Some t-tests for N-of-1 trials with serial correlation

N-of-1 trials allow inference between two treatments given to a single individual. Most often, clinical investigators analyze an individual's N-of-1 trial data with usual t-tests or simple nonparametric methods. These simple methods do not account for serial correlation in repeated observations coming from the individual. Existing methods accounting for serial correlation require simulation, multiple N-of-1 trials, or both. Here, we develop t-tests that account for serial correlation in a single individual. The development includes effect size and precision calculations, both of which are useful for study planning. We then evaluate and compare their Type I and II errors and interval estimators to those of usual t-tests analogues via Monte Carlo simulation. The serial t-tests clearly outperform the usual t-tests commonly used in reporting N-of-1 results. Examples from N-of-1 clinical trials in fibromyalgia patients and from a behavioral health setting exhibit how accounting for serial correlation can change inferences. These t-tests are easily implemented and more appropriate than simple methods commonly used; however, caution is needed when analyzing only a few observations. Keywords: Autocorrelation; Cross-over studies; Repeated measures analysis; Single-case experimental design; Time-seriesComment: 23 pages, 6 figures, 6 table

COVID-19 Mortality Rates are Higher among People with Intellectual and Developmental Disability

Despite higher risk of severe outcomes from COVID-19 among people with intellectual and developmental disabilities (IDD), there has been limited reporting of COVID-19 trends for this population. This research brief shows that higher COVID-19 case fatality rates among people with IDD. Risk is especially high among people are younger ages

New Approach to Overcoming the Insurmountable Watershed Rule Exception to Teague\u27s Collateral Review Killer, A

This Article will propose a new approach to overcoming the seemingly insurmountable watershed rule exception. While a single case - such as Crawford or Blakely - may not rise to watershed status, this Article will suggest that a line of cases could be considered watershed. 8 It will be shown that the highly subjective nature of this exception lends itself perfectly to this type of reasoning, and that adoption of this approach would help reconcile some inherent conflicts encountered by the Court whenever Teague retroactivity comes before it. Part II of this Article will provide the necessary legal framework, by tracing habeas corpus and the issue of retroactivity from the writ\u27s origins through Teague and its aftermath. Part III will then propose the above mentioned line of cases approach and consider its potential in light of the Court\u27s recent holdings in Whorton v. Bockting and Burton v. Stewart. Finally, Part IV will conclude the Article

New Approach to Overcoming the Insurmountable Watershed Rule Exception to Teague\u27s Collateral Review Killer, A

This Article will propose a new approach to overcoming the seemingly insurmountable watershed rule exception. While a single case - such as Crawford or Blakely - may not rise to watershed status, this Article will suggest that a line of cases could be considered watershed. 8 It will be shown that the highly subjective nature of this exception lends itself perfectly to this type of reasoning, and that adoption of this approach would help reconcile some inherent conflicts encountered by the Court whenever Teague retroactivity comes before it. Part II of this Article will provide the necessary legal framework, by tracing habeas corpus and the issue of retroactivity from the writ\u27s origins through Teague and its aftermath. Part III will then propose the above mentioned line of cases approach and consider its potential in light of the Court\u27s recent holdings in Whorton v. Bockting and Burton v. Stewart. Finally, Part IV will conclude the Article

Major Causes of Death among Adults with Down Syndrome

Adults with Down syndrome often die at earlier ages than their peers in the general population. This data slice describes increased risk of death across different age groups from Dementia/Alzheimer’s, Influenza/Pneumonia, and Pneumonitis for adults with Down syndrome

NONLINEAR REGRESSION PARAMETERS AS OUTCOMES: SIMPLE VS. SOPHISTICATED ANALYSES

Sometimes a nonlinear regression parameter for an individual is the outcome of interest. But due to variability among individuals, the individuals’ regression parameters cannot be estimated with the same amount of precision. This problem of heterogeneous variance complicates the ultimate goal of estimating population-level regression parameters with two usual methods: (i) the simple arithmetic mean of individually estimated regression parameters and (ii) random coefficients regression (RCR). Weights are proposed for each method to account for the heterogeneity problem. The methods are illustrated with chick weights collected over time. Monte Carlo simulation allows comparison of statistical properties of the four estimators for small, moderate and large sample sizes. The arithmetic means tended to outperform the RCR estimators with respect to mean square error and bias; and their associated confidence intervals held nominal levels. Actual coverage of confidence intervals produced from RCR methods fell below nominal levels in some cases; however this discrepancy may be an algorithm error. Overall, the simpler arithmetic mean estimators tend to have either better or comparable statistical properties to those estimators from RCR methods

Increased COVID-19 Risk for Adults with Intellectual and/or Developmental Disability Living in Residential Group Homes

Adults with intellectual and/or developmental disability living in group homes in New York are at higher risk of severe COVID-19 outcomes, including death

What are we hiding? Preventable causes of death are not accurately counted for adults with intellectual disability

This research brief reports on findings from a recent research on errors in cause of death reporting on death certificates for individuals with disabilities. Analyzing the death certificates of over 30,000 adults with developmental disabilities who died between 2012 and 2016, Landes and his collaborators found that nearly half of death certificates identify a developmental disability itself as the direct cause of death for individuals with disabilities

Progress in Closing the Age-at-Death Disparity for Adults with Intellectual and Developmental Disabilities

Intellectual and/or developmental disabilities (IDD) directly impact the course of an individual’s life, including the age at which they die