Communicating probabilistic information to cancer patients: is there 'noise' on the line?

Decisional involvement and information preferences of patients with hematologic malignancies

Understanding decisional involvement and information preferences in patients with hematologic malignancies may help to optimize physician-patient communication about treatment decisions and align the decision-making processes with patients' preferences. We described and examined factors associated with preferences of patients with hematologic malignancies for decisional involvement, information sources, and presentation of information. In a multicenter observational study, we recruited 216 patients with hematologic malignancies of any stage from September 2003 to June 2007. Patients were asked about their decisional involvement preferences (Control Preferences Scale), information sources (including most useful source of information), and preferences for their oncologists' presentation of treatment success information. We used multivariate logistic regressions to identify factors associated with decisional involvement preferences and usefulness of information sources (physicians vs nonphysicians). Patient-directed, shared, and physician-directed approaches were preferred in 34%, 38%, and 28% of patients, respectively. Physicians and computer/Internet were the most common information sources; 42% perceived physicians as the most useful source. On multivariate analysis, patients with less than a college education (vs postgraduate education) were less likely to perceive their physician as the most useful source (adjusted odds ratio [AOR], 0.46; 95% confidence interval (CI), 0.21-1.00), whereas patients with acute leukemia (vs other blood cancers) were more likely to perceive their physician as the most useful source (AOR, 2.49; 95% CI, 1.07-5.80). In terms of communicating treatment success rates, 70% preferred ≥1 method(s), and 88% preferred presentation in percentages. Our study suggests that decisional involvement and information preferences vary and should be assessed explicitly as part of each decision-making encounter.

A systematic review of factors associated with side-effect expectations from medical interventions

BACKGROUND

Fear of side-effects can result in non-adherence to medical interventions, such as medication and chemotherapy. Side-effect expectations have been identified as strong predictors of later perception of side-effects. However, research investigating predictors of side-effect expectations is disparate.

OBJECTIVE

To identify factors associated with side-effect expectations.

SEARCH STRATEGY

We systematically searched Embase, Ovid MEDLINE, Global Health, PsycARTICLES, PsycINFO, Web of Science and Scopus.

INCLUSION CRITERIA

Studies were included if they investigated associations between any predictive factor and expectations of side-effects from any medical intervention.

DATA EXTRACTION AND SYNTHESIS

We extracted information about participant characteristics, medication, rates of side-effects expected and predictors of side-effect expectations. Data were narratively synthesized.

MAIN RESULTS

We identified sixty-four citations, reporting on seventy-two studies. Predictors fell into five categories: personal characteristics, clinical characteristics, psychological traits and state, presentation format of information, and information sources used. Using verbal risk descriptors (eg 'common') compared to numerical descriptors (eg percentages), having lower quality of life or well-being, and currently experiencing symptoms were associated with increased side-effect expectations.

DISCUSSION AND CONCLUSIONS

Decreasing unrealistic side-effect expectations may lead to decreased experience of side-effects and increased adherence to medical interventions. Widespread communications about medical interventions should describe the incidence of side-effects numerically. Evidence suggests that clinicians should take particular care with patients with lower quality of life, who are currently experiencing symptoms and who have previously experienced symptoms from treatment. Further research should investigate different clinical populations and aim to quantify the impact of the media and social media on side-effect expectations.

The Utility of Systems Models of Stress and Coping for Applied Research

Contemporary conceptual models of stress and coping are intricate systems formulations that depict adaptation as a dynamic, interactional process. The inherent complexity of these models presents conceptual and methodological challenges that make testing a complete model difficult. This article makes the case for a more microanalytic strategy for applied coping research that, by centering attention and available resources on selected high-frequency, high-stress problems, permits more conceptually sophisticated and clinically informative analyses. In this context, the prevailing conceptual models have heuristic value for organizing the holistic study of adaptational processes. The utility of the proposed strategy for the development of problem-specific systems models is illustrated using the example of treatment-induced sterility from research on cancer adaptation.

