ABSTRACT
In a period when the budding field of neurosurgery was believed to have little promise, Dr Alfred Washington Adson founded and led the first neurosurgical department at Mayo Clinic. He was not without reservations-surgical intervention for neurological conditions was rarely pursued because of poor outcomes and high complication rates, and Dr Adson acknowledged his early concerns about the future of neurosurgery in his memoirs. However, his education, mentorship, his training, and his first neurosurgical cases helped to shape the impact he ultimately had on the field and his legacy as a neurosurgeon. Dr Adson trained with several renowned Mayo general surgeons, notably his mentor Dr Emil Beckman, whose desire for operative precision shaped Dr Adson's drive to develop his own skills as a surgeon. Two years into his residency, he became the youngest staff surgeon and was tasked with managing the neurosurgical cases at Mayo. The five neurosurgical cases overseen by Dr Adson in the next year illuminated the opportunity for neurosurgery to drastically improve the lives of patients. Dr Adson, given the option of continuing as either a general surgeon or a neurosurgeon, ultimately chose to pursue neurosurgery. This article seeks to provide a historical perspective on the neurosurgeon Dr Alfred Washington Adson using primary and secondary accounts from the Mayo archives, highlighting his contributions to the early understanding of intracranial pathology and how his early experiences as a trainee developed into a personal passion for self-improvement, education, and advocacy for health care in America.
Subject(s)
Neurosurgery , Surgeons , Male , Humans , Neurosurgeons , Washington , Neurosurgical ProceduresABSTRACT
OBJECTIVE: The objective of this article is to describe the effects of patient demographics and examination factors on patient-reported experience in outpatient MRI examinations. METHODS: This institutional review board-waived, HIPPA-compliant quality improvement study evaluated outpatient MRI appointments from March 2021 to January 2022 using a postappointment survey consisting of a 5-point emoji scale and text-based feedback. Patient demographics and examination information were extracted from electronic medical records. Ratings ≤ 3 were categorized as negative, and ratings ≥ 4 were categorized as positive. Continuous variables were analyzed using the Kruskal-Wallis test, and categorical variables were analyzed using the Fisher's exact test. A P value less than .05 was considered significant. A natural language processing algorithm was trained and validated to categorize patient feedback. RESULTS: A total of 3,636 patients responded to the survey. Positive ratings had a higher proportion of male respondents compared with negative ratings (47.9% versus 37.0%, P = .004). Examination characteristics were also grouped by positive or negative rating. Patients who endured longer examination time (median 54.0 min versus 44.0 min, P < .001) and longer wait time after check-in (median 61.6 min versus 46.2 min, P < .001) were more likely to give negative ratings. The most common themes of free text feedback included excellent service (84.3%), on-time service (8.4%), and comfortable intravenous line placement (0.4%). Most common negative feedback included long wait times (10.5%), poor communication (8.4%), and physical discomfort during the examination (4.2%). CONCLUSION: Male gender, short examination duration, and on-time start were associated with positive patient ratings.
Subject(s)
Outpatients , Patient Satisfaction , Humans , Male , Magnetic Resonance Imaging , Patient Outcome Assessment , DemographyABSTRACT
OBJECTIVE: To evaluate differences in quantitative features between poorly versus highly rated patient ratings of radiology reports. METHODS: A HIPAA-compliant, IRB-waived study was performed from October 2019 to June 2021. Patients completed an optional 2-question survey ("How helpful was the report?" with a 5-star scale and an open text box) embedded into the patient portal, and reports were assessed for readability and brevity. Quantitative analyses were performed between poorly (≤3 stars) and highly rated (>3 stars) CT and MRI reports, including the use of structured reporting, number of words, words per sentence, Flesch Reading Ease, and Flesh-Kincaid Grade level within the findings and impression sections of the radiology reports. A two-tailed nonparametric Mann U Whitney test was performed for continuous variables and Chi2 for categorical variables. RESULTS: Of the 490 responses, all 135 evaluating CT or MR were included (27%). 106/135 (78%) of the patients gave high ratings (score of 4 or 5). 46/135 (34%), the radiology reports were in a structured format. The proportion of highly rated reports were significantly higher for structured than freeform reports (93.5 vs. 70.8%, p = 0.002). In the findings section, highly rated reports had a lower Flesch Reading Ease score than poorly rated reports (19.6 vs. 28.9, p <0.01). No significant differences were observed between number of words (p=0.27), words per sentence (p=0.94), and Flesh-Kincaid Grade level (p=0.09) in the findings section. In the impression section, no differences were observed between highly vs. poorly rated reports among the measured parameters. CONCLUSION: Patients preferred highly rated reports that were structured and had lower Flesch Reading Ease scores in the findings section.
