Cost-Effectiveness Analysis of PET-CT Surveillance After Treatment of Human Papillomavirus-Positive Oropharyngeal Cancer.

OBJECTIVE: To determine the cost-effectiveness of surveillance imaging with PET/CT scan among patients with human papillomavirus-positive oropharyngeal squamous cell carcinoma. STUDY DESIGN: Cost-effectiveness analysis. SETTING: Oncologic care centers in the United States with head and neck oncologic surgeons and physicians. METHODS: We compared the cost-effectiveness of 2 posttreatment surveillance strategies: clinical surveillance with the addition of PET/CT scan versus clinical surveillance alone in human papillomavirus-positive oropharyngeal squamous cell carcinoma patients. We constructed a Markov decision model which was analyzed from a third-party payer's perspective using 1-year Markov cycles and a 30-year time horizon. Values for transition probabilities, costs, health care utilities, and their studied ranges were derived from the literature. RESULTS: The incremental cost-effectiveness ratio for PET/CT with clinical surveillance versus clinical surveillance alone was $89,850 per quality-adjusted life year gained. Flexible fiberoptic scope exams during clinical surveillance would have to be over 51% sensitive or PET/CT scan cost would have to exceed $1678 for clinical surveillance alone to be more cost-effective. The willingness-to-pay threshold at which imaging surveillance was equally cost-effective to clinical surveillance was approximately $80,000/QALY. CONCLUSION: Despite lower recurrence rates of human papillomavirus-positive oropharyngeal cancer, a single PET/CT scan within 6 months after primary treatment remains a cost-effective tool for routine surveillance when its cost does not exceed $1678. The cost-effectiveness of this strategy is also dependent on the clinical surveillance sensitivity (flexible fiberoptic pharyngoscopy), and willingness-to-pay thresholds which vary by country.

Association of Intensive Lifestyle Intervention for Type 2 Diabetes With Labor Market Outcomes.

Importance: An intensive lifestyle intervention (ILI) has been shown to improve diabetes management and physical function. These benefits could lead to better labor market outcomes, but this has not been previously studied. Objective: To estimate the association of an ILI for weight loss in type 2 diabetes with employment, earnings, and disability benefit receipt during and after the intervention. Design, Setting, and Participants: This cohort study included participants with type 2 diabetes and overweight or obesity and compared an ILI with a control condition of diabetes support and education. Data for the original trial were accrued from August 22, 2001, to September 14, 2012. Trial data were linked with Social Security Administration records to investigate whether, relative to the control group, the ILI was associated with improvements in labor market outcomes during and after the intervention period. Difference-in-differences models estimating relative changes in employment, earnings, and disability benefit receipt between the ILI and control groups were used, accounting for prerandomization differences in outcomes for linked participants. Outcome data were analyzed from July 13, 2020, to May 17, 2023. Exposure: The ILI consisted of sessions with lifestyle counselors, dieticians, exercise specialists, and behavioral therapists on a weekly basis in the first 6 months, decreasing to a monthly basis by the fourth year, designed to achieve and maintain at least 7% weight loss. The control group received group-based diabetes education sessions 3 times annually during the first 4 years, with 1 annual session thereafter. Main Outcomes and Measures: Employment and receipt of federal disability benefits (Supplemental Security Income and Social Security Disability Insurance), earnings, and disability benefit payments from 1994 through 2018. Results: A total of 3091 trial participants were linked with Social Security Administration data (60.1% of 5145 participants initially randomized and 97.0% of 3188 of participants consenting to linkage). Among the 3091 with fully linked data, 1836 (59.4%) were women, and mean (SD) age was 58.4 (6.5) years. Baseline clinical and demographic characteristics were similar between linked participants in the ILI and control groups. Employment increased by 2.9 (95% CI, 0.3-5.5) percentage points for the ILI group relative to controls (P = .03) with no significant relative change in disability benefit receipt (-0.9 [95% CI, -2.1 to 0.3] percentage points; P = .13). Conclusions and Relevance: The findings of this cohort study suggest that an ILI to prevent the progression and complications of type 2 diabetes was associated with higher levels of employment. Labor market productivity should be considered when evaluating interventions to manage chronic diseases.

