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Scott D Halpern

Publications and source records attributed to Scott D Halpern.

At least 19 recordsLinked to original sources
PubMed2006

Inadequate hepatitis B vaccination and post-exposure evaluation among transplant surgeons: prevalence, correlates, and implications.

OBJECTIVES: To identify the proportion of U.S. transplant surgeons who are adequately vaccinated against hepatitis B virus (HBV), identify characteristics associated with inadequate vaccination, and assess the proportion who had been evaluated for immunization following potential HBV exposures. SUMMARY BACKGROUND DATA: It is unknown what proportion of transplant surgeons are appropriately vaccinated against HBV or evaluated for immunization following operative exposures. METHODS: We mailed questionnaires and to all active U.S. transplant surgeons. We compared demographic characteristics of responders and nonresponders to evaluate the potential for nonresponse bias. RESULTS: Of 619 eligible respondents, 347 (56.1%) returned completed questionnaires. Of the 311 surgeons for whom HBV vaccination was indicated (all surgeons with neither a prior history of HBV infection nor a prior adverse reaction to the vaccine itself), 70 (22.5%; 95% confidence interval [CI], 18.0-27.6%) received fewer than the recommended 3 injections. Surgeon characteristics associated with inadequate vaccination included length of clinical practice (odds ratio [OR], 1.5 per 10-year increment in duration of practice; 95% CI, 1.1-2.2), increased fear of infection (OR, 1.2 for each unit increase in fear out of 10; 95% CI, 1.1-1.4), and lack of recent testing for HBV infection (OR, 2.0; 95% CI, 1.1-3.8). Of the 94 surgeons (27.3%) reporting at least one needle-stick exposure while operating on an HBV-infected patient, 14 (14.9%) were inadequately vaccinated; of these 14, only 5 (35.7%) sought appropriate serologic testing and counseling for active immunization. Surgeons underestimated both the risks of percutaneous exposure while operating, and of becoming infected with HBV if exposed. CONCLUSIONS: Many transplant surgeons are inadequately vaccinated against HBV and fail to seek evaluation following possible exposures. Underestimation of the risks of HBV exposure and transmission may relate to these failures. Requiring documentation of HBV vaccination and immunity to maintain operating room privileges may protect surgeons, their patients, and operating room staff.

Attitude of Health Personnel↗
PubMed2005

Epidemiologic studies of adverse effects of anti-retroviral drugs: how well is statistical power reported.

PURPOSE: To determine whether there is a difference in average statistical power between pharmacoepidemiologic studies of anti-retroviral adverse drug effects (ADEs) sponsored by for-profit versus non-profit organizations. METHODS: We studied all published pharmacoepidemiologic studies of ADEs associated with the 15 anti-retroviral drugs approved through the end of 1999. A priori, the primary outcome was the power of each study to detect a clinically important difference in the risk for an adverse effect among patients exposed to the study drug(s). We could not evaluate this outcome because of the infrequent reporting of power calculations. We instead report the distribution of studies across a 5-tiered measure of adequacy of reporting of statistical power, as well as the sponsorship of these studies. RESULTS: Of 48 studies meeting our inclusion criteria, only 1 (2%) reported either a completed, a priori power calculation or sufficient details for readers to calculate the power to detect a pre-defined, clinically important effect. Thirty-five studies (73%) reported the minimum information required for sophisticated readers to determine the power to detect an event rate of interest to them; 6 additional studies (13%) reported confidence intervals around at least one summary effect measure and 6 (13%) provided no indication of power or uncertainty. Of the 41 studies for which sponsorship was determined, only 3 (7%) were sponsored by for-profit organizations. CONCLUSIONS: The poor reporting of statistical power in this sample suggests a need for guidelines to improve the reporting of pharmacoepidemiologic studies of ADEs. Future research is needed to determine whether the observed paucity of industry-sponsored observational studies of anti-retroviral ADEs extends to other clinical areas, and if so, to identify the causes of this phenomenon.

