April 2020 HSC Section 4 - Plastic and Reconstructive Problems

This 2019-20 Home Study Course Section 4 does not include discussion of any drugs and devices that have not been approved by the United States Food and Drug Administration.

Disclaimer The information contained in this activity represents the views of those who created it and does not necessarily represent the official view or recommendations of the American Academy of Otolaryngology – Head and Neck Surgery Foundation. June 9, 2020: Section 4 suggested exam submission deadline. August 6, 2020, midnight EST: deadline for all 2019-20 HSC exams and evaluations to be submitted.

EVIDENCE BASED MEDICINE The AAO-HNSF Education Advisory Committee approved the assignment of the appropriate level of evidence to support each clinical and/or scientific journal reference used to authenticate a continuing medical education activity. Noted at the end of each reference, the level of evidence is displayed in this format: [EBM Level 3] .

Oxford Centre for Evidence-based Medicine Levels of Evidence (May 2001) Level 1

Randomized 1 controlled trials 2 or a systematic review 3 (meta-analysis 4 ) of randomized controlled trials 5 . Prospective (cohort 6 or outcomes) study 7 with an internal control group or a systematic review of prospective, controlled trials. Retrospective (case-control 8 ) study 9 with an internal control group or a systematic review of retrospective, controlled trials. Case series 10 without an internal control group (retrospective reviews; uncontrolled cohort or outcome studies).

Level 2

Level 3

Level 4

Expert opinion without explicit critical appraisal, or recommendation based on physiology/bench research.

Level 5

Two additional ratings to be used for articles that do not fall into the above scale. Articles that are informational only can be rated N/A , and articles that are a review of an article can be rated as Review. All definitions adapted from Glossary of Terms, Evidence Based Emergency Medicine at New York Academy of Medicine at www.ebem.org . 1 A technique which gives every patient an equal chance of being assigned to any particular arm of a controlled clinical trial. 2 Any study which compares two groups by virtue of different therapies or exposures fulfills this definition. 3 A formal review of a focused clinical question based on a comprehensive search strategy and structure critical appraisal. 4 A review of a focused clinical question following rigorous methodological criteria and employing statistical techniques to combine data from independently performed studies on that question. 5 A controlled clinical trial in which the study groups are created through randomizations. 6 This design follows a group of patients, called a “cohort”, over time to determine general outcomes as well as outcomes of different subgroups. 7 Any study done forward in time. This is particularly important in studies on therapy, prognosis or harm, where retrospective studies make hidden biases very likely. 8 This might be considered a randomized controlled trial played backwards. People who get sick or have a bad outcome are identified and “matched” with people who did better. Then, the effects of the therapy or harmful

exposure which might have been administered at the start of the trial are evaluated. 9 Any study in which the outcomes have already occurred before the study has begun. 10 This includes single case reports and published case series.