Ruler Measurements Research Articles

The effect of different tensions/directions of I-shaped taping in combination with corrective exercise on postural kyphosis in adolescents.

Choosing appropriate complementary methods, such as exercise, along with taping methods may be effective in treating patients with kyphosis. The present study aimed to examine the effect of different tape tensions/directions combined with corrective exercises on the degree of postural kyphosis in adolescents. In this randomized controlled trial, 54 adolescents with postural kyphosis were assigned into three groups: No taping (control), I-shaped taping technique with 10% stretching force (Kinesiotape I), and I-shaped taping using facilitation technique with 40% stretching force (Kinesiotape II). Both groups in Kinesiotaping also received a V-shaped tape (10% stretching force). All participants received a similar comprehensive corrective exercise. Patients received the allocated interventions for 6 weeks and visited every two weeks at the clinic. Measurements were done using a flexible ruler, kyphometer, and photogrammetry. Between-group analyses revealed no significant differences between the study groups following the interventions (p> 0.05). However, the within-group analyses according to flexible ruler, Kyphometer, and Photogrammetry measurements indicated that exercise alone (control) [p= 0.011, p= 0.056, and p= 0.005, respectively], Kinesiotape I - exercise [p= 0.001, p= 0.002, p= 0.013, and respectively], as well as Kinesiotape II - exercise [p< 0.001, p< 0.001, and p< 0.001, respectively] significantly decreased the postural kyphosis degree except exercise alone using Kyphometer measurement. No adverse events were observed during the study. The findings of photogrammetry, flexible rulers, and photogrammetry similarly indicated that the corrective exercises with or without tape tension/directions significantly decreased the postural kyphosis degree in adolescents.

Overturning Children's Misconceptions about Ruler Measurement: The Power of Disconfirming Evidence.

Children have persistent difficulty with foundational measurement concepts, which may be linked to the instruction they receive. Here, we focus on testing various ways to support their understanding that rulers comprise spatial interval units. We examined whether evidence-based learning tools-disconfirming evidence and/or structural alignment-enhance their understanding of ruler units. Disconfirming evidence, in this context, involves having children count the spatial interval units under an object that is not aligned with the origin of a ruler. Structural alignment, in this context, involves highlighting what a ruler unit is by overlaying plastic unit chips on top of ruler units when an object is aligned with the origin of a ruler. In three experiments employing a pre-test/training/post-test design, a total of 120 second graders were randomly assigned to one of six training conditions (two training conditions per experiment). The training conditions included different evidence-based learning principles or "business-as-usual" instruction (control), with equal allocation to each (N = 20 for each condition). In each experiment, children who did not perform above chance level on the pre-test were selected to continue with training, which resulted in a total of 88 students for the analysis of improvement. The children showed significant improvement in training conditions that included disconfirming evidence, but not in the structural alignment or control conditions. However, an exploratory analysis suggests that improvement occurred more rapidly and was retained better when structural alignment was combined with disconfirming evidence compared to disconfirming evidence alone.

Design and Implementation of Precise Position Control for High-Power Stepper Motors and Grating Rulers Based on STM32

Abstract In common closed-loop feedback stepper systems, grating ruler displacement sensors are often used for linear displacement detection. To improve the precision positioning of the motor platform and meet the requirements of high-precision automated measurement, this paper proposes a high-power stepper motor 57J1880-450 based on STM32. The control system uses a grating ruler measurement platform to feedback displacement to the processor for displacement compensation, aiming to achieve high-precision closed-loop control of the linear motion platform. Experimental results have shown that the designed linear motion platform has a high-precision positioning function and can be applied to some motion positioning control systems.

Accuracy of digital measurement for quantitative and qualitative indicators of wound healing and repair: a systematic review protocol

IntroductionChronic wound care remains a critical public health challenge in terms of prevalence, quality of life and healthcare costs on a global scale. Currently used methods to assess the size...