Cost-effectiveness Analysis of Submandibular Gland Preservation With Sialendoscopy for the Management of Sialolithiasis.

OBJECTIVE: To compare the cost-effectiveness of sialendoscopy with gland excision for the management of submandibular gland sialolithiasis. STUDY DESIGN: Cost-effectiveness analysis. SETTING: Outpatient surgery centers. METHODS: A Markov decision model compared the cost-effectiveness of sialendoscopy versus gland excision for managing submandibular gland sialolithiasis. Surgical outcome probabilities were found in the primary literature. The quality of life of patients was represented by health utilities, and costs were estimated from a third-party payer's perspective. The effectiveness of each intervention was measured in quality-adjusted life-years (QALYs). The incremental costs and effectiveness of each intervention were compared, and a willingness-to-pay ratio of $150,000 per QALY was considered cost-effective. One-way, multivariate, and probabilistic sensitivity analyses were performed to challenge model conclusions. RESULTS: Over 10 years, sialendoscopy yielded 9.00 QALYs at an average cost of $8306, while gland excision produced 8.94 QALYs at an average cost of $6103. The ICER for sialendoscopy was $36,717 per QALY gained, making sialendoscopy cost-effective by our best estimates. The model was sensitive to the probability of success and the cost of sialendoscopy. Sialendoscopy must meet a probability-of-success threshold of 0.61 (61%) and cost ≤$11,996 to remain cost-effective. A Monte Carlo simulation revealed sialendoscopy to be cost-effective 60% of the time. CONCLUSION: Sialendoscopy appears to be a cost-effective management strategy for sialolithiasis of the submandibular gland when certain thresholds are maintained. Further studies elucidating the clinical factors that determine successful sialendoscopy may be aided by these thresholds as well as future comparisons of novel technology.

Cost-effectiveness of a Digital Health Intervention for Acute Myocardial Infarction Recovery.

BACKGROUND: Acute myocardial infarction (AMI) is a common cause of hospital admissions, readmissions, and mortality worldwide. Digital health interventions (DHIs) that promote self-management, adherence to guideline-directed therapy, and cardiovascular risk reduction may improve health outcomes in this population. The "Corrie" DHI consists of a smartphone application, smartwatch, and wireless blood pressure monitor to support medication tracking, education, vital signs monitoring, and care coordination. We aimed to assess the cost-effectiveness of this DHI plus standard of care in reducing 30-day readmissions among AMI patients in comparison to standard of care alone. METHODS: A Markov model was used to explore cost-effectiveness from the hospital perspective. The time horizon of the analysis was 1 year, with 30-day cycles, using inflation-adjusted cost data with no discount rate. Currencies were quantified in US dollars, and effectiveness was measured in quality-adjusted life-years (QALYs). The results were interpreted as an incremental cost-effectiveness ratio at a threshold of $100,000 per QALY. Univariate sensitivity and multivariate probabilistic sensitivity analyses tested model uncertainty. RESULTS: The DHI reduced costs and increased QALYs on average, dominating standard of care in 99.7% of simulations in the probabilistic analysis. Based on the assumption that the DHI costs $2750 per patient, use of the DHI leads to a cost-savings of $7274 per patient compared with standard of care alone. CONCLUSIONS: Our results demonstrate that this DHI is cost-saving through the reduction of risk for all-cause readmission following AMI. DHIs that promote improved adherence with guideline-based health care can reduce hospital readmissions and associated costs.

The economics of alternative payment models for pharmaceuticals.

