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IMPORTANCE: Prior research has shown differences in postoperative outcomes for patients treated by female and male surgeons. It is important to understand, from a health system and payer perspective, whether surgical health care costs differ according to the surgeon’s sex. OBJECTIVE: To examine the association between surgeon sex and health care costs among patients undergoing surgery. DESIGN, SETTING, AND PARTICIPANTS: This population-based, retrospective cohort study included adult patients undergoing 1 of 25 common elective or emergent surgical procedures between January 1, 2007, and December 31, 2019, in Ontario, Canada. Analysis was performed from October 2022 to March 2023. EXPOSURE: Surgeon sex. MAIN OUTCOME AND MEASURE: The primary outcome was total health care costs assessed 1 year following surgery. Secondarily, total health care costs at 30 and 90 days, as well as specific cost categories, were assessed. Generalized estimating equations were used with procedure-level clustering to compare costs between patients undergoing equivalent surgeries performed by female and male surgeons, with further adjustment for patient-, surgeon-, anesthesiologist-, hospital-, and procedure-level covariates. RESULTS: Among 1 165 711 included patients, 151 054 were treated by a female surgeon and 1 014 657 were treated by a male surgeon. Analyzed at the procedure-specific level and accounting for patient-, surgeon-, anesthesiologist-, and hospital-level covariates, 1-year total health care costs were higher for patients treated by male surgeons ($24 882; 95% CI, $20 780-$29 794) than female surgeons ($18 517; 95% CI, $16 080-$21 324) (adjusted absolute difference, $6365; 95% CI, $3491-9238; adjusted relative risk, 1.10; 95% CI, 1.05-1.14). Similar patterns were observed at 30 days (adjusted absolute difference, $3115; 95% CI, $1682-$4548) and 90 days (adjusted absolute difference, $4228; 95% CI, $2255-$6202). CONCLUSIONS AND RELEVANCE: This analysis found lower 30-day, 90-day, and 1-year health care costs for patients treated by female surgeons compared with those treated by male surgeons. These data further underscore the importance of creating inclusive policies and environments supportive of women surgeons to improve recruitment and retention of a more diverse and representative workforce.

IMPORTANCE: Sex- and gender-based differences in a surgeon’s medical practice and communication may be factors in patients’ perioperative outcomes. Patients treated by female surgeons have improved 30-day outcomes. However, whether these outcomes persist over longer follow-up has not been assessed. OBJECTIVE: To examine whether surgeon sex is associated with 90-day and 1-year outcomes among patients undergoing common surgeries. DESIGN, SETTING, AND PARTICIPANTS: A population-based retrospective cohort study was conducted in adults in Ontario, Canada, undergoing 1 of 25 common elective or emergent surgeries between January 1, 2007, and December 31, 2019. Analysis was performed between July 15 and October 20, 2022. EXPOSURE: Surgeon sex. MAIN OUTCOMES AND MEASURES: An adverse postoperative event, defined as the composite of death, readmission, or complication, was assessed at 90 days and 1 year following surgery. Secondarily, each of these outcomes was assessed individually. Outcomes were compared between patients treated by female and male surgeons using generalized estimating equations with clustering at the level of the surgical procedure, accounting for patient-, procedure-, surgeon-, anesthesiologist-, and facility-level covariates. RESULTS: Among 1 165 711 included patients, 151 054 were treated by a female and 1 014 657 by a male surgeon. Overall, 14.3% of the patients had 1 or more adverse postoperative outcomes at 90 days and 25.0% had 1 or more adverse postoperative outcomes 1 year following surgery. Among these, 2.0% of patients died within 90 days and 4.3% died within 1 year. Multivariable-adjusted rates of the composite end point were higher among patients treated by male than female surgeons at both 90 days (13.9% vs 12.5%; adjusted odds ratio [AOR], 1.08; 95% CI, 1.03-1.13) and 1 year (25.0% vs 20.7%; AOR, 1.06; 95% CI, 1.01-1.12). Similar patterns were observed for mortality at 90 days (0.8% vs 0.5%; AOR 1.25; 95% CI, 1.12-1.39) and 1 year (2.4% vs 1.6%; AOR, 1.24; 95% CI, 1.13-1.36). CONCLUSIONS AND RELEVANCE: After accounting for patient, procedure, surgeon, anesthesiologist, and hospital characteristics, the findings of this cohort study suggest that patients treated by female surgeons have lower rates of adverse postoperative outcomes including death at 90 days and 1 year after surgery compared with those treated by male surgeons. These findings further support differences in patient outcomes based on physician sex that warrant deeper study regarding underlying causes and potential solutions.

IMPORTANCE: People who survive hospitalization for COVID-19 are at risk for developing new cardiovascular, neurological, mental health, and inflammatory autoimmune conditions. It is unclear how posthospitalization risks for COVID-19 compare with those for other serious infectious illnesses. OBJECTIVE: To compare risks of incident cardiovascular, neurological, and mental health conditions and rheumatoid arthritis in 1 year following COVID-19 hospitalization against 3 comparator groups: prepandemic hospitalization for influenza and hospitalization for sepsis before and during the COVID-19 pandemic. DESIGN, SETTING, AND PARTICIPANTS: This population-based cohort study included all adults hospitalized for COVID-19 between April 1, 2020, and October 31, 2021, historical comparator groups of people hospitalized for influenza or sepsis, and a contemporary comparator group of people hospitalized for sepsis in Ontario, Canada. EXPOSURE: Hospitalization for COVID-19, influenza, or sepsis. MAIN OUTCOME AND MEASURES: New occurrence of 13 prespecified conditions, including cardiovascular, neurological, and mental health conditions and rheumatoid arthritis, within 1 year of hospitalization. RESULTS: Of 379 366 included adults (median [IQR] age, 75 [63-85] years; 54% female), there were 26 499 people who survived hospitalization for COVID-19, 299 989 historical controls (17 516 for influenza and 282 473 for sepsis), and 52 878 contemporary controls hospitalized for sepsis. Hospitalization for COVID-19 was associated with an increased 1-year risk of venous thromboembolic disease compared with influenza (adjusted hazard ratio, 1.77; 95% CI, 1.36-2.31) but with no increased risks of developing selected ischemic and nonischemic cerebrovascular and cardiovascular disorders, neurological disorders, rheumatoid arthritis, or mental health conditions compared with influenza or sepsis cohorts. CONCLUSIONS AND RELEVANCE: In this cohort study, apart from an elevated risk of venous thromboembolism within 1 year, the burden of postacute medical and mental health conditions among those who survived hospitalization for COVID-19 was comparable with other acute infectious illnesses. This suggests that many of the postacute consequences of COVID-19 may be related to the severity of infectious illness necessitating hospitalization rather than being direct consequences of infection with SARS-CoV-2.

