Search PubMed⌕ Search

Biomedical subjects

H A Llewellyn-Thomas

Publications and source records attributed to H A Llewellyn-Thomas.

At least 19 recordsLinked to original sources
PubMed2003

Hormone replacement therapy after treatment for breast cancer: physicians' attitudes towards randomized trials.

PURPOSE: Physician support is required for successful patient recruitment to a large randomized controlled trial (RCT) designed to determine the safety and benefits of short-term hormone replacement therapy (HRT) after breast cancer (BC). METHODS: A survey was mailed to 1899 Canadian gynaecologists, family physicians, medical, radiation and surgical oncologists to assess willingness to refer patients to an RCT of HRT after BC. RESULTS: Of 538 physicians, 420 (78%) reported that they would be willing to refer a woman after BC to an RCT of HRT versus placebo. Variables predicting willingness to refer included: support for HRT in well women (p = 0.04) and after BC (p = 0.0001); support for clinical trials (p = 0.0001); ongoing BC trials at the physicians' institution (p = 0.003); currently prescribing HRT to women after BC (p = 0.03); and beneficial results in ongoing RCTs of HRT in well women (p = 0.02). CONCLUSIONS: An RCT of short-term HRT after BC may be feasible among Canadian physicians.

Antineoplastic Agents, Hormonal↗
PubMed2000

Randomized, controlled trial of an interactive videodisc decision aid for patients with ischemic heart disease.

OBJECTIVE: To determine the effect of the Ischemic Heart Disease Shared Decision-Making Program (IHD SDP) an interactive videodisc designed to assist patients in the decision-making process involving treatment choices for ischemic heart disease, on patient decision-making. DESIGN: Randomized, controlled trial. SETTING: The Toronto Hospital, University of Toronto, Toronto, Ontario, Canada. PARTICIPANTS: Two hundred forty ambulatory patients with MEASUREMENTS AND MAIN RESULTS: The primary outcome was patient satisfaction with the decision-making process. This was measured using the 12-item Decision-Making Process Questionnaire that was developed and validated in a randomized trial of the benign prostatic hyperplasia SDP. Secondary outcomes included patient knowledge (measured using 20 questions about knowledge deemed necessary for an informed treatment decision), treatment decision, patient-angiographer agreement on decision, and general health scores. Outcomes were measured at the time of treatment decision and/or at 6 months follow-up. Shared decision-making program scores were similar for the intervention and control group (71% and 70%, respectively; 95% confidence interval [CI] for 1% difference, -3% to 7%). The intervention group had higher knowledge scores (75% vs 62%; 95% CI for 13% difference, 8% to 18%). The intervention group chose to pursue revascularization less often (58% vs 75% for the controls; 95% CI for 17% difference, 4% to 31%). At 6 months, 52% of the intervention group and 66% of the controls had undergone revascularization (95% CI for 14% difference, 0% to 28%). General health and angina scores were not different between the groups at 6 months. Exposure to the IHD SDP resulted in more patient-angiographer disagreement about treatment decisions. CONCLUSIONS: There was no significant difference in satisfaction with decision-making process scores between the IHD SDP and usual practice groups. The IHD SDP patients were more knowledgeable, underwent less revascularization (interventional therapies), and demonstrated increased patient decision-making autonomy without apparent impact on quality of life.

Confidence Intervals↗
PubMed2000

The management of asthma: a case-scenario-based survey of family physicians and pulmonary specialists.

This study assessed family physicians' and pulmonary specialists' approaches to the treatment of adult outpatient asthma using a self-administered questionnaire consisting of six asthma scenarios of varying severity levels. One hundred sixty-three randomly selected family physicians and pulmonary specialists completed the questionnaire (response rate of 80%). We observed that, regardless of asthma severity, more than 75% of physicians (regardless of specialty) would not include oral theophylline or nonsteroidal anti-inflammatory preparations in their treatment approach. Pulmonary specialists' and family physicians' approaches to mild asthma were similar (more than 90% recommended an inhaled beta2-agonist). However, considerable differences existed among and between physician groups for the remaining scenarios. For example, with an exacerbation associated with an upper respiratory tract infection, family physicians were more likely to recommend oral antibiotics (p<0.0001) and a same-day outpatient visit (p<0.0001), whereas specialists were more likely to increase the inhaled corticosteroid dosage (p<0.0001). Overall, disagreement was observed almost twice as often among family physicians than among specialists. Our results suggest that physicians vary markedly in their reported use of most interventions available to treat asthma, even when the disease severity is specified.

Adult↗
PubMed1999

Physicians' approaches to providing asthma education to patients and the level of patient involvement in management decisions.

