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2931 citation(s) found for "Ryan, M".

D24-15 Custom Y-stent Utilization in a Unique Tracheobronchomalacia Patient
Conrad, P, Jaimes, G Ortiz, Kern, R, ORTIZ-JAIMES, GABRIEL E, Kern, Ryan

American Journal of Respiratory and Critical Care Medicine | May 18, 2026 | Volume: 212 | Issue: Supplement_1 | Pages: No page available

10.1093/ajrccm/aamag162.3595 Get It

Abstract Introduction Custom stents are a fast-evolving and revolutionary therapy for use in patients who require therapeutic stenting options due to a variety of tracheal, bronchial, and parenchymal diseases. The combination of increasing high-resolution CT imaging with 3-D printing technology has allowed for even greater flexibility in therapeutic treatment. Returned mesh is a well-described phenomenon in the medical literature and can create a wide variety of difficult to manage complications. Description The patient is a 64-year-old male with a past medical history of tracheobronchomalacia status post tracheoplasty with prolene mesh placement in April 2011 which was complicated by erosion of mesh through the membranous airway in April 2017. He subsequently underwent a right thoracotomy with a muscle flap reconstruction of the membranous trachea in May 2017. This was then complicated by a diverticulum of the distal trachea that was non-communicative with the esophagus and chronic stenosis of the left mainstem bronchus with residual mesh retained in the posterior membranous left mainstem bronchus. He had a custom Y-stent placed for the first time in February 2022 due to persistent sensation of shortness of breath along with productive cough. He experienced immediate relief after placement of his custom stent and has since demonstrated remarkable stability, rarely requiring unscheduled bronchoscopy for mucous clearance. He has nonetheless derived immense benefit from stenting from a symptomatic standpoint since initial placement in 2022. Discussion Customized stents utilizing 3-D printing technology have allowed far more flexibility to the clinical approach of patients with complex airway pathology. As tracheal and bronchial reconstruction surgeries continue to involve more complicated management modalities, including the use of mesh, complications will continue to arise. Mesh erosion is a potentially devastating complication from tracheobronchoplasty. It will, therefore, be important to facilitate treatment of complications from these and other modalities. Therapeutic bronchoscopy with custom stent placement will almost certainly continue to evolve as an effective tool in the management of patients such as these. This abstract is funded by: None
C79-04 NUT Carcinoma-induced Central Airway Obstruction Treated With Pulsed Electric Field Ablation
Bugayong, M, Ortiz-Jaimes, G E, Edell, E S, Kern, R M, Garcia, S I, Bugayong, Maria Lorraine , ORTIZ-JAIMES, GABRIEL E, Edell, Eric S. , Kern, Ryan

American Journal of Respiratory and Critical Care Medicine | May 18, 2026 | Volume: 212 | Issue: Supplement_1 | Pages: No page available

