Office workers are known to be at high risk of MSDs (
42). Being in a sitting posture for long hours can develop musculoskeletal symptoms of the waist, neck, shoulders, hands, and fingers (
20,
43,
44).
Hence, the present study was conducted to identify the factors influencing sitting healthy posture among office employees. As mentioned earlier, we undertook this study according to the TDF framework, which is used primarily in healthcare settings to investigate the factors influencing clinical behavior in order to design interventions to improve public and occupational health (
45).
Identified domains were supported by at least three individual quotations. According to TDF framework, knowledge was the first domain that was questioned. It is important to note that knowledge was mentioned several times by the workers. It is the basis of an intention and whether an intention is translated into action (
46).
According to previous studies, although knowledge is necessary for taking suitable posture (
14,
47-
50), it is not sufficient for doing a behavior; thus, we discussed other determinants, like skill. As stated by Mohammadi Zeydi et al. (
50,
51), we found the importance of knowledge and skill in adapting ergonomic principles in the worksite.
Furthermore, behavior change can be influenced by the expected consequences of the target behavior. According to the health behavior goal model and social cognitive theory, perceived health costs and benefits and also perceived emotional costs and benefits are core parts of outcome expectancy. Cognitive, emotional, and behavioral outcomes related to the future are classified into this domain.
Participants frequently referred to the health benefits of healthy sitting posture. Also, they mentioned that an upright sitting posture increases their self-esteem (
52). For changing behavior, a person must consider that his current behavior will have a negative effect on his health, and changing it has health benefits (
33), which is consistent with previous findings (
53).
Current health problems and treatment intensity may also be related to psychosocial factors (
54). Attitudinal influences arise from the provision of information by the schools, mass media, religion, and other people. People obtain information on health and health-related behavior, shaping their health-related knowledge, and health-related values, which along with expectations about the consequences of health-related behavior and evaluations of consequences shape attitudes towards health-related behavior contribute to making decisions about engaging in health-related behavior (
33). Also, according to the theory of social change and the theory of triadic influence, social influences are effective in changing behavior.
The emotion was another factor mentioned by the workers. In this study, positive and negative effects and also anxiety were highlighted frequently. Previous studies have revealed that job burnout and emotional fatigue, and safe climate at the workplace were the most important determinants in the incidence of work -related MSDs (
55-
57). Also, studies have confirmed that an upright sitting posture compared with a slumped posture may result in less negative and more positive emotions (
52), maintaining self-esteem, and reducing negative and increasing positive mood (
52). Negative emotional states are associated with a stooped body posture (
41,
58-
60). Prior studies have suggested significant associations between MSD complaints and physical (
61-) and psychosocial (
64-
67) factors of the work environment. Materials and resources were other barriers that frequently were mentioned in the interviews. This factor was widely discussed in the TDF framework; thus, we discuss it in detail. Workplace stressors named psychosocial factors are among the most important components affecting the health and safety of a workplace (
68). Perceived barriers as one of core constructs of the transtheoretical model (TTM) in the resource category include the lack of ergonomic furniture, organizational atmosphere, environmental stressors, and environmental barriers. In some studies, using proper furniture along with education has been found to decrease the intensity of MSDs (
48,
69).
In some studies, psychological factors have been mentioned as risk factors for work-related musculoskeletal disorders (WRMDs) (
70,
71); for example, work stress not only causes backward posture but also leads to WRMDs (
72). In addition, the management of the organization, especially its workers with a high level of responsibilities, has an important role in leading workers toward having healthy behavior. The manager acts as a model in the worksite so that he/she can boost workers' healthy behavior. Health-promoting leadership can affect employees’ health, which can also be achieved by changing working conditions. Thus, managers are responsible for the employee’s health (
73).
According to the theory of the triadic influence model and health action process approach model, self-efficacy has a crucial effect on doing a behavior. This term is the fourth component in TDF as beliefs about ability. Self-efficacy has been reported in many theories, such as self-efficacy theory, health belief model, health promotion model, I-change model. Several studies have shown that perceptions of a person’s ability to do a targeted behavior is an important factor in doing that behavior (
74,
75) and increasing self-efficacy, which leads to overcoming barriers for doing the behavior (
76). It seems that perceived self-efficacy can be helpful for designing educational programs aimed at improving proper posture among clerks. Some participants declared that taking a healthy posture is difficult for them to show perceived behavioral control among employees. According to the theory of planned behavior (TPB), individuals have different beliefs about behavior, ranging from easy to difficult. The employee’s beliefs can affect the perception of the advantages of having proper posture and evaluation of the outcomes of improper posture along with perceived beliefs about effectual feasibility of the behavior regardless of existing environmental obstacles and having confidence about the ability for having suitable posture (
23). Behavioral control is considered as being able to perform a specific type of behavior. Consistent with our study, perceived behavioral control in some previous studies has been mentioned as a strong predictor of behavior (
77,
78). Also, there is a direct relationship between taking proper posture and perceived behavioral control (
79). However, Abedi et al. (
80), in a study, found no relationship between these two factors.