Purpose: Caring for patients with low-acuity conditions in Emergency Departments (ED) is often thought to cost more than treating those patients in other ambulatory settings. Understanding the relative cost of care between settings has critical implications for healthcare policy and system design. Methods: We conducted a systematic review of papers comparing the cost of care for low-acuity and ambulatory care sensitive conditions in ED and other outpatient settings. We searched PubMed, EMBASE, CINAHL, and Web of Science for peer reviewed papers, plus Google for grey literature. We conducted duplicate screening and data extraction, and quality assessment of included studies using an adapted SIGN checklist for economic studies. We calculated an unweighted mean charge ratio across studies and summarized our findings in narrative and tabular format. Results: We identified one study comparing costs. 18 studies assessed physician or facility charges, conducted in the United States, United Kingdom, and Canada, including cohort analyses (5), charge analyses (5), survey (1), and database searches (5) assessing populations ranging from 370 participants to 60 million. Charge ratios ranged from 0.60 to 13.45 with an unweighted mean of 4.20. Most (12) studies were of acceptable quality. Conclusion: No studies since 2001 assess the comparative costs of ED versus non-ED care for low-acuity ambulatory conditions. Physician and facility charges for ED care are higher than in other ambulatory settings for low-acuity conditions. Empirical evidence is lacking to support that ED care is more costly than similar care in other ambulatory settings.

People with disabilities are at elevated risk of adverse short-term outcomes following hospitalization for acute infectious illness. No prior studies have compared long-term healthcare use among this high-risk population. We compared the healthcare use of adults with disabilities in the one year following hospitalization for COVID-19 vs. sepsis vs. influenza.

IMPORTANCE: Surgeon sex is associated with differential postoperative outcomes, though the mechanism remains unclear. Sex concordance of surgeons and patients may represent a potential mechanism, given prior associations with physician-patient relationships. OBJECTIVE: To examine the association between surgeon-patient sex discordance and postoperative outcomes. DESIGN, SETTING, AND PARTICIPANTS: In this population-based, retrospective cohort study, adult patients 18 years and older undergoing one of 21 common elective or emergent surgical procedures in Ontario, Canada, from 2007 to 2019 were analyzed. Data were analyzed from November 2020 to March 2021. EXPOSURES: Surgeon-patient sex concordance (male surgeon with male patient, female surgeon with female patient) or discordance (male surgeon with female patient, female surgeon with male patient), operationalized as a binary (discordant vs concordant) and 4-level categorical variable. MAIN OUTCOMES AND MEASURES: Adverse postoperative outcome, defined as death, readmission, or complication within 30-day following surgery. Secondary outcomes assessed each of these metrics individually. Generalized estimating equations with clustering at the level of the surgical procedure were used to account for differences between procedures, and subgroup analyses were performed according to procedure, patient, surgeon, and hospital characteristics. RESULTS: Among 1 320 108 patients treated by 2937 surgeons, 602 560 patients were sex concordant with their surgeon (male surgeon with male patient, 509 634; female surgeon with female patient, 92 926) while 717 548 were sex discordant (male surgeon with female patient, 667 279; female surgeon with male patient, 50 269). A total of 189 390 patients (14.9%) experienced 1 or more adverse postoperative outcomes. Sex discordance between surgeon and patient was associated with a significant increased likelihood of composite adverse postoperative outcomes (adjusted odds ratio [aOR], 1.07; 95% CI, 1.04-1.09), as well as death (aOR, 1.07; 95% CI, 1.02-1.13), and complications (aOR, 1.09; 95% CI, 1.07-1.11) but not readmission (aOR, 1.02; 95% CI, 0.98-1.07). While associations were consistent across most subgroups, patient sex significantly modified this association, with worse outcomes for female patients treated by male surgeons (compared with female patients treated by female surgeons: aOR, 1.15; 95% CI, 1.10-1.20) but not male patients treated by female surgeons (compared with male patients treated by male surgeons: aOR, 0.99; 95% CI, 0.95-1.03) (P for interaction = .004). CONCLUSIONS AND RELEVANCE: In this study, sex discordance between surgeons and patients negatively affected outcomes following common procedures. Subgroup analyses demonstrate that this is driven by worse outcomes among female patients treated by male surgeons. Further work should seek to understand the underlying mechanism.

