Design and Development of Scales in Primary Care: Practical Steps and Statistical Methods

Abstract

This study outlines statistical methods and practical steps for designing and developing valid and reliable questionnaires in primary care. A series of studies on questionnaire development and scale design are reviewed and a standardized process for scale design in the primary care is developed. The process involves key and practical steps in the scale design process as well as statistical methods, which is illustrated with examples of previous relevant studies within the field. The suggested seven-step approach to developing a questionnaire in the primary care is: (1) defining the construction of measurement; (2) generating the pool of items; (3) selecting the scoring system and response format; (4) pre-testing (assessing content validity and face validity, etc.) ; (5) eliminating items by item analysis; (6) evaluating the scale initially, including evaluating the reliability and validity of the scale, and factor analysis or Rasch analysis; (7) re-evaluating the scale to re-examine the nature of the scale, including retesting reliability and constructing validity. In general, the studies on scale design should strictly follow the standardized steps of scale development, and the integrated use of Rasch model and factor analysis can make the measurements more objective.

Keywords

• primary health care|scale development|research design|factor analysis|rasch model