10.1093/ajrccm/aamag162.3561 Get It

Abstract Introduction Nuclear protein in testis (NUT) carcinoma, formerly known as NUT midline carcinoma, is a rare and highly aggressive subtype of squamous cell carcinoma characterized by NUTM1 gene rearrangements. It typically affects children and young adults and shows a predilection for midline structures of the head, neck, and thorax. We describe a rare case of NUT carcinoma in an elderly patient presenting with central airway obstruction treated with tumor debulking, devascularization, and pulsed electric field (PEF) ablation. Case An 89-year-old woman on chronic anticoagulation for atrial fibrillation presented with respiratory distress and hemoptysis requiring intubation and mechanical ventilation. Chest CT revealed a developing right lower lobe infiltrate and bronchoscopy demonstrated a non-obstructing right lower lobe endobronchial lesion. Pathology of the lesion confirmed NUT carcinoma but the patient was lost to follow-up. Two months later, she presented with altered mental status and respiratory failure. Imaging revealed a 4.6 x 2.6 cm mass at the level of the cricoid cartilage causing approximately 75% tracheal obstruction with tracheal wall invasion. She underwent rigid bronchoscopy with tumor debulking and devascularization, achieving >80% tracheal patency post-procedure. EBUS-guided PEF ablation was then performed to target residual bulky tumor found in the paratracheal area. Given her age, comorbidities, and poor performance status, palliative chemotherapy was deferred and palliative radiotherapy was offered to limit tumor progression. Discussion NUT carcinoma is a rare and aggressive malignancy with a poor prognosis. This case demonstrates rapid tumor progression leading to respiratory failure within two months of initial diagnosis. Management options for malignant central airway obstruction in non-surgical candidates may include endobronchial debulking and ablative therapies. In this case, EBUS-guided PEF ablation, a non-thermal technique that delivers brief electric pulses to induce tumor apoptosis while sparing adjacent structures, was successfully used to treat residual disease with the goal of reducing marginal regrowth and maintain airway patency. PEF ablation has been described in percutaneous and bronchoscopic management of early stage non-small cell lung cancer; however, its application in central airway obstruction represents an innovative therapeutic approach. Although chemoradiation may be considered when feasible, no standard regimen exists for NUT carcinoma. It typically responds poorly to conventional therapies, underscoring the importance of complementary local treatment strategies in select patients. This case highlights the rapidly progressive course of NUT carcinoma and demonstrates the potential role of PEF ablation as a novel adjunct in the palliative management of malignant central airway obstruction. This abstract is funded by: None
Development of a Large Animal Rectovaginal Fistula Model
Westenberg, Danielle N., Sarrafian, Tiffany L. , Mahlberg, Ryan, Stalboerger, Paul G., Trabuco, Emanuel C. , Dozois, Eric J. , Occhino, John A. , Westenberg, Danielle, Mahlberg, Ryan , Behfar, Atta

Urogynecology | May 18, 2026 | Volume: 32 | Issue: 6 | Pages: 646-651

10.1097/spv.0000000000001706 | PMID 42149670 Get It

Importance Rectovaginal fistulas (RVFs) are challenging to treat, often requiring multiple surgical interventions. Research into novel therapies is limited by the lack of a sizeable and representative animal model. Given the similarities in porcine and human vaginal and rectal tissue, pigs are an ideal species for translation to human patients. Objective The objective of this study was to develop a feasible and reproducible RVF model in pigs. Study Design Six female pigs underwent RVF creation and were divided into 3 groups according to the following methods: (1) placement of 1-inch disc magnets across the rectovaginal septum, (2) a 1-inch round defect created using electrocautery and placement of a 1-inch stainless-steel gauge stent, (3) a 1-inch round defect using electrocautery without subsequent stenting. Fistulas were evaluated at 6 weeks with measurements and photographic documentation. The animals were euthanized between 12 and 14 weeks. The primary outcome of this study was fistula patency. Secondary outcomes were fistula dimension and histologic appearance of the fistula tract. Results All pigs did well with no infection or complications related to fistula creation. Both surgical methods reliably resulted in a patent fistula at 14 weeks: cautery alone and cautery with gauge stenting. Only 1 patent fistula in the magnet group was noted at the time of euthanasia. All patent fistulas showed histologic evidence of complete epithelialization of the fistula tract. Conclusions This study demonstrates 3 safe and feasible methods for RVF creation in pigs, with 2 methods showing increased reliability.
Fast 3-D Ultrasound Localization Microscopy via Projection-Based Processing Framework
Zhang, Jingke , Yin, Jingyi , Huang, Lijie , DeRuiter, Ryan M. , Ji, Kaipeng , Zhao, Yanzhe , Krier, James D., Zhu, Xiang, Lerman, Lilach O. , Yin, Jingyi , Zhang, Jingke , DeRuiter, Ryan , Lok, U‐Wai , Wu, Tao , Ji, Kaipeng, Huang, Chengwu , Chen, Shigao

IEEE Transactions on Medical Imaging | May 15, 2026 | Volume: 45 | Issue: 7 | Pages: 4105-4122

10.1109/tmi.2026.3692792 | PMID 42139135 Get It

Human Spastic Muscle Remodels After Surgical Hyper-Selective Neurectomy
Wang, Zheng, Pichika, Rajeswari , Rhee, Peter, Kaufman, Kenton, Lieber, Richard, Rhee, Peter C , Kaufman, Kenton R. , Lieber, Richard L.

