Validity and reliability of the Persian version of Dementia Knowledge Assessment Scale and Dementia Attitude Scale in Iranian health workers about Alzheimer’s disease

There are various questionnaires in the world to assess the level of knowledge and attitudes of people about Alzheimer’s disease. Dementia Knowledge Assessment Scale (DKAS) and Dementia Attitude Scale (DAS) questionnaires are two well-known questionnaires in this field, respectively. The purpose of this study is translation and psychometrics evaluation of two questionnaires DKAS and DASS and appropriating it with the culture of Iranian society.

Initially, the questionnaires were translated. The content validity of the questionnaires was assessed by 10 experts. To measure content validity, inter-rater agreement (IRA), relevancy and clarity of each of the items and the tool as a whole and comprehensiveness were calculated.  Reliability was measured with Cronbach’s alpha and intra -cluster correlation.

The Inter Rater Agreement to relevancy and clarity of the tool was 94% and 76%, respectively. The overall relevancy and clarity of the tool calculated through the mean, was 99.2% and 96%, respectively. Eventually its comprehensiveness was 100%. Overall Cronbach’s alpha in knowledge and attitude scale was 0.71 and 0.76, respectively. The highest ICC value was 0.97 and the lowest was 0.81 in the knowledge tool and 0.97 in the attitude tool in both areas.

The results of this study show that the tools used to measure the level of knowledge and attitudes of health care providers about Alzheimer’s disease have good content validity and reliability.