This study has been approved by the Research Deputy of Tehran University of Medical Sciences, approval code 99-1-259-48164. Also, the study has been approved by the Ethics Committee of Tehran University of Medical Sciences, ethics code: IR.TUMS.IKHC.REC.1399.112. All the participants consented to take part in the study by written consent.
1.1 Questionnaire Design
To design a BHQ, after an extensive literature review and several discussion panels with 7 general surgeons, breast surgeons, and gynecologists, 14 questions were designed based on the Likert scale, including always (almost always), usually, sometimes, rarely, and never as answer options; to assess the women’s perception toward their BH.
1.2 Validity Assessment
1.2.1 Face Validity
Face validity is used to assess whether a questionnaire is appropriate for the measurement of what is expected to be measured in general . To do this, the approved questions were given to 10 experts to examine their form, comprehensibility, sequence, and fluency.
1.2.2 Content Validity
To conduct content validity , the designed questionnaire was given to 5 health experts experienced in the field of breast diseases and 5 knowledgeable participants; and each question was scored in terms of relevancy, clarity, and simplicity. Responses were categorized into four groups including not relevant, somewhat relevant, quite relevant, and highly relevant.
1.3 Inter-Rater Agreement
The Inter-Rater Agreement (IRA) is used to examine the observed agreement between experts participating in the study in terms of relevancy or clarity of questions . The assessment of IRA is performed in two different ways, conservative and less conservative. For the conservative approach, the number of items that all experts rated as “quite appropriate” or “appropriate” was divided by the total number of items. For the less-conservative approach, the number of items that the majority of experts (80%) rated as “quite appropriate” or “appropriate” was divided by the total number of items. The acceptable level of agreement was presented as 70%-80% .
1.4 Item Content Validity Index
This index rates the relevancy, clarity, and simplicity of each item [27, 26]. To obtain this index, the number of experts judging each item as relevant or clear (rated as quite relevant or highly relevant) was divided by the total number of experts. Returned values range from zero to one; when the item content validity index (I-CVI) is more than 0.79 the item is relevant, when it is between 0.70 and 0.79 it needs revision, and if the value is below 0.70, the item is eliminated.
1.5 Scale Content Validity Index
There are two methods used to assess the relevancy and clarity of the instrument: total agreement and mean approach. In the mean approach, for estimation of the relevancy (or clarity), first not relevant and quite relevant items were combined to make up a “not relevant” option, and relevant and totally relevant items were combined to form a “relevant” option. Then relevancy was calculated by dividing the number of experts that opted for relevance by the total number of experts. In different references, the minimum acceptable scale content validity index (S-CVI) for a new instrument is considered 80% .
The last step of measuring the content validity is comprehensiveness which is the ability of the instrument in covering all dimensions of the subject and evaluates whether the instrument items and their dimensions are complete samples of the intended content or not . It includes four items, incomplete, somewhat comprehensive, comprehensive, and totally comprehensive. The overall comprehensiveness of the instrument was calculated by dividing the number of experts who identified the instrument comprehensiveness as favorable to the total number of experts. A comprehensiveness score of more than 70% is acceptable.
Reliability is the degree to which the research method produces stable and consistent results under the same method and circumstance over time . We used Cronbach’s alpha to determine the internal consistency, and the Test-Retest method for reliability. Since in this study, all items (questions) were related to one area, then only one Cronbach’s Alpha index was estimated for the instrument. In internal consistency evaluation, the desired value for Cronbach’s Alpha is 0.7 or higher. To evaluate the reliability of the instrument, questions were given to a group of 36 people at two different times with 2 to 3 weeks intervals under the same circumstance, and obtained scores were used to measure the reliability by using the intraclass correlation coefficient (ICC). Reliability above 0.7 is desirable.
1.8 Study Design
After designing a valid and reliable questionnaire, a descriptive-analytical and cross-sectional study was carried out on women who attended the Breast Clinic of Arash Women’s Hospital from August 1st to October 31st, 2020. The inclusion criteria of the study were: age 18 years or above, willingness to participate, no suspicious breast lesion in clinical breast exam, no suspicious breast lesion in breast ultrasound when needed, and breast ultrasound when this imaging modality was needed for the assessment of the breast of the woman, and the absence of any suspicious lesion in mammography during the past year in women over 40 years of age. Exclusion criteria consisted of a history of breast cancer, diagnosis of a benign breast lesion except for fibrocystic changes or small (less than 1 centimeter) fibroadenomas, history of cosmetic breast surgery, a new change in the breast exam or imaging in the recent last exam, history of psychological disease, or use of psychotropic medications. After providing written informed consent from the eligible women, 350 women were entered into the study. Sampling was done in a full-census manner and all eligible participants were selected to fill out the questionnaire. Each question (item) included five-choice options; always (almost always), usually, sometimes, rarely, and never; which were given one to five scores, respectively. The overall calculated raw score for each participant was between 14 and 70.
1.9 Statistical Analysis
Statistical analyses were conducted using SPSS V.26. The calculated mean score of BH was considered as a dependent variable and age, parity, lactation, menopausal status, miscarriage, history of benign breast disease in oneself or family members, and history of benign breast surgery were independent variables. Descriptive statistics (mean, standard deviation, frequency, and percent) were used to assess the status of variables. To evaluate the effect of independent variables on the mean BH, Student T-Test (Man-Whitney for non-parametric), correlation (Spearman) and regression were conducted.