Subject(s)
Magnetic Resonance Imaging , Radiology , Humans , Comprehension , ReadingABSTRACT
BACKGROUND: Withholding prophylactic anticoagulation from patients with aneurysmal subarachnoid hemorrhage (aSAH) before external ventricular drain (EVD) removal or replacement remains controversial. This study analyzed whether prophylactic anticoagulation was associated with hemorrhagic complications related to EVD removal. METHOD: All aSAH patients treated from January 1, 2014, to July 31, 2019, with an EVD placed were retrospectively analyzed. Patients were compared based on the number of prophylactic anticoagulant doses withheld for EVD removal (> 1 vs. ≤ 1). The primary outcome analyzed was deep venous thrombosis (DVT) or pulmonary embolism (PE) after EVD removal. A propensity-adjusted logistic-regression analysis was performed for confounding variables. RESULTS: A total of 271 patients were analyzed. For EVD removal, > 1 dose was withheld from 116 (42.8%) patients. Six (2.2%) patients had a hemorrhage associated with EVD removal, and 17 (6.3%) patients had a DVT or PE. No significant difference in EVD-related hemorrhage after EVD removal was found between patients with > 1 versus ≤ 1 dose of anticoagulant withheld (4 of 116 [3.5%] vs. 2 of 155 [1.3%]; p = 0.41) or between those with no doses withheld compared to ≥ 1 dose withheld (1 of 100 [1.0%] vs. 5 of 171 [2.9%]; p = 0.32). After adjustment, withholding > 1 dose of anticoagulant versus ≤ 1 dose was associated with the occurrence of DVT or PE (OR 4.8; 95% CI, 1.5-15.7; p = 0.009). CONCLUSIONS: In aSAH patients with EVDs, withholding > 1 dose of prophylactic anticoagulant for EVD removal was associated with an increased risk of DVT or PE and no reduction in catheter removal-associated hemorrhage.
Subject(s)
Pulmonary Embolism , Subarachnoid Hemorrhage , Humans , Subarachnoid Hemorrhage/complications , Subarachnoid Hemorrhage/surgery , Retrospective Studies , Anticoagulants/adverse effects , Drainage/adverse effects , Ventriculostomy/adverse effectsABSTRACT
OBJECTIVE: In adults with cervical spinal cord injury (SCI), transcutaneous spinal stimulation (scTS) has improved upper extremity strength and control. This novel noninvasive neurotherapeutic approach combined with training may modulate the inherent developmental plasticity of children with SCI, providing even greater improvements than training or stimulation alone. Because children with SCI represent a vulnerable population, we first must establish the safety and feasibility of any potential novel therapeutic approach. The objectives of this pilot study were to determine the safety, feasibility, and proof of principle of cervical and thoracic scTS for short-term effect on upper extremity strength in children with SCI. MATERIALS AND METHODS: In this nonrandomized, within-subject repeated measure design, seven participants with chronic cervical SCI performed upper extremity motor tasks without and with cervical (C3-C4 and C6-C7) and thoracic (T10-T11) site scTS. Safety and feasibility of using cervical and thoracic sites scTS were determined by the frequency count of anticipated and unanticipated risks (eg, pain, numbness). Proof-of-principle concept was tested via change in force production during hand motor tasks. RESULTS: All seven participants tolerated cervical and thoracic scTS across the three days, with a wide range of stimulation intensities (cervical sites = 20-70 mA and thoracic site = 25-190 mA). Skin redness at the stimulation sites was observed in four of 21 assessments (19%) and dissipated in a few hours. No episode of autonomic dysreflexia was observed or reported. Hemodynamic parameters (systolic blood pressure and heart rate) remained within stable limits (p > 0.05) throughout the assessment time points at baseline, with scTS, and after the experiment. Hand-grip and wrist-extension strength increased (p < 0.05) with scTS. CONCLUSIONS: We indicated that short-term application of scTS via two cervical and one thoracic site is safe and feasible in children with SCI and resulted in immediate improvements in hand-grip and wrist-extension strength in the presence of scTS. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number for the study is NCT04032990.