Physiology | May 12, 2026 | Volume: 41 | Issue: S1 | Pages: No page available

10.1152/physiol.2026.41.s1.2289722 Get It

Background: Spasticity after upper motor neuron injury (stroke, spinal cord injury, etc.) alters muscle activity and induces long-term structural remodeling of skeletal muscle [1]. Elbow flexors, including the biceps brachii, are frequently affected, leading to abnormal tone, involuntary co-contraction, and impaired elbow function. Hyper-selective neurectomy (HSN) is a well-established surgical technique that has gained renewed clinical adoption with advances in anatomic understanding and intraoperative nerve mapping [2], yet its effects on muscle properties are poorly defined. Objective: The purpose of this study was to define pre- vs. post-HSN differences in muscle gene expression, sarcomere length, and clinical outcomes of the spastic human biceps. Methods: Individuals with elbow flexor spasticity undergoing a planned two-stage HSN were prospectively enrolled (n=10). Stage 1 released the elbow flexors and provided a pre-biopsy; Stage 2, performed ~3 months later to treat the forearm flexors, provided a second exposure to the biceps and a second biopsy. In both stages, biceps biopsies were obtained with customized clamps [3] at predefined elbow angles (50°, 90°, 135°), fixed, and analyzed for sarcomere length [4]. Total RNA was extracted from pre- and post-HSN biceps samples to characterize transcriptional changes. Clinical spasticity was assessed before Stage 1 and again before Stage 2 using the Modified Ashworth Scale (MAS). Data were compared using repeated-measures models, and single-cell transcriptional changes were analyzed using established analytical pipelines. Results: Sarcomere length (SL) increased significantly after HSN at all joint angles. At 50°, SL increased from 2.45 ± 0.18 µm pre-HSN to 3.05 ± 0.28 µm post-HSN; at 90°, from 2.70 ± 0.29 µm to 2.91 ± 0.16 µm; and at 135°, from 2.72 ± 0.36 µm to 3.24 ± 0.32 µm (all p < 0.05). Clinical spasticity assessment improved significantly as well (p < 0.05), with MAS scores decreasing from 1.89± 0.93 to 0.35 ± 0.53. RNA sequencing revealed changes in key pathways and overall gene expression patterns such as enhanced inflammatory response through increased cytokine production and fibroblast proliferation, leading to elevated collagen synthesis and subsequent fibrosis. We also observed upregulated immune modulation and chemotaxis, while pathways involved in mitochondrial respiration, muscle development, and cellular homeostasis were downregulated. At the transcript level, HSN led to decreased inflammation and adipogenesis, while promoting increased extracellular matrix assembly, and vascular formation. Conclusion: HSN produced coordinated improvements across structural, clinical, and transcriptional levels in the spastic human biceps muscle. Sarcomere lengths increased toward longer resting lengths at all joint angles, clinical spasticity decreased significantly, and RNA sequencing revealed distinct post-operative transcriptional remodeling. The longer sarcomere length and decreased spasticity should contribute to improved patient function after HSN. References: 1. Lieber RL et al. Muscle Nerve. 2002;26:98–105. 2. Leclercq C et al. Hand Clin. 2018;34:537–545. 3. Lieber RL et al. J Neurophysiol. 1994;71:874–881. 4. Ward SR et al. J Biomech. 2009;42:193–196. This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.
First in human evidence of autonomically-mediated immune dysfunction after spinal cord injury
Solinsky, Ryan, Hareland, Kimberly, Veith, Daniel, Overlee, Brittany, Shang, Pei , Clarkson, Ben, Howe, Charles, Solinsky, Ryan , Veith, Daniel D. , Overlee, Brittany L., Howe, Charles L.

