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Biomedical subjects

Scott D Halpern

Publications and source records attributed to Scott D Halpern.

27 records · Page 2Linked to original sources
PubMed2003

Smallpox vaccination: a national survey of emergency health care providers.

UNLABELLED: Concerns about bioterrorism have prompted a national voluntary smallpox (SP) vaccination program in the United States. Although emergency health care providers are among the first targeted for vaccination, little is known about how these providers view the risks and benefits of SP vaccination. OBJECTIVES: To assess the willingness of emergency health care personnel to receive pre-event SP vaccination prior to the start of the national program. METHODS: The authors conducted a national cross-sectional, anonymous survey of 1,701 emergency physicians, nurses, and mid-level practitioners working full time in 13 adult and pediatric academic emergency departments in large U.S. cities in November and December 2002. The main outcome measure was willingness to be vaccinated against SP. Secondary outcomes included the prevalence of self-reported contraindications, and reasons for and against vaccination. RESULTS: 732 emergency health care providers returned questionnaires (response rate 43%). Overall, 73% (95% CI = 66% to 80%) were willing to receive pre-event SP vaccination. 18% (95% CI = 14% to 23%) reported contraindications to vaccination, and 50% (95% CI = 39% to 61%) of these providers were willing to receive pre-event SP vaccination. Self-protection (72%) was the most common reason cited for desiring vaccination against SP; concern about vaccine-related adverse events (54%) was the most common reason cited for not wanting immunization. CONCLUSIONS: Most emergency health care providers express a willingness to receive pre-event SP immunization; self-protection is a principal motivating reason. A subset of health care providers, however, may place themselves at increased risk by desiring vaccination despite contraindications.

Adult↗
PubMed2002

The continuing unethical conduct of underpowered clinical trials.

Despite long-standing critiques of the conduct of underpowered clinical trials, the practice not only remains widespread, but also has garnered increasing support. Patients and healthy volunteers continue to participate in research that may be of limited clinical value, and authors recently have offered 2 related arguments to support the validity and value of underpowered clinical trials: that meta-analysis may "save" small studies by providing a means to combine the results with those of other similar studies to enable estimates of an intervention's efficacy, and that although small studies may not provide a good basis for testing hypotheses, they may provide valuable estimates of treatment effects using confidence intervals. In this article, we examine these arguments in light of the distinctive moral issues associated with the conduct of underpowered trials, the disclosures that are owed to potential participants in underpowered trials so they may make autonomous enrollment decisions, and the circumstances in which the prospects for future meta-analyses may justify individually underpowered trials. We conclude that underpowered trials are ethical in only 2 situations: small trials of interventions for rare diseases in which investigators document explicit plans for including their results with those of similar trials in a prospective meta-analysis, and early-phase trials in the development of drugs or devices, provided they are adequately powered for defined purposes other than randomized treatment comparisons. In both cases, investigators must inform prospective subjects that their participation may only indirectly contribute to future health care benefits.

Bias↗
PubMed2002

Prospective preference assessment: a method to enhance the ethics and efficiency of randomized controlled trials.

The concomitant problems of underenrollment and selective enrollment limit the efficiency of many randomized controlled trials (RCTs). In addition, the traditional informed consent process is often inadequate to respect research participants' autonomy. Past efforts to overcome these problems are not universally applicable. A new method, called prospective preference assessment (PPA), is suggested as a way to simultaneously enhance participant accrual, identify groups of patients to whom a trial's results may apply, and promote participants' interests. PPA is a method by which investigators would evaluate potential trial participants' motivations for and concerns about enrolling in a planned trial prior to formal recruitment. The information provided by PPA would then be used to (1) modify the final trial design and conduct to make enrollment more attractive, and (2) identify ways in which the patients who do enroll may differ from those who do not, thereby elucidating the trial's generalizability. The methodologic and ethical advantages of this method are described, and potential barriers to the method's implementation are addressed. The added costs of prospectively assessing the views of potential research participants prior to initiating RCTs are considered in relation to the method's ability to enhance the value of the information to be obtained. It is concluded that PPA is a feasible approach to a more democratic and efficient research process and that its adoption would be consistent with current trends in health care.

Human Experimentation↗
PubMed2002

Physicians' preferences for active-controlled versus placebo-controlled trials of new antihypertensive drugs.

OBJECTIVE: To evaluate physicians' preferences for referring patients to, and using information from, active-controlled trials (ACTs) versus placebo-controlled trials (PCTs) of new antihypertensive drugs. DESIGN AND SETTING: Nationwide mailed survey, with telephone contact of nonresponders to assess nonresponse bias. PARTICIPANTS: One thousand two hundred primary care physicians randomly selected from the American Medical Association's Master File. Of 1,154 physicians eligible to respond, 651 (56.4%) returned completed questionnaires. MEASUREMENTS AND MAIN RESULTS: We measured physicians' stated willingness to encourage hypertensive patients to enroll in ACTs and PCTs of new antihypertensive drugs, their views of the relative merits of ACTs versus PCTs, their stated willingness to prescribe new drugs tested in ACTs or PCTs, and their views regarding the overall justifiability of the 2 designs. Physicians were significantly more likely to indicate they would encourage their patients to enroll in ACTs than in PCTs (P <.0001). Physicians thought ACTs provided more valuable information for their practices, were more likely to lead to a public health benefit, offered enrolled patients greater opportunity for personal benefit, and were less likely to expose enrolled patients to unnecessary risks (all P <.0001). Physicians were more likely to prescribe new drugs that had been compared in ACTs (P <.0001), and viewed ACTs as a more justifiable method for testing new antihypertensive drugs (P <.0001). There was no evidence of nonresponse bias for these main results. CONCLUSIONS: Although PCTs remain the standard method for testing new antihypertensive drugs, physicians strongly prefer ACTs. Using ACTs to test new antihypertensive drugs may enhance the efficiency of patient recruitment and more strongly influence physicians' prescribing practices.

Antihypertensive Agents↗
PubMed2002

Randomized trial of 5 dollars versus 10 dollars monetary incentives, envelope size, and candy to increase physician response rates to mailed questionnaires.

BACKGROUND: The validity of the results of mailed surveys is often threatened by nonresponse bias, which is made more likely when response rates are low. However, the effectiveness and cost-effectiveness of several strategies to increase response rates are uncertain. OBJECTIVES: To assess three strategies to increase response rates to mailed physician surveys: including a 10 dollars versus a 5 dollars cash incentive in the initial mailing, including a mint candy or not, and using a large versus small outgoing envelope. RESEARCH DESIGN AND SUBJECTS: Using a 2 x 2 x 2 factorial design, a randomized trial of these strategies was conducted in a survey of 1200 physicians randomly selected from the American Medical Association's Master File. RESULTS: Including a 10 dollars incentive yielded a significantly higher response rate (60.5% vs. 52.8%) (P = 0.009). The mailing and incentive costs per completed response were 12.24 dollars (95% CI, 11.75 dollars, 13.64 dollars) in the 5 dollars group and 18.48 dollars (95% CI, 17.77 dollars, 20.69 dollars) in the 10 dollars group. Each additional response obtained in the 10 dollars group came at an incremental cost of 61.26 dollars (95% CI, 36.98 dollars, 200.80 dollars). Neither inclusion of a mint nor use of a large envelope influenced the response rate. CONCLUSIONS: Investigators may increase response rates by including more money in the initial questionnaire packet, but there may be diminishing returns to serial increments in incentives greater than 5 dollars. Including smaller incentives in more questionnaires may maximize total responses.

Candy↗