PMCT-based sex determination using posterior segment of greater sciatic notch in North Indian population

BackgroundDigital tools, which offer superior accuracy compared to manual metrics, utilize radiological images for noninvasive data collection, providing a convenient means of obtaining skeletal data. The greater sciatic notch exhibits high sexual dimorphism and resistance to damage, and therefore serves as a viable tool for sex determination in poorly preserved skeletons, particularly in scenarios involving mass disasters, highly putrefied, and skeletonized cases. In addition to the width and depth of the greater sciatic notch, the length and angle of the posterior segment are highly specific parameters. This study aims to obtain accurate and standardized values for determining sex by measuring the posterior segment of the greater sciatic notch using postmortem computed tomography with a 16-slice multidetector row computed tomography scanner.ResultsThe study revealed that except for depth and the distance between the ischial spine and deepest point, all measured variables of the greater sciatic notch were greater for women than men on both sides. The length of the posterior segment and the posterior angle on both sides showed the highest positive correlation and provided highly significant differences between males and females. These findings not only reinforce the utility of the greater sciatic notch in sex determination but also highlight the potential for more accurate and noninvasive methods in forensic investigations.ConclusionsPostmortem computed tomography accurately determines sex by measuring the posterior sciatic notch segment, achieving a 90.9% accuracy rate. This study, the first of its kind in India, utilized postmortem computed tomography ruler measurements for sex determination, specifically evaluating the role of the posterior segment dimensions of the greater sciatic notch in the North Indian population.

Effect of NFX-179 MEK inhibitor on cutaneous neurofibromas in persons with neurofibromatosis type 1.

This phase 2a trial investigated the efficacy of NFX-179 Topical Gel, a metabolically labile MEK inhibitor, in the treatment of cutaneous neurofibromas (cNFs) in neurofibromatosis type 1. Forty-eight participants were randomized to four treatment arms: NFX-179 Topical Gel 0.05%, 0.15%, and 0.5% or vehicle applied once daily to five target cNFs for 28 days. Treatment with NFX-179 Topical Gel resulted in a dose-dependent reduction in p-ERK levels in cNFs at day 28, with a 47% decrease in the 0.5% NFX-179 group compared to the vehicle (P = 0.0001). No local or systemic toxicities were observed during the treatment period, and systemic concentrations of NFX-179 remained below 1 ng/ml. In addition, 20% of cNFs treated with 0.5% NFX-179 Topical Gel showed a ≥50% reduction in volume compared to 6% in the vehicle group by ruler measurement with calculated volume (P = 0.021). Thus, NFX-179 Topical Gel demonstrated significant inhibition of MEK in cNF with excellent safety and potential therapeutic benefit.

Real-Time Measurement and Uncertainty Evaluation of Optical Path Difference in Fiber Optic Interferometer Based on Auxiliary Interferometer.

Optical interferometers are the main elements of interferometric sensing and measurement systems. Measuring their optical path difference (OPD) in real time and evaluating the measurement uncertainty are key to optimizing system noise and ensuring system consistency. With the continuous sinusoidal wavelength modulation of the laser, real-time OPD measurement of the main interferometer is achieved through phase comparison of the main and auxiliary interferometers. The measurement uncertainty of the main interferometer OPD is evaluated. It is the first evaluation of the impact of different auxiliary interferometer calibration methods on OPD measurements. A homodyne quadrature laser interferometer (HQLI) is used as the main interferometer, and a 3 × 3 interferometer is used as the auxiliary interferometer. The calibration of the auxiliary interferometer using optical spectrum analyzer scanning and ruler measurement is compared. The evaluation shows that the auxiliary interferometer is the most significant source of uncertainty and causes the total uncertainty to increase linearly with increasing OPD. It is proven that a high-precision calibration and large-OPD auxiliary interferometer can improve the real-time accuracy of OPD measurements based on the auxiliary interferometer. The scheme can determine the minimum uncertainty to optimize the system noise and consistency for vibration, hydroacoustic, and magnetic field measurements with OPDs of the ~m level.

Pubertal testicular volume references for ruler, orchidometer, and ultrasonography measurements based on a longitudinal follow-up.