Background: Up to 20% of medical students are unable to reach competency in laparoscopic surgery. It is unknown whether these difficulties arise from heterogeneity in neurological functioning across individuals. We sought to examine the differences in neurological functioning during laparoscopic tasks between high- and low-performing medical students using functional magnetic resonance imaging (fMRI). Methods: This prospective cohort study enrolled North American medical students who were within the top 20% and bottom 20% of laparoscopic performers from a previous study. Brain activation was recorded using fMRI while participants performed peg-pointing, intracorporeal knot tying (IKT), and the Pictorial Surface Orientation (PicSOr) test. Brain activation maps were created and areas of activation were compared between groups. Results: In total, 9/12 high and 9/13 low performers completed the study. High performers completed IKT faster and made more successful knot ties than low performers [standing: 23.5 (5.0) sec vs. 37.6 (18.4) sec, p = 0.03; supine: 23.2 (2.5) sec vs. 72.7 (62.8) sec, p = 0.02; number of successful ties supine, 3 ties vs. 1 tie, p = 0.01]. Low performers showed more brain activation than high performers in the peg-pointing task (q< 0.01), with no activation differences in the IKT task. There were no behavioral differences in the PiCSOr task. Conclusions: This study is the first to show differences between low and high performers of laparoscopic tasks at the brain level. This pilot study has shown the feasibility of using fMRI to examine laparoscopic surgical skills. Future studies are needed for further exploration of our initial findings.

IMPORTANCE: Sex-based income disparities are well documented in medicine and most pronounced in surgery. These disparities are commonly attributed to differences in hours worked. One proposed solution to close the earnings gap is a fee-for-service payment system, which is theoretically free of bias. However, it is unclear whether a sex-based earnings gap persists in a fee-for-service system when earnings are measured on the basis of hours worked. OBJECTIVE: To determine whether male and female surgeons have similar earnings for each hour spent operating in a fee-for-service system. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional, population-based study used administrative databases from a fee-for-service, single-payer health system in Ontario, Canada. Surgeons who submitted claims for surgical procedures performed between January 1, 2014, and December 31, 2016, were included. Data analysis took place from February 2018 to December 2018. EXPOSURES: Surgeon sex. MAIN OUTCOMES AND MEASURES: This study compared earnings per hour spent operating between male and female surgeons and earnings stratified by surgical specialty in a matched analysis. We explored factors potentially associated with earnings disparities, including differences in procedure duration and type between male and female surgeons and hourly earnings for procedures performed primarily on male vs female patients. RESULTS: We identified 1 508 471 surgical procedures claimed by 3275 surgeons. Female surgeons had practiced fewer years than male surgeons (median [interquartile range], 8.4 [2.9-16.6] vs 14.7 [5.9-25.7] years; P < .001), and the largest proportion of female surgeons practiced gynecology (400 of 819 female surgeons [48.8%]). Hourly earnings for female surgeons were 24% lower than for male surgeons (relative rate, 0.76 [95% CI, 0.74-0.79]; P < .001). This disparity persisted after adjusting for specialty and in matched analysis stratified by specialty, with the largest mean differences in cardiothoracic surgery (in US dollars: $59.64/hour) and orthopedic surgery ($55.45/hour). There were no differences in time taken by male and female surgeons to perform common procedures; however, female surgeons more commonly performed procedures with the lowest hourly earnings. CONCLUSIONS AND RELEVANCE: Even within a fee-for-service system, male and female surgeons do not have equal earnings for equal hours spent working, suggesting that the opportunity to perform the most lucrative surgical procedures is greater for men than women. These findings call for a comprehensive analysis of drivers of sex-based earning disparities, including referral patterns, and highlight the need for systems-level solutions.

BACKGROUND:The risk of death in people after their first admission to hospital or first presentation to the emergency department for any reason is not known. The objective of this study was to estimate the risk of death among older adults who had had no admissions to hospital or emergency department visits in the preceding 5 years.METHODS:We used administrative data from Ontario, Canada, from 2007 to 2017 to measure the 5-year risk of death in community-dwelling adults aged 66 years and older after their first planned or unplanned hospital admission or emergency department visit, and among those who were neither admitted to hospital nor presented to the emergency department. We describe how this risk varied by age.RESULTS:Among 922 074 community-dwelling older adults, 12.7% died (116 940 deaths) over a follow-up of 3 112 528 person-years (standardized mortality rate 53.8 per 1000 person-years). After the first unplanned hospital admission, 39.7% died (59 234 deaths, standardized mortality rate 127.6 per 1000 person-years). After the first planned hospital admission, 13.0% died (10 775 deaths, standardized mortality rate 44.6 per 1000 person-years). After the first visit to the emergency department, 10.9% died (35 663 deaths, standardized mortality rate 36.2 per 1000 person-years). Among those with neither an emergency department visit nor hospital admission during follow-up, 3.1% died (11 268 deaths, standardized mortality rate 29.6 per 1000 person-years). Slightly more than half of all deaths were in those with first unplanned hospital admission (50.7%).INTERPRETATION:Death within 5 years of first unplanned hospital admission for older adults is frequent and common. Knowledge of this risk may influence counselling and patient preferences and may be useful in research and analyses for health system planning.

IMPORTANCE: Trauma of hospitalization refers to the depersonalizing and stressful experience of a hospital admission and is hypothesized to increase the risk of readmission after discharge. OBJECTIVES: To characterize the trauma of hospitalization by measuring patient-reported disturbances in sleep, mobility, nutrition, and mood among medical inpatients, and to examine the association between these disturbances and the risk of unplanned return to hospital after discharge. DESIGN, SETTING, AND PARTICIPANTS: This prospective cohort study enrolled participants between September 1, 2016, and September 1, 2017, at 2 academic hospitals in Toronto, Canada. Participants were adults admitted to the internal medicine ward for more than 48 hours. Participants were interviewed before discharge using a standardized questionnaire to assess sleep, mobility, nutrition, and mood. Responses for each domain were dichotomized as disturbance or no disturbance. Disturbance in 3 or 4 domains (the upper tertile) was considered high trauma of hospitalization, and disturbance in 0 to 2 domains (the lower 2 tertiles) was considered low trauma. MAIN OUTCOME AND MEASURES: The primary outcome was readmission or emergency department visit within 30 days of discharge. The association between trauma of hospitalization and the primary outcome was examined using logistic regression, adjusted for age; sex; length of stay; Charlson Comorbidity Index Score; Laboratory-Based Acute Physiology Score; and baseline disturbances in sleep, mobility, nutrition, and mood. RESULTS: A total of 207 patients participated, of whom 82 (39.6%) were women and 125 (60.4%) were men, with a mean (SD) age of 60.3 (16.8) years. Among the 207 participants, 75 (36.2%) reported sleep disturbance, 162 (78.3%) reported mobility disturbance, 114 (55.1%) reported nutrition disturbance, and 48 (23.2%) reported mood disturbance. Nearly all participants (192 [92.8%]) described a disturbance in at least 1 domain, and 61 participants (29.5%) had high trauma exposure. A statistically significant 15.8% greater absolute risk of readmission or emergency department visit was found in participants with high trauma (37.7%; 95% CI, 25.9%-51.1%) compared with those with low trauma (21.9%; 95% CI, 15.7%-29.7%), which remained statistically significant after adjusting for baseline characteristics (adjusted odds ratio, 2.52; 95% CI, 1.24-5.17; P = .01) and propensity score matching (odds ratio, 2.47; 95% CI, 1.11-5.73; P = .03). CONCLUSIONS AND RELEVANCE: Disturbances in sleep, mobility, nutrition, and mood were common in medical inpatients; such trauma of hospitalization may be associated with a greater risk of 30-day readmission or emergency department visit after hospital discharge.