Simple genetics language as source of miscommunication between genetics researchers and potential research participants in informed consent documents

Informed consent is based on communication, requiring language to convey meanings and ensure understandings. The purpose of this study was to investigate the use of language in informed consent documents used in the genetics research funded by Canadian Institutes of Health Research and Genome Canada. Consent documents were requested from the principal investigators in a recent round of funding. A qualitative content analysis was performed, supported by NVivo7™. Potential barriers to informed consent were identified, including language that was vague and variable, words with both technical and common meanings, novel phrases without clear meaning, a lack of definitions, and common concepts that assume new definitions in genetics research. However, we noted that difficulties in comprehension were often obscured because the words used were generally simple and familiar. We conclude that language gaps between researcher and potential research participants may unintentionally impair comprehension and ultimately impair informed consent in genomics research.

Informing and educating parents about the risks and outcomes of prematurity

The current process of educating and informing parents of the concerns and outcomes of premature infants is suboptimal, mostly because of modifiable factors. Proven methods to improve the transference of information are underused. In most institutions, the task to inform and educate parents is left to individual providers. Effective parent-clinician communication depends collectively on parents, clinicians, and the health care systems. Efforts must focus on improving communication and not on decreasing information provided to parents. If done successfully, we might find new and worthy allies in the trenches of the NICU.

Comprehension of the description of side effects in drug information leaflets: a survey of doctors, pharmacists and lawyers

BACKGROUND

The German Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM) states that it uses standardized terms to describe the probabilities of side effects in drug information leaflets. It is unclear, however, whether these terms are actually understood correctly by doctors, pharmacists, and lawyers.

METHODS

A total of 1000 doctors, pharmacists, and lawyers were questioned by mail, and 60.4% of the questionnaires were filled out and returned. In the absence of any particular, potentially suggestive context, the respondents were asked to give a numerical interpretation of each of 20 verbal expressions of probability. Side effects were the subject of a hypothetical physician-patient case scenario. The respondents were also asked to give percentages that they felt corresponded to the terms "common," "uncommon," and "rare." The values obtained were compared with the intended values of the BfArM.

RESULTS

The results obtained from the three professional groups resembled each other but stood in marked contrast to the BfArM definitions. With respect to side effects, the pharmacists matched the BfArM definitions most closely (5.8% "common," 1.9% "uncommon" and "rare"), followed by the physicians (3.5%, 0.3%, 0.9%) and the lawyers (0.7%, 0%, 0.7%). When the context of the side effects was not mentioned, the degree of agreement was much lower.

CONCLUSION

Statements about the frequency of side effects are found in all drug information leaflets. Only a small minority of the respondents correctly stated the meaning of terms that are used to describe the frequency of occurrence of side effects, even though they routinely have to convey probabilities of side effects in the course of their professional duties. It can be concluded that the BfArM definitions of these terms do not, in general, correspond to their meanings in ordinary language.

Cognitive and psychological reactions of the general population three months after the 2011 Tohoku earthquake and tsunami

Background

The largest earthquake on record in Japan (magnitude 9.0) occurred on March 11, 2011, and the subsequent tsunami devastated the Pacific coast of Northern Japan. These further triggered the Fukushima I nuclear power plant accidents. Such a hugely complex disaster inevitably has negative psychological effects on general populations as well as on the direct victims. While previous disaster studies enrolled descriptive approaches focusing on direct victims, the structure of the psychological adjustment process of people from the general population has remained uncertain. The current study attempted to establish a path model that sufficiently reflects the early psychological adaptation process of the general population to large-scale natural disasters.

Methods and Findings

Participants from the primary disaster area (n = 1083) and other areas (n = 2372) voluntarily participated in an online questionnaire study. By constructing path models using a structural equation model procedure (SEM), we examined the structural relationship among psychological constructs known related to disasters. As post-traumatic stress symptoms (PTS) were significantly more present in people in the primarily affected area than in those in secondary- or non-affected areas, the path models were constructed for the primary victims. The parsimoniously depicted model with the best fit was achieved for the psychological-adjustment centered model with quality of life (QoL) as a final outcome.

