title: [Reliability and validity of a handedness questionnaire].
abstract: OBJECTIVE
  In this study, the validity and reliability of the hand preference item of a 13-item questionnaire adapted from Chapman and Chapman (1987) were investigated.
  
  
  METHODS
  This questionnaire requires subjects to indicate which hand they usually use for various actions as follows: writing, drawing, throwing, using a hammer, using a toothbrush, using an eraser on paper, using scissors, holding a match when striking it, stirring a can of paint, using a spoon, using a screwdriver, twisting off the lid of a jar, and using a knife. Each item was scored as "1" for right, "2" for either, or "3" for left, and the handedness of subjects was scored from 13 (the strongest right-hand preference) to 39 (the strongest left-hand preference). In this study, 449 subjects filled in the questionnaire, and 43 subjects attended the test-retest study 3 weeks after the first examination. In order to determine the validity of the questionnaire, fine motor performance was measured using a finger tapping task, and the eye and foot preferences of the subjects were evaluated.
  
  
  RESULTS
  The test-retest reliability (r=.993) and internal consistency (Cronbach's Alpha=.97) were found to be high. In item-total score analysis, the best single item was "using a hammer", while the worst item was "twisting off the lid of a jar". Factor analysis yielded two factors, skilled and unskilled activities. Handedness scores were found to show a significant correlation with foot preference scores and the dominance score of the finger tapping task.
  
  
  CONCLUSIONS
  The results suggest that the handedness questionnaire is reliable and valid in measuring handedness.
authors.affiliation: Ankara U Tip Fak, Fizyoloji AD, Bilişsel Nörofizyoloji Birimi.
authors.forename: Erhan
authors.initials: E
authors.lastname: Nalçaci
authors.forename: Canan
authors.initials: C
authors.lastname: Kalaycioğlu
authors.forename: Emel
authors.initials: E
authors.lastname: Güneş
authors.forename: Metehan
authors.initials: M
authors.lastname: Ciçek