With single-payer public health insurance again on the political radar in the United States at both the state (California) and federal (Democrat party) levels, the performance of the Canadian health care system during the last 50 years and the lessons it may offer should be considered. Canadians are proud of their universal approach to health insurance based on need rather than income. The system has many strengths, such as the ease of obtaining care, relatively low costs, and low administrative costs, with effectiveness and safety roughly on par with other countries, including those, such as the United States, that spend considerably more per capita. There are increasing frustrations, however, with system performance, especially with issues related to access and coordination of care. Medicine has changed dramatically since the introduction of Canadian Medicare in the late 1960s, which primarily covered acute care physician and hospital services—the needs of the time. Meaningful reforms that match coverage and services to changing needs, especially those of community-based patients with multiple chronic conditions, have been difficult to implement. The status quo represents a compromise struck decades ago between payers and physicians and organizations that provide health care, and the current system works just well enough for those who both need it and vote. Enacting substantial change simply carries too much risk. Perhaps the most important lesson that the United States can learn from Canada’s experience during the last 50 years is that a single-payer health care system solves a lot of problems, but it does not equate to an integrated, well-managed system that can readily meet the changing health care needs of a population.

Hospitals are increasingly shifting toward value-based reimbursement and focusing on cost consciousness and patient experience. These concepts are crucial to high-quality, affordable healthcare. However, physicians are not well-trained in factoring cost and patient experience into clinical decisions. The addition of these ideas may create the opportunity for patient harm by depriving patients of necessary care. We discuss ways for physicians to mitigate this risk by engaging in online high value care curricula, using a “5-Question High Value Care Time Out,” getting mentorship from master clinicians and using clinical decision support tools.

ObjectiveTo determine whether patient-surgeon gender concordance is associated with mortality of patients after surgery in the United States.DesignRetrospective observational study.SettingAcute care hospitals in the US.Participants100% of Medicare fee-for-service beneficiaries aged 65-99 years who had one of 14 major elective or non-elective (emergent or urgent) surgeries in 2016-19.Main outcome measuresMortality after surgery, defined as death within 30 days of the operation. Adjustments were made for patient and surgeon characteristics and hospital fixed effects (effectively comparing patients within the same hospital).ResultsAmong 2 902 756 patients who had surgery, 1 287 845 (44.4%) had operations done by surgeons of the same gender (1 201 712 (41.4%) male patient and male surgeon, 86 133 (3.0%) female patient and female surgeon) and 1 614 911 (55.6%) were by surgeons of different gender (52 944 (1.8%) male patient and female surgeon, 1 561 967 (53.8%) female patient and male surgeon). Adjusted 30 day mortality after surgery was 2.0% for male patient-male surgeon dyads, 1.7% for male patient-female surgeon dyads, 1.5% for female patient-male surgeon dyads, and 1.3% for female patient-female surgeon dyads. Patient-surgeon gender concordance was associated with a slightly lower mortality for female patients (adjusted risk difference −0.2 percentage point (95% confidence interval −0.3 to −0.1); P<0.001), but a higher mortality for male patients (0.3 (0.2 to 0.5); P<0.001) for elective procedures, although the difference was small and not clinically meaningful. No evidence suggests that operative mortality differed by patient-surgeon gender concordance for non-elective procedures.ConclusionsPost-operative mortality rates were similar (ie, the difference was small and not clinically meaningful) among the four types of patient-surgeon gender dyads.

Background:Physicians diagnose and treat suspected hypogonadism in older men by extrapolating from the defined clinical entity of hypogonadism found in younger men. We conducted a systematic review to estimate the accuracy of clinical symptoms and signs for predicting low testosterone among aging men.Methods:We searched the MEDLINE and Embase databases (January 1966 to July 2014) for studies that compared clinical features with a measurement of serum testosterone in men. Three of the authors independently reviewed articles for inclusion, assessed quality and extracted data.Results:Among 6053 articles identified, 40 met the inclusion criteria. The prevalence of low testosterone ranged between 2% and 77%. Threshold testosterone levels used for reference standards also varied substantially. The summary likelihood ratio associated with decreased libido was 1.6 (95% confidence interval [CI] 1.3–1.9), and the likelihood ratio for absence of this finding was 0.72 (95% CI 0.58–0.85). The likelihood ratio associated with the presence of erectile dysfunction was 1.5 (95% CI 1.3–1.8) and with absence of erectile dysfunction was 0.83 (95% CI 0.76–0.91). Of the multiple-item instruments, the ANDROTEST showed both the most favourable positive likelihood ratio (range 1.9–2.2) and the most favourable negative likelihood ratio (range 0.37–0.49).Interpretation:We found weak correlation between signs, symptoms and testosterone levels, uncertainty about what threshold testosterone levels should be considered low for aging men and wide variation in estimated prevalence of the condition. It is therefore difficult to extrapolate the method of diagnosing pathologic hypogonadism in younger men to clinical decisions regarding age-related testosterone decline in aging men.

