Abstract
Purpose: :
In stark contrast to the wealth of knowledge and understanding about patient anxiety within primary health care, almost nothing is know about anxiety in optometric practice. The aim of this research was to develop an ‘Optometric Anxiety Scale’ which could quantify patient anxiety within an optometric setting and thus provide a measure with which to evaluate the ability of various interventions to reduce patient anxiety.
Methods: :
The scale was developed using both traditional methods and Rasch analysis. On the basis of information from focus groups, published literature about anxiety and discussions with optometrists an 83–item, 5 response option (strongly agree to strongly disagree) questionnaire was developed and piloted on 348 young adults. The validity of the responses was assessed and principal component analysis (PCA) was performed to identify the principal factors, each including questions with a high degree of internal consistency. The resulting shorter 30–item questionnaire was piloted in optometric practice. Rasch analysis was subsequently undertaken to remove items from the scale in order to ensure unidimensionality and improve targeting of the items.
Results: :
One hundred and forty eight questionnaires were completed in two different optometric practices. A total of six questionnaires were removed from the sample either due to missing demographic data or where more than 33% of the questionnaire was incomplete. Items with positive valence were recoded, so that a high value represented higher anxiety. Patient fit statistics were checked to identify if there were any rogue responders contributing to poor item fit statistics. Inspection of the initial person–item map revealed that the questionnaire was targeted towards the higher levels of anxiety. Reduction of the categories from five to three improved the targeting. Items were removed from the scale principally driven by infit and outfit statistics. The final ten item questionnaire has good infit and outfit statistics, Cronbach alpha = 0.87 and person separation = 2.23.
Conclusions: :
The "Optometric Anxiety Scale" is a short self–report questionnaire that may be used to evaluate patient anxiety in optometric practice.
Keywords: quality of life • stress response • clinical (human) or epidemiologic studies: outcomes/complications