Conclusion

The paths to QoL via negative routes (from negative cognitive appraisal, PTS, and general stress) were dominant, suggesting the importance of clinical intervention for reducing negative cognitive appraisal, and for caring for general stress and PTS to maintain QoL at an early stage of psychological adaptation to a disaster. The model also depicted the presence of a positive route where positive cognitive appraisal facilitates post-traumatic growth (PTG) to achieve a higher QoL, suggesting the potential importance of positive psychological preventive care for unexpected natural disasters.

Uncertain Futures: Individual Risk and Social Context in Decision-Making in Cancer Screening

A core logic of cancer control and prevention, like much in public health, turns on the notion of decision-making under conditions of uncertainty. Population-level data are increasingly used to develop risk profiles, or estimates, that clinicians and the consumer public may use to guide individual decisions about cancer screening. Individual risk perception forms a piece of a larger social economy of decision-making and choice that makes population screening possible. Individual decision-making depends on accessing and interpreting available clinical information, filtered through the lens of personal values and both cognitive and affective behavioral processes. That process is also mediated by changing social roles and interpersonal relationships. This paper begins to elucidate the influence of this "social context" within the complexity of cancer screening. Reflecting on current work in risk and health, I consider how ethnographic narrative methods can enrich this model.

A review of human linguistic probability processing: General principles and empirical evidence

This article reviews research on how people use and understand linguistic expressions of uncertainty, with a view toward the needs of researchers and others interested in artificial intelligence systems. We discuss and present empirical results within an inductively developed theoretical framework consisting of two background assumptions and six principles describing the underlying cognitive processes.

How should risk be communicated to children: a cross-sectional study comparing different formats of probability information

BACKGROUND

Newborn screening, which identifies inherited disorders and sometimes carrier status, will increasingly involve health professionals in the provision of appropriate information and support to children and their families. The ability to understand carrier results relies on an understanding of probabilistic terms. However, little is known about how best to convey probabilistic medical information to children. Research with adult populations suggests information format significantly affects comprehension. This study aimed to explore which presentation format is most effective in conveying probabilistic information to children.

METHODS

A probabilistic task based on the cup game was used to measure which of five different formats was associated with greatest understanding in children aged 7-11 years old (n = 106). Formats used were verbal labels (e.g. rarely, sometimes), percentages, proportion-word (e.g. 1 in X), proportion-notation (e.g. 1:X) and pie charts. There was also an additional mixed format condition. In each trial a picture was presented of three cups, each with a different probability depicted beneath it, and the child was asked to select which cup was most likely to contain the ball. Three trials were presented per format. Children also rated how certain they were that they had answered correctly.

RESULTS

There was a significant relationship between format and comprehension scores. Post hoc tests showed children performed significantly better when probability was presented as a pie chart, in comparison to percentages, proportion-notation, proportion-word and mixed format trials. Furthermore, most children (84%) got all trials correct for this format and children were significantly more certain that their response was correct in the pie chart trials compared to all the other formats (p < 0.001). Significant positive correlations were found between self-ratings of certainty and comprehension of verbal labels, percentages and pie charts. Older age was also associated with better performance on all formats except percentages. Overall comprehension was calculated by summing the scores for the individual trials and this was independently associated with older age and higher IQ.

CONCLUSION

The results suggest that 7-11 year olds can understand probability information, but that the format used will significantly affect the accuracy and confidence with which children in this age group make judgements about the likelihood of an event. Of the formats studied, pie charts appear to be the optimal method of presenting probabilistic information to children in this age group. Health professionals and designers of health messages should be cognisant of this when communicating medical information to children aged 7-11 years old.