AbstractBackgroundMaking an accurate diagnosis is a core skill residents must develop. Assessments of this skill and decisions to grant residents clinical independence often are based on global impressions. A workplace-based assessment of diagnostic accuracy could be a useful part of a competency-based assessment program and could inform decisions about granting residents independence.InnovationWe developed a method for measuring diagnostic accuracy that was integrated into the workflow of internal medicine residents and attending physicians.MethodsFour senior medical residents and 6 attending physicians working in the internal medicine clinical teaching unit of a tertiary hospital participated in this study. To determine their diagnostic accuracy, residents documented a leading diagnosis for each patient they evaluated in the emergency department. After reviewing each case with the resident and after examining the patient, the resident's attending physician documented the diagnosis. Discharge diagnosis was determined by retrospective chart review to allow determination of resident and attending physician diagnostic accuracy. Data were collected for 240 consecutive patients referred for a medicine consultation.ResultsResident diagnostic accuracy was 66 (95 CI 60–72), whereas attending physician accuracy was significantly higher at 79 (95 CI 74–84, P < .001). By logistic regression, the accuracy of the attending physician was found to be influenced by the accuracy of the resident. Participants felt this process motivated them to improve their clinical reasoning.ConclusionsMeasuring resident diagnostic accuracy provides information that could be used in a competency-based assessment program to provide feedback and motivation to stimulate performance improvement.

AbstractObjective:To determine influenza vaccination rates, vaccine effectiveness, and factors influencing vaccination decisions among house staff.Design:Cross-sectional survey.Setting and Participants:All residents registered at the University of Toronto were surveyed after the 1999-2000 influenza season. Of the 1,159 questionnaires mailed, 670 (58%) could be evaluated.Results:Influenza-like illnesses were reported by 36% of house staff. The vaccination rate was 51% among respondents, being highest for community and occupational medicine and pediatric staff (77% and 75%) and lowest for psychiatry, surgery, and radiology staff (32%, 36%, and 36%). Vaccinees reported significantly fewer episodes of illness (42 vs 54 per 100 subjects; P= .03) and fewer days of illness (272 vs 374 per 100 subjects; P= .02); absenteeism was not different (63 vs 69 per 100 subjects; P= .69). Self-protection was the most common reason for vaccination. Vaccinees believed the vaccine was more effective than did non-vaccinees (P< .01). Non-vaccinees considered influenza-like symptoms the most important side effect of the vaccine. Busy schedules and inconvenience were the most common reasons for not getting vaccinated. Overall, 44% of house staff believed the influenza vaccine should be mandatory.Conclusions:Influenza-like illness was common among house staff. They tended to work through their illnesses, potentially putting patients at risk. They were motivated mostly by self-protection and did report a benefit. Despite busy schedules and an unfounded fear of getting influenza symptoms from the vaccine, many thought the vaccine should be mandatory.

The objective of this study was to determine whether patients with Crohn's disease (CD) value the absolute reduction in postoperative recurrence risk attributable to therapy with mesalamine (5-ASA). One hundred subjects evaluated state A (taking 5-ASA; 25% risk of recurrence), state B (not taking 5-ASA; 40% risk of recurrence), and state C (100% risk of recurrence) by rank order, visual analog scale (VAS), and standard gamble (SG). Sixty-five of 91 patients (71 %) with completed and usable questionnaires had the same preference order for state A (25% risk), state B (40% risk), and state C (100% risk) on both the VAS and the SG. The mean scores for state A (25% risk), state B (40% risk), and state C (100% risk), respectively, were 67.5, 49.8, and 19.8 on the VAS and 0.977, 0.972, and 0.910 on the SG. Subgroup analyses using stepwise logistic regression showed that risk attitude seemed to be predictive of subjects' preferences for 5-ASA. These results suggest that most subjects seem to value the 15% absolute risk reduction offered by 5-ASA. Furthermore, the SG seems to be a feasible method for measuring utilities for uncertain health states in patients with CD. Key words:standard gamble; risk attitude; treatment interventions; uncertain health states. (Med Decis Making 2000;20:72-78)

BACKGROUND AND METHODS: We performed a randomized trial of the incremental impact of high-volume contrast computed tomographic scan of the brain plus trimodal evoked potentials vs magnetic resonance imaging of the brain on neurologists' diagnostic labeling of patients with suspected multiple sclerosis (MS). Two hundred and four patients with suspected MS (clinically possible 59% or probable 41%McAlpine criteria) were assessed by two neurologists. Patients were diagnostically categorized after reviewing the results of the tests presented in random order. RESULTS: Most of the change in diagnostic categorization occurred after presenting the first test result irrespective of result sequence (X2=0.01, P=.99). The diagnoses became more definitive when all test results were available (P&lt;.001). Magnetic resonance imaging and evoked potential were suggestive of MS equally frequently (X2=0.57, P=.45). CONCLUSION: In suspected MS, there is no difference in diagnostic effect between brain magnetic resonance image scanning and computed tomography plus trimodal evoked potentials.

BACKGROUND AND METHODS: We examined the effect on health perceptions of a diagnostic workup in 172 patients with suspected multiple sclerosis (MS) using two questionnnaires (Mishel, Rand Medical Outcome Study) and three visual analogue scales measuring distress. Patients were categorized into "MS," "not MS," or "still uncertain" groups. RESULTS: Patients with a definitive diagnosis reported a significant decrease in uncertainty (analysis of variance [ANOVA] P=.0004). The Medical Outcome Study showed aslightlyworsened perceived current health status (ANOVA P=.02) and future health outlook (ANOVAP=.001) in the MS group compared with the other two groups. Distress over physical symptoms decreased in all three groups and anxiety was more likely to decrease than increase even in those with MS. Prognostic uncertainty distress decreased in the not MS group and still uncertain groups, whereas it remained unchanged in the MS group (P=.9156). CONCLUSION: Significant and generally beneficial changes in patient health perceptions are seen associated with a neurologic workup in suspected MS, irrespective of the final diagnosis.

