Examining the correlation between treatment effects in clinical trials and economic modeling.

INTRODUCTION: Many diseases have a sequential treatment pathway. Compared with patients without previous treatment, patients who fail initial treatment may have lower success rates with a second treatment. This phenomenon can be explained by a correlation between treatment effects. METHODS: We developed a statistical model of covariance for the underlying unobserved correlation between treatments and established a mathematical expression for the magnitude of the latent correlation term. We conducted a simulation study of clinical trials to investigate the correlation between two treatments and explored clinical examples based on published literature to illustrate the identification and evaluation of these correlations. RESULTS: Our simulation study confirmed that a treatment correlation reduces the probability of success for the second treatment, compared with no correlation. We found that treatment correlations may be observable in clinical trials, such as for depression and lung cancer, and the magnitude of correlation may be estimated. We illustrated that treatment correlations can be incorporated into an economic model, with possible impacts on cost-effectiveness results. Additional applications of correlation concepts are also discussed. CONCLUSIONS: We evaluated the correlation between treatment effects and our approach can be applied to clinical trial design and economic modeling of sequential clinical treatment pathways.

Agreement in reporting between trial publications and current clinical trial registry in high impact journals: A methodological review.

OBJECTIVES: The primary objective of this systematic survey was to examine the percentage of studies in which there was agreement in the reporting of the primary outcome between the currently updated version of the clinical trial registry and the published paper. We also investigated the factors associated with agreement in reporting of the primary outcome. METHODS: We searched PubMed for all randomized control trials (RCT)s published in 2012-2015 in the top five general medicine journals (based on the 2014 impact factor). Two hundred abstracts (50 from each year) were randomly selected for data extraction. Agreement in reporting of 11 key study conduct items (e.g., sample size) and study characteristics (e.g., funding, number of sites) were extracted by two independent reviewers. ANALYSIS: Descriptive analyses were conducted to determine the proportion of studies on which there was agreement in reporting of key study conduct items. Generalized estimating equations were used to explore factors associated with agreement in reporting of the primary outcome. RESULTS: Of the 200 included studies, 87% had agreement in reporting of the primary outcome. After adjusting for other covariates, having greater than 50 sites was associated with an increased likelihood of agreement in reporting of the primary outcome (odds ratio=7.1, 95% confidence interval=1.39, 36.27, p=0.018). CONCLUSIONS: We identified substantive disagreement in reporting between publications and current clinical trial registry, which were associated with several study characteristics. Further measures are needed to improve reporting given the potential threats to the quality and integrity of scientific research.

Barriers and facilitators of thromboprophylaxis for medical-surgical intensive care unit patients: a multicenter survey.

BACKGROUND: The objective of this study was to identify the self-reported barriers to and facilitators of prescribing low-molecular-weight heparin (LMWH) thromboprophylaxis in the intensive care unit (ICU). METHODS: We conducted an interviewer-administered survey of 4 individuals per ICU (the ICU director, a bedside pharmacist, a thromboprophylaxis research coordinator, and physician site investigator) regarding LMWH thromboprophylaxis for medical-surgical patients in 27 ICUs in Canada and the United States. Items were generated by the research team and adapted from previous surveys, audits, qualitative studies, and quality improvement research. Respondents rated the barriers to LMWH use, facilitators (effectiveness, affordability, and acceptability thereof), and perceptions regarding LMWH use. RESULTS: Respondents had 14.5 (SD, 7.7) years of ICU experience (response rate, 99%). The 5 most common barriers in descending order were as follows: drug acquisition cost, fear of bleeding, lack of resident education, concern about bioaccumulation in renal failure, and habit. The top 5 rated facilitators were preprinted orders, education, daily reminders, audit and feedback, and local quality improvement committee endorsement. Centers using preprinted orders (mean difference [P<.01]) and computerized physician order entry (P<.01) compared with those centers not using those tools reported higher affordability for these 2 facilitators. Compared with physicians and pharmacists, research coordinators considered ICU-specific audit and feedback of thromboprophylaxis rates to be a more effective, acceptable, and affordable facilitator (odds ratio, 6.67; 95% confidence interval, 1.97-22.53; P<.01). Facilitator acceptability ratings were similar within centers but differed across centers (P≤.01). CONCLUSIONS: This multicenter survey found several barriers to use of LMWH including cost, concern about bleeding, and lack of resident knowledge of effectiveness. The diversity of reported facilitators suggests that large scale programs may address generic barriers but also need site-specific interprofessional knowledge translation activities.

A sensitivity analysis of the Children's Treatment Network trial: a randomized controlled trial of integrated services versus usual care for children with special health care needs.

BACKGROUND: The value of integrated care through comprehensive, coordinated, and family-centered services has been increasingly recognized for improving health outcomes of children with special health care needs (CSHCN). In a randomized controlled trial (RCT), the integrated care provided through the Children's Treatment Network (CTN) was compared with usual care in improving the psychosocial health of target CSHCN. In this paper, we aimed to estimate the effect of CTN care by conducting multiple analyses to handle noncompliance in the trial. METHODS: The trial recruited target children in Simcoe County and York Region, ON, Canada. Children were randomized to receive CTN or usual care and were followed for 2 years. The CTN group received integrated services through multiple providers to address their specific needs while the usual care group continued to receive care directed by their parents. The outcome was change in psychosocial quality of life at 2 years. We conducted intention-to-treat, as-treated, per-protocol, and instrumental variable analyses to analyze the outcome. RESULTS: The trial randomized 445 children, with 229 in the intervention group and 216 in the control group. During follow-up, 52% of children in the intervention group did not receive complete CTN care for various reasons. At 2 years, we did not find a significant improvement in psychosocial quality of life among the children receiving CTN care compared with usual care (intention-to-treat mean difference 1.50, 95% confidence interval -1.49 to 4.50; P = 0.32). Other methods of analysis yielded similar results. CONCLUSION: Although the effect of CTN care was not significant, there was evidence showing benefits of integrated care for CSHCN. More RCTs are needed to demonstrate the magnitude of such an effect. The CTN study highlights the key challenges in RCTs when assessing interventions involving integrated care, and informs further RCTs including similar evaluations.