Design of the BRISC study: a multicentre controlled clinical trial to optimize the communication of breast cancer risks in genetic counselling

BACKGROUND

Understanding risks is considered to be crucial for informed decision-making. Inaccurate risk perception is a common finding in women with a family history of breast cancer attending genetic counseling. As yet, it is unclear how risks should best be communicated in clinical practice. This study protocol describes the design and methods of the BRISC (Breast cancer RISk Communication) study evaluating the effect of different formats of risk communication on the counsellee's risk perception, psychological well-being and decision-making regarding preventive options for breast cancer.

METHODS AND DESIGN

The BRISC study is designed as a pre-post-test controlled group intervention trial with repeated measurements using questionnaires. The intervention-an additional risk consultation-consists of one of 5 conditions that differ in the way counsellee's breast cancer risk is communicated: 1) lifetime risk in numerical format (natural frequencies, i.e. X out of 100), 2) lifetime risk in both numerical format and graphical format (population figures), 3) lifetime risk and age-related risk in numerical format, 4) lifetime risk and age-related risk in both numerical format and graphical format, and 5) lifetime risk in percentages. Condition 6 is the control condition in which no intervention is given (usual care). Participants are unaffected women with a family history of breast cancer attending one of three participating clinical genetic centres in the Netherlands.

DISCUSSION

The BRISC study allows for an evaluation of the effects of different formats of communicating breast cancer risks to counsellees. The results can be used to optimize risk communication in order to improve informed decision-making among women with a family history of breast cancer. They may also be useful for risk communication in other health-related services.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN14566836.

Chemotherapy as language: sound symbolism in cancer medication names

The concept of sound symbolism proposes that even the tiniest sounds comprising a word may suggest the qualities of the object which that word represents. Cancer-related medication names, which are likely to be charged with emotional meaning for patients, might be expected to contain such sound-symbolic associations. We analyzed the sounds in the names of 60 frequently-used cancer-related medications, focusing on the medications' trade names as well as the names (trade or generic) commonly used in the clinic. We assessed the frequency of common voiced consonants (/b/, /d/, /g/, /v/, /z/; thought to be associated with slowness and heaviness) and voiceless consonants (/p/, /t/, /k/, /f/, /s/; thought to be associated with fastness and lightness), and compared them to what would be expected in standard American English using a reference dataset. A Fisher's exact test for independence showed the chemotherapy consonantal frequencies to be significantly different from standard English (p=0.009 for trade; p<0.001 for "common usage"). For the trade names, the majority of the voiceless consonants were significantly increased compared to standard English; this effect was more pronounced with the "common usage" names (for the group, O/E=1.62; 95% CI [1.37, 1.89]). Hormonal and targeted therapy trade names showed the greatest frequency of voiceless consonants (for the group, O/E=1.76; 95% CI [1.20, 2.49]). Our results suggest that taken together, the names of chemotherapy medications contain an increased frequency of certain sounds associated with lightness, smallness and fastness. This finding raises important questions about the possible role of the names of medications in the experiences of cancer patients and providers.

A systematic review of information in decision aids

OBJECTIVE

We completed a systematic review of information reported as included in decision aids (DAs) for adult patients, to determine if it is complete, balanced and accurate.

SEARCH STRATEGY

DAs were identified using the Cochrane Database of DAs and searches of four electronic databases using the terms: 'decision aid'; shared decision making' and 'patients'; 'multimedia or leaflets or pamphlets or videos and patients and decision making'. Additionally, publications reporting DA development and actual DAs that were reported as publicly available on the Internet were consulted. Publications were included up to May 2006.

DATA EXTRACTION

Data were extracted on the following variables: external groups consulted in development of the DA, type of study used, categories of information, inclusion of probabilities, use of citation lists and inclusion of patient experiences.

MAIN RESULTS

68 treatment DAs and 30 screening DAs were identified. 17% of treatment DAs and 47% of screening DAs did not report any external consultation and, of those that did, DA producers tended to rely more heavily on medical experts than on patients' guidance. Content evaluations showed that (i) treatment DAs frequently omit describing the procedure(s) involved in treatment options and (ii) screening DAs frequently focus on false positives but not false negatives. About 1/2 treatment DAs reported probabilities with a greater emphasis on potential benefits than harms. Similarly, screening DAs were more likely to provide false-positive than false-negative rates.

