This study was performed with a mixed-methods sequential exploratory design in 2016 in Sanandaj. The first phase of the study, the qualitative part, was performed via directed content analysis within the framework of the four principles of the social marketing model. To identify the components of the social marketing-based intervention (which product, what price, where, and which promotion method), the perspectives and opinions of the study groups were required to be evaluated. The participants comprised of 50 married women aged 18 - 50 years visiting four healthcare centers of Sanandaj City. They were selected through the purposive sampling method. They participated in the study voluntarily and signed an informed consent form. Interviews were continued until reaching data saturation to ensure the adequacy of the study samples. Interviews were conducted by the first author who is a qualitative researcher in four healthcare centers. The required data were collected by semi-structured questionnaires using group discussion and deep personal interviews in the framework of social marketing model.
Data were gathered during eight individual interviews and five group discussion sessions with a minimum of six and maximum of 10 participants in each group. Considering the conditions of the interviews, group discussions lasted 1 - 2 hours and individual interviews took 1 - 1.5 hours. The interviews were initiated by asking general questions based on the constructs of the model. For example, how do you define a healthy diet? or what do you do to have a healthy diet? Then, deeper follow-up questions in line with the research objectives were asked, such as what are the benefits of a healthy diet?, who is responsible for your healthy diet?, what are the barriers to a healthy diet?, what factors facilitate a healthy diet?, and where and how do you prefer to obtain more information about eating habits?
Having collected the data, directed or theory-oriented content analysis was carried out (Shannon Hsieh, 2005). In directed content analysis, the primary codes originate from a theory or the findings of similar studies. This kind of analysis aims to validate or develop a conceptual framework or a former theory. Operational definitions for each category were determined by the given model. At the end of each session, the interview content was transcribed verbatim. In order to make a general sense of the interview as well as to immerse in the data, the researcher listened to the interview and read the transcription several times to gain a deep and correct understanding of the data. Then, encoding (converting the meaning units to shorter statements that manifested the intended concept) was performed and the obtained codes were reviewed to determine the similarities and differences, to combine the similar codes, and to make subcategories. Next, the subcategories were classified according to similarity, fitness and difference, and categories were extracted. Finally, categories, subcategories, codes, and data were reviewed and major themes of the study, social marketing constructs were extracted.
MAXQDA-10 software was used for grouping, encoding, and classification of the texts obtained from the interviews. To test the validity and reliability of the qualitative data, prolonged engagement in the field helped to establish some trust and rapport with the participants and to provide an opportunity to collect data. To make sure that the analysis reveals perspectives and opinions of the study groups, member checking was performed during data collection, and if needed, some changes were made. To confirm dependability and conformability of the data, the interviews and results of the analyses, including, the initial codes, subcategories and the categories of social marketing model, were audited by the external check method using two authors (the first and second author) expert in health education and familiar with social marketing model. Maximum variation of sampling also confirmed the conformability and credibility of the data. Sampling strategies allowed for maximum variation to occur and a vast range of views and perspectives to be considered (Polite and Hunger, 1999).
Based on the concepts obtained from the qualitative study, two questionnaires were extracted: nutritional literacy scale with a public health approach and eating behavior questionnaire. The nutritional literacy scale included 23 multiple-choice items. It was structured based on Harvard Healthy Food Pyramid. The questionnaire’s questions measured individual nutrition literacy. In addition, they measured the dimensions of access to nutrition and social support both of which are regarded as the main indicators of health literacy. Although the available tools measure health literacy based on clinical and therapeutic viewpoints, the present research explores health literacy from the viewpoint of health promotion and public health. Furthermore, the present research, investigates broader dimensions such as individuals’ lifestyles and informed decisions. The eating behavior questionnaire was based on the social marketing constructs and comprised of 53 items scored based on five-point Likert scale ranging from 1 to 5, “completely agree” to “completely disagree”. The validity of the nutrition literacy questionnaire was 0.7 and the results of R-test were as follows (P = 0.012, r = 0.75). The validity and Cronbach’s alpha reliability of the nutrition behavior questionnaire were 0.8 and 0.78, respectively. The questionnaire was given to 14 experts in the field to be evaluated.
The reliability of the nutritional literacy scale was evaluated by the test-retest method and the reliability of the dietary behavior questionnaire was confirmed by the Spearman Brown formula, which was found to be larger than 7.0 for all indices. The quantitative phase of the study was an experimental trial with a control group. The sample size of the current study was calculated to be 752 participants. The study population comprised of married women aged 18 - 50 years under the supervision of four healthcare centers in Sanandaj City, Iran. The inclusion criteria were as follows: physical and psychological readiness, ability to participate in the study, and age between 18 and 50. Lack of desire to participate in the study, significant psychological problems, and hearing loss were set as the exclusion criteria. The participants were allocated to the intervention and control groups using the randomized block method. In this method, blocks with six sub-groups were used. Among 15 possible cases and by using random number table, 63 blocks were selected. Then, based on the order of blocks, the subjects were placed in the intervention and control groups. The process continued until it reached the sample size of 376 individuals. Regarding the blinding method, the subjects and the statistical processors were not aware of their group allocations. The components of nutritional literacy interventions were designed according to the concepts extracted from the qualitative study. Intervention activities were carried out based on the healthy nutrition pyramid (Harvard). Such activities were applied to the social marketing model which itself includes a chain of five stages: planning, determining messages and posts, testing, implementation and evaluation.
The First Stage: In order to identify the intervention components based on social marketing (which product, what price, where and which promotion method), it was required to obtain the viewpoints of the target group. Collecting the essential data for this analysis, the research was carried out based on a developmental study. The research included a qualitative study of continuous exploration type and a content analysis method. The nutrition literacy interventions were planned based on the demands of women who are customers of social marketing themselves. The duration of formal educational sessions for the intervention group was three months. The aforementioned sessions were held twice a week and at least for two hours. Since the acquisition of nutritional skills is required for improving nutritional literacy, techniques such as discussion in small groups, brainstorming, role-play and play were employed. Regarding healthy nutrition, health literacy promotion interventions were conducted based on applicable and available cases. The contents of educational interventions included familiarity with Harvard’s food pyramid, its levels, the main characteristics and differences between Harvard’s healthy pyramid and the pyramid of USDA, familiarity with all kinds of whole grains, their cooking and use, the role of whole grains in health, familiarity with the role and importance of fruits and vegetables consumption, familiarity with the way to use proteins correctly, emphasis on increasing the consumption of plant proteins, and decreasing consumption of red meat. At the end of each session, practical recommendations and healthy nutritional skills were explained. The control group received only the routine nutritional education which were offered in health centers. The obtained data were analyzed by SPSS software using chi-square test, paired
t-test, independent
t-test, Pearson correlation coefficient, and ANOVA test. Flowchart of the phase of the trial is shown in
Figure 1.
Flowchart of the phase of the trial