Adverse Drug Reaction Reporting Systems↗
PubMed2005

Incentive models to increase living kidney donation: encouraging without coercing.

Kidney transplantation is a superior treatment strategy than chronic dialysis for end-stage renal disease patients. However, there is a severe shortage of cadaveric kidneys that are available for transplantation. Therefore many patients are turning to living donors. We describe four models of incentives to improve rates of living kidney donation: the market compensation model, the fixed compensation model, no-compensation model and the expense reimbursement model. We discuss the advantages and disadvantages of each of these models. Any incentive to improve rates of living kidney donation must be accompanied by safeguards. These safeguards will prevent living donors from being viewed primarily as a resource for transplants. These safeguards will also prevent vulnerable individuals from being coerced into donation and will monitor long-term outcomes of donors using a donor registry. We recommend the use of the expense reimbursement model along with these safeguards, in order to increase rates of living kidney donation.

Humans↗
PubMed2005

Determinants of transplant surgeons' willingness to provide organs to patients infected with HBV, HCV or HIV.

The common provision of organs to patients infected with hepatitis B virus (HBV) and hepatitis C virus (HCV), but not to those infected with human immunodeficiency virus (HIV), has been attributed to perceived or real differences in transplantation efficacy among these populations. However, other explanations remain possible. We surveyed all active U.S. transplant surgeons to identify determinants of their views of the propriety of transplantation among HBV-, HCV-, and HIV-infected patients. The 347 surgeons (56.1%) returning completed questionnaires believed that HCV- and HIV-infected patients have similar post-transplant survival (p = 0.9), but that both groups fare worse than HBV-infected patients (p < 0.00001 for both comparisons). Most transplant surgeons considered HBV- and HCV-infected patients to be appropriate transplantation candidates (p = 1.0 for this comparison), whereas one-third considered HIV-infected patients to be appropriate candidates (p < 0.00001 when compared with HBV- or HCV-infected patients). That surgeons are generally willing to transplant HCV-infected patients but not HIV-infected patients, and yet believe these groups will have similar post-transplant survival, suggests that survival estimates alone do not explain surgeons' choices. HIV-infected patients should have equal access to organs unless or until evidence emerges that they fare substantially worse than other potential recipients.

Attitude of Health Personnel↗
PubMed2004

Willingness of patients to switch from conventional to daily hemodialysis: looking before we leap.

PURPOSE: To evaluate the willingness of patients with end-stage renal disease to switch from conventional hemodialysis to short daily hemodialysis, and to determine what health benefits clinical trials of daily hemodialysis would have to document for patients to switch regimens. METHODS: We studied all patients receiving conventional hemodialysis (defined as three times per week) at three dialysis centers in Philadelphia during a 4-month period. Patients indicated their willingness to switch to daily hemodialysis (defined as six 2- to 3-hour in-center treatments per week) in each of 21 scenarios presented via an interactive computer display. We used conjoint analysis to determine how patients' decisions were influenced by four attributes of daily hemodialysis: predicted life expectancy, quality of life, number of annual hospitalizations, and weekly transportation time to and from the dialysis center. RESULTS: Of 126 patients interviewed, 55 (44%) would not choose daily hemodialysis regardless of its health benefits. The remaining 71 patients (56%) indicated that they would consider switching if daily hemodialysis was shown to yield certain health benefits. Patients were more willing to switch to daily hemodialysis as the associated life expectancy and average quality of life increased, and as the number of annual hospitalizations and weekly transportation time decreased (all P <0.001). CONCLUSION: Although daily hemodialysis has received broad support from nephrologists, funding agencies, and lawmakers as the emerging standard of care for patients with end-stage renal disease, upcoming clinical trials would have to document substantial health benefits in order for patients to switch to daily hemodialysis, and many patients may still decline this regimen regardless of the documented benefits.