A decision analysis was conducted to examine whether health care workers should receive short-term (42 days) zidovudine treatment following percutaneous exposure to blood, as well as to determine the value of testing "donor" (patient's) blood. Three alternative options were analyzed: treat all, treat none, and test. In the treat all option, all health care workers receive short-term zidovudine therapy immediately after exposure; in the treat none option, no one receives zidovudine; and in the test option, donor blood is tested, and if it is human immunodeficiency virus (HIV) positive, zidovudine is given. Baseline variables were obtained from the literature. Each outcome was expressed as a utility; this is a method of quantifying the values that persons place on different health states. The results showed that the test option was preferred. Sensitivity analyses indicated that even if the risk of seroconversion were zero or the effectiveness of zidovudine were zero or the drug were withheld, this option was preferred, thus indicating some value of testing other than merely identifying health care workers who should receive zidovudine. In the baseline analysis, this was derived from the fact that approximately 95% of the health care workers would be reassured by a negative test; ie, only approximately 5% of donors are HIV positive. If the prevalence of HIV seropositivity exceeded 42%, the treat none option was preferred. This was found to be due to the fact that increased numbers of health care workers would be told that they were exposed to HIV-positive blood. The "worrying factor" associated with such an exposure was such that above 42% HIV seropositivity, the treat none option was preferred overall. Thus, the real value of testing donor blood is in identifying those persons (>95%) who could be told that they were exposed to HIV-negative blood, that is, reducing their worrying factor to zero. Because acquired immunodeficiency syndrome is a fatal disease, and given that zidovudine is the only available therapeutic option at present, the drug has an important role to play if its effectiveness is greater than zero.(Arch Intern Med. 1991;151:2033-2040)

OBJECTIVE:: To determine the value of conjunctival pallor in ruling in or ruling out the presence of severe anemia (hemoglobin 90 g/L) and to determine the interobserver agreement in assessing this sign. DESIGN:: Patients were prospectively assessed for pallor by at least one of three observers. All observations were made without information of the patient's hemoglobin value or of another observer's assessment. SETTING:: Tertiary-care, university-affiliated teaching hospital. PATIENTS:: Three hundred and two medical and surgical inpatients. MEASUREMENTS AND MAIN RESULTS:: Likelihood ratios (LRs) calculated for conjunctival pallor present, borderline, and absent were as follows: pallor present, LR 4.49 (95% confidence interval [CI] 1.80, 10.99); pallor borderline, LR 1.80 (95% CI 1.18, 2.62); pallor absent, LR 0.61 (95% CI 0.44, 0.80). Kappa scores of interobserver agreement between paired observers were 0.75 and 0.54. CONCLUSIONS:: The presence of conjunctival pallor, without other information suggesting anemia, is reason enough to perform a hemoglobin determination. The absence of conjunctival pallor is not likely to be of use in ruling out severe anemia. With well-defined criteria, interobserver agreement is good to very good.

In the absence of good clinical evidence from a randomized trial, the authors performed a decision analysis to determine the potential value of early elective surgery (OPNOW) for patients with left-sided Staphylococcus aureusinfective endocarditis. Initial impressions (before per formance of decision analysis) and initial runs at the formal models using probability estimates derived from clinicians suggested that OPNOW (i.e., within a few days of starting antibiotics) offered no advantage over attempted medical cure (WAIT) (life expectancy: WAIT = 325 weeks; OPNOW = 255 weeks). Extensive sensitivity analyses identified critical variables that needed further empirical estimation. The Manitoba Health Services Commission database identified 127 incident cases of endocarditis between April 1, 1979, and March 31, 1985, enabling estimation of values for these critical variables. With these estimates, the early surgery strategy appeared much better than the previous analyses had suggested (life expectancy: WAIT = 208 weeks, OPNOW = 256 weeks). The authors believe that this approach of com bining decision analysis with medical claims databases is useful as an alternative or precursor to randomized trials, especially where the resource requirements and logistic difficulties of performing randomized trials are great. Key words:infective endocarditis; valve replacement; therapy; databases. (Med Decis Making 8:165-174, 1988)

Between October 30 and November 5, 1980, the Professional Association of Interns and Residents of Ontario called a strike of house staff in Ontario's teaching hospitals. The authors obtained data concerning utilization of laboratory tests and radiology procedures during that period and for the same days 2 weeks before and after the strike. During the strike period, the number of tests performed per patient day decreased by only 8.3. After accounting for proportional changes in emergency and nonemergency admissions, there was no significant change in the number of tests or relative value units performed per patient day as a result of the strike. These results suggest that the volume of tests performed in teaching hospitals is more likely related to the case mix and severity of illness of patients admitted to these institutions than to a pure “teaching effect.”

Meta-analytic methods were applied to review clinical trials published in English that have assessed the efficacy of parenteral nutrition for cirrhotic patients with acute hepatic encephalopathy. Modified amino acid solutions containing increased amounts of branched-chain amino acids were used as part of the treatment regimen in all studies. Pooled analysis of five randomized controlled studies showed a highly significant improvement in mental recovery (p < 0.001) from high-grade encephalopathy over follow-up times varying from 5 to 14 days. The significance level of the treatment effect did not change when the analysis was repeated using alternative methods of counting and attributing events in these trials. Sharp differences in direction of treatment effect precluded pooling case fatality data. Two studies reported an increased risk of death in the treatment group. Two others showed a clear benefit from administration of parenteral nutrition: the aggregate relative risk reduction was 0.59 (95% confidence interval: 0.230.80, p = 0.002). Addition of unpublished data from a third positive study increased the relative risk reduction to 0.82 (p < 0.0001), and the most conservative interpretation of the published data still yielded a significant reduction in mortality (p = 0.023). However, given the uncertainty about effects on mortality and short follow-up times in all studies, a confirmatory randomized controlled trial with longer follow-up periods is warranted.

