Note: NIH: National Institutes of Health; CD: cannot determine; NR: not reported; NA: not applicable. The NIH quality assessment tool for case series studies (https://www.nhlbi.nih.gov/health-topics/study-quality-assessment-tools) contains nine questions: 1 = Was the study question or objective clearly stated?, 2 = Was the study population clearly and fully described, including a case definition?, 3 = Were the cases consecutive?, 4 = Were the subjects comparable?, 5 = Was the intervention clearly described?, 6 = Were the outcome measures clearly defined, valid, reliable, and implemented consistently across all study participants?, 7 = Was the length of follow-up adequate?, 8 = Were the statistical methods well-described?, 9 = Were the results well-described? (source: National Heart, Lung, and Blood Institute; National Institutes of Health; U.S. Department of Health and Human Services) https://www.nhlbi.nih.gov/health-topics/study-quality-assessment-tools.