Testicular volume is a marker of male pubertal development. Various clinical conditions and their treatments may influence testicular growth. To create ruler-based age-dependent pubertal testicular volume references that enable calculation of standard deviation (SD) scores. Study cohort comprised 65 boys who attended clinical examination twice a year from the age of 8.5 years until the attainment of final testicular size. Forty-nine (75.4%) boys completed the follow-up and 16 (24.6%) boys dropped out before the attainment of final post-pubertal testicular size. At each follow-up visit testicular size was measured with a ruler, orchidometer, and ultrasonography. LMS or LMSP method served as the technique for creating reference growth curves for testicular volumes. Using the novel references for ruler measurements, development of SD scores was assessed in a cohort of boys with unilateral cryptorchidism. Reference growth curves were constructed separately for ruler, orchidometer, and ultrasonography measurements. Median orchidometer volume of 4mL, marker of male pubertal onset, occurred at the age of 11.7 years, whereas +2SD curve surpassed 4mL at 10.2 years and -2SD curve at 13.7 years. Modeled ages at the attainment of 4mL testicular volume based on ruler measurements were 9.7 years for +2SD curve, 11.5 years for median curve, and 13.6 years for -2SD curve. Ultrasonography-based volume of 1.3mL corresponded with the median modeled orchidometer-based volume of 4mL. In boys with unilateral cryptorchidism, ruler-based SD scores decreased during puberty in undescended testes, but not in descended testes. The present study provides reference values for pubertal testicular volume measured with a ruler enabling an age-dependent assessment of testicular size. Comparison with measurements by an orchidometer and ultrasonography is also presented.

Can Weight Bearing Aerobic Exercise be Done Safely with an Active Diabetic Plantar Foot Ulcer and Can It Improve Healing Time

Introduction Diabetic foot ulcer (DFU) is a huge economic burden on the National Health Service (NHS). Research on the benefits of aerobic exercise on the vascular system in diabetics is vast, however research on the benefits of aerobic exercise on diabetics with active plantar DFU is slim. The purpose of this review is to determine whether weight bearing aerobic exercise can be safely undertaken with an active plantar DFU and whether exercise can in fact improve ulcer healing time. Method Five papers that included patients with active DFU taking part in weight bearing or semi weight bearing aerobic exercise programmes &gt;10-weeks were found and reviewed. Findings Non-weight-bearing or semi-weight bearing exercise in the presence of DFU alongside severe diabetic neuropathy (DN) is safer and more feasible in the aim to try and stop the regression of diabetic complications. It has not been concluded whether aerobic exercise improves ulcer healing time. Proposal A pre-test, post-test randomized controlled trial (RCT), 30 participants (15 male, 15 female) with type 2 diabetics (T2D) and active plantar DFU, recruited from the Peter Mount Diabetes and Endocrine clinic at the Manchester Royal Infirmary, randomized into an evenly split intervention group/control group. Intervention group will take part in fully supervised 12-week semi weight bearing aerobic/resistance-based exercise programme: 3×per week working at 40-60% heart rate reserve (HRR) (Karvonen method) at the rehabilitation gym, Manchester Royal Infirmary (MRI). Participants will wear a removable air cast walker or equivalent. Monthly motivational interviewing and bi-weekly foot checks will be undertaken. Control group will continue usual wound care plan from the diabetic clinic. Outcome Measures: Baseline, 6, 12-weeks: transparent ruler measurement, toe brachial pressure index (TBPI) toe pressures, SPO2 , ankle brachial index (ABI), fasting blood glucose (FBG), blood cholesterol levels, Semmes monofilament test, blood pressure (BP), body mass index (BMI). Statistically analysed by statistical package for social sciences (SPSS) version 28 at p&lt;0.05.

Design an IoT Based Pratima Monitoring System

Pratima is usually kept in temples or kept in sacred rooms. Lack of care and supervision causes easy cases of theft and damage due to fire. An Internet of Things-based pratima monitoring system is needed to avoid some of the threats that occur. Devices that are made connected to the internet for monitoring, and controlling monitoring devices so that Pratima remains safe. The Internet of Things-based pratima monitoring system is expected to be an early prevention system for acts of theft and damage due to fire. The results obtained are all the features successfully run. The measurement values of the ultrasonic sensor are 11CM and 16CM, while the ruler measurements are 10.5CM and 16CM. The temperature on the DHT22 is 70.50°C, and the flame sensor value is 123. The microwave sensor detects movement, and the image capture is stored on firebase and SD Card.

The current position of wound imaging in the UK.

