Participants
This cross-sectional study was conducted in Chongqing, China, from July to August in 2017, using multistage cluster sampling method to enroll participants. The 40 districts or counties of Chongqing are divided into five levels, according to the gross regional product of 2016. In the first stage of sampling, one district or county from each of the five levels was randomly chosen, and finally, Yuzhong, Banan, Qijiang, Fengdu, and Wulong were chosen. In the second stage of sampling, one town or block were selected randomly from each of the five districts or counties chosen in the first stage. All the dentists and non-dental dentists (NDDs) from all the legal hospitals or clinics in the selected towns or blocks were asked if he or she would like to participant in the study. A total of 437 doctors were asked if they would like to participate the study, of whom 403 doctors (243 doctors were from non-dental departments and 160 were dentists) completed the questionnaires.
Study design
The self-administered questionnaire was particularly designed for the study population (doctors) based on the knowledge-attitude-behavior (KAB) model 34, it included four parts: (1) Demographic characteristics (2) Knowledge related to brushing teeth with powered toothbrush (3) Attitude related to brushing teeth with powered toothbrush (4) Behaviors related to brushing teeth with powered toothbrush.
Prior to the implementation of this study, the questionnaire was piloted with 37 doctors (15 dentists and 22 non-dental doctors), revisions were made accordingly, and after the repeated discussions with experts in epidemiology and stomatology, the final version of the questionnaire had acceptable content validity. And the internal consistency of the KAB questionnaire was acceptable (Cronbach’s alpha = 0.910).
The knowledge part of powered toothbrush was assessed by 6 single-choice questions, about the knowing of powered toothbrush and its effects on tooth brushing. Each question was assigned a score of 1, and the total score for this part ranged from 0 to 6, a high score indicates a higher level of knowledge on the topic. Example of the questions included: “Do you think that powered toothbrush can clear plaque more effectively, compared with manual toothbrush”?
The attitude part of was assessed by 3 single-choice questions on the attitudes of using and recommending powered toothbrush. Each question consisted of three levels with a score ranging from 0 to 2, which imply “certainly not” (score=0), “maybe” (score=1), and “Sure” (score=2). The total score for this item may range from 0 to 6, and a high score indicates a good attitude towards recommending powered toothbrush. Example of the questions included: “Would you like to recommend powered toothbrushes to others”?
Behaviors regarding powered toothbrush was assessed by 4 single-choice questions on the used and the recommendation powered toothbrush. Each question was assigned a score of 1, and the total score for this part ranged from 0 to 4. A high score indicates a good behavior regarding brushing teeth with powered toothbrush. Example of the questions included: “Are you using powered toothbrush to brush your teeth everyday”?
The scores of knowledge, attitude and behaviors were classified into two levels: “need to be strengthen” (≤60 percent) and “satisfactory” (>60percent) 35
The study was performed in accordance with the World Medical Association Declaration of Helsinki and ethics approval was obtained from the Ethical Committee of the Chongqing Medical University. The participation of the respondents was voluntary, and they were included in the study after submitting signed informed consent.
Quality control
The investigators were selected from dental students who were willing to participate in this study by an interview. Prior to the survey, the investigators were trained in relevant knowledge and the implementation of the survey. Only the researchers who were familiar with the objectives and methods of this study, as well as having good interview skills and the experience in dealing with potentially sensitive issues were allowed to conduct the survey. Each of the questionnaire was checked to avoid mistakes.
Statistical analysis
The Statistical Package for Social Sciences (SPSS) software version 19.0 (SPSS Inc., USA) was applied to analyze the data. The descriptive data were expressed as mean ± standard deviation (SD) or proportions (%). Chi-square test was performed to test the differences among the categorical variables A p <0.05 was considered statistically significant. Multiple linear regression analysis was used to assess the association between sociodemo graphic and KAB.