ABSTRACT
Data regarding the impact of pacing on outcomes after transcatheter aortic valve implantation (TAVI) is evolving especially with regards to pre-existing permanent pacemaker (PPM). We examined the impact of new and previous PPM on the clinical and hemodynamic outcomes after SAPIEN-3 TAVI. We included all consecutive patients who underwent transfemoral TAVI using SAPIEN-3 valve from 2015 to 2018 at our institution. Among 1,028 patients, 10.2% required a new PPM within 30 days, whereas 14% had a pre-existing PPM. The presence of either previous or new PPM had no impact on the 3-year mortality (log-rank p = 0.6) or 1-year major adverse cardiac and cerebrovascular events (log-rank p = 0.65). New PPM was associated with lower left ventricular (LV) ejection fraction (LVEF) at both 30 days (54.4 ± 11.3% vs 58.4 ± 10.1%, p = 0.001) and 1 year (54.2 ± 12% vs 59.1 ± 9.9%, p = 0.009) than no PPM. Similarly, previous PPM was associated with worse LVEF at 30 days (53.6 ± 12.3%, p <0.001) and 1 year (55.5 ± 12.1%, p = 0.006) than no PPM. Interestingly, new PPM was associated with lower 1-year mean gradient (11.4 ± 3.8 vs 12.6 ± 5.6 mm Hg, p = 0.04) and peak gradient (21.3 ± 6.5 vs 24.1 ± 10.4 mm Hg, p = 0.01), despite no baseline differences. Previous PPM was also associated with lower 1-year mean gradient (10.3 ± 4.4 mm Hg, p = 0.001) and peak gradient (19.4 ± 8 mm Hg, p <0.001) and higher Doppler velocity index (0.51 ± 0.12 vs 0.47 ± 0.13, p = 0.039). Moreover, 1-year LV end-systolic volume index was higher with new (23.2 ± 16.1 vs 20 ± 10.8 ml/m2, p = 0.038) and previous PPM (24.5 ± 19.7, p = 0.038) than no PPM. Previous PPM was associated with higher moderate-to-severe tricuspid regurgitation (35.3% vs 17.7%, p <0.001). There were no differences regarding the rest of the studied echocardiographic outcomes at 1 year. In conclusion, new and previous PPM did not affect 3-year mortality or 1-year major adverse cardiac and cerebrovascular events; however, they were associated with worse LVEF, higher 1-year LV end-systolic volume index, and lower mean and peak gradients on follow-up than no PPM.
Subject(s)
Aortic Valve Stenosis , Heart Valve Prosthesis , Pacemaker, Artificial , Transcatheter Aortic Valve Replacement , Humans , Transcatheter Aortic Valve Replacement/adverse effects , Treatment Outcome , Aortic Valve Stenosis/complications , Echocardiography , Ventricular Function, Left , Aortic Valve/diagnostic imaging , Aortic Valve/surgeryABSTRACT
Background Stereotactic radiosurgical rhizolysis of the trigeminal nerve is an established modality increasingly employed to alleviate the symptoms of refractory trigeminal neuralgia. This study analyzes the academic impact of the top 100 cited articles on the radiosurgical management of trigeminal neuralgia. Methods The Scopus database was searched for articles containing "radiosurgery" and one or more of "trigeminal neuralgia," "trigeminus neuralgia," and "tic douloureux." The top 100 articles written in English were arranged in descending order by citation count. Documents were evaluated for authors, publication year, journal and impact factor, total citations, nationality, study type, radiosurgical modality, and the affiliated institution. Quantitative and qualitative analyses were performed on the data. Results The most cited articles were published between 1971 and 2019. The average citation per year was 4.3. The most targeted anatomic area was the "root entry zone" or proximal portion of the cisternal segment of the trigeminal nerve. The most utilized modality was Gamma Knife radiosurgery. The country with the highest number of publications was the United States. Thirty-six percent of the articles were published in the Journal of Neurosurgery . Lunsford, Kondziolka, Flickinger, and Régis, respectively, were the most frequently listed co-authors. The most prolific institute was the University of Pittsburgh Medical Center. Conclusion Stereotactic radiosurgery is an important modality in the management of medically or surgically refractory trigeminal neuralgia. This analysis assesses its contributions over the past five decades to identify trends in treatment practices for neurosurgeons and to highlight areas where further study is needed.