Physiology | May 12, 2026 | Volume: 41 | Issue: S1 | Pages: No page available

10.1152/physiol.2026.41.s1.2345659 Get It

Study objective: To characterize physiologic autonomic dysfunction in humans after chronic spinal cord injury (SCI) relative to uninjured controls and to identify autonomic correlates to neuroimmune deficits. Hypothesis: Individuals with greater autonomic dysfunction after SCI will have more pronounced immune dysfunction, which will be further influenced by sympathetically mediated increases in catecholamine levels. Methodology: Both uninjured controls and individuals with SCI completed a battery of autonomic physiology tests aimed at characterizing preservation of supralesional/sublesional sympathetic activation and global sympathetic inhibition. The autonomic testing battery included 3-minute hand and foot cold pressor tests, 3 Valsalva maneuvers with goal expiratory pressure of 30 mmHg, a novel bladder pressor test (5 minutes of sustained bladder pressure at 35 cmH20 with room temperature sterile water infusion), paced breathing at 0.25 Hz for heart rate/blood pressure variability, and successive doses of bolus intravenous phenylephrine (Oxford technique). A subset of individuals in both cohorts had baseline and cold pressor stressed levels of catecholamines/cortisol drawn and immunologic assessments. Peripheral blood mononuclear cells were extracted from this baseline sample and assessed with flow cytometry for cellular exhaustion markers (CD69, PD-1, TIGIT, TIM-3). Antigen recall response, with/without primed exposure of catecholamines was also completed to identify how sympathetic activation variably impacted functional immune performance with exposure to viral peptides. Data: n=35 uninjured controls; n=29 individuals with SCI Summary of Results: When compared to uninjured controls, individuals with SCI demonstrated significant autonomic dysfunction in all three domains, with decreased supralesional sympathetic activation (Valsalva pressure recovery time, p< 0.0001), abnormal sublesional sympathetic activation (increased bradycardia, p< 0.0001), and impaired sympathetic inhibition (larger dose/body-weight adjusted increase in mean arterial pressure, p=0.0006). As expected, autonomic dysfunction in those with SCI existed on a continuum, with some having largely normal autonomic regulation and others exhibiting profound deficits. Principal component analysis confirmed these three domains as the primary drivers of variability. Cellular exhaustion markers were increased in those with SCI, with positive correlation (R2=0.42) between degree of global autonomic dysfunction (Z-score over 2.0) and CD3+ CD8+ T-cell TIM-3 immunologic exhaustion markers. Antigen recall response was impaired in those with SCI and autonomic dysfunction on physiologic testing, with pronounced decrement in response when catecholamines were added (mean 57% of response lost in CD69 T-cells to Epstein-Barr virus antigen exposure, 53% lost to Flu antigen). Conclusions: In humans with SCI, early evidence supports that individuals have greater autonomic dysfunction and that this is correlated to increased immunologic deficits. Funding Sources: NIH K23HD102663, R01NS115126 This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.
Virulence factors released by Staphylococcus aureus induce oxidative stress which stimulates ATP release, Ca 2+ mobilization and IL-33 secretion in human airway epithelial cells
Srisomboon, Yotesawee, Hunter, Ryan, Kita, Hirohito, O'Grady, Scott, Hunter, Ryan C. , Kita, Hirohito

Physiology | May 12, 2026 | Volume: 41 | Issue: S1 | Pages: No page available

10.1152/physiol.2026.41.s1.2294883 Get It

Staphylococcus aureus is a well-known pathogen responsible for a wide range of diseases with life-threatening consequences. Its public health burden continues to be significant due to pervasive colonization and growing antimicrobial-resistance (i.e., methicillin-resistant S. aureus, MRSA). In the present study we found that exposure of human bronchial epithelial (hBE) cells to spent culture supernatants of the MRSA strain USA300 induced an increase in mitochondrial ROS production and ATP release that was inhibited by pretreatment with the ROS scavenger glutathione (GSH). ATP secretion involved activation of probenecid-sensitive pannexin 1 channels and bafilomycin A1-dependent exocytosis. ATP exocytosis was inhibited by an antagonist peptide targeting the Receptor for Advanced Glycation End (RAGE) products suggesting that RAGE activation was involved in regulating vesicular ATP release. ATP secretion produced a sustained increase in intracellular Ca 2+ concentration which was dependent upon Ca 2+ uptake from the extracellular solution. Moreover, the sustained JE2-induced Ca 2+ response was not observed in spent supernatants from the less virulent S. aureus agrA mutants used to stimulate hBE cells whereas media from fadX and codY mutants produced responses similar to JE2. Furthermore, wildtype, fadX and codY supernatants evoked secretion of the type-2 inflammatory cytokine IL-33, whereas no response was elicited by media from the less virulent argA mutant. These findings indicate that exposure to secreted virulence factors from S. aureus induces oxidative stress in hBE cells that leads to ATP secretion, sustained Ca 2+ uptake and IL-33 secretion, which has been previously shown to induce type-2 inflammation in airways. This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.
Change in opioid use following spinal cord stimulation: a systematic review and meta-analysis
Soleymani, Hunter , Morsi, Mahmoud , Kopacz, Kira, Karri, Jay , Goudman, Lisa , Hussain, Nasir , Javed, Saba , D’Souza, Ryan S. , D'Souza, Ryan S , Karri, Jay , Javed, Saba