The goal was another category that was discussed by the participants. Interviewees said that in some cases, they do not consider a priority for this behavior against health problems. When the targeted change is compatible with a person’s personal goal structure, the health behavior change is most probable to happen as mentioned in the health behavior goal model. Besides, the personal goal structure consists of higher-order goals. Higher-order goals include goals related to health (e.g. to stay healthy), wellbeing (e.g. to enjoy life to the fullest), personal growth (e.g. to develop talents), and social goals (e.g. to be a good father) (
33). The effects of goal in behavior change in different fields have been mentioned (
81-
83).
As explained in the TDF definition, memory shapes other parts of this framework. In response to interview questions, most participants stated that cognitive fatigue and attention are remarkable elements in taking a healthy posture. For cognitive control, inhibition can be conceptualized as a procedure that blockes the extension of activation and maintenance of the focus on the task at hand (
84). Among postures, various levels of autonomic activation provide differences in mental fatigue (
85). Exhaustion of (bodily or mental) resources may cause fatigue while carrying out a task (
86). In general, evidence suggests that individuals become more tired (
87-
89) and fall asleep earlier (
90) when they are in a lying position compared with an upright posture.
TTM was developed to describe behavioral intention. As some participants declared that they think about changing this behavior, but they postpone it, we used this category for describing this statement. Furthermore, behavioral intention is the most important determinant of individual behavior, according to TPB (
80). Abedi et al. (
80) introduced behavioral intention as the only predictor of taking correct posture among the nurses. There was a significant link between the constructs of TPB and MSDs among the nurses so that when people with a history of MSD in each organ were compared with people who did not have this problem, they showed lower levels of subjective norm, attitude, perceived behavioral control, and behavioral intention for taking correct body positions at work (
91).
The probability of carrying out an action is determined by three factors: (1) Strengthening of the good habits for carrying out the action (reflected by the time spent by a person who has previously performed that task); (2) strengthening of behavioral intention to carry out the action; and (3) the existence of conditions facilitating the performance of the action. The probability of carrying out an action is proportional to the strengthening of good habits and intention. Also, self-monitoring in this category is a process involving self-observation and self-control to maintain an appropriate behavior (
33). Lenzen et al. (
92) stated that nearly half of the studies (47%) have revealed a theoretical structure for action planning as a crucial factor in behavioral regulation. Behavior change theories are the most common frameworks for goal setting or action planning to change a person’s behavior. Nearly 24% of studies reported self-efficacy -one of the constructs of the Social Cognitive theory (
93), - as a key concept for setting goals (
94) Using these theories can overcome the intention-behavior gap and barriers to behavior change. Self-Regulation theory, Proactive Coping theory, Health Action Process approach, Self-Determination theory, and TPB other behavioral change theories. These theories were reported to be used because of their focus on bridging the intention-behavior gap and barriers to behavior change. In the present study, 11 domains of the TDF were identified as determinants. In each study, depending on the type of behavior, different domains of the TDF have been selected. In line with our study, in a qualitative study on TDF aimed to investigate barriers and facilitators to breaking up and reducing sitting time, 11 domains related to this behavior were identified (
95).
5.1. Conclusions
The results of the present study indicated that taking a healthy sitting posture in employees is a multi-level factor. Also, effective comprehensive interventions are needed to target determinants of doing a behavior at the individual, interpersonal, and organizational levels. Through adopting a theory-based approach, we identified 12 determinants to taking proper sitting posture among office workers. TDF was designed as a theoretical lens to observe the cognitive, emotional, environmental effects on behavior. Its domains are derived from a large number of theories of behavior change. Behavior change requires an understanding of the effects of behavior on the context, in which behavior occurs.
5.2. Strengths and Limitations
The present study was a first attempt to understand determinants of proper sitting posture based on TDF. In this study, only Iranian office workers were included as the study sample. Factors discouraging proper posture may vary between other countries.