British Journal of NursingVol. 32, No. 12 CommentThe current position of wound imaging in the UKSteven LA JefferySteven LA JefferyE-mail Address: [email protected]Consultant Burns and Plastic Surgeon, Professor of Wound Study, Birmingham City University and Medical Director, Pioneer Wound TelehealthSearch for more papers by this authorSteven LA JefferyPublished Online:21 Jun 2023https://doi.org/10.12968/bjon.2023.32.12.S4AboutSectionsView articleView Full TextPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareShare onFacebookTwitterLinked InEmail View article References Guest JF, Fuller GW, Vowden P. Cohort study evaluating the burden of wounds to the UK's National Health Service in 2017/2018: update from 2012/2013. BMJ Open. 2020;10(12):e045253. https://doi.org/10.1136/bmjopen-2020-045253 Crossref, Medline, Google ScholarRoyal College of Nursing. Valuing nursing in the UK. Staffing for safe and effective care in the UK: interventions to mitigate risks to nursing retention. 2019. https://tinyurl.com/5n7ytp7r (accessed 14 June 2023) Google ScholarRogers LC, Bevilacqua NJ, Armstrong DG, Andros G. Digital planimetry results in more accurate wound measurements: a comparison to standard ruler measurements. J Diabetes Sci Technol. 2010;4(4):799-802. https://doi.org/10.1177/193229681000400405 Crossref, Medline, Google ScholarSavage JM, Jeffery SL. Use of 3D photography in complex-wound assessment. J Wound Care. 2013;22(3):156-160. https://doi.org/10.12968/jowc.2013.22.3.156 Link, Google ScholarWynn M, Scholes L. Trial of the Minuteful mobile application for wound care in an inpatient setting. Wounds UK. 2022;18(4):37–40 Google Scholar FiguresReferencesRelatedDetails 22 June 2023Volume 32Issue 12ISSN (print): 0966-0461ISSN (online): 2052-2819 Metrics History Published online 21 June 2023 Published in print 22 June 2023 Information© MA Healthcare LimitedPDF download

What is the angle of a banana? The difficulty in reliable assessment of hypospadias chordee

The degree of chordee associated with hypospadias impacts operative management. Unfortunately, poor inter-observer reliability in assessing chordee by multiple methods invitro has been demonstrated. This variability may be related to the fact that chordee is not a discrete angle, but rather an arc-like curvature similar to that of a banana. On an attempt to improve this variability, we assessed the inter-rater reliability of a novel method of chordee measurement and compared it to measurements with a goniometer both invitro and invivo. Invitro assessment of curvature was performed using 5 bananas. Invivo chordee measurement was performed during 43 hypospadias repairs. On invitro and invivo cases, chordee was assessed independently by faculty and resident physicians. Angle assessment was performed in a standard manner with a goniometer and with a smartphone app using ruler measurements of the length and width of the arc (Summary Figure). The proximal and distal aspect of the arc to be measured was marked on the bananas, whereas the penile measurements were taken from the penoscrotal to the sub-coronal junctions. Invitro banana assessment demonstrated strong intra- and inter-rater reliability for length (0.89 and 0.88, respectively) and width measurements (0.97 and 0.96). The calculated angle demonstrated an intra- and inter-rater reliability of 0.67 and 0.67. The banana goniometer/protractor measurements were weak with an intra-rater and inter-rater reliability of 0.33 and 0.21. With hypospadias chordee, the inter-rater reliability was strong for length and width measurements (0.95 and 0.94) and 0.48 for calculated angle. The inter-rater reliability of the goniometer angle was 0.96. Further assessment of inter-rater goniometer reliability was performed relative to degree of chordee as characterized by faculty. The inter-rater reliability for ≤15°, 16-30, and ≥30° was 0.68 (n=20), 0.34 (n=14), and 0.90 (n=9), respectively. When the goniometer angle was classified as ≤15, 16-30, or ≥30° by one physician, it was classified outside of this range by the other physician 23%, 47%, and 25% of the time, respectively. Our data demonstrate significant limitations of the goniometer for assessing chordee invitro and invivo. We were unable to demonstrate significant improvement in chordee assessment using arc length and width measurements to calculate radians. Reliable and precise techniques for measuring hypospadias chordee remain elusive and draw into question the validity and usability of management algorithms employing discrete values.

New opportunities for low-cost LiDAR-derived snow depth estimates from a consumer drone-mounted smartphone

Snow has significant impacts on springtime flooding, water resource management practices and the regional water-energy budget. In situ observations are considered some of the highest quality measurements of snow depth available, and are useful constraints for numerical weather prediction models and reanalysis system estimates of snow water equivalent. The application of laser altimetry (LiDAR-Light Detection and Ranging) for measuring snow depth has proven an effective method for quickly observing large areas, however this technique is expensive to perform due to the high cost of the necessary equipment coupled with required operator training. In this work, we examine the capabilities of the iPhone 12 Pro LiDAR (iLiDAR) when attached to a consumer-grade DJI Phantom 4 quadcopter in estimating snow depth at three study sites in southern Ontario, Canada. Initial comparisons between drone iLiDAR depth estimates and collocated snow ruler measurements demonstrate good agreement, with a root-mean-square error of 3 cm and absolute mean error of 2.5 cm. The intersection of these two technologies defines a novel, low-cost alternative to traditional LiDAR-based snow depth measurement systems, while maintaining a high level of observational accuracy and precision.

