## 3 Results and Discussion
### Questionnaire Results  
In general, occupants were slightly satisfied with the overall comfort in their offices