Regional Anesthesia & Pain Medicine | May 12, 2026 | Volume: No volume available | Issue: No issue available | Pages: rapm-2026-107603

10.1136/rapm-2026-107603 | PMID 42120103 Get It

Importance Chronic pain is a leading cause of disability, and many affected patients rely on long-term opioid therapy despite its unfavorable adverse effect profile. Spinal cord stimulation is an established therapy for chronic pain that may secondarily reduce opioid consumption by providing sustained analgesia. Objective To quantify changes in opioid use following spinal cord stimulation implantation for the treatment of chronic pain through a systematic review and meta-analysis. Data sources We conducted a comprehensive search of MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Scopus from each database’s inception to July 1, 2024. Study selection We included studies describing patients who underwent spinal cord stimulator implantation for the treatment of chronic pain. A total of 2,784 potential studies were identified and screened by multiple independent reviewers, yielding a final total of 43 studies included in the systematic review. Data extraction and synthesis Data extraction was completed by multiple independent reviewers following Preferred Reporting Items for Systematic Reviews and Meta-Analysis and Meta-analysis Of Observational Studies in Epidemiology guidelines. A random effects model with Hartung-Knapp-Sidik-Jonkman adjustment was used to estimate pooled estimates. Certainty assessment was performed following the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. Main outcome(s) and measure(s) The primary outcomes were change in continuous opioid use (ie, morphine milligram equivalent (MME)) and categorical opioid use (yes/no) from preimplantation to 12 months following spinal cord stimulator implantation. Results Meta-analysis of 12 month continuous MME use comprising 22 study comparisons (1,666 individuals) revealed a weighted mean difference of −18.06 MME (95% CI −24.41 to −11.70; 95% prediction interval −38.29 to 2.17; p<0.001). Meta-analysis of categorical opioid use at 12 months comprising 24 study comparisons (1,527 individuals) revealed an OR of 0.47 (95% CI 0.30 to 0.75; 95% prediction interval 0.10 to 2.11; p=0.003), signifying lower odds of opioid continuation. Conclusions and relevance Spinal cord stimulation is associated with reduced opioid dose consumption and increased odds of opioid cessation at 12 months postimplantation compared with baseline in patients with chronic pain; however, both of these conclusions are supported by evidence of very low GRADE certainty. PROSPERO registration number CRD42024574921.
Biochemical Recurrence Irradiation or Observation ( BRIO ) in patients with prostate cancer: protocol for a randomised control trial
Wei, Nancy, Phillips, Ryan M., Kwon, Eugene, Stish, B.J., Ehman, Eric C. , Lucien, Fabrice, O'Byrne, Jamie, Bobek, Olivia , Andrews, Jack R. , Boorjian, S., Orme, Jacob J., Sharma, Vidit, Wei, Nancy , Wei, Nancy , Stish, Brad J, Lucien, Fabrice , Bobek, Olivia , Lucien, Fabrice , Shi, Qian , Park, Sean S. , Orme, Jacob J. , Sharma, Vidit

