Related Experiment Video
Updated: May 3, 2026
Behavioral Assessment of Manual Dexterity in Non-Human Primates
Published on: November 11, 2011
Manual dexterity aptitude testing: a soap carving study
Christopher G Tang1, Raymond L Hilsinger1, Raul M Cruz1
1Department of Head and Neck Surgery, Kaiser Permanente Medical Center Oakland, Oakland, California.
Importance:
Currently there are few validated metrics for predicting surgical skill among otolaryngology residency applicants.
Objective:
To determine whether manual dexterity aptitude testing in the form of soap carving during otolaryngology residency interviews at Kaiser Permanente Medical Center Oakland predicts surgical skill at the time of graduation from otolaryngology residency programs.
Design, Setting, And Participants:
This study was conducted to determine how applicants with the best and worst soap carvings compared at the time of graduation with respect to various metrics including visuospatial ability and manual dexterity. Over the last 25 years, applicants to the residency program at Kaiser Permanente Oakland were required to carve soap during their residency interview. The 3 best and 3 worst soap carvings from 1990 through 2006 were determined. Of the individuals who carved those soaps, 62 qualified for the study and matriculated into otolaryngology residency programs.
Interventions:
Surveys were sent to the 62 individuals' residency programs to evaluate those individuals on a 5-point Likert scale in various categories as well as to rank those individuals as being in the top 50% or bottom 50% of their graduating class.
Main Outcomes And Measures:
All else being equal, we hypothesized that applicants who had the manual dexterity and visuospatial skills to accurately carve a bar of soap would more likely possess the skills necessary to become a good surgeon.
Results:
There was no difference between individuals with the best soap carvings and those with the worst soap carvings in all categories: cognitive knowledge, visuospatial ability, manual dexterity, decision making, and overall score (P > .10 for all categories). There was a 95% response rate, with 35 of 37 residency programs responding and 59 of 62 surveys returned.
Conclusions And Relevance:
Manual dexterity aptitude testing in the form of soap carving does not appear to correlate with surgical skill at the time of graduation. Further studies need to be conducted to determine the role of manual dexterity and visuospatial aptitude testing in the otolaryngology application process.
