Reducing Imaging Utilization in Primary Care Through Implementation of a Peer Comparison Dashboard.

BACKGROUND: High clinical variation has been linked to decreased quality of care, increased costs, and decreased patient satisfaction. We present the implementation and analysis of a peer comparison intervention to reduce clinical variation within a large primary care network. OBJECTIVE: Evaluate existing variation in radiology ordering within a primary care network and determine whether peer comparison feedback reduces variation or changes practice patterns. DESIGN: Radiology ordering data was analyzed to evaluate baseline variation in imaging rates. A utilization dashboard was shared monthly with providers for a year, and imaging rates pre- and post-intervention were retrospectively analyzed. PARTICIPANTS: Providers within the primary care network spanning 1,358,644 outpatient encounters and 159 providers over a 3-year period. INTERVENTIONS: The inclusion of radiology utilization data as part of a provider's monthly quality and productivity dashboards. This information allows providers to compare their practice patterns with those of their colleagues. MAIN MEASURES: We measured provider imaging rates, stratified by modality, as well as order variation over time. KEY RESULTS: We observed significant variation in imaging rates among providers in the network, with the top decile ordering an average of 4.2 times more than the lowest decile in the two years prior to intervention. Provider experience and training were not significantly associated with imaging utilization. In the first year after sharing utilization data with providers, we saw a 17.3% decrease in median imaging rate (p < 0.001) and a 21.4% reduction in provider variation between top and bottom deciles. Median ordering rate for more costly cross-sectional imaging, including CT, MRI, and nuclear medicine studies, decreased by 30.4% (p < 0.001), 20.2% (p = 0.008), and 41.8% (p = 0.002), respectively. CONCLUSIONS: Peer comparison feedback can shape provider imaging behavior even in the absence of targets or financial incentives. Peer comparison is a low-touch, low-cost intervention for influencing provider ordering and may have applicability in other clinical areas.

Adsorption-induced scission of carbon-carbon bonds.

Covalent carbon-carbon bonds are hard to break. Their strength is evident in the hardness of diamonds and tensile strength of polymeric fibres; on the single-molecule level, it manifests itself in the need for forces of several nanonewtons to extend and mechanically rupture one bond. Such forces have been generated using extensional flow, ultrasonic irradiation, receding meniscus and by directly stretching a single molecule with nanoprobes. Here we show that simple adsorption of brush-like macromolecules with long side chains on a substrate can induce not only conformational deformations, but also spontaneous rupture of covalent bonds in the macromolecular backbone. We attribute this behaviour to the fact that the attractive interaction between the side chains and the substrate is maximized by the spreading of the side chains, which in turn induces tension along the polymer backbone. Provided the side-chain densities and substrate interaction are sufficiently high, the tension generated will be strong enough to rupture covalent carbon-carbon bonds. We expect similar adsorption-induced backbone scission to occur for all macromolecules with highly branched architectures, such as brushes and dendrimers. This behaviour needs to be considered when designing surface-targeted macromolecules of this type-either to avoid undesired degradation, or to ensure rupture at predetermined macromolecular sites.

Design and connection of robust genetic circuits.

Phenotypic robustness is a highly sought after goal for synthetic biology. There are many well-studied examples of robust systems in biology, and for the advancement of synthetic biology, particularly in performance-critical applications, fundamental understanding of how robustness is both achieved and maintained is very important. A synthetic circuit may fail to behave as expected for a multitude of reasons, and since many of these failures are difficult to predict a priori, a better understanding of a circuit's behavior as well as its possible failures are needed. In this chapter, we outline work that has been done in developing design principles for robust synthetic circuits, as well as sharing our experiences designing and constructing gene circuits.

Structure of long telomeric RNA transcripts: the G-rich RNA forms a compact repeating structure containing G-quartets.

Recent studies have identified RNA transcripts arising from mammalian telomeres with the transcript of the C-rich strand (r(5'-UUAGGG-3')(n)) being much more abundant than transcripts of the G-rich strand. Here we used transmission electron microscopy, CD, and nuclease digestion to investigate the structure of approximately 640-nucleotide (nt) RNA transcripts of the C-rich and G-rich strands of mammalian telomeric DNA. The CD spectrum of the C-rich RNA in low salt (10 mm KCl) or high salt (100 mm KCl) was typical of mixed sequence RNA, whereas the CD spectrum for the G-rich RNA differed with changes characteristic of parallel G-quadruplexes at the higher salt concentration. Electron microscopy visualization of the C-rich RNA revealed relatively extended unstructured molecules 59.7 +/- 17.8 nm in length and with a width consistent with single-stranded RNA following metal coating. In contrast, the G-rich RNA was observed as round particles and short, thick rods with the rods being most prevalent in high salt conditions and absent in low salt. The rods were 22.7 +/- 4.8 nm in length and 7.6 nm in width. Digestion of the G-rich RNA with T1 RNA nuclease revealed a ladder of bands whose sizes were integral multiples of 24 nt plus a 4-nt overhang. These observations suggest a model in which G-rich telomeric RNA folds into chains of particles each consisting of four (UUAGGG) repeats stabilized by parallel G-quartets and joined by UUA linkers. These chains further condense to form short rods and round particles.