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PubMed2005

Keep people informed or leave them alone? A suggested tool for identifying research participants who rightly want only limited information.

People taking part in research vary in the extent to which they understand information concerning their participation. Since they may choose to limit the time and effort spent on such information, lack of understanding is not necessarily an ethical problem. Researchers who notice a lack of understanding are in the quandary of not knowing whether this is due to flaws in the information process or to participants' deliberate choices. We argue that the two explanations call for different responses.A tool for identifying those research participants who want limited information is presented. This consists of a restricted number of questions about trust in and appraisal of research, priority of time and privacy, and perception of a duty to participate. It is argued that an important group of participants who purposely lack understanding of the study can be identified with this tool. Some limitations to this approach are also discussed.

Biomedical Research↗
PubMed2002

Classical and Bayesian inference in neuroimaging: applications.

In Friston et al. ((2002) Neuroimage 16: 465-483) we introduced empirical Bayes as a potentially useful way to estimate and make inferences about effects in hierarchical models. In this paper we present a series of models that exemplify the diversity of problems that can be addressed within this framework. In hierarchical linear observation models, both classical and empirical Bayesian approaches can be framed in terms of covariance component estimation (e.g., variance partitioning). To illustrate the use of the expectation-maximization (EM) algorithm in covariance component estimation we focus first on two important problems in fMRI: nonsphericity induced by (i) serial or temporal correlations among errors and (ii) variance components caused by the hierarchical nature of multisubject studies. In hierarchical observation models, variance components at higher levels can be used as constraints on the parameter estimates of lower levels. This enables the use of parametric empirical Bayesian (PEB) estimators, as distinct from classical maximum likelihood (ML) estimates. We develop this distinction to address: (i) The difference between response estimates based on ML and the conditional means from a Bayesian approach and the implications for estimates of intersubject variability. (ii) The relationship between fixed- and random-effect analyses. (iii) The specificity and sensitivity of Bayesian inference and, finally, (iv) the relative importance of the number of scans and subjects. The forgoing is concerned with within- and between-subject variability in multisubject hierarchical fMRI studies. In the second half of this paper we turn to Bayesian inference at the first (within-voxel) level, using PET data to show how priors can be derived from the (between-voxel) distribution of activations over the brain. This application uses exactly the same ideas and formalism but, in this instance, the second level is provided by observations over voxels as opposed to subjects. The ensuing posterior probability maps (PPMs) have enhanced anatomical precision and greater face validity, in relation to underlying anatomy. Furthermore, in comparison to conventional SPMs they are not confounded by the multiple comparison problem that, in a classical context, dictates high thresholds and low sensitivity. We conclude with some general comments on Bayesian approaches to image analysis and on some unresolved issues.

Algorithms↗
PubMed1987

Empirical Bayes estimates of age-standardized relative risks for use in disease mapping.

There have been many attempts in recent years to map incidence and mortality from diseases such as cancer. Such maps usually display either relative rates in each district, as measured by a standardized mortality ratio (SMR) or some similar index, or the statistical significance level for a test of the difference between the rates in that district and elsewhere. Neither of these approaches is fully satisfactory and we propose a new approach using empirical Bayes estimation. The resulting estimators represent a weighted compromise between the SMR, the overall mean relative rate, and a local mean of the relative rate in nearby areas. The compromise solution depends on the reliability of each individual SMR and on estimates of the overall amount of dispersion of relative rates over different districts.

Age Factors↗
PubMed2001

A measure of informed choice.

OBJECTIVE: To develop a measure of informed choice. CONCEPTUALIZATION AND MEASUREMENT: The measure is based on the following definition of an informed choice: one that is based on relevant knowledge, consistent with the decision-maker's values and behaviourally implemented. The measure comprises an eight-item scale of knowledge, a four-item scale assessing attitudes towards undergoing the screening test and a record of test uptake. PARTICIPANTS: Sixty-six women awaiting their first antenatal clinic appointments. MEASURE DEVELOPMENT: In women offered a screening test in pregnancy, the internal reliability of both the knowledge and the attitude scales was acceptable (alpha coefficients 0.82 and 0.83, respectively). Of the 42 women completing both scales, 18 were classified as having made an informed choice, and 24 were classified as having made an uninformed choice. CONCLUSION: The results of this preliminary study provide some evidence to support the feasibility of conceptualizing and measuring informed choices regarding screening using a brief measure assessing knowledge and attitudes. The validity and utility of this approach awaits further studies, involving larger numbers of participants, offered different screening tests.

