A survey of stakeholders' perceived importance of health indicators and subgroup analyses to inform the Canadian clinical practice guideline for managing paediatric obesity

OBJECTIVE

To assess stakeholder ratings of health indicators and subgroup analyses in systematic reviews used to update the Canadian Clinical Practice Guideline for Managing Paediatric Obesity.

METHODS

Stakeholders (caregivers of children with obesity and Clinical Practice Guideline Steering Committee members) completed an online survey between April 2020 and March 2021. Participants rated importance of health indicators and subgroup analyses for behavioural and psychological, pharmacotherapeutic, and surgical interventions for managing paediatric obesity from not important to critically important using Grading, Recommendations, Assessment, Development and Evaluation criteria.

RESULTS

No health indicators or subgroup analyses were rated not important by the 30 caregivers and 17 Steering Committee members. Across intervention types, stakeholders rated anxiety, depression, health-related quality of life, serious adverse events, plus age and weight status subgroups as critically important.

CONCLUSION

Stakeholder ratings will inform data reporting and interpretation to update Canada's Clinical Practice Guideline for Managing Paediatric Obesity.

Updating the Canadian clinical practice guideline for managing pediatric obesity: a protocol

BACKGROUND

Since the first national guideline for managing obesity in adults and children in Canada was published in 2007, new evidence has emerged and guideline standards have evolved. Our purpose is to describe the protocol used to update the Canadian clinical practice guideline for managing pediatric obesity.

METHODS

This guideline will update the pediatric components of the 2007 Canadian clinical practice guideline for the management of obesity. In partnership with Obesity Canada, we began preliminary work in 2019; activities are scheduled for completion in 2022. The guideline will follow standards developed by the National Academy of Medicine and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) working group. Guideline development will be informed by 5 complementary literature reviews: a scoping review that focuses on clinical assessment in pediatric obesity management and 4 systematic reviews to synthesize evidence regarding families' values and preferences as well as the safety and effectiveness of interventions (psychological and behavioural; pharmacotherapeutic; and surgical). We will use standard systematic review methodology, including summarizing and assessing the certainty of evidence and determining the strength of recommendations. Competing interests will be managed proactively according to recommendations from the Guidelines International Network. Diverse stakeholders, including families and clinicians, will be engaged throughout guideline development.

INTERPRETATION

The guideline will support Canadian families and clinicians to make informed, value-sensitive and evidence-based clinical decisions related to managing pediatric obesity. The guideline and accompanying resources for end-users will be published in English and French, and we will partner with Obesity Canada to optimize dissemination using integrated and end-of-project knowledge translation.

Broadband reconfigurable logic gates in phonon waveguides

The high-quality-factor mechanical resonator in electromechanical systems has facilitated dynamic control of phonons via parametric nonlinear processes and paved the development of mechanical logic-elements. However, the narrow spectral bandwidth of the resonating element constrains the available nonlinear phenomena thus limiting the functionality of the device as well as the switching speeds. Here we have developed phonon waveguides, with a two-octave-wide phonon transmission band, in which mechanical four-wave-like mixing is demonstrated that enables the frequency of phonon waves to be converted over 1 MHz. We harness this platform to execute multiple binary mechanical logic gates in parallel, via frequency division multiplexing in this broadband, where each gate can be independently reconfigured. The fidelity of the binary gates is verified via temporal measurements yielding eye diagrams which confirm the availability of high speed logic operations. The phonon waveguide architecture thus offers the broadband functionality that is essential to realising mechanical signal processors.

Dispersive and dissipative coupling in a micromechanical resonator embedded with a nanomechanical resonator

A micromechanical resonator embedded with a nanomechanical resonator is developed whose dynamics can be captured by the coupled-Van der Pol-Duffing equations. Activating the nanomechanical resonator can dispersively shift the micromechanical resonance by more than 100 times its bandwidth and concurrently increase its energy dissipation rate to the point where it can even be deactivated. The coupled-Van der Pol-Duffing equations also suggest the possibility of self-oscillations. In the limit of strong excitation for the nanomechanical resonator, the dissipation in the micromechanical resonator can not only be reduced, resulting in a quality factor of >3× 10(6), it can even be eliminated entirely resulting in the micromechanical resonator spontaneously vibrating.

Phonon waveguides for electromechanical circuits

Nanoelectromechanical systems (NEMS), utilizing localized mechanical vibrations, have found application in sensors, signal processors and in the study of macroscopic quantum mechanics. The integration of multiple mechanical elements via electrical or optical means remains a challenge in the realization of NEMS circuits. Here, we develop a phonon waveguide using a one-dimensional array of suspended membranes that offers purely mechanical means to integrate isolated NEMS resonators. We demonstrate that the phonon waveguide can support and guide mechanical vibrations and that the periodic membrane arrangement also creates a phonon bandgap that enables control of the phonon propagation velocity. Furthermore, embedding a phonon cavity into the phonon waveguide allows mobile mechanical vibrations to be dynamically switched or transferred from the waveguide to the cavity, thereby illustrating the viability of waveguide-resonator coupling. These highly functional traits of the phonon waveguide architecture exhibit all the components necessary to permit the realization of all-phononic NEMS circuits.