Data Alignment Design for Robotic Programming by Demonstration Based on IMU and Optical Tracker

This study proposes a data alignment design for sensor fusion of an optical target (OT) and an inertial measurement unit (IMU) to track the trajectory of a handheld tool for robot programming by demonstration (PbD). A novel method is proposed for coordinate and temporal alignment between the OT and the IMU sensor to increase the tracking accuracy. The IMU measurements are aligned with the corresponding angular velocities and accelerations derived from the OT to calibrate the IMU-OT relationship. Global and local optimizations are combined to reduce the computation time for the temporal alignment and coordinate calibration. Experimental results show that the proposed method provides improved calibration results with shorter calculation time compared with two existent methods. The sensor fusion experiments verify the accuracy of trajectory tracking of 1.3mm using the calibration result, an improvement from 1.4mm of the data alignment using ruler measurement. Integrated PbD experiments by using a 6-DOF manipulator were carried out to evaluate the proposed method. The manipulator imitated the hand motion of a bottle transfer task with the trajectory error of 0.66mm. Practical robotic experiments demonstrate that the method is suitable for robot programming applications.

Extraction of Ruler Markings For Estimating Physical Size of Oral Lesions.

Small ruler tapes are commonly placed on the surface of the human body as a simple and efficient reference for capturing on images the physical size of a lesion. In this paper, we describe our proposed approach for automatically extracting the measurement information from a ruler in oral cavity images which are taken during oral cancer screening and follow up. The images were taken during a study that aims to investigate the natural history of histologically defined oral cancer precursor lesions and identify epidemiologic factors and molecular markers associated with disease progression. Compared to similar work in the literature proposed for other applications where images are captured with greater consistency and in more controlled situations, we address additional challenges that our application faces in real world use and with analysis of retrospectively collected data. Our approach considers several conditions with respect to ruler style, ruler visibility completeness, and image quality. Further, we provide multiple ways of extracting ruler markings and measurement calculation based on specific conditions. We evaluated the proposed method on two datasets obtained from different sources and examined cross-dataset performance.

Evaluation of LiDAR-Derived Snow Depth Estimates From the iPhone 12 Pro

Snow is a critical contributor to the global water-energy budget with impacts on springtime flooding and water resource management practices. Laser altimetry [light detection and ranging (LiDAR)] is a remote-sensing technique that has demonstrated skill in monitoring snow depth, but the expense of purchasing and transporting traditional LiDAR equipment limits their operational use. In this work, we demonstrate that the LiDAR sensor installed on the Apple iPhone 12 Pro consumer smartphone is a real-time, handheld measurement instrument for accurately observing changes in snow depth. Two independent field experiments in Southern Ontario, Canada, found that the iPhone LiDAR was able to accurately capture daily changes in snow depth when compared to <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in situ</i> snow ruler measurements. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">In situ</i> and LiDAR comparisons of xs <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$n=75$ </tex-math></inline-formula> days at measurement site A exhibit a correlation of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$r &gt; 0.99$ </tex-math></inline-formula> , mean absolute bias less than 1 mm, and a root mean squared error (RMSE) of approximately 6 mm. A similar positive agreement was also noted at the second field study site for <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$n=16$ </tex-math></inline-formula> measurements over the same period. The high accuracy of the LiDAR sensor suggests that a mobile application could be developed which allows users to quickly scan a snow-covered area before and after a snowfall event and consequently use this data to aid in filling current observational gaps through a citizen-science-based approach to measuring changes in snow depth.

