Comprehension of 500 safety words: a computer-based methodology. 2 volumes.

  • Iain R. Graydon

Student thesis: Doctoral ThesisDoctor of Philosophy


This thesis investigates the relative comprehensibility of 500 words related to consumer safety using a computer-based methodology. Problems in defining and measuring language comprehension are discussed.

A pilot study explored techniques for assessing the comprehensibility of 40 safety words and 30 safety phrases. Results determined the feasibility of scaling up the research to a large field study.

The main study investigated 500 safety words using questionnaires
containing ten each of the target words. Words were randomised and
partitioned into administratively convenient sets before generating
questionnaires. Questionnaires were tested using national survey

The questionnaire was open-ended and asked respondents for the
meaning of each word in the general context of safety. The verbatim
results formed the primary data base. Seven "qualified" judges
independently categorised the responses according to operationally
defined levels of comprehension. The seven sets of judgements were
analysed for consensus. Frequency analyses were made on the categorised
raw data. The results of several of these analyses were combined to
yield tabulations in which words were ordered according to various
criteria. Subsequent analysis concentrated on words that looked as if
they were either difficult to understand, had provoked significant lack
of agreement across the judges, showed a significant number of
inappropriate responses or failed to have a large enough sample to yield
reliable interpretations. Each word was also analysed by gender and by
predicted verbal ability.

Finally, conclusions and recommendations are made regarding the
methodology and the results it yielded along with shortcomings and
potential extensions.
Date of Award1986
Original languageEnglish


  • language comprehension
  • consumer safety
  • methodology
  • applied psychology

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