The questionnaireThe questionnaire

The questionnaire
The questionnaire was consisted of 8 items related to demographic information, 26 items
related to the health belief model constructs including: perceived susceptibility, perceived
severity, perceived benefits, perceived barriers, perceived self efficacy, and 3 items on
reasons for visiting dentist, sources of information, and brushing behavior frequency. The
items derived from previous studies on the topic [11,13,14,20]. A panel of experts consisting
of ten faculty members (eight specialized in health education and two dentists) evaluated the
content validity. Consequently psychometric properties of the questionnaire were examined.
The construct validity was assessed by performing explanatory factor analysis and reliability
was evaluated by assessing internal consistency. The results obtained from explanatory factor
analysis with oblique rotation, indicated a 7-factor solution that jointly accounted for 59.6%
of variance observed. We noticed that ‘perceived severity’ was loaded on two separate factors
(perceived subjective and objective severity) and similarly ‘perceived barriers’ also was
loaded on two parts (perceived physical and perceived psychological barriers). The constructs
and sample items in addition to the Cronbach’s alpha coefficients are shown in Table 1 (the
detailed results are not shown but is available from the main investigator).