CONCLUSIONS

The review led us to be concerned about completeness, balance and accuracy of information included in DAs.

Are There Test Administrator Effects in Large-Scale Educational Assessments?

Abstract. In large-scale educational assessments such as the Third International Mathematics and Sciences Study (TIMSS) or the Program for International Student Assessment (PISA), sizeable numbers of test administrators (TAs) are needed to conduct the assessment sessions in the participating schools. TA training sessions are run and administration manuals are compiled with the aim of ensuring standardized, comparable, assessment situations in all student groups. To date, however, there has been no empirical investigation of the effectiveness of these standardizing efforts. In the present article, we probe for systematic TA effects on mathematics achievement and sample attrition in a student achievement study. Multilevel analyses for cross-classified data using Markov Chain Monte Carlo (MCMC) procedures were performed to separate the variance that can be attributed to differences between schools from the variance associated with TAs. After controlling for school effects, only a very small, nonsignificant proportion of the variance in mathematics scores and response behavior was attributable to the TAs (< 1%). We discuss practical implications of these findings for the deployment of TAs in educational assessments.

ASSESSING SURGEONS' DISCLOSURE OF RISK INFORMATION BEFORE CAROTID ENDARTERECTOMY

BACKGROUND

To make an informed decision about treatment, patients need accurate information about the benefits and risks of treatment and 'non-treatment' options. A survey was conducted to determine patients' recall of the extent and effect of preoperative disclosure by surgeons to patients of risks about carotid endarterectomy (CEA).

METHODS

A self-administered questionnaire was given to 133 patients undergoing elective CEA in New South Wales. The primary outcome measures were patient recall of preoperative discussion, self-assessed estimates of stroke risk with and without surgery and receipt of written information before CEA.

RESULTS

A significantly higher proportion of patients recalled that their surgeon discussed the short-term stroke risk (i.e. within 30 days) if they decided to undergo CEA (86.2%) than if they decided not to have the procedure (76.9%) (P = 0.04). Of those patients who recalled the surgeon discussing their short-term stroke risk with CEA, only 24 (18.0%) were accurately able to quantify this risk. Patients were significantly more likely to recall their surgeon discussing their long-term stroke risk (i.e. within 2 years) if they decided not to have CEA (72.4%) than if they decided to have the CEA (31.5%) (P < 0.0001).

CONCLUSIONS

Patients recalled discussions with their surgeon about short-term stroke risk. Only a minority, however, accurately quantified their postoperative stroke risk. In view of variable patient recall, decision aids could assist.

Assessment of a Decision Aid to Assist Genetic Testing Research Participants in the Informed Consent Process

Limited attention has been given to applying decision-making theories from psychology to the content and process of informed consent in genetic testing research. Data are presented from a study that developed and assessed a psychological theory-based decision aid as part of the informed consent process. This innovative approach assisted at-risk women in assessing the consequences of participating in a research project that offered them free hemophilia A genetic carrier testing. Results suggest: (1) the decision aid can be incorporated into the consent process with few problems; (2) women of varying educational backgrounds can complete the decision aid; (3) while women consider many consequences of genetic testing, their primary focus is on the implications for their family; and (4) this is in marked contrast to the typical benefit-harm statements prepared by researchers for genetic testing.

You Say "Probable" and I Say "Likely": Improving Interpersonal Communication With Verbal Probability Phrases

When forecasters and decision makers describe uncertain events using verbal probability terms, there is a risk of miscommunication because people use different probability phrases and interpret them in different ways. In an effort to facilitate the communication process, the authors investigated various ways of converting the forecasters' verbal probabilities to the decision maker's terms. The authors present 3 studies in which participants judged the probabilities of distinct events using both numerical and verbal probabilities. They define several indexes of interindividual coassignment of phrases to the same events and evaluate the conversion methods by comparing the values of these indexes for the converted and the unconverted judgments. In all the cases studied, the conversion methods significantly reduced the error rates in communicating uncertainties.