ABSTRACT
Moyamoya disease is a rare disorder associated with progressive intracranial arterial stenosis with fragile, small collateralization that gives an angiographic appearance of a puff of smoker or, in Japanese, "moya-moya". We report a case of coronary artery ostial occlusive disease as an extracranial manifestation of Moyamoya. In the case, we demonstrate that thigh risk features of cardiac positron emission tomography (PET) that ultimately lead to the diagnosis of coronary artery occlusion.
Subject(s)
Moyamoya Disease , Humans , Moyamoya Disease/complications , Moyamoya Disease/diagnostic imaging , Tomography, X-Ray Computed , Angiography , Risk FactorsABSTRACT
INTRODUCTION: Permanent perioperative vision loss is caused by ischemic optic neuropathy (ION) or central retinal artery occlusion (CRAO). Whereas diffusion restriction of the optic nerve (ON) on brain magnetic resonance imaging has been previously reported in perioperative posterior ION (PION), there are no reports of ON diffusion restriction in patients diagnosed with acute perioperative CRAO. We present a case of perioperative CRAO to highlight this neuroimaging finding for neuroradiologists and neurologists. CASE REPORT: A 71-year-old male without vascular risk factors underwent maxillary bilateral antrostomy and septoplasty for chronic sinusitis. Twenty to thirty minutes upon awakening, he complained of painless left eye vision loss. Ophthalmoscopic examination showed retinal whitening, segmented arterioles, and hyperemic disc. Brain MR-diffusion weighted imaging/apparent diffusion coefficient revealed ON diffusion restriction in the proximal segment. Despite attempted reperfusion, left eye remained with no light perception at 6 months. Patients undergoing nonocular surgeries who develop perioperative vision loss related to PION may exhibit ON diffusion restriction but usually have normal ophthalmoscopic findings. CRAO shows retinal whitening, edema, segmentation of arterioles, and cherry red spot on ophthalmoscopy. A recent study reported that ON diffusion restriction in nonperioperative CRAO cases has a sensitivity and specificity of 55% and 70% to 100%. Here, PION was initially considered based on imaging. However, given the neuro-ophthalmic findings, a proximal embolus in the central retinal artery, obstructing its entrance into the proximal ON was deemed more likely. CONCLUSION: We highlight that proximal ON diffusion restriction on brain magnetic resonance imaging can be diagnostic of proximal thromboembolic CRAO. Future studies should evaluate the diagnostic utility and accuracy of MR-diffusion weighted imaging/apparent diffusion coefficient in perioperative visual loss.
Subject(s)
Optic Neuropathy, Ischemic , Retinal Artery Occlusion , Retinal Artery , Male , Humans , Aged , Retinal Artery Occlusion/etiology , Retina , Optic Nerve , Optic Neuropathy, Ischemic/complications , Blindness/complicationsABSTRACT
BACKGROUND: While many current and aspiring neurosurgeons are looking to supplement their clinical practices with leadership positions, there has not been research characterizing current leadership positions such as fellowship directors (FDs) in neurosurgery to provide insight into objective qualities that distinguish these individuals from the rest of the workforce. This study aims to outline the current characterization of spine, endovascular, pediatric, and stereotactic and functional neurosurgery fellowship directors. METHODS: A list of accredited neurosurgical fellowship programs located within the US and their respective directors was acquired through the AANS Neurosurgical Fellowship Training Program Directory. This study obtained educational, demographic, institutional, research, and professional background variables through curriculum vitae, institutional profiles, personal websites, emails, and the Scopus database. RESULTS: Of the 152 FDs analyzed, 143 (94%) were male, 9 (6%) were female, and the mean age was 52.2±8.5 years. The mean Scopus H-index and mean total citations for all FDs was 27±15.7 and 3782.1±4526.7, respectively. Furthermore, the majority of FDs were Caucasian (69.1%), followed by Asian (20.4%), Black or African American (5.3%), and Hispanic or Latino (5.3%). The mean number of years as FD was 8.9±7.2. CONCLUSIONS: This analysis showed neurosurgery fellowship directors are primarily Caucasian males. Neurosurgery training pedigree seems to play a role in FD attainment. In addition, these directors are largely distinguished by their research productivity. This analysis serves as an insight into the current climate for students aspiring to serve as academic leaders in the field of neurosurgery.