The objectives of this study were to describe physicians' self-reported approaches to providing disease-specific education to adults with asthma in an outpatient setting and their opinions about the level of patient involvement in management decisions. A mailed questionnaire was completed by 163 randomly selected physicians, representing an 80% response rate. The educational actions provided most frequently included information about prescribed medications (90%-100% of physicians), general asthma information (87%-98%), and inhaler demonstration (85%-95%). Educational activities provided least frequently were action plans (7%-74%) and referral to a nonprofit community asthma organization for further information (18%-36%). The reported provision of asthma education was related to patients' asthma severity (p < 0.0001) and physician specialty (p < 0.005). Physicians indicated that their patients were less involved in asthma management decisions than they would prefer (p < 0.001). The results suggest that physicians vary markedly in their approaches to providing asthma education to patients. Future descriptive and intervention studies are needed to identify the most effective models for providing education and patient involvement.

Adult↗
PubMed1998

In the queue for total joint replacement: patients' perspectives on waiting times. Ontario Hip and Knee Replacement Project Team.

We assessed patients on the waiting lists of a purposive sample of orthopaedic surgeons in Ontario, Canada, to determine patients' attitudes towards time waiting for hip or knee replacement. We focused on 148 patients who did not have a definite operative date, obtaining complete information on 124 (84%). Symptom severity was assessed with the Western Ontario/McMaster Osteoarthritis Index and a disease-specific standard gamble was used to elicit patients' overall utility for their arthritic state. Next, in a trade-off task, patients considered a hypothetical choice between a 1-month wait for a surgeon who could provide a 2% risk of post-operative mortality, or a 6-month wait for joint replacement with a 1% risk of post-operative mortality. Waiting times were then shifted systematically until the patient abandoned his/her initial choice, generating a conditional maximal acceptable wait time. Patients were divided in their attitudes, with 57% initially choosing a 6-month wait with a 1% mortality risk. The overall distribution of conditional maximum acceptable wait time scores ranged from 1 to 26 months, with a median of 7 months. Utility values were independently but weakly associated with patients' tolerance of waiting times (adjusted R-square = 0.059, P = 0.004). After splitting the sample along the median into subgroups with a relatively 'low' and 'high' tolerance for waiting, the subgroup with the apparently lower tolerance for waiting reported lower utility scores (z = 2.951; P = 0.004) and shorter times since their surgeon first advised them of the need for surgery (z = 3.014; P = 0.003). These results suggest that, in the establishment and monitoring of a queue management system for quality-of-life-enhancing surgery, patients' own perceptions of their overall symptomatic burden and ability to tolerate delayed relief should be considered along with information derived from clinical judgements and pre-weighted health status instruments.

Adult↗
PubMed1997

Physicians' opinions about decision aids for patients considering systemic adjuvant therapy for axillary-node negative breast cancer.

PURPOSE: To examine variations in physicians' opinions about the appropriateness and content of decision aids for women with breast cancer and criteria for their evaluation. METHODS: Cross-sectional survey of all 144 Ontario oncologists by Dillman's mailed survey design. The response rate was 87%. RESULTS: The predominant current practice pattern was to spontaneously inform patients about the treatment recommendations, degree of certainty regarding the recommendations, treatment regime, benefits and side effects. Most respondents (94%) endorsed patient decision aids, particularly when there was high uncertainty about providing adjuvant treatment. Over three-quarters endorsed measuring the following outcomes of decision aids: patients' clarity of trade-offs involved (e.g. survival vs. side effects); comprehension of treatment alternatives, risks and benefits; accuracy of expectations; decision satisfaction; anxiety; commitment to the decision; length of time to complete the decision aid; and decision uncertainty. The least support was for the use of the decision itself as an outcome measure. CONCLUSIONS: There is considerable consensus regarding the indications for, content and criteria for evaluating decision aids which should be considered when developing aids relevant to the needs of clinicians and patients.

Adult↗
PubMed1997

Breast cancer patients' attitudes about rationing postlumpectomy radiation therapy: applicability of trade-off methods to policy-making.

