1. Critically appraising a paper Furrat Amen, MRCS(Eng), DOHNS, MSc November 2005

2. Journal Well known? International/local peer review Authors on editorial board? Impact factor Important topic?

3. Impact factor For example, the 2003 Impact factor for a journal would be calculated as follows: A = Number of times articles published in 2001-2 were cited in tracked journals during 2003 B = Number of articles published in 2001-2 2003 Impact Factor = A/B

4. Levels of evidence 1a - SR of RCTs 1b - Individual RCT 1c – all or none case series 2a - SR of cohort studies 2b - Individual cohort study 3a - SR of case-control studies 3b - Individual Case-Control Study 4 - Case-series 5 - Expert opinion without explicit critical appraisal, or based on physiology, bench research or "first principles"

5. Authors and Institutions Have the authors published in this area before? What institution? Good Name?

6. Article Expectations of the article Interesting? Other research in the area? Well presented, prepared, clear, informative?

7. Study Prospective / Retrospective Time between onset of symptoms and diagnosis Blind scoring / bias RCT – impartial interpretation of results Multi-centre trial better?

8. Subsection appraisal Title –Does the title do justice to the article and vice- versa Abstract – a good outline? Aims – clear Introduction –Informative and justification for work undertaken

9. Materials and methods Repeatability Well designed study? Well controlled study? Comparable controls? Sufficient numbers for stats Appropriate stats?

10. Results Clear and comprehensive? Authors interpretation correct? Text, figures, graphs, tables, illustrations Your interpretation same as authors?

11. Discussion Data discussed comprehensively? Absence of discussion in areas? Bias Conclusions agree with own interpretations

12. References Up to date Citations from reputable journals? References appropriate? Self references? –number

13. Summary Believe article? Change of views Improvements Read article 2-3 times

14. Long-term effects of Micronized Alloderm Injection for Unilateral Vocal Cord Paralysis A critical review Furrat Amen

15. Summary 20 patients Unilateral vocal cord paralysis Injected with alloderm (derived from cadaveric dermis) Assessment –Questionnaires –Recordings assessed –videostroboscopy

16. Journal Laryngoscope is the official journal of the American Laryngological, Rhinological and Otological Society Well known National and international peer reviewed Authors not on editorial board Impact factor 1.449 Topic is important

17. Authors and Institutions Claudio Milstein –No previous articles on vocal cord injection Lee Akst –No previous articles on vocal cord injection Douglas Hicks –Many articles about voice, but non on injection Tom Abelson –No previous articles on VC injection Marshall Strome –Papers on laryngeal transplantation

18. Institution Cleveland Clinic Foundation –Cleveland, Ohio, USA Not for profit Research and Clinical medicine Established 1921 Outpatients!!!

19. Article Expectations –Long periods of follow-up for 20 patients –Interested – never heard of alloderm before –First described in June 2002 5 articles –Well written, misleading number of patients, but informative

20. Study Retrospective case series (level 4) Time between vocal cord paralysis and injection was 4 to 216 months ? Had another procedure in mean time “voice experts” assessed blindly –Digital voice samples –Videostroboscopy –Not fully blind as all patients had alloderm! Patients were not blind Bias – on 3 patients – retrospective questionnaire

21. Study Twenty patients –Only 8 patients had 12+ months FU Multicentre trial may have increased numbers

22. Title Long term effects ? justified –Only eight patients 12 months + –No mention of mortality shortening FU Abstract skimmed over the shortfalls of study Aims clearly defined but not achieved Introduction – good background and reasoning

23. Materials and methods It could be repeated Design would have been better as a prospective study No controls Low numbers involved

24. Statistics Wilcoxon Signed Rank Test –Non parametric alternative to paired t-test Does not assume a normally distributed population Used for ordinal data (in categories e.g. Likert scale) –Use seems appropriate –Impressive P<0.0001 for bowing and glottic closure P<0.01 for self-perception of voice

25. Results Clear and comprehensive I agreed with interpretation of authors Photo Fig 1 – clearly demonstrates better glottic closure Table 1. Shows demographics and length of FU Table 2. Shows change from best to worst pre and post injection –Glottic closure / bowing / voice perception

26. Tables and Figures Fig.2 and 3 –Repeat data in table 2 Fig. 4 and 5 –Degree of improvement depends on width of graph

27. Discussion Good discussion –Self-critical –“anecdotal” results –Pilot study/case series – similar to a study in Laryngoscope in 2002 but with more than 1 month FU –No discussion about mortality of patients causing short follow up –Conclusion Further investigation needed agree

28. References 17 references 6 references 2000+ One reference from 1911 in German References relevant No self references

29. Summary I do believe article –Viable option for VC injection ?better Had no opinion on topic before Improvements –Multicentre trial –Prospective double blind randomised controlled trial between alloderm and bioplastique –Longer follow-up