Pharmaceuticals are priced uniformly by convention, but vary in their degree of effectiveness for different disease indications. As more high-cost therapies have launched, the demand for alternative payment models (APMs) has been increasing in many advanced markets, despite their well-documented limitations and challenges to implementation. Among policy justifications for such contracts is the maximization of value given scarce resources. We show that while uniform pricing rules can handle variable effectiveness in efficient markets, market inefficiencies of other kinds create a role for different value-based pricing structures. We first present a stylized theoretical model of efficient interaction among drug manufacturers, payers, and beneficiaries. In this stylized setting, uniform pricing works well, even when treatment effects are variable. We then use this framework to define market failures that result in obstacles to uniform pricing. The market failures we identify include: (1) uncertainty of patient distribution, (2) asymmetric beliefs, (3) agency imperfection by payer, (4) agency imperfection by provider, and (5) patient behavior and treatment adherence. We then apply our insights to real-world examples of alternative payment models, and highlight challenges related to contract implementation.

Reconstruction After Salvage Total Laryngectomy: A Cost-effectiveness Analysis.

OBJECTIVE: To determine the most cost-effective reconstruction method after salvage total laryngectomy. STUDY DESIGN: Cost-effectiveness analysis. SETTING: Tertiary care hospitals with head and neck oncologic and reconstructive surgeons. SUBJECTS AND METHODS: We constructed a Markov-based decision model to compare reconstruction by primary closure to pectoralis flap and free flap after salvage total laryngectomy. The model simulated disease with transition probabilities and health utilities found in primary literature and estimated the average overall cost of each reconstructive method using Medicare billing codes. Effectiveness was compared using quality-adjusted life years (QALYs). One-way and probabilistic sensitivity analyses were performed to scrutinize the conclusions of our model. Reconstruction methods were compared using incremental cost-effectiveness ratios (ICERs). In the United States, less than $150,000 per QALY gained is considered cost-effective (2019 US dollars). RESULTS: Our base case analysis revealed that primary closure was less expensive ($44,370) and yielded more QALYs (0.91) than both pectoralis ($45,163, 0.81 QALYs) and free flap ($46,244, 0.85 QALYs), making it the most cost-effective option. Between flaps, free flap was cost-effective over pectoralis flap (ICER = $27,025/QALY gained). Sensitivity analyses showed primary closure as cost-effective 69% of the time over either flap. These conclusions were sensitive to the health utilities (quality of life) of each method of reconstruction. CONCLUSION: Tissue flaps to augment closure after salvage total laryngectomy are not always the most cost-effective reconstructive option. The long-term morbidity of flap surgery oftentimes outweighs the benefit of lowering fistula rates after surgery. Careful consideration must be taken when advising patients of their reconstructive options.

Do Research Groups Align on an Intervention's Value? Concordance of Cost-Effectiveness Findings Between the Institute for Clinical and Economic Review and Other Health System Stakeholders.

The Institute for Clinical and Economic Review (ICER) employs fixed cost-effectiveness (CE) thresholds that guide their appraisal of an intervention's long-term economic value. Given ICER's rising influence in the healthcare field, we undertook an assessment of the concordance of ICER's CE findings to the published CE findings from other research groups (i.e., "non-ICER" researchers including life science manufacturers, academics, and government institutions). Disease areas and pharmaceutical interventions for comparison were determined based on ICER evaluations conducted from 1 January 2015 to 31 December 2017. A targeted literature search was conducted for non-ICER CE publications using PubMed. Studies had to be conducted from the US setting, include the same disease characteristics (e.g., disease severity; treatment history), incorporate the same pharmaceutical interventions and comparison groups, and present incremental costs per quality-adjusted life-year (QALY) gained from the healthcare sector or payer perspective. Discordance was measured as the proportion of unique interventions that would have had more favorable valuations (i.e., low, intermediate, high value-for-money) if the CE findings from other research groups had been used for decision making instead of ICER's findings. More favorable valuations were defined as transitioning from low value (as determined by ICER) to intermediate or high value (as determined by other researchers) and from intermediate value (as determined by ICER) to high value (as determined by other researchers). Among the 13 non-ICER studies meeting inclusion criteria, six disease areas and 14 interventions were assessed. Of the 14 interventions, a more favorable valuation would have been recommended for ten therapies if the CE ratios from other research groups had been used for decision making instead of ICER's findings, representing a 71.4% (10/14) discordance rate. Moreover, these discrepancies were found in each of the evaluated disease areas, with the largest number of discordant valuations found in rheumatoid arthritis (five out of six interventions were discordant) followed by one valuation each in multiple sclerosis (one out of three), non-small cell lung cancer (one out of two), multiple myeloma (one out of one), high cholesterol (one out of one), and congestive heart failure (one out of one). Our findings indicate high discordance when comparing ICER's appraisals to the CE findings of non-ICER researchers. To understand the value of new interventions, the totality of evidence on the CE of an intervention-including results from ICER and non-ICER modeling efforts-should be considered when making coverage and reimbursement decisions.