Decision Making↗
PubMed1998

HIV testing for HIV prevention: a comparative analysis of policies in Britain, Hungary and Sweden.

This paper compares policies on named HIV testing in the context of HIV prevention in Britain, Hungary and Sweden, and considers the extent to which these policies are based on evidence of effectiveness or on other, more contextual, factors. In Britain, testing has not featured significantly as a prevention strategy, and named testing has generally been carried out only with the voluntary, informed consent of individuals. In Hungary, testing is central to HIV prevention, and is required by law of certain groups. HIV testing is carried out mainly on a voluntary basis in Sweden, but, unlike in Britain, it has been actively promoted by public health authorities. The paper contrasts the 'right not to know' one's HIV status which is widely respected in Britain, with the 'responsibility to find out' which is more pervasive in Hungary and Sweden. Although policy makers in all three countries appear convinced that their's is the right approach, there appears to be as yet a dearth of convincing evidence to support their arguments.

Communicable Disease Control↗
PubMed2004

Diagnostic approach to dyspepsia.

The optimal diagnostic approach to the dyspeptic patient in primary care is still debated. Early endoscopy continues to be the diagnostic gold standard but competing non-invasive strategies challenge this. The most important approaches are empiric antisecretory treatment reserving endoscopy for unresponsive patients and patients with an early symptomatic relapse and helicobacter-based strategies reserving endoscopy for infected patients (test-and-scope) or for failures after eradication therapy (test-and-treat). Early endoscopy is recommended in patients with alarm features and should be considered in patients with new onset dyspepsia after age 50. In the remaining patients, early investigation can only be recommended in areas providing endoscopy at a low cost and with a short waiting list. The test-and-scope strategy may lead to a rise in the referral rates for endoscopy and cannot be recommended. The test-and-treat strategy is well documented in clinical trials as a safe and cost-effective approach. Helicobacter-based strategies are challenged by a decreasing prevalence of peptic ulcer disease and of the infection. In the near future, the empirical acid inhibition strategy will probably be cost-effective as gastro-oesophageal reflux becomes the predominant disorder in dyspeptic patients.

Anti-Bacterial Agents↗
PubMed2005

An overview of methods and empirical comparison of aggregate data and individual patient data results for investigating heterogeneity in meta-analysis of time-to-event outcomes.

Combining the results of individual studies using meta-analysis may be undertaken using either aggregate data (AD) or individual patient data (IPD). In any meta-analysis it is important to consider statistical heterogeneity between studies. Potential sources of heterogeneity can be explored using regression models with either AD or IPD. An overview of approaches and empirical assessment of how the results and conclusions differ from these analyses is undertaken using a meta-analysis of five randomized controlled trials comparing two antiepileptic drugs with time-to-event outcomes. Alternative meta-regression models using AD are compared to stratified Cox regression models using IPD. Age as a potential cause of heterogeneity is detected by both AD and IPD regression models. Time from first ever seizure to randomization is only identified by some AD models. A more thorough explanation of heterogeneity is obtained from the model using IPD but further empirical evidence comparing IPD and AD results are needed.

Clinical Trials as Topic↗
PubMed2006

Quality optimised analysis of general paired microarray experiments.

In microarray experiments, several steps may cause sub-optimal quality and the need for quality control is strong. Often the experiments are complex, with several conditions studied simultaneously. A linear model for paired microarray experiments is proposed as a generalisation of the paired two-sample method by Kristiansson et al. (2005). Quality variation is modelled by different variance scales for different (pairs of) arrays, and shared sources of variation are modelled by covariances between arrays. The gene-wise variance estimates are moderated in an empirical Bayes approach. Due to correlations all data is typically used in the inference of any linear combination of parameters. Both real and simulated data are analysed. Unequal variances and strong correlations are found in real data, leading to further examination of the fit of the model and of the nature of the datasets in general. The empirical distributions of the test-statistics are found to have a considerably improved match to the null distribution compared to previous methods, which implies more correct p-values provided that most genes are non-differentially expressed. In fact, assuming independent observations with identical variances typically leads to optimistic p-values. The method is shown to perform better than the alternatives in the simulation study.

Animals↗
PubMed1981

Some considerations bearing on the doctrine of self-fulfilling prophecy in sex chromosome aneuploidy.