The language of uncertainty in genetic risk communication: framing and verbal versus numerical information

Within a group of 300 medical students, two characteristics of risk communication in the context of a decision regarding prenatal diagnosis for cystic fibrosis are manipulated: verbal versus numerical probabilities and the negative versus positive framing of the problem (having a child with versus without cystic fibrosis). Independently of the manipulations, most students were in favor of prenatal diagnosis. The effect of framing was only significant in the conditions with verbal information: negative framing produced a stronger choice in favor of prenatal diagnosis than positive framing. The framing effect in the verbal conditions and its absence in the numerical conditions are explained by the dominance of the problem-occurrence orientation in health matters as well as a recoding process which is more likely to occur in the numerical (the probability "1-P" switches to its counterpart "P") than in the verbal conditions. The implications for the practice of genetic counseling are discussed.

The effectiveness of one-to-one risk communication interventions in health care: a systematic review

OBJECTIVES

To assess whether risk-communication interventions are associated with changes in patient knowledge, attitudes, and behaviors, and to identify aspects of these interventions that modify these effects.

DESIGN

Systematic review.

DATA SOURCES

96 studies from the period 1985-1996 retrieved by electronic searching of eight databases, hand searching of four journals, contacting key authors, and reference list searching.

MAIN OUTCOME MEASURES

The effect size of the principal outcome was identified from each study. Outcomes measuring behavioral change were preferred; if these were not available, knowledge, anxiety, or risk perceptions were used, according to the focus of the study. Data were available to calculate the principal effect sizes for 82 of the studies.

ANALYSIS

Meta-regression.

RESULTS

The methodologic qualities of the studies varied. Nevertheless, risk-communication interventions generally had positive (beneficial) effects. Interventions addressing treatment choices were associated with larger effects than were those in other contexts, such as prevention or screening. Interventions using individual risk estimates were associated with larger effects than were those using more general risk information. Two design variables were identified as effect modifiers: randomized controlled trials were associated with smaller effects than other designs, and dichotomous outcomes were associated with larger effects than continuous outcomes.

CONCLUSIONS

Risk communication interventions may be most productive if they include individual risk estimates in the discussion between professional and patient. Patient decisions about treatment appear more amenable to change by these interventions than attendance for screening or modification of risky behavior.

Impact of therapeutic research on informed consent and the ethics of clinical trials: a medical oncology perspective

PURPOSE

To create a more meaningful understanding of the informed consent process as it has come to be practiced and regulated in clinical trials, this discussion uses the experience gained from the conduct of therapeutic research that involves cancer patients.

DESIGN

After an introduction of the ethical tenets of the consent process in clinical research that involves potentially vulnerable patients as research subjects, background that details the use of written consent documents and of the term "informed consent" is provided. Studies from the cancer setting that examine the inadequacies of written consent documents, and the outcome of the consent process itself, are reviewed. Two ethically challenging areas of cancer clinical research, the phase I trial and the randomized controlled trial, are discussed briefly as a means of highlighting many dilemmas present in clinical trials. Before concluding, areas for future research are discussed.

RESULTS

Through an exclusive cancer research perspective, many current deficiencies in the informed consent process for therapeutic clinical trials can be critically examined. Also, new directions for improvements and areas of further research can be outlined and discussed objectively. The goals of such improvements and research should be prevention of further misguided or ineffective efforts to regulate the informed consent process.

CONCLUSION

To ignore this rich and interesting perspective potentially contributes to continued misunderstanding and apathy toward fulfilling the regulatory and ethically obligatory requirements involved in an essential communication process between a clinician-investigator and a potentially vulnerable patient who is considering clinical trial participation.

Recommendations for medical management of hereditary breast and ovarian cancer: the French National Ad Hoc Committee

BACKGROUND AND PURPOSE

Almost 10% of breast and ovarian cancers are familial, and the majority are linked to BRCA1 and BRCA2 germline mutations. Despite uncertainty about the management of female gene carriers, consensus guidelines have been established to assist practitioners and consultees in making health care decisions.