Can Pediatric Endoscopists Accurately Assess Their Clinical Competency? A Comparison Across Skill Levels.

BACKGROUND: Assessment is critical to support pediatric endoscopy training. Although trainee engagement in assessment is encouraged, the use of self-assessment and its accuracy among pediatric endoscopists is not well described. We aimed to determine the self-assessment accuracy of novice, intermediate, and experienced pediatric endoscopists. METHODS: Novice (performed <50 previous colonoscopies), intermediate (50-500), and experienced (>1000) pediatric endoscopists from 3 North American academic teaching hospitals each performed a clinical colonoscopy. Endoscopists were assessed in real-time by 2 experienced endoscopists using the Gastrointestinal Endoscopy Competency Assessment Tool for Pediatric Colonoscopy (GiECATKIDS). In addition, participants self-assessed their performance using the same instrument. Self-assessment accuracy between the externally assessed and self-assessed scores was evaluated using absolute difference scores, intraclass correlation coefficients, and Bland-Altman analyses. RESULTS: Forty-seven endoscopists participated (21 novices, 16 intermediates, and 10 experienced). Overall, there was moderate agreement of externally assessed and self-assessed GiECATKIDS total scores with an intraclass correlation coefficient of 0.72 (95% confidence interval, 0.55-0.83). The absolute difference scores among the 3 groups were significantly different (P = 0.005), with experienced endoscopists demonstrating a more accurate self-assessment compared to novices (P = 0.003). Bland-Altman plots revealed that novice endoscopists' self-assessed scores tended to be higher than their externally assessed scores, indicating they overestimated their performance. CONCLUSIONS: We found that endoscopic experience was positively associated with self-assessment accuracy among pediatric endoscopists. Novices were inaccurate in assessing their endoscopic competence and were prone to overestimation of their performances. Our findings suggest novices may benefit from targeted interventions aimed at improving their insight and self-awareness.

Point of care ultrasound training for internal medicine: a Canadian multi-centre learner needs assessment study.

