title: Leniency and halo effects in marking undergraduate short research projects.
abstract: BACKGROUND
  Supervisors are often involved in the assessment of projects they have supervised themselves. Previous research suggests that detailed marking sheets may alleviate leniency and halo effects. We set out to determine if, despite using such a marking schedule, leniency and halo effects were evident in the supervisors' marking of undergraduate short research projects (special study modules (SSM)).
  
  
  METHODS
  Review of grades awarded by supervisors, second markers and control markers to the written reports of 4th year medical students who had participated in an SSM during two full academic years (n = 399). Paired t-tests were used to compare mean marks, Pearson correlation to look at agreement between marks and multiple linear regression to test the prediction of one mark from several others adjusted for one another.
  
  
  RESULTS
  There was a highly significant difference of approximately half a grade between supervisors and second markers with supervisors marking higher. (t = 3.12, p < 0.01, difference in grade score = 0.42, 95% CI for mean difference 0.18-0.80). There was a high correlation between the two marks awarded for performance of the project and the written report by the supervisor (r = 0.75), but a low-modest correlation between supervisor and second marker (r = 0.28). Linear regression analysis of the influence of the supervisors' mark for performance on their mark for the report gave a non-significant result. This suggests a leniency effect but no halo effect.
  
  
  CONCLUSIONS
  This study shows that with the use of structured marking sheet for assessment of undergraduate medical students, supervisors marks are not associated with a halo effect, but leniency does occur. As supervisor assessment is becoming more common in both under graduate and postgraduate teaching new ways to improve objectivity in marking and to address the leniency of supervisors should be sought.
authors.affiliation: Community Health Sciences, University of Edinburgh, Edinburgh, Scotland, UK. brian.mckinstry@ed.ac.uk
authors.forename: Brian H
authors.initials: BH
authors.lastname: McKinstry
authors.forename: Helen S
authors.initials: HS
authors.lastname: Cameron
authors.forename: Robert A
authors.initials: RA
authors.lastname: Elton
authors.forename: Simon C
authors.initials: SC
authors.lastname: Riley
mesh_terms: D000288:Administrative Personnel; D000328:Adult; D004504:Education, Medical, Undergraduate; D004521:Educational Measurement / Q000379:methods* / Q000592:standards; D005180:Faculty, Medical; D006801:Humans; D015588:Observer Variation; D010865:Pilot Projects; D018794:Problem-Based Learning / Q000458:organization & administration*; D015203:Reproducibility of Results; D012106:Research / Q000193:education* / Q000592:standards