METHODOLOGY

The Ad Hoc Committee was composed of 14 experts appointed by the French National Institute for Health and Medical Research, all of whom attended eleven workshops at which more than 3500 articles were systematically analyzed. Five additional experts critically analysed the first version of the report. CRITERIA AND DECISION PROCESS: On a probability scale of the risk of developing breast or ovarian cancers, two thresholds were defined for use in determining whether an intervention would be worthwhile. The first is the threshold above which an intervention can be envisaged or recommended, and the second is the one below which an intervention can be ruled out; between the two, the decision has to be made on a case-by-case basis. SCREENING AND PREVENTIVE STRATEGIES ANALYZED: With respect to breast cancer: 1) hormonal interventions; 2) primary prevention (diet, family planning and chemoprevention); 3) screening (breast self-examination, clinician breast examination, tumor markers, imaging); 4) prophylactic mastectomy. With respect to ovarian cancer: 1) hormonal stimulation; 2) screening (clinical screening, ultrasound and tumor markers); 3) prophylactic oophorectomy.

MAIN CONCLUSIONS

For each strategy the following points were addressed: the information to be given to the consultee, the procedure and the indications. In addition, the committee's opinion about BRCA1 and BRCA2 mutation screening is that population-based, or even large-scale, implementation are not justified. Although no scientific evidence is available, the committee feels that specific management is indispensable and advocates the use of defined and evaluated procedures, and participation in clinical trials.

Using a treatment-tradeoff method to elicit preferences for the treatment of locally advanced non-small-cell lung cancer

The study was designed to evaluate a treatment-tradeoff method for its potential in helping lung cancer patients make treatment decisions. A treatment-tradeoff interview was conducted to determine how patients weighed potential survival benefits against the potential toxicities of different treatment options: 1) low-dose versus high-dose radiotherapy, and 2) high-dose radiotherapy versus combination chemo-radiotherapy. Fifty-six patients who had experienced cancer and 20 clinic staff participated; twenty of these participants repeated the interview in an assessment of response consistency. The treatment-tradeoff method proved feasible: all staff and 53 of the 56 patients were able to complete the process. A wide range of threshold scores across participants was observed for both tradeoffs. Sixty percent of the patients would accept the more toxic combination therapy over high-dose radiotherapy if the former offered a 10% absolute improvement in three-year survival. The method also proved reliable: test-retest correlations were high (tau ranged from 0.7 to 0.87 and r from 0.82 to 0.94) and test-retest mean score differences were low (1.3-4.2). The most clinically useful measure of consistency was a "preference consistency" index, which revealed that most patients declared the same treatment preference at test and retest. The authors conclude that, while there is great interindividual variability in willingness to accept aggressive treatments for lung cancer, patients' values can be consistently elicited with the tradeoff method. The method has potential for clinical application in decision making and for health-care policy development.

Shared understandings for informed consent: the relevance of psychological research on the provision of information

The achievement of informed consent from patients and potential research participants is considered a basic requirement in clinical care and clinical research, but ethicists have paid little attention to the psychological processes and social factors involved in sharing information between individuals. Although many studies on consent have provided useful results, they are rarely informed by basic research in the social sciences. As a result, there are a large number of methodological and conceptual issues which have not been adequately addressed. The purpose of this paper is to illustrate how the work of cognitive and social psychologists can provide insights that are both relevant and valuable to the process of attaining consent. Research in these areas within psychology has indicated that there are important individual differences in how much information people require and that patients' current state of mind can affect estimates of probability, thus making analogue studies misleading. Collaboration between psychologists and ethicists would be of great value in identifying likely areas of mutual interest, particularly the choice of language in consent forms and information sheets, the design of consent forms, the amount of information provided, and the specification of risks and benefits.