Adult↗
PubMed2004

Empirical assessment of whether moderate payments are undue or unjust inducements for participation in clinical trials.

BACKGROUND: Paying patients to participate in clinical trials is ethically controversial. However, there has been no empirical documentation regarding whether payment represents an undue or unjust inducement. METHODS: To evaluate these questions, we described hypothetical placebo-controlled trials of a new antihypertensive drug to 126 patients with mild-to-moderate hypertension recruited from hypertension and general medicine clinics at a university hospital. Using a 3 x 3, within-subjects design, we altered a risk to participation (either adverse effect rate or rate of randomization to placebo) and the payment participants would receive ($100, $1000, and $2000) and asked patients to indicate their willingness to participate (WTP) in each trial using a 6-point scale. RESULTS: Clustered ordinal logistic regression models revealed that patients' WTP decreased with higher risk of adverse effects (P<.001), higher risk of being assigned to placebo (P =.02), and lower payment level (P<.001). There were no significant interactions between payment level and either risk variable, suggesting that increasing payments do not alter peoples' perceptions of risk. There was a trend toward a positive interaction between income and the influence of payment on WTP (P =.09), suggesting that payment more strongly influences WTP among wealthier people. Wealthier patients were more likely to state that payment was important in their participation decision (37% vs 20%, P =.05). CONCLUSION: Although higher payment motivates research participation, we found no evidence that commonly used payment levels represent undue or unjust inducements.

Antihypertensive Agents↗
PubMed2004

Preevent vaccination against smallpox: a survey of pediatric emergency health care providers.

BACKGROUND: In January 2003, smallpox vaccinations were offered to health care workers to create hospital-based teams prepared to care for patients with smallpox as part of national bioterrorism preparedness activities. METHODS: An anonymous survey of pediatric emergency health care workers was conducted in November and December 2002. Two mailings were sent to physicians, nurses and ancillary staff at five academic pediatric emergency departments in major US cities. We assessed the willingness to receive preevent smallpox vaccine. In addition we measured the prevalence of vaccine contraindications, perceived likelihoods of a local smallpox outbreak or a vaccine-related adverse event and reasons for or against wanting to receive the vaccine. RESULTS: Overall 72% of respondents were willing to receive the smallpox vaccine. Individuals who were willing to receive the smallpox vaccine, compared with those not willing, believed a local outbreak was more likely to occur (odds ratio, 1.29; 95% confidence interval, 1.16 to 1.44). One-fifth of respondents reported a contraindication to smallpox vaccine; however, more than half indicated they would still be willing to receive vaccine. Individuals who perceived themselves at high risk for vaccine-related adverse events were less willing to receive the preevent smallpox vaccine. Self-protection was the most common reason cited for wanting to receive the vaccine. CONCLUSIONS: A majority of pediatric healthcare workers were willing to receive preevent smallpox vaccine before the onset of Phase I of the CDC Smallpox Vaccination Program. A greater understanding of the knowledge, attitudes and beliefs of pediatric health care workers toward preevent smallpox vaccination will assist in the development of future bioterrorism preparedness programs.

Attitude of Health Personnel↗
PubMed2004

Willingness of dialysis patients to participate in a randomized controlled trial of daily dialysis.