PURPOSE: Along with evidence, clinical policies must take patients' values into account. Particularly where evidence is limited and where assumptions of utility-maximizing behavior may not be valid, new methods such as trade-off techniques (TOTs), which allow elicitation of patients' treatment alternatives, might be useful in policy formulation. We used TOTs to assess breast cancer patients' attitudes toward two clinical policies designed to ration adjuvant postlumpectomy breast radiation therapy. METHODS: Cross-sectional interviews were performed in a tertiary cancer center. A total of 102 patients were presented with information about the side effects and benefits associated with two hypothetical decisions: (1) willingness to receive treatment elsewhere to shorten the wait for radiation therapy, and (2) foregoing radiation therapy in the face of small marginal benefits. For each scenario, a TOT was used to identify the maximal acceptable wait time (MAWT) for therapy and the benefit threshold at which the patient would forego therapy. Associations of clinical and demographic factors with these decisions were determined by regression analysis. RESULTS: Patients would be willing to wait, on average, 7 weeks before wanting to leave their city for radiation therapy, less than the 13-week delay our patients actually faced. Older patients were less willing to wait (P = .013); 46% of patients would not give up radiation therapy, even in the face of no stated benefit. Willingness to give up radiation therapy was predicted by willingness to accept delay (odds ratio [OR], 1.84; 95% confidence interval [CI], 1.05 to 3.37) and being employed (OR, 2.61; 95% CI, 1.08 to 6.54). Patients with larger tumors were less willing to give up radiation therapy (OR, 0.57; 95% CI, 0.31 to 0.97). CONCLUSION: Even in difficult decisions such as rationing postlumpectomy breast cancer radiation therapy, TOTs can inform policy formulation by indicating the distributions of patients' preferences.

Adult↗
PubMed1997

Investigating patients' preferences for different treatment options.

This paper provides an overview of two methodologic approaches to investigating patients' treatment preferences. The first approach is derived from formal decision analysis, and is widely advocated for formulating health policy and constructing clinical guide-lines. The author argues that it may not be suitable for application in the context of individuals' decisional behaviour, and then describes the conceptualization, development, and application of an alternative approach to quantifying patients' relative treatment preferences. The approach--the "probability trade-off"--can be structured to illustrate in a highly graphic way the actual complex dilemmas patients often face, and its procedures can be arranged so as to engage the patient in explicitly considering the trade-offs involved. Given these visual and interactive characteristics, and its performance to date, the probability trade-off seems to be a particularly promising technique not only for incorporating patients' preferences into the design of clinical trials, but also for helping patients to comprehend important probabilistic information and then use that information to clarify and communicate their values to the health-care team. The future phases of this cumulative work will be devoted to testing hypotheses that the probability trade-off technique actually can fulfil this function.

Choice Behavior↗
PubMed1995

Presenting clinical trial information: a comparison of methods.

The study objective was to assess the relative effects of 2 approaches to teaching about a clinical trial, in terms of patients' satisfaction, information understanding, and whether or not they would enter such a trial. One hundred patients receiving radiation therapy for a variety of cancer diagnoses were randomized to receive information about a hypothetical trial, either by audio tape or interactive computer program. A day later, information understanding was assessed. One week later, method satisfaction and whether respondents would enter such a trial were assessed. There were no differences in understanding or satisfaction. Members of the computer program group tended to report a more positive attitude towards trial entry (chi 2 = 4.0; 1 df; P = 0.05). Overall, refusers tended to be women with higher understanding scores. The results suggest that teaching with interactive components might not adversely affect trial accrual. Further work involving an actual trial entry decision is merited; the sex of the respondent should be controlled in designing this future work.

Clinical Trials as Topic↗
PubMed1995

Appropriateness of adjuvant systemic therapy for axillary node-negative breast cancer: a physician opinion survey.

PURPOSE: To examine variations in physicians' recommendations for systemic adjuvant therapy in the treatment of women with node-negative breast cancer (NNBC) and to determine factors used in making specific recommendations. MATERIALS AND METHODS: A questionnaire was sent by mail to all 149 Ontario physicians who actively treated breast cancer in 1993. The questionnaire described 48 clinical scenarios of women with NNBC, which included all possible combinations of the following factors: menopausal status, tumor size, hormone receptor status, histologic and nuclear grade, and lymphatic and/or vascular invasion. Respondents rated the appropriateness of administering tamoxifen, combination chemotherapy, or both tamoxifen and combination chemotherapy on a nine-point scale from extremely inappropriate to extremely appropriate. Respondent agreement and disagreement were tabulated for each scenario, and factors associated with specific treatment ratings were analyzed by logistic regression. RESULTS: The response rate was 87%. Agreement for the appropriateness of specific therapies was most evident where clinical trials have demonstrated efficacy, whereas disagreement was observed in scenarios in which support for a specific treatment is not available in the current literature. Relevant tumor- and patient-specific factors were used in decision-making; personal characteristics of the respondents had no statistically significant impact on appropriateness ratings. CONCLUSION: The physicians surveyed had good knowledge of NNBC prognostic factors, but had a range of opinion on optimal therapy for many clinical scenarios, which reflects current knowledge of the benefits of adjuvant therapy for NNBC.

Adult↗
PubMed1994

Can there be a more patient-centred approach to determining clinically important effect sizes for randomized treatment trials?