BJU International | May 12, 2026 | Volume: 138 | Issue: 3 | Pages: 403-408

10.1111/bju.70305 | PMID 42117295 Get It

Background The optimal management of biochemical recurrence (BCR) after radical prostatectomy (RP) remains controversial, particularly in the absence of clinical or radiographic evidence of disease. Salvage radiotherapy (SRT) remains standard of care, but it is unclear whether SRT benefits patients when modern imaging with a multiparametric magnetic resonance imaging (mpMRI) and prostate‐specific membrane antigen‐positron emission tomography/computed tomography (PSMA‐PET/CT) are negative for local recurrence. Retrospective data comparing SRT to observation for such patients is fraught with selection bias, underscoring the need for a prospective randomised controlled trial. Study Design and Methods The Biochemical Recurrence Irradiation or Observation (BRIO) is a randomised study under the DIVINE trial framework (NCT06378866) enrolling men with BCR (prostate‐specific antigen [PSA] level ≥0.2, up to 1.5 ng/mL) after RP with no radiographic evidence of recurrence on mpMRI and PSMA‐PET/CT. Major inclusion criteria include age ≥18 years, biochemically recurrent prostate cancer after RP with a PSA level between 0.2 and 1.5 ng/mL, and no local or metastatic recurrence on imaging. A total of 312 patients will be enrolled. Participants are randomised 1:1 to standard‐of‐care SRT followed by surveillance (Group A), or initial observation with subsequent image‐guided therapy at radiographic progression (Group B). Based on historical analysis, a total of 30 metastasis events provides 80% power to detect a significant improvement (hazard ratio 0.5 corresponding to a 5‐year metastasis‐free proportion of 80.7% in the control group and 89.8% in the experimental group with one‐sided type I error rate of 0.15). All participants undergo baseline blood collection to measure prostate cancer‐extracellular vesicles and cell‐free DNA for biomarker development. Participants are followed in a 16‐week cycle with serial PSA measurements, repeat imaging if PSA doubles, safety assessment, and patient‐reported outcomes. Endpoints The primary endpoint is distant recurrence‐free survival at 5‐years using a 12‐month landmark to mitigate bias arising from differing assessment schedules for patients receiving optional 6 months of androgen deprivation therapy. Key secondary outcomes include time to hormone therapy, quality of life measures, adverse effects, and novel blood and urine biomarkers. Conclusion The BRIO study will clarify the clinical benefit of immediate SRT vs observation with image‐guided intervention in mpMRI and PET‐negative BCR after RP.
Reliability of remote self‐administered Web‐based digital cognitive measures and comparison to in‐person neuropsychological tests: Stricker Learning Span, Symbols Test, and the Mayo Test Drive Screening Battery Composite
Hughes, Morgan A., Frank, Ryan D. , Taylor, Rita L. , Fan, Winnie Z. , Christianson, Teresa J., Kremers, Walter K. , Stricker, John L. , Lucas, John A. , Aduen, Paula, Graff‐Radford, Neill R., Graff-Radford, Jonathan, Petersen, Ronald C., Aduen, Paula A., Kremers, Walter K , Hughes, Morgan A., Machulda, Mary M. , Hassenstab, Jason , Mielke, Michelle M. , Day, Gregory S. , Graff‐Radford, Neill R. , Jack, Clifford R. , Graff‐Radford, Jonathan , Petersen, Ronald C. , Stricker, Nikki H.

Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring | May 11, 2026 | Volume: 18 | Issue: 2 | Pages: No page available

10.1002/dad2.70338 | PMID 42125541 Get It

Abstract INTRODUCTION We describe the reliability of remote self‐administered digital cognitive measures completed via the Mayo Test Drive (MTD) web‐based platform. METHODS A total of 1846 participants (mean age = 70, SD = 12, range 31–101; 48% male; 96% White; 99% non‐Hispanic; 97% cognitively unimpaired) with two to four complete MTD sessions at ∼7.5‐month intervals were included. Test‐retest reliability was assessed using single‐rating, absolute‐agreement, and two‐way mixed intraclass correlation coefficients (ICCs) with 95% confidence intervals. ICCs for in‐person‐administered traditional neuropsychological measures were compared to MTD for a subset of 244 participants. Analyses also compared reliability across demographic, residential, and session context subgroups. RESULTS Reliability was good for the MTD Composite (total ICC = 0.79 [0.77, 0.80]), and moderate‐to‐good for the primary outcome variables for each MTD subtest (total ICCs 0.70–0.83 for Stricker Learning Span and Symbols). The reliability of the remote self‐administered MTD was similar to in‐person‐administered cognitive measures. DISCUSSION MTD showed moderate‐to‐good reliability, supporting its use in longitudinal monitoring.