BACKGROUND: The National Institutes of Health (NIH) has proposed conducting randomized controlled trials comparing short, daily, in-center hemodialysis with conventional hemodialysis. However, there is concern that difficulties recruiting patients may prevent the successful completion of such trials if patients believe the inconveniences of daily dialysis outweigh any potential health benefits. METHODS: To gauge willingness to participate in a daily dialysis trial, we described a hypothetical, randomized controlled trial comparing conventional to daily hemodialysis to 209 chronic hemodialysis patients, and assessed their motivations for and concerns about participating. RESULTS: We found that 85 patients (41%) of 209 patients who agreed to be interviewed expressed some willingness to participate in the hypothetical trial. Patients who expressed greater willingness to participate were younger (OR for participating = 0.96 per year, 95% CI = 0.94 to 0.98, P= 0.001), less likely to smoke (OR = 0.38, 95% CI = 0.17 to 0.84, P= 0.017), more likely to have been hospitalized during the last 12 months (OR = 2.8, 95% CI = 1.5 to 5.5, P= 0.002), less likely to have reactive airway disease (OR = 0.21, 95% CI = 0.06 to 0.69, P= 0.01) or coronary artery disease (OR = 0.20, 95% CI = 0.08 to 0.53, P= 0.001), and less likely to be on the waiting list for a kidney transplant (OR = 0.23, 95% CI = 0.10 to 0.50, P < 0.0001). CONCLUSION: The study suggests that less than half of eligible patients would be willing to participate in the randomized controlled trial. Differing willingness to participate across patient subgroups suggests that certain subgroups (i.e., older patients and those with coronary artery disease) will need to be targeted to ensure that results are generalizable to most hemodialysis patients.

Adult↗
PubMed2003

Hypertensive patients' willingness to participate in placebo-controlled trials: implications for recruitment efficiency.

BACKGROUND: Underenrollment and selective enrollment plague many clinical trials. Little is known about why hypertensive patients agree or refuse to participate in placebo-controlled trials (PCT) of antihypertensive drugs, whether the prospect of receiving placebo influences willingness to participate (WTP), or whether patients who participate differ from those who do not. METHODS: We described a hypothetical PCT of a new antihypertensive drug to 126 patients who would be eligible for ongoing phase III trials. We solicited patient motivations and concerns regarding trial participation by using open-ended questions, assessed the patients' stated WTP, and used logistic regression to determine patient characteristics associated with WTP. We reassessed WTP in 62 patients after revealing, in random order, that 10%, 30%, and 50% of patients would receive placebo. RESULTS: The most commonly cited motivations for participating included personal health benefits (40%), helping other patients (37%), and contributing to scientific knowledge (15%). The most common concerns were having to stop current medications (56%), inconvenience/annoyance (38%), fear of known side effects (35%), and the possibility of receiving placebo (24%). Overall, 47% of patients (95% confidence interval, 38% to 56%) were willing to participate. Younger patients (57% versus 37%; P =.01), nonsmokers (50% versus 24%; P =.04), and patients who had participated in research previously (77% versus 20%; P =.009) were all significantly more willing to participate. Fewer patients were willing to participate as the percentage who would receive placebo increased (P =.02), but randomly assigning fully half of patients to placebo still yielded maximal recruitment efficiency. CONCLUSIONS: Hypertensive patients participate in trials for altruistic and personal health reasons. Differences between patients who do or do not participate may influence trial outcomes. The proportion of patients receiving placebo influences some patients' enrollment decisions but is not a key determinant of recruitment efficiency.

Altruism↗
PubMed2003

Evaluating preference effects in partially unblinded, randomized clinical trials.

The ability of randomized, clinical trials (RCTs) to produce unbiased estimates of an intervention's specific (i.e., innate pharmacologic or physiologic) effect rests on at least two assumptions. First, other prognostic effects (such as disease severity or the psychologic effects of treatment) are assumed to be evenly distributed across treatment groups, and second, it is assumed that these other effects do not interact with the intervention's specific effect. This essay shows how the effect of patients' preferences for treatments may interact with an intervention's specific effect to bias the trial's results. Earlier mathematical descriptions of how preference effects may produce bias in nonblinded trials are extended to the case of (presumably) blinded RCTs. The extent to which preference effects may confer bias in partially unblinded placebo-controlled vs. active-controlled drug trials are considered. Finally, methods for estimating preference effects in partially unblinded RCTs are provided. It is concluded that investigators could use these methods to quantify potential preference effects in partially unblinded RCTs, and thereby more accurately estimate the specific effects of treatments.

Double-Blind Method↗