BACKGROUND: Significant gaps currently exist in the Canadian internal medicine point-of-care ultrasound (POCUS) curriculum. From a learner's perspective, it remains unknown what key POCUS skills should be prioritized. This needs assessment study seeks to establish educational priorities for POCUS for internal medicine residents at five Canadian residency training programs. METHODS: All internal medicine trainees [postgraduate year (PGY) 1-5] from five internal medicine residency training programs in Canada (n = 598) were invited to complete an online survey on 15 diagnostic POCUS applications, 9 bedside procedures, and 18 POCUS knowledge items. For POCUS applications and procedures, participants were asked how applicable they are to patient care in internal medicine and the participants' reported skills in those domains. Self-reported knowledge and skills were rated on a 5-point Likert scale, where 1 = very poor and 5 = very good. Applicability was rated, where 1 = not at all applicable and 5 = very applicable. RESULTS: A total of 253 of 598 residents (42%) participated in our study. Data from one centre (n = 15) was removed because of low response rate (15%) and significant baseline differences between those trainees and the remaining participants. Of the remaining analyzable data from four training programs (n = 238), participants reported highest applicability to internal medicine for the following applications and procedures: identifying ascites/free fluid [mean applicability score of 4.9 ± standard deviation (SD) 0.4]; gross left ventricular function (mean 4.8 ± SD 0.5) and pericardial effusion (mean 4.7 ± SD 0.5); thoracentesis (mean score 4.9 ± SD 0.3), central line insertion (mean 4.9 ± SD 0.3), and paracentesis (mean 4.9 ± SD 0.3), respectively. Overall reported knowledge/skills was low, with skill gaps being the highest for identifying deep vein thrombosis (mean gap 2.7 ± SD 1.1), right ventricular strain (mean 2.7 ± SD 1.1), and gross left ventricular function (mean 2.7 ± SD 1.0). CONCLUSIONS: Many POCUS applications and procedures were felt to be applicable to the practice of internal medicine. Significant skill gaps exist in the four Canadian training programs included in the study. POCUS curriculum development efforts should target training based on these perceived skill gaps.

Impact of experience on self-assessment accuracy of clinical colonoscopy competence.

BACKGROUND AND AIMS: Self-assessment is important for life-long learning and a recommended assessment method for endoscopy skills. Prior literature has not investigated self-assessment accuracy of colonoscopic competence in the clinical setting. This study aimed to determine the self-assessment accuracy of novice, intermediate, and experienced endoscopists. METHODS: Novice (performed <50 previous colonoscopies), intermediate (50-500), and experienced (>1000) endoscopists from 5 hospitals each performed a clinical colonoscopy. Video recordings of procedures were independently assessed by 2 blinded expert endoscopists by using the Gastrointestinal Endoscopy Competency Assessment Tool (GiECAT). Externally assessed and self-assessed GiECAT scores were defined as the mean of the 2 video-based ratings and as participants' own assigned ratings, respectively. Self-assessment accuracy between the externally assessed and self-assessed scores was evaluated by using absolute difference scores, intraclass correlation coefficients, and the Bland-Altman analysis. RESULTS: Twenty novice, 10 intermediate, and 10 experienced endoscopists participated. There was moderate agreement of externally assessed and self-assessed GiECAT scores, with an intraclass correlation coefficient of 0.65 (95% confidence interval, 0.44-0.80). The absolute difference scores among the 3 groups were significantly different (P = .002), with experienced endoscopists demonstrating a more accurate self-assessment ability compared with novices (P = .002). Bland-Altman plots suggest that novice and experienced endoscopists tend to overrate and underrate their clinical competence, respectively; no specific trends were associated with intermediates. CONCLUSION: Participants demonstrated moderate self-assessment accuracy of clinical competence. Endoscopist experience was positively associated with self-assessment accuracy; novices demonstrated lower self-assessment accuracy compared with experienced endoscopists. Moreover, novices tended to overestimate their performances. Novice endoscopists may benefit from targeted interventions to improve self-assessment accuracy.

Cost-effectiveness analysis of vagal nerve blocking for morbid obesity.

