Objective: Chloral Hydrate is the most commonly used sedative for Auditory Brainstem Response (ABR) test. The aim of this study was to retrospectively analyze the safety and effectiveness of Chloral Hydrate in patients undergoing ABR tests through a single-center and large sample size cross-sectional study. Methods: Data were collected from December 2015 to March 2022, which included 7,176 ABR tests (6,106 patients). Basic information was collected, then telephone follow-up was conducted for patients with two or more consecutive tests less than 60 days, and administration method, failure performance, and adverse events were collected. Total sedation failure rate, sedation failure rates in different age groups (≤0.5 years, 0.5-3 years, 3-12 years, ≥12 years) and incidence of adverse events were calculated. Results: A total of 4,967(69.21%) ABR tests were younger than 3 years of age. The sedation failure rate was 3.11% with a Chloral Hydrate dose of 30 mg/kg of weight, which ranged from 1.44% to 4.31% in different age groups. In the sedation failure tests, insufficient sedation was found in 74.44% of the tests. The incidence of adverse events was 0.35%, with most commonly vomiting. Conclusion: The sedation failure rate and the incidence of adverse events in this study are relatively low compared with other previous studies, and Chloral Hydrate can be considered a safe and effective sedative with the permissible dose. However, there were still many patients who failed to complete the test due to insufficient sedation (mostly infants and children), which imply that alternative sedatives with easier preparation process are needed.

Objective: Numerous clinical practice guidelines (CPGs) for the corona virus disease 2019 (COVID-19) have been developed since its outbreak. To date, however, the methodological quality of these guidelines has not been fully evaluated. Quality evaluation of the guidelines is to facilitate the clinic practitioners in diagnosis and treatment of the COVID-19. Methods: The evaluation was conducted by searching seven databases and government organizations websites (December 2019 to March 2020). Four assessors assessed the quality of the CPGs independently with the Appraisal of Guidelines for Research & Evaluation II (AGREE II) instrument. For domain scores (0-100%), >60% were considered of sufficient quality, and >80% of good quality. Results: Of 471 retrieved records, 20 guidelines were included. The median score for the domain of scope and purpose was 56.9% (range 40.3–90.3%) and nine guidelines scored >60%, among which three guidelines scored >80%. The median score for the stakeholder involvement domain was 7% (range 0–65.3%) and only two guidelines scored >60%. Nine guidelines scored 0% in this domain. The median score for the rigour of development domain was 0% (range 0–91.7%) and fourteen guidelines scored 0% in this domain. The median score for the clarity of presentation domain was 30.6% (range 13.9–91.7%) and six guidelines scored >60%, among which three guidelines scored >80%. The median score for the applicability domain was 0% (0–57.3%) and eleven guidelines scored 0% in this domain. The median score for the editorial independence domain was 0% (0–100%): four guidelines scored >80%. Discussions：Three guidelines were recommendable, and four were recommendable with modification in the stakeholder involvement, the rigour of development, and the applicability domains. Our results could contribute to improve development of future guidelines, and affect the reasonable selection and use of guidelines in clinical practice.