OBJECTIVE:??To determine the value of conjunctival pallor in ruling in or ruling out the presence of severe anemia (hemoglobin 90 g/L) and to determine the interobserver agreement in assessing this sign.DESIGN:??Patients were prospectively assessed for pallor by at least one of three observers. All observations were made without information of the patient's hemoglobin value or of another observer's assessment.SETTING:??Tertiary-care, university-affiliated teaching hospital.PATIENTS:??Three hundred and two medical and surgical inpatients.MEASUREMENTS AND MAIN RESULTS:??Likelihood ratios (LRs) calculated for conjunctival pallor present, borderline, and absent were as follows: pallor present, LR 4.49 (95% confidence interval [CI] 1.80, 10.99); pallor borderline, LR 1.80 (95% CI 1.18, 2.62); pallor absent, LR 0.61 (95% CI 0.44, 0.80). Kappa scores of interobserver agreement between paired observers were 0.75 and 0.54.CONCLUSIONS:??The presence of conjunctival pallor, without other information suggesting anemia, is reason enough to perform a hemoglobin determination. The absence of conjunctival pallor is not likely to be of use in ruling out severe anemia. With well-defined criteria, interobserver agreement is good to very good.

This paper describes how to estimate probabilities and outcome values for decision trees. Probabilities are usually derived from published studies, but occasionally are derived from existing databases, primary data collection, or expert judgment. Outcome values represent quantitative estimates of the desirability of the outcome states, and are often expressed as utility values between 0 and 1. Utility values for different health states can be derived from the published literature, from direct measurement in appropriate subjects, or from expert opinion. Methods for assigning utilities to complex outcome states are described, and the concept of quality-adjusted life years is introduced. Key words:decision analysis; expected value; utility; sensitivity analysis; decision trees; probability. (Med Decis Making 1997;17:136-141)

This part of a five-part series covering practical issues in the performance of decision analysis outlines the basic strategies for building decision trees. The authors offer six recommendations for building and programming decision trees. Following these six recommendations will facilitate performance of the sensitivity analyses required to achieve two goals. The first is to find modeling or programming errors, a process known as "debugging" the tree. The second is to determine the robustness of the qualitative conclusions drawn from the analysis. Key words: decision analysis; expected value; utility; sensitivity analysis; decision trees; probability. (Med Decis Making 1997;17: 126-135)

Clinical decisions often have long-term implications. Analysts encounter difficulties when employing conventional decision-analytic methods to model these scenarios. This occurs because probability and utility variables often change with time and conventional decision trees do not easily capture this dynamic quality. A Markov analysis performed with current computer software programs provides a flexible and convenient means of modeling long-term scenarios. However, novices should be aware of several potential pitfalls when attempting to use these programs. When deciding how to model a given clinical problem, the analyst must weigh the simplicity and clarity of a conventional tree against the fidelity of a Markov analysis. In direct comparisons, both approaches gave the same qualitative answers. Key words:decision analysis; expected value; utility; sensitivity analysis; decision trees; probability. (Med Decis Making 1997; 17:152-159)

This paper is the fourth of a five-part series that describes the principles of construction and evaluation of valid decision models. In this review, the authors describe the key principles of detecting and eliminating structural and programming errors in decision trees (debugging). In addition, they offer guidelines to facilitate the interpretation of analytic results of decision models. Key words:decision analysis; expected value; utility ; sensitivity analysis; decision trees; probability. (Med Decis Making 1997;17:142- 151)

A decision tree model was used to estimate the incremental cost per quality-adjusted life year (QALY) of low- as opposed to high-osmolality contrast media for cardiac angiography. Analyses were done from the viewpoints of a third-party payer and society using data from a randomized trial and the literature. Assuming low-osmolality media reduce the risk of myocardial infarction and stroke, the incremental cost per QALY gained with these media is $17,264 in high-risk or $47,874 in low-risk patients for a third-party payer. From a societal viewpoint, the corresponding costs are $649 and $35,509. These estimates are sensitive to the cost and volume of the contrast medium employed and to the estimate of reduction in severe adverse events with low-osmolality media. The authors conclude that, in the context of restricted budgets, limiting the use of low-osmolality media to high-risk patients is justifiable, as the incremental cost per QALY in high-risk patients may be reasonable and it is not certain that low-osmolality media prevent severe or fatal events. A considerable reduction in the cost per QALY gained is possible by minimizing the volume of contrast medium used. Key words: contrast media; low-osmolality; high-osmolality; cardiac angiography; cost-utility; cost-benefit; cost-effectiveness; economic analysis. (Med Decis Making 1994;14:325- 335)

The objective of the study was to determine the preferred treatment strategy for elderly patients with chronic nonvalvular atrial fibrillation (CNVAF). A Markov decision-analytic model was used to compare three treatment strategies for CNVAF: 1) warfarin; 2) aspirin; and 3) no treatment. Five-year quality-adjusted life years (QALYs) were calculated for male and female cohorts aged 70 and 75 years. In the baseline analysis (effectiveness of warfarin = 0.70, effectiveness of aspirin = 0.45, utility of warfarin = 0.99, and utility of aspirin = 0.999) the quality-adjusted survival rates for 70-year-old males were 4.03 QALYs on warfarin, 4.02 QALYs on aspirin, and 3.95 QALYs on no treatment. Results were similar for all age and sex cohorts. Sensitivity analyses revealed that the results were very sensitive to the effec tiveness of aspirin and the disutility of warfarin. The authors conclude that the optimal strategy for the treatment of CNVAF in elderly patients varies with the disutility assigned to warfarin therapy and the effectiveness value for aspirin therapy. Key words: chronic atrial fibrillation; elderly; anticoagulation; warfarin; aspirin; decision analysis; Markov analysis; quality of life. (Med Decis Making 1992;12:239-249)