OBJECTIVES: To assess the lifetime cost-effectiveness of intermittent, reversible vagal nerve blocking (via the implantable weight loss device vBloc) therapy versus conventional therapy as treatment for patients who are class 2 obese with diabetes and for those who are class 3 obese with or without diabetes, who have found pharmacotherapy and behavioral therapies ineffective, but are not prepared or willing to undergo current bariatric surgical options. STUDY DESIGN: A cost-effectiveness model was designed to simulate weight loss, diabetes remission, and costs in patients with obesity undergoing vagal nerve blocking therapy versus conventional therapy. METHODS: The model compared 2 treatment arms, vagal nerve blocking therapy and conventional therapy, and for each treatment arm included 4 health states based on body mass index (BMI) class. Using Monte Carlo simulation, patients entered the model one at a time and could transition between health states by experiencing BMI change. The model focused on change in BMI and diabetes remission as predictors of healthcare costs, health-related quality of life, and survival. Inputs for vagal nerve blocking effectiveness were obtained from the ReCharge trial; however, remaining inputs were estimated from published literature. Incremental cost-effectiveness ratios (ICERs) were evaluated in terms of cost per quality-adjusted life-year (QALY) gained. RESULTS: ICERs for vagal nerve blocking versus conventional therapy in patients who were class 2 and class 3 obese were estimated to be $17,274 and $21,713 per QALY gained, respectively. Sensitivity analyses showed results to be robust to reasonable variation in model inputs, with the upper limit of ICERs remaining below $30,000 for all sensitivity analysis scenarios assessed. CONCLUSIONS: Vagal nerve blocking therapy provides a cost-effective alternative to conventional therapy in patients who are class 2 obese with diabetes and in those who are class 3 with or without diabetes.

Attendance at Religious Services, Prayer, Religious Coping, and Religious/Spiritual Identity as Predictors of All-Cause Mortality in the Black Women's Health Study.

Previous longitudinal studies have consistently shown an association between attendance at religious services and lower all-cause mortality, but the literature on associations between other measures of religion and spirituality (R/S) and mortality is limited. We followed 36,613 respondents from the Black Women's Health Study from 2005 through December 31, 2013 to assess the associations between R/S and incident all-cause mortality using proportional hazards models. After control for numerous demographic and health covariates, together with other R/S variables, attending religious services several times per week was associated with a substantially lower mortality rate ratio (mortality rate ratio = 0.64, 95% confidence interval: 0.51, 0.80) relative to never attending services. Engaging in prayer several times per day was not associated with mortality after control for demographic and health covariates, but the association trended towards a higher mortality rate ratio when control was made for other R/S variables (for >2 times/day vs. weekly or less, mortality rate ratio = 1.28, 95% confidence interval: 0.99, 1.67; P-trend < 0.01). Religious coping and self-identification as a very religious/spiritual person were associated with lower mortality when adjustment was made only for age, but the association was attenuated when control was made for demographic and health covariates and was almost entirely eliminated when control was made for other R/S variables. The results indicate that service attendance was the strongest R/S predictor of mortality in this cohort.

Cost-effectiveness of brexpiprazole adjunctive treatment for major depressive disorder.

BACKGROUND: Major depressive disorder (MDD) is a debilitating psychiatric illness with a high cost burden. This analysis evaluates the cost-effectiveness of adjunctive brexpiprazole versus comparator branded adjunctive treatment for MDD and background antidepressant therapy (ADT) alone from a US payer perspective. METHODS: An economic model was developed to assess the cost-effectiveness of brexpiprazole versus comparator adjunctive treatment and ADT alone on total direct medical costs using a 6-week cycle time frame for a total of 48 weeks, with treatment response and remission as primary outcomes. The model consisted of 3 parts, 1 to represent the acute treatment phase and 2 to represent the maintenance stage. RESULTS: In the base-case analysis, brexpiprazole as reference treatment resulted in cost per additional responder ranging from $19,442-$48,745 and cost per additional remitter ranging from $27,196-$71,839 versus comparator treatments over 48 weeks. Sensitivity analyses showed treatment with brexpiprazole was more costly, but more clinically effective in all probabilistic simulations. LIMITATIONS: This representation of disease natural history over 48 weeks may not account for all possible health states. Resource utilization on treatment was estimated using the resource use data from previous trials, and may overestimate medical costs compared to the real-world setting. Treatment comparators were limited to branded therapies, and head-to-head studies were not available to obtain data inputs. CONCLUSION: Compared to other branded adjunctive therapies, brexpiprazole increases response and remission at 6 weeks; medical care cost savings were observed with the use of brexpiprazole. These findings may assist clinicians and formulary decision makers when selecting treatment for MDD.

