There were no complications for 97% of observations. Not one serious complication occurred. An endotracheal tube was used only twice during G.A. For C.S., the results for chloral hydrate, meperidine, and midazolam were, respectively, at least one complication, 23%, 0%, 5%; satisfactory sedation for treatment, 60%, 60%, 82%; and unable to treat 20%, 13%, 5%. For G.A., only 1 patient was unable to be treated. The median time from start of medication to the end of radiation treatment was a median of 10 min (75% complete within 15 min) for G.A., vs. 30 min (75% complete in 50 min) for C.S. On multivariate analysis, the only significant factor predicting a successful outcome was a G.A. using propofol (odds ratio, 20.6), vs. C.S. using either chloral hydrate, meperidine, or midazolam. (p = 0.0001). CONCLUSION: In this study, there were no serious complications of sedation in 1033 procedures. As a result of the study, we developed improved methods for better preparation of the patient and family to try to reduce the need for sedation, and reduce the indications for C.S., while confirming the safety and efficacy of a G.A. with propofol for children needing sedation for daily radiation therapy.

Adolescent↗
PubMed2001

Attention and fluctuating attention in patients with dementia with Lewy bodies and Alzheimer disease.

BACKGROUND: Attentional deficits are described in the consensus clinical criteria for the operationalized diagnosis of dementia with Lewy bodies (DLB) as characteristic of the condition. In addition, preliminary studies have indicated that both attentional impairments and fluctuation of attentional impairments are more marked in patients with DLB than in patients with Alzheimer disease (AD), although neuropsychological function has not previously been examined in a large prospective cohort with confirmed diagnostic accuracy against postmortem diagnosis. METHODS: A detailed evaluation of attention and fluctuating attention was undertaken in 155 patients with dementia (85 with DLB and 80 with AD) from a representative hospital dementia case register and 35 elderly controls using the Cognitive Drug Research Computerized Assessment System for Dementia Patients computerized neuropsychological battery. Operationalized clinical diagnosis was made using the consensus criteria for DLB and the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria for AD. High levels of sensitivity and specificity have been achieved for the first 50 cases undergoing postmortem examination. RESULTS: The groups were well matched for severity of cognitive impairments, but the AD patients were older (mean age, 80 vs 78 years) and more likely to be female (55% vs 40%). Patients with DLB were significantly more impaired than patients with AD on all measures of attention and fluctuating attention (for all comparisons, t > or = 2.5, P<.001), and patients from both dementia groups were significantly more impaired than elderly controls for all comparisons other than cognitive reaction time, which was significantly more impaired in DLB patients than controls but was comparable in controls and AD patients. There were, however, significant associations between the severity of cognitive impairment and the severity of both attentional deficits and fluctuations in attention. CONCLUSIONS: This large prospective study confirms that slowing of cognitive processing, attention, and fluctuations of attention are significantly more pronounced in DLB and AD patients, although fluctuating attention is common in patients with moderate-to-severe AD. Deficits of cognitive reaction time appear to be specific to DLB, except in severe dementia. A detailed evaluation of attentional performance could make an important contribution to differential diagnosis, although the results need to be interpreted within the context of the overall severity of cognitive deficits.

Aged↗
PubMed2001

Cost-effectiveness analysis of intensive blood-glucose control with metformin in overweight patients with type II diabetes (UKPDS No. 51).

AIMS/HYPOTHESIS: To estimate the economic efficiency of intensive blood-glucose control with metformin compared with conventional therapy primarily with diet in overweight patients with Type II (non-insulin-dependent) diabetes mellitus. METHODS: Cost-effectiveness analysis based on patient level data from a randomised clinical controlled trial involving 753 overweight (> 120% ideal body weight) patients with newly diagnosed Type II diabetes conducted in 15 hospital-based clinics in England, Scotland and Northern Ireland as part of the UK Prospective Diabetes Study. Subjects were allocated at random to an intensive blood-glucose control policy with metformin (n = 342) or a conventional policy primarily with diet (n = 411). The analysis was based on the cost of health care resources associated with metformin and conventional therapy and the estimated effectiveness in terms of life expectancy gained from within-trial effects. RESULTS: Intensive blood-glucose control with metformin produced a net saving of 258 Pounds per patient (1997 United Kingdom prices) over the trial period (median duration of 10.7 years) due to lower complication costs, and increased life expectancy by 0.4 years (costs and benefits discounted at 6%). CONCLUSIONS/INTERPRETATION: As metformin is both cost-saving in the United Kingdom and extends life expectancy when used as first line pharmacological therapy in overweight Type II diabetic patients, its use should be attractive to clinicians and health care managers alike.

Adult↗
PubMed2001

Limitations of randomized clinical trials for evaluating emerging operations: the case of lung volume reduction surgery.

Although unanswered questions remain, scores of observational studies and several small randomized clinical trials (RCTs) indicate that lung volume reduction surgery (LVRS) offers safe and effective palliation for a relatively well defined subset of patients with advanced emphysema. Nonetheless, Medicare and other insurers stopped reimbursement for the procedure. Subsequently, two multicenter RCTs on LVRS, the National Emphysema Treatment Trial (NETT) and the Overholt-BlueCross Emphysema Surgery Trial (OBEST), were launched with the stipulation that the procedure would not be paid for outside these trials. Thus access to LVRS has been denied to patients who could benefit but do not wish to participate in an RCT. Emerging operations, unlike new drugs or devices, pass through evolutionary changes and frequently fail to produce data that meet the scientific rigor required by randomized studies. In such a setting, the observational approach is more appropriate. Indeed, almost all operations in the present surgical armamentarium have been evaluated and have evolved through observational studies without the use of RCTs. By the time new operations are standardized and qualify for RCTs, benefits for certain patients may be demonstrated and randomization could involve unacceptable health hazards. Patients from this population should be offered the choice between participating in RCTs and having the operation outside the study. Imposition of financial restrictions that bars access to a therapy with known benefit is a questionable practice.

Bias↗