Background Interval colorectal cancers may be associated with a low serrated polyp detection rate (SDR) and advanced adenoma detection rate (AADR). We aimed to determine the SDR and AADR for endoscopists in a United States multicenter cohort. Methods We included average-risk screening colonoscopies from five medical centers in the United States. Endoscopists with data on at least 100 average-risk screening colonoscopies were included. We calculated median SDR and AADR for endoscopists with adequate adenoma detection rates (ADRs) > 25 %. We analyzed the relationship between ADR and SDR, and between ADR and AADR using nonparametric Spearman correlation coefficients, scatter plots, and linear regression. Results We included 3513 screening colonoscopies performed by 26 gastroenterologists. The mean age of patients was 56.8 years (SD 7.4) and 1585 (45 %) were male. All but one endoscopist had an ADR above 25 %. There was a significant positive but modest correlation between ADR and SDR (rho = 0.67, P < 0.01), and between ADR and AADR (rho = 0.56, P < 0.01). For endoscopists with an adequate ADR, median (interquartile range) ADR was 43 % (32.0 % – 48.6 %), median SDR was 8.4 % (7.3 % – 11.4 %), and median AADR was 9.3 % (6.4 % – 12.6 %). Conclusion A significant percentage of endoscopists have either a low SDR or low AADR despite an adequate ADR, justifying the need for separate SDR and AADR benchmarks. Based on our multicenter cohort, endoscopists with adequate ADRs had a median SDR and median AADR of about 8 % and 9 %, respectively.

Radionuclide esophageal scintigraphy (RES) and manometry were used for prospective evaluation of esophageal involvement and disease severity in 11 patients (nine women and two men; median time since diagnosis, 1 year) with progressive systemic sclerosis (PSS). Quantitation of RES included calculation of the percentage of emptying at 30 seconds, while manometry provided measurements of proximal, distal, and lower esophageal sphincter (LES) pressures. The findings of both RES and manometry were abnormal in all 11 patients. There was a high correlation between the percentage of emptying and either distal esophageal pressure (r = .86, P less than .01) or LES pressure (r = .79, P less than .01). No significant correlation was found between the percentage of emptying and proximal esophageal pressure (r = .28, P = .39). RES is a safe, simple procedure that is readily accepted by patients and can be used in place of manometry for the detection and staging of esophageal involvement in PSS.

We prove a moderate deviation principle for the continuous time interpolation of discrete time recursive stochastic processes. The methods of proof are somewhat different from the corresponding large deviation result, and in particular the proof of the upper bound is more complicated. The results can be applied to the design of accelerated Monte Carlo algorithms for certain problems, where schemes based on moderate deviations are easier to construct and in certain situations provide performance comparable to those based on large deviations.

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Radionuclide esophageal scintigraphy is a sensitive test of esophageal function, but its usefulness is not well documented in Barrett esophagus. This technique was prospectively studied in 27 patients with histologically proved Barrett esophagus and 17 patients with biopsy-confirmed reflux esophagitis. The esophageal transit time and percentage of emptying were calculated. The only quantitative parameter of radionuclide esophageal scintigraphy to show a significant difference between the two conditions was the percentage of emptying, which was abnormal in 48% of patients with Barrett esophagus versus 31% of patients with reflux esophagitis. In the latter group, the mean percentage of emptying approached normal (89.5%), while in the former group it was decreased to 82.1% (P less than .05). Neither emptying parameter correlated with length of Barrett esophagus. These data support the hypothesis of inherent esophageal dysmotility in Barrett esophagus. Half of the patients with this condition have impaired esophageal clearance and may benefit from drug therapy.