A novel use of 3D-printed template in vaginal HDR brachytherapy

PURPOSEThe High-Dose-Rate (HDR) vaginal cylinder treatment is typically designed using the initial CT, while the subsequent implants are verified using rudimentary methods (i.e., visual inspection, ruler measurements, etc.) and/or X-ray imaging. We are proposing the use of a 3D-printed individualized template that could provide simple and reproducible vaginal cylinder insertion. MATERIAL AND METHODSSix patients were included in the study with prescriptions of 6 Gy/fraction for 2 to 5 fractions (total 27 treatments). The first 1 to 2 treatments were delivered without the template and the rest with the CT-based 3D-printed templates. Cone beam CTs (CBCTs) were acquired to verify the cylinder placement for all treatments. D2cc of the bladder and rectum are recorded on both planning CT and the following on-treatment CBCTs. RESULTSBy using the templates, the tip position variation on average (±1 SD) reduced from 0.8±0.5 cm to 0.6±0.4 cm, and angular difference decreased from 5.3±3.5° to 4.7±2.4°. The pitch and yaw deviation are reduced from 0.9 ± 5.8° and 0.4±2.9° to 0.0±3.9° and -0.2±3.0°, respectively. The deviation of D2cc to bladder from the plan reduced from 6±4% to 5±3%, and rectum from 5±2% to 4±4%. CONCLUSIONThe 3D-printed patient-specific cylinder templates could potentially improve the geometrical reproducibility of cylinder treatments at no cost of additional imaging. The D2cc for the bladder and rectum are determined by the treatment length rather than their respective volumes.

The Precision of Ophthalmic Calipers: A Potential Reason for Clinical and Surgical Errors.

PurposeThe study aimed to determine the precision of different ophthalmic calipers used in our tertiary eye care center.MethodsAll Castroviejo calipers available in the operating room, minor treatment room, and intravitreal injection clinic were included in the study. All calipers were evaluated at four screening points (1, 5, 10, and 15 mm) on a standard ruler and compared to their expected corresponding readings on the caliper scale. If any caliper showed a discrepancy of ≥0.5 mm at any of the screening points, the caliper underwent further analysis on 10 measurement points.ResultsForty-one calipers were evaluated, of which 16 (39%) showed at least one point of ≥0.5 mm discrepancy on the caliper reading scale. Six calipers had errors >0.5 mm and two calipers had measurement errors of 1 mm in at least one point between 1-15-mm ruler measurement points. The majority of calipers (15/16) overestimated lengths.ConclusionCalipers are prone to damage with prolonged use that may affect their precision. Thus, calipers should be calibrated against a standard ruler prior to use even if they look grossly intact. Regular screening of calipers is recommended to identify any discrepancy and prevent avoidable complications.

Constraints on power law cosmology from cosmic chronometer, standard ruler, and standard candle data

In this paper I investigate how well simple power law expansion fits observational data in comparison to the standard ΛCDM model. I analyze a data set consisting of cosmic chronometer, standard ruler, and standard candle measurements, finding that the ΛCDM model provides a better fit to most combinations of these data than the power law ansatz.

Canadian In Situ Snow Cover Trends for 1955–2017 Including an Assessment of the Impact of Automation

ABSTRACT Snow cover trends for Canada over the 1955–2017 period for the daily snow depth–observing network of Environment and Climate Change Canada (ECCC) are presented based on an updated quality-controlled historical daily in situ snow depth dataset. The period since approximately 1995 is characterized by a rapid decline in manual observations (loss of over 800 manual observing sites between 1995 and 2017) and an increasing number of automated stations equipped with sonic snow depth sensors. In 2017 these accounted for approximately 45% of the network and more than 80% of the snow depth–observing network north of latitude 55°N. Automated stations are characterized by more frequent missing and anomalous data than manual ruler observations, particularly at Arctic sites. A comparison of closely located automated sonic and manual ruler observations showed similar numbers of days with snow cover but the sonic sensors detected significantly lower snow depths. For time series analysis of annual snow cover variables, the systematic difference between ruler and sonic snow depth can be removed using a common 2003–2016 reference period to compute snow cover anomalies. The updated trend results are broadly similar to previously published assessments showing long-term decreases in annual snow cover duration (SCD) and snow depth over most of Canada, with the largest decreases observed in spring snow cover and seasonal maximum snow depth (SDmax). Significant declines in SCD and SDmax of −1.7 (±1.1) days decade-1 and −1.8 cm (±0.8) cm decade−1 were observed in the Canada–averaged series over the 1955–2017 period. These trends mainly reflect snow cover conditions over southern Canada where the observing network is concentrated and where there are significant negative correlations between snow cover and winter air temperature. Declining numbers of stations reporting snow depth, issues with sonic sensor data quality, and systematic differences between ruler and sonic sensor measurements are major challenges for continued climate monitoring with the current ECCC snow depth–observing network.