Neighborhood and Individual Socioeconomic Status and Asthma Incidence in African American Women.

OBJECTIVE: Individual socioeconomic status (SES) has been associated with asthma incidence but whether neighborhood SES has an influence is unknown. We assessed the contributions of neighborhood socioeconomic status (SES), neighborhood housing density, neighborhood racial composition, and individual SES to the development of adult-onset asthma in Black women, accounting for other known or suspected risk factors. DESIGN AND PARTICIPANTS: Prospective cohort study conducted among 47,779 African American women followed with biennial health questionnaires from 1995 to 2011. METHODS AND MAIN OUTCOME MEASURES: Incident asthma was defined as new self-report of doctor-diagnosed asthma with concurrent use of asthma medication. We assessed neighborhood SES, indicated by census variables representing income, education, and wealth, and housing density and % African American population, as well as individual SES, indicated by highest education of participant/spouse. Cox proportional hazards models were used to derive multivariable hazard ratios (HRs) and 95% CIs for the association of individual SES and neighborhood variables with asthma incidence. RESULTS: During a 16-year follow-up period, 1520 women reported incident asthma. Neighborhood factors were not associated with asthma incidence after control for individual SES, body mass index, and other factors. Compared with college graduates, the multivariable HR for asthma was 1.13 (95% CI 1.00-1.28) for women with some college education and 1.23 (95% CI 1.05-1.44) for women with no more than a high school education. CONCLUSIONS: Individual SES, but not neighborhood SES or other neighborhood factors, was associated with the incidence of adult-onset asthma in this population of African American women.

Gastrointestinal Endoscopy Competency Assessment Tool: reliability and validity evidence.

BACKGROUND: Rigorously developed and validated direct observational assessment tools are required to support competency-based colonoscopy training to facilitate skill acquisition, optimize learning, and ensure readiness for unsupervised practice. OBJECTIVE: To examine reliability and validity evidence of the Gastrointestinal Endoscopy Competency Assessment Tool (GiECAT) for colonoscopy for use within the clinical setting. DESIGN: Prospective, observational, multicenter validation study. Sixty-one endoscopists performing 116 colonoscopies were assessed using the GiECAT, which consists of a 7-item global rating scale (GRS) and 19-item checklist (CL). A second rater assessed procedures to determine interrater reliability by using intraclass correlation coefficients (ICCs). Endoscopists' first and second procedure scores were compared to determine test-retest reliability by using ICCs. Discriminative validity was examined by comparing novice, intermediate, and experienced endoscopists' scores. Concurrent validity was measured by correlating scores with colonoscopy experience, cecal and terminal ileal intubation rates, and physician global assessment. SETTING: A total of 116 colonoscopies performed by 33 novice (<50 previous procedures), 18 intermediate (50-500 previous procedures), and 10 experienced (>1000 previous procedures) endoscopists from 6 Canadian hospitals. MAIN OUTCOME MEASUREMENTS: Interrater and test-retest reliability, discriminative, and concurrent validity. RESULTS: Interrater reliability was high (total: ICC=0.85; GRS: ICC=0.85; CL: ICC=0.81). Test-retest reliability was excellent (total: ICC=0.91; GRS: ICC=0.93; CL: ICC=0.80). Significant differences in GiECAT scores among novice, intermediate, and experienced endoscopists were noted (P<.001). There was a significant positive correlation (P<.001) between scores and number of previous colonoscopies (total: ρ=0.78, GRS: ρ=0.80, CL: Spearman's ρ=0.71); cecal intubation rate (total: ρ=0.81, GRS: Spearman's ρ=0.82, CL: Spearman's ρ=0.75); ileal intubation rate (total: Spearman's ρ=0.82, GRS: Spearman's ρ=0.82, CL: Spearman's ρ=0.77); and physician global assessment (total: Spearman's ρ=0.90, GRS: Spearman's ρ=0.94, CL: Spearman's ρ=0.77). LIMITATIONS: Nonblinded assessments. CONCLUSION: This study provides evidence supporting the reliability and validity of the GiECAT for use in assessing the performance of live colonoscopies in the clinical setting.