Subject(s)
Internship and Residency , Neurosurgery , Humans , Male , Female , Child , Adult , Middle Aged , Neurosurgery/education , Fellowships and Scholarships , Neurosurgical Procedures/education , NeurosurgeonsABSTRACT
ABSTRACT: Carpal tunnel syndrome (CTS) is an entrapment neuropathy affecting the median nerve. Prevalence is estimated at 4% to 5% of the population. A solid understanding of the anatomy, presentation, and diagnostics is key to efficient diagnosis and appropriate referral. Both surgical and nonsurgical interventions have led to improved clinical outcomes. Clinicians who have an in-depth knowledge of CTS symptoms and treatment options can prepare patients and streamline referrals for improved patient outcomes.
Subject(s)
Carpal Tunnel Syndrome , Humans , Carpal Tunnel Syndrome/diagnosis , Carpal Tunnel Syndrome/etiology , Carpal Tunnel Syndrome/therapy , Median Nerve/surgeryABSTRACT
OBJECTIVES: Diffusion weighted imaging hyperintensity (DWI-H) has been described in the retina and optic nerve during acute central retinal artery occlusion (CRAO). We aimed to determine whether DWI-H can be accurately identified on standard brain magnetic resonance imaging (MRI) in non-arteritic CRAO patients at two tertiary academic centers. MATERIALS AND METHODS: Retrospective cross-sectional study that included all consecutive adult patients with confirmed acute non-arteritic CRAO and brain MRI performed within 14 days of CRAO. At each center, two neuroradiologists masked to patient clinical data reviewed each MRI for DWI-H in the retina and optic nerve, first independently then together. Statistical analysis for inter-rater reliability and correlation with clinical data was performed. RESULTS: We included 204 patients [mean age 67.9±14.6 years; 47.5% females; median time from CRAO to MRI 1 day (IQR 1-4.3); 1.5 T in 127/204 (62.3%) and 3.0 T in 77/204 (37.7%)]. Inter-rater reliability varied between centers (κ = 0.27 vs. κ = 0.65) and was better for retinal DWI-H. Miss and error rates significantly differed between neuroradiologists at each center. After consensus review, DWI-H was identified in 87/204 (42.6%) patients [miss rate 117/204 (57.4%) and error rate 11/87 (12.6%)]. Significantly more patients without DWI-H had good visual acuity at follow-up (p = 0.038). CONCLUSIONS: In this real-world case series, differences in agreement and interpretation accuracy among neuroradiologists limited the role of DWI-H in diagnosing acute CRAO on standard MRI. DWI-H was identified in 42.6% of patients and was more accurately detected in the retina than in the optic nerve. Further studies are needed with standardized novel MRI protocols.
Subject(s)
Retinal Artery Occlusion , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Diffusion Magnetic Resonance Imaging , Female , Humans , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Male , Middle Aged , Optic Nerve/diagnostic imaging , Reproducibility of Results , Retina/pathology , Retinal Artery Occlusion/diagnostic imaging , Retinal Artery Occlusion/therapy , Retrospective StudiesABSTRACT
BACKGROUND: The United States is projected to face increasing physician-workforce shortages. However, the shortage in the neurosurgical workforce has not yet been characterized. In the present study, we outlined the current state of the neurosurgical workforce by quantifying the divide between the number of practicing neurosurgeons and the U.S. METHODS: The Medicare Physician National Medicare database was queried from 2014 to 2019 to obtain the numbers of practicing neurosurgeons, which were compared with the population counts from the U.S. Census data. RESULTS: From 2014 to 2019, the total increase in neurosurgeons per capita was 9.4%. The Northeast neurosurgeons per capita rate (NPCR) increased by 17.1%, the South NPCR by 3.4%, the Midwest NPCR by 13.3%, and the West NPCR by 12.5%. In all regions, except for the West, the surgeon per capita ratio had decreased from 2017 to 2019. The greatest increase in the number of surgeons was 2018 to 2019 (n = 214). In 2014, the states with the lowest NPCRs were Vermont, Arkansas, and New Mexico. In 2019, these included Nevada, New Mexico, and Vermont. As of 2020, 56.6% of the neurosurgeons had practiced for >20 years. CONCLUSIONS: Although the national NPCR has slowly increased during the past 5 years, a more recent decrease occurred within the last 3 years. Additionally, with almost 57% of surgeons having been practicing for >20 years, concern exists regarding whether current practices can sustain increasing patient needs. The results from the present study indicate that further investigation is warranted regarding the factors contributing to this shortage and the steps that can be taken to increase the production of well-trained neurosurgeons.