Sample sizes for treatment trials with categorical outcomes are conventionally derived by balancing three elements: a difference between alternative treatments in the event rates for the outcomes of interest (commonly termed the clinically important difference), the alpha error tolerance (false positive risk) and the beta error tolerance (false negative risk). Clinically important differences used to plan trials are chosen in part based on earlier experience with similar interventions (i.e. biological or clinical plausibility). Methodological conventions and clinicians' perceptions will also affect choices. Lastly, practical concerns about the feasibility of accruing large numbers of subjects may drive trialists to specify bigger differences as clinically important, with a view to containing sample size requirements. We suggest that patients or other members of the public be given an active role in determining the magnitude of the clinically important treatment effect for trial planning. Probability trade-offs could be constructed to enable patients and/or healthy volunteers to indicate the degree of benefit they would want from a "new" treatment, given the potential side-effects of the same treatment. This method has the advantage of respecting patient autonomy and principles of informed consent. It provides an additional consideration when plausible effect sizes and error tolerances on hypothesis tests are balanced against feasibility of accruing various sample sizes. Its primary disadvantage is inconvenience, as it adds another step to trial design. On the other hand, if patient-based clinically important differences are generated for a variety of disease states and types of treatments, specific trade-off exercises may be needed only for unusual trials.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1993

Do patients' evaluations of a future health state change when they actually enter that state?

Fundamental to using utilities for future health states for clinical decision analysis is the assumption that the utilities are stable. The purpose of this study was to determine if cancer patients' prior evaluations of a treatment-induced health state remain stable when they later experience that state. Before a four-week course of radiation therapy, 66 laryngeal cancer patients evaluated three common treatment-induced outcome scenarios (mild/moderate/severe) using rating scales and the time trade-off, and provided self-assessments of voice symptoms, voice function, and general health. Evaluations and self-assessments were repeated at the end of therapy, and respondents indicated which outcome scenario described their actual end-of-therapy state. Twenty-four patients identified the mild scenario as their outcome state, 36 the moderate, and 6 the severe. No across-time differences in evaluations were detected, although significant (P < .0001) downward shifts in scores for voice symptoms (t = 5.67), voice function (t = 5.10), and general health (t = 6.69) indicated that actual change in health status had occurred. These results imply that patients' evaluations of imagined short-term health states encountered during radiation therapy for laryngeal cancer remain consistent when those states are experienced at a later time. The design of this project provides a model for determining if this consistency appears in other clinical situations.

Activities of Daily Living↗
PubMed1991

Patients' willingness to enter clinical trials: measuring the association with perceived benefit and preference for decision participation.

Patients who agree and those who refuse clinical trial entry may differ in attitudes towards decision control and the benefits associated with the trial arms. These differences, if they exist, have implications for the process of obtaining informed consent and for the generalization of the results of a clinical trial. This paper describes the development and initial application of methods designed to detect such differences. Developmental work involved creating an inventory of instruments designed to determine patients' attitudes towards participating in treatment decision making, permitting random selection of treatment, and undertaking the risks and benefits associated with the various treatments in a trial. Initial application involved modifying these instruments in terms of an actual chemotherapeutic trial for colonic adenocarcinoma, seeking responses to these measures from 60 non-eligible colorectal cancer patients, then determining whether those who would agree to trial entry differed systematically on these measures from those who indicated that they would refuse such a trial. Twenty-five of the respondents reported that, if faced with the actual decision, they would agree to trial entry: 35 would refuse. Refusers demanded more participation in decision making (Chi-square; P = 0.01) and a greater increment in treatment benefit (t-test; P = 0.0001). Twenty-two of the 35 refusers reported aversion to randomization as their primary reason for trial refusal. Since their particular content can be modified, these measures may be applicable to all clinical trials. They could be used to study the reasons patients accept or refuse trial entry and to determine if agreer-refuser attitude differences undermine the generalizability of a trials results.

Clinical Trials as Topic↗
PubMed1991

Use of written cases to study factors associated with regional variations in referral rates.

The major purpose was to explore the use of written case scenarios to investigate factors associated with regional variations in referral for consultation. Data were collected in Nova Scotia, where extensive computer-based records of utilization of health services are kept, and the nine health care regions are in sufficient proximity to make visits and interviews feasible. Interviews with 9 x 25 = 225 randomly-selected family physicians, using scenarios analogous to ICD-9 codes, permitted testing of hypotheses about the effects of selected variables on referral rates for hypothetical cases. The family physicians' self-reported referral behavior for the written case scenarios was compared, region by region, with the actual referral of analogous cases by physicians in the same region, as determined from Nova Scotia Health Services and Insurance Commission records. The results indicated that written scenarios provide a useful tool for studies of such variables. Generally, the family physicians responded appropriately to the information that described the hypothetical patients ("case cues"). However, comparisons of hypothetical and actual referral rates indicated that appropriate information about the environment within which referral decisions take place ("environmental cues") may be needed to explain actual regional variations in referral rates.

Attitude of Health Personnel↗