How age, outcome severity, and scale influence general medicine clinic patients' interpretations of verbal probability terms

OBJECTIVE

To assess whether the type of scale used (scaling effects) and the severity of outcome (outcome severity) influence patients' numerical interpretations of verbal probability expressions.

DESIGN

Cross-sectional survey of patients in a general medicine clinic.

SETTING

A university-based Department of Veterans Affairs Medical Center.

PARTICIPANTS

210 patients seen consecutively in a general medicine clinic.

MEASUREMENTS AND RESULTS

The patients were randomized to scale and health outcome (complications of surgery). Two scales (a long form and a short form) were used to expressly allow patients to choose probabilities less than 1%. The long form had a lower bound of "< 1 out of 1,000,000"; the short form had a lower bound of "< 1 out of 1,000." Two complications were used: "death from anesthesia" and "severe pneumonia." In the context of being told that their surgeon believed that the chance the complication would occur was "rare," patients were asked to give the numerical estimate of that chance. The values elicited on both scales were significantly different for the two outcomes, with the "rare" risk of death from anesthesia being characterized as less likely than the "rare" risk of severe pneumonia (F = 5.24, p = 0.023). Linear regression and three-factor analysis of variance showed significant differences in the probabilities elicited for scale, outcome, and age, with older patients generally responding with higher probabilities than did younger patients.

CONCLUSIONS

These findings suggest that the severity of the associated outcome and the scale used to elicit patients' numerical estimates of verbal probability expressions influence patients' quantitative interpretations of the verbal probability statement; and older patients respond with higher probabilities of negative outcomes than do younger patients. Future studies must continue to explore whether verbal probability expressions are adequate for communicating medical risk to patients or whether patients should be provided with numerical estimates of frequency.

The roles of experience and domain of expertise in using numerical and verbal probability terms in medical decisions

Verbal probability terms are frequently used in medical practice. In the present experiment the use of verbal and numerical probability terms in medical decisions was investigated. Interns, residents in surgery and internal medicine, surgeons, and internists were asked to make treatment decisions for three different cases (acute appendicitis, angina pectoris, and an imaginary disease) and were also asked to give numerical interpretations of a series of verbal probability terms. In the second stage of the experiment the respondents received the same cases, but with numerical probability terms. The results showed no effect of context or of domain experience on the interpretation of verbal terms. Residents and experienced surgeons more often agreed on treatment decisions when chance information was presented in numerical terms as compared with verbal terms. Physicians were less confident when verbal terms were presented, but only for the less familiar decision problems. Finally, physicians turned out to be better in Bayesian reasoning when numerical terms were used. Experienced physicians were quite accurate in estimating the posterior probability in the appendicitis case, but not in the imaginary-disease case.

The role of psychology in the teaching of medical ethics: the example of informed consent

Over the past two decades, psychology has become well established in the medical curriculum. This paper argues that it has much to say about ethical issues, particularly informed consent. Because psychology addresses such areas as providing information, ensuring understanding of this information, identifying situations in which coercion occurs and assessing competence, its inclusion in the curriculum is justified on ethical as well as scientific grounds. This has several implications, including the allocation of resources, collaboration with health and clinical psychologists and the timing of the teaching.

Patients' interpretations of verbal expressions of probability: implications for securing informed consent to medical interventions

Physicians often use verbal expressions of probability to characterize their uncertainty about outcomes and the risks or side effects of proposed therapies. However, there is an extensive literature that documents the inherent vagueness of such expressions. Because of the potential importance of probability terms to physician-patient communication and decision-making, we asked patients to tell us the odds they thought applicable to the term "rare," as used by their physician to discuss the likelihood of an adverse outcome from surgery. Patients were randomly assigned to one of three outcome groups: death, severe heart attack, or severe pneumonia. Demographic data were elicited from each subject, as were indicators of present health status, medical history for certain diseases and surgery, and life expectancy. Linear regression and ANOVA analyses of the responses indicate that patient age, education level, perceived health status, and recency of experience with disease and medical care influence patients' numeric interpretations. We discuss the implications of these results.