Subject(s)
Neurosurgery , Surgeons , Aged , Aging , Humans , Medicare , Neurosurgeons , United States , WorkforceABSTRACT
Cardiovascular events have a major impact on overall outcomes after liver transplantation. Today's transplant patients are older than those in the past and therefore are more likely to have coexisting cardiac comorbidities. In addition, pathophysiologic effects of advanced liver disease on the circulatory system pose challenges in perioperative management. This review discusses important preoperative, intraoperative, and postoperative cardiac considerations in patients undergoing liver transplant.
Subject(s)
Liver Diseases , Liver Transplantation , Heart , Humans , Postoperative Complications , Postoperative PeriodABSTRACT
BACKGROUND: Peripheral nerve surgery is one of the smallest neurosurgical subspecialties. It is hypothesized that the number of neurosurgeons performing these procedures has declined over the last decade due to many factors, including limited training opportunities and lower compensation relative to other subspecialties. METHODS: Data for physicians who performed peripheral nerve surgical procedures (PNSPs) were obtained from the Medicare Provider Utilization Database and used to calculate the total number of procedures performed by physicians of each specialty for each year. The Physician Fee Schedule Look-Up Tool was used to determine reimbursement rates for the top 5 PNSPs for neurosurgeons, which were then adjusted for inflation using the U.S. Bureau of Labor's Consumer Price Index Inflation Calculator. RESULTS: From 2012 to 2019, the top 3 contributing specialties were orthopedic surgery, urology, and hand surgery. Both the percentage of PNSPs performed by neurosurgeons and the number of neurosurgeons performing PNSPs decreased. Between 2000 and 2020, the average reimbursement for the commonly identified codes 64721, 64718, 64722, and 64718 decreased, whereas the reimbursement for 64555 (implantation of peripheral nerve neurostimulator electrodes) increased. CONCLUSIONS: Despite an overall increase in number of PNSPs, the percentage of PNSPs performed by neurosurgeons decreased from 2012 to 2019. There was overall workforce exit among neurosurgical peripheral nerve specialists over time. From 2000 to 2020, the average reimbursement for most PNSPs has decreased. Further investigation is needed to establish factors contributing to these trends and how they may be mitigated.
Subject(s)
Insurance, Health, Reimbursement , Medicare , Aged , Humans , Neurosurgical Procedures , Peripheral Nerves/surgery , United States , WorkforceSubject(s)
Ambulatory Care , Physicians , Adult , Humans , Office Visits , Practice Patterns, Physicians'ABSTRACT
In children with spinal cord injury (SCI), scoliosis due to trunk muscle paralysis frequently requires surgical treatment. Transcutaneous spinal stimulation enables trunk stability in adults with SCI and may pose a non-invasive preventative therapeutic alternative. This non-randomized, non-blinded pilot clinical trial (NCT03975634) determined the safety and efficacy of transcutaneous spinal stimulation to enable upright sitting posture in 8 children with trunk control impairment due to acquired SCI using within-subject repeated measures study design. Primary safety and efficacy outcomes (pain, hemodynamics stability, skin irritation, trunk kinematics) and secondary outcomes (center of pressure displacement, compliance rate) were assessed within the pre-specified endpoints. One participant did not complete the study due to pain with stimulation on the first day. One episode of autonomic dysreflexia during stimulation was recorded. Following hemodynamic normalization, the participant completed the study. Overall, spinal stimulation was well-tolerated and enabled upright sitting posture in 7 out of the 8 participants.
Subject(s)
Posture/physiology , Spinal Cord Injuries/therapy , Spine/physiology , Adolescent , Biomechanical Phenomena , Child , Child, Preschool , Female , Humans , Male , Pilot ProjectsABSTRACT
A well conducted randomised controlled trial (RCT) is extremely important in the field of cardiovascular medicine. At the same time, it is equally important to understand the strengths and limitations of any RCT, and internal variability is a concept in clinical trials that is poorly understood. Variability in a clinical trial may be introduced at an individual level or during measurement, sampling, or conduct of the trial. It is not the same as internal validity, which is a broader concept of accuracy; to be valid, a study should minimise variability and have sound methodology. There are various steps that may be followed to minimise the internal variability in a clinical trial. One aspect of great importance is the adjudication process, which should be done meticulously and is often a step that is overlooked. It is important to standardise each step as much as possible, to ensure consistency and reduce noise at all levels. The concepts discussed in this review may serve as a roadmap to limit the influence of internal variability and maximise internal validity of RCT results.