The gastrointestinal endoscopy competency assessment tool for pediatric colonoscopy.

OBJECTIVES: Validated assessment tools are required to support competency-based education. We aimed to assess the reliability and validity of the Gastrointestinal Endoscopy Competency Assessment Tool for Pediatric Colonoscopy (GiECATKIDS), an instrument developed by 41 North American experts using Delphi methodology. METHODS: GiECATKIDS consists of a 7-item global rating scale (GRS) and an 18-item checklist (CL). An attending physician assessed 104 colonoscopies performed at 3 North American hospitals by 56 endoscopists, including 25 novices (<50 previous procedures), 21 intermediates (50-250), and 10 advanced endoscopists (>500). Another observer rated procedures to assess interrater reliability using intraclass correlation coefficient (ICC). Test-retest reliability was measured with ICC comparing endoscopists' first and second procedure scores. Discriminative validity was examined by comparing experience level with scores. Concurrent validity was assessed by correlating scores with colonoscopy experience, cecal and terminal ileal intubation rates, and physician global assessment. RESULTS: Interrater reliability of the GiECATKIDS was high (total: ICC = 0.88; GRS: ICC = 0.79; CL: ICC = 0.89). Test-retest reliability was excellent (total: ICC = 0.94; GRS: ICC = 0.94; CL: ICC = 0.84). GiECATKIDS total, GRS, and CL scores differed significantly among novice, intermediate, and advanced endoscopists (P < 0.001). There was a significant positive correlation (P < 0.001) between scores and number of previous colonoscopies (total: ρ = 0.91, GRS: ρ = 0.92, CL: ρ = 0.84), cecal intubation rate (total: ρ = 0.82, GRS: ρ = 0.85, CL: ρ = 0.77), ileal intubation rate (total: ρ = 0.82, GRS: ρ = 0.82, CL: ρ = 0.80), and physician global assessment (total: ρ = 0.95, GRS: ρ = 0.94, CL: ρ = 0.89). CONCLUSIONS: The GiECATKIDS demonstrates strong reliability and validity as a measure of performance of pediatric colonoscopy that can be used to support training and assessment.

Evolution of cooperation in spatial traveler's dilemma game.

Traveler's dilemma (TD) is one of social dilemmas which has been well studied in the economics community, but it is attracted little attention in the physics community. The TD game is a two-person game. Each player can select an integer value between [Formula: see text] and [Formula: see text] ([Formula: see text]) as a pure strategy. If both of them select the same value, the payoff to them will be that value. If the players select different values, say [Formula: see text] and [Formula: see text] ([Formula: see text]), then the payoff to the player who chooses the small value will be [Formula: see text] and the payoff to the other player will be [Formula: see text]. We term the player who selects a large value as the cooperator, and the one who chooses a small value as the defector. The reason is that if both of them select large values, it will result in a large total payoff. The Nash equilibrium of the TD game is to choose the smallest value [Formula: see text]. However, in previous behavioral studies, players in TD game typically select values that are much larger than [Formula: see text], and the average selected value exhibits an inverse relationship with [Formula: see text]. To explain such anomalous behavior, in this paper, we study the evolution of cooperation in spatial traveler's dilemma game where the players are located on a square lattice and each player plays TD games with his neighbors. Players in our model can adopt their neighbors' strategies following two standard models of spatial game dynamics. Monte-Carlo simulation is applied to our model, and the results show that the cooperation level of the system, which is proportional to the average value of the strategies, decreases with increasing [Formula: see text] until [Formula: see text] is greater than the critical value where cooperation vanishes. Our findings indicate that spatial reciprocity promotes the evolution of cooperation in TD game and the spatial TD game model can interpret the anomalous behavior observed in previous behavioral experiments.