This paper examines the economic attractiveness of universal vaccination of infants with hepatitis B virus (HBV) vaccine by calculating the incremental cost-effectiveness of this strategy when compared with the currently recommended strategy of screening all pregnant women and vaccinating only infants born to HBsAg+ mothers. A decision-analytic model involving a Markov process to model the long-term sequelae of HBV infection was constructed to estimate the expected costs and life expectancies for a cohort of newborns under two strategies: the current screening policy (SELECTIVE), which involves active and passive vac cination of infants born to carrier mothers, and a policy that combines the current screening strategy (including active and passive vaccination of infants born to carriers) with active vaccination alone for children of non-carriers (UNIVERSAL). A hypothetical cohort of children born in either Canada or the United States in 1991 was examined. Cost estimates were derived for Ontario. From a societal perspective, the incremental cost required to achieve one extra life year was found to be $30,347, comparable to the cost-effectivenesses of other health care strategies commonly used in North America. The result is sensitive to the duration of vaccine effectiveness and particularly to the price of the vaccine. Universal vaccination results in net cost saving at a vaccine price of approximately $7 per dose, from a societal perspective. It is concluded that universal vaccination against HBV in infancy is economically attractive, comparable in cost-effectiveness to existing health care interven tions. Lower vaccine prices would substantially improve the attractiveness of such a program. Implementation of universal vaccination should be considered in North America, contingent on vaccine price reduction. A monitoring program to ensure the long-term efficacy of the vaccine should be part of such a program. Key words: vaccination; hepatitis B; cost-effec tiveness; prevention; chronic hepatitis. (Med Decis Making 1993;13:4-20)

BACKGROUND: Because of the prevalence of pneumococcal pneumonia, the substantial morbidity and mortality associated with many pneumococcal infections, and an increase in the incidence of antibiotic resistance among pneumococcal isolates, considerable efforts for disease prevention have been made using a polyvalent polysaccharide pneumococcal vaccine. Despite numerous clinical trials of the vaccine, its efficacy in the prevention of pneumococcal infections and other clinically relevant medical outcomes in adults remains uncertain. METHODS: To assess quantitatively the efficacy of pneumococcal vaccination, a MEDLINE literature search, manual reviews of article bibliographies, and communications with pneumococcal vaccine investigators were used to identify randomized controlled trials of the pneumococcal vaccine. Independent review of 594 articles revealed nine randomized trials with 12 vaccine and control study groups that evaluated clinically relevant outcomes in adults. To estimate a summary effect size for all outcomes, Mantel-Haenszel odds ratios (ORs) and Dersimonian and Laird rate differences (RDs) and their associated 95% confidence intervals (CIs) were computed. RESULTS: Summary ORs demonstrated a statistically significant protective effect of the vaccine for four pneumococcal infection—related outcomes: definitive pneumococcal pneumonia (OR=0.34; 95% CI=0.24 to 0.48), definitive pneumococcal pneumonia for vaccine-containing pneumococcal antigen types only (vaccine types only) (OR=0.17; 95% CI=0.09 to 0.33), presumptive pneumococcal pneumonia (OR=0.47; 95% CI=0.35 to 0.63), and presumptive pneumococcal pneumonia (vaccine types only) (OR=0.39; 95% CI=0.26 to 0.59). The summary RDs, which account for heterogeneity among studies, confirmed a statistically significant protective effect for two of these same outcomes: definitive pneumococcal pneumonia (RD=4/1000; 95% CI=0/1000 to 7/1000) and definitive pneumococcal pneumonia (vaccine types only) (RD=8/1000; 95% CI=1/1000 to 16/1000). Summary ORs and RDs failed to demonstrate a protective effect for pneumonia (all causes), bronchitis, and mortality (all causes) or mortality due to pneumonia or pneumococcal infection. Subgroup analyses showed that for all four pneumococcal infection—related outcomes, vaccine efficacy differed for high- and low-risk subjects, demonstrating efficacy for low-risk subjects and lack of efficacy for high-risk subjects. CONCLUSIONS: Pneumococcal vaccination appears efficacious in reducing bacteremic pneumococcal pneumonia in low-risk adults. However, evidence from randomized controlled trials fails to demonstrate vaccine efficacy for pneumococcal infection-related or other medical outcomes in the heterogeneous group of subjects currently labeled as high risk.(Arch Intern Med. 1994;154:2666-2677)

• In this article, we describe a multifactorial cardiac risk index that can be used to assess patients undergoing noncardiac surgery. The index is a modified version of an index that was previously generated by Goldman and coworkers on a set of 1001 consecutive patients and prospectively validated in our clinical setting (a general medical consultation service in a large teaching hospital) on 455 patients. We present a Bayesian approach to assessing cardiac risks by converting average risks for patients undergoing particular surgical procedures (pretest probabilities) to average risks for patients with each index score (posttest probabilities). A simple nomogram is presented for performing such a calculation.(Arch Intern Med 1986;146:2131-2134)

• "Negative" clinical trials that conclude that neither of the treatments is superior are often criticized for having enrolled too few patients. These criticisms usually are based on formal sample size calculations that compute the numbers of patients required prospectively, as if the trial had not yet been carried out. We suggest that this "prospective" sample size calculation is incorrect, for once the trial is over we have "hard" data from which to estimate the actual size of the treatment effect. We can either generate confidence limits around the observed treatment effect or retrospectively compare it with the effect hypothesized before the trial. If the observed effect is small, the risk of the false-negative conclusion (and the sample size required to draw negative or equivalency conclusions) is often much less than that generated by the "prospective" calculation.(Arch Intern Med 1985;145:709-712)