The doctrine of self-fulfilling prophecy has been invoked in studies of the effects of sex chromosome aneuploidy on human development as a reason for routine concealment of the diagnosis from affected children and their families. It has been assumed that knowledge of the existence of risk for deviance from normal development automatically creates a self-defeating emotional climate. This communication attempts to delineate both advantageous and deleterious aspects of self-fulfilling prophecy in the medical management of sex chromosome aneuploidy, present at alternative approach, and reviews the experience in a prospective study of 52 families where a policy of disclosure was followed.

Aneuploidy↗
PubMed1996

Surgical patients' attitudes regarding participation in clinical anesthesia research.

We designed a questionnaire to identify the factors influencing both day of admission surgery (DAS) and ambulatory (AMB) patients in their decision whether to participate in and give informed consent for clinical anesthesia research. On the day of surgery, 276 patients were approached to complete a questionnaire and a visual analog scale (VAS) to assess anxiety. The data collected were observational and are presented as percentages for each group (DAS and AMB). One hundred eighty-two patient (60 DAS and 122 AMB) completed questionnaires. Both DAS and AMB patients desired 20-30 min to read a consent form. Preferred conditions for enrollment by both groups were as follows: interview at the time of preadmission testing; after consulting with their physician; in a private setting while dressed in street clothes; and with assurance that the investigator would also participate in the study, if eligible. Unacceptable conditions were as follows: research associated with any risk and interview in the operating room holding area. All patients responded that they were capable of making the decision whether to participate in research on the day of surgery. Most AMB and DAS patients found it acceptable to be recruited on the day of surgery, if approached appropriately.

Adult↗
PubMedDate not supplied

The impact of the introduction of the ethical review process for research using animals in the UK: attitudes to alternatives among those working With experimental animals.

A postal questionnaire survey was carried out in late 1999 of those involved in working under the Animals (Scientific Procedures) Act 1986, namely the Certificate Holders, Project Licence Holders, Personal Licence Holders, Named Veterinary Surgeons, and Named Animal Care and Welfare Officers. The aim of the survey was to elicit views on the effectiveness of the introduction of the Ethical Review Process (ERP), introduced in April 1999. This report covers issues related to the use of alternatives, which were incorporated into the questionnaires. The number of returned questionnaires (45% of 1636 questionnaires) was sufficient for a meaningful analysis to be made of attitudes to the use of alternatives. In response to questions about the reason for the use of alternatives, more than 80% answered that alternatives should be used on moral or ethical grounds. Only about 50% of Certificate Holders and Licence Holders answered that alternatives were used because of legal requirements. Most respondents believed that replacement alternatives did not provide scientific information of equivalent value to that obtained from animal experiments. However, the majority also believed that it was possible to carry out valid scientific experiments by using replacement alternatives. The majority of Named Animal Care and Welfare Officers believed that the ERP had improved many aspects of refinement alternatives. In particular the "culture of care" had improved. Most establishments had a formal mechanism for discussing alternatives, although it was noteworthy that relatively few Personal Licence Holders believed this to be the case. In general, the majority of those working under the 1986 Act and most establishments seem to have a positive approach to the use of alternatives.

Animal Testing Alternatives↗
PubMed2004

Euthanasia education for health professionals in Turkey: students change their opinions.

The purpose of this study was to investigate the impact of euthanasia education on the opinions of health sciences students. It was performed among 111 final year students at the College of Health Sciences, Dokuz Eylül University, Izmir, Turkey. These students train to become paramedical professionals and health technicians. Fifteen hours of educational training concerning ethical values and euthanasia was planned and the students' opinions about euthanasia were sought before and after the course. Statistical analyses of the data were performed with the related samples t-test by means of the Epi-Info program. Significant changes were shown in the students' opinions on people's right to decide about their own life, euthanasia in unconscious patients, and reasons for their objection to euthanasia after completing the course. The results of this study suggest that education can significantly change a person's approach to euthanasia.

Adult↗
PubMed1995

Information and decision-making preferences of men with prostate cancer.

PURPOSE/OBJECTIVES: To determine whether a relationship exists between preferences for involvement in decision making and type of information in patients with cancer. DESIGN: Survey, correlational. SETTING: Community urology clinic in Winnipeg, Manitoba, Canada. SAMPLE: Convenience sample of 57 men (mean age of 71 years). METHODS: Subjects completed a card sort to elicit their preferred role in treatment decision making. A two-part questionnaire measured the type and amount of information preferred. FINDINGS: The majority (57.9%) of men preferred a passive decision-making role. Information on disease advancement, likelihood of cure, and types of treatment available were the three preferred categories of information. Men in the collaborative group and those who wanted their physician to make treatment decisions-only after seriously considering their opinions-also wanted significantly more information in these three categories. Married men ranked self-care information as significantly less important than did single men. Information preferences were similar regardless of preferred decision-making role. CONCLUSIONS: Although the majority of men in this sample wanted their physician to make final treatment decisions, they did want to be informed. Information preferences were similar to other groups of patients with cancer. Future clinical studies are required to determine if providing these men with more information will enable them to assume a more active decision-making role. IMPLICATIONS FOR NURSING PRACTICE: Given the small variance in decision-making and information preferences accounted for by sociodemographic and treatment/disease-related factors, individual assessment of these preferences remains the best clinical approach.

Aged↗
PubMed2006

Adaptation of the WHO guideline for residual DNA in parenteral vaccines produced on continuous cell lines to a limit for oral vaccines.

Although there is a WHO guidance for a limit on residual DNA for parenterally administered vaccines produced on continuous cell lines, there is no corresponding guidance for oral vaccines. To help determine an oral limit, we performed a study of Vero cell DNA uptake in rats, in which the relative uptake and persistence of Vero cell DNA administered orally was compared to its uptake when delivered intramuscularly (IM). The results of this study allowed the generation of an empirically derived IM versus oral factor (10(6)) representing the relative inefficiency of DNA uptake by oral administration. This factor was then applied to the WHO recommended parenteral limit of 10 ng/dose to determine a corresponding upper limit on the level of residual Vero cell DNA for an oral vaccine of 10 mg. As a conservative approach, this empirically determined limit was reduced 100-fold to 100 microg. Thus, the results of this animal study, together with additional evidence in the literature, support a residual DNA safety limit of 100 microg per dose for an oral vaccine produced on a continuous cell line.

Administration, Oral↗
PubMed2000

When expertise and ethics diverge: lay and professional evaluation of psychotherapists in Israel.

Do psychotherapists' unethical practices influence how they are perceived? The 202 Israeli lay and professional psychology participants rated systematically varied descriptions of effective therapists and potential clients under conditions of no difficulties (standard), practice without a license, and a previous sexual boundary violation on indexes of evaluation and willingness to refer. Participants completed a measure of important variables in therapist selection. Effective standard therapists were rated most favorably, unlicensed therapists were rated favorably, and therapists who violated sexual boundaries in the past were rated least favorably. When results were analyzed by respondent characteristics, laypersons rated unlicensed professionals (p < .01) and sexual boundary violators (p < .0001) more positively than did clinical psychologists. Men rated the violators more favorably than did women (p < .05). Factor analysis of therapist selection measures identified professional and personal factors, but only the former were associated with ratings of "problem" therapists. The results underscore the gap between ethical standards and applied decisions made by professionals and laypersons. Further investigation is needed to ensure quality care in both professional and consumer approaches to psychotherapy.

Attitude of Health Personnel↗
PubMed2004

Nursing care of elderly people at home and ethical implications: an experience from Istanbul.

Elderly people are a particularly vulnerable group in society and have special health problems. The world population of older people is increasing. People who are 65 years or older constitute 6% of the Turkish population, 90% of whom have chronic health problems. In Turkey, there is a high possibility that elderly people's requirements are not met by today's health care system in the way they would wish. They prefer not to be hospitalized when they have health problems. From a wider perspective, various countries are still seeking how to provide the best care for elderly people. Our goal was to characterize home-based care for elderly people using an ethical approach as an area of interest for nurses and other health care professionals now and in the future, both for Turkey specifically and from a global perspective. We studied four case histories and then prepared a composite scenario and a short questionnaire for elderly people living in a specific district of Istanbul to evaluate their expectations from the health care system. We compared our findings with situations in other countries and have proposed some practical solutions. The results showed that these older people preferred to receive nursing care at home instead of in hospital in Turkey, and also in many other countries. In this article we discuss our findings, comparing them with those in the literature, and suggest that there should be nursing care at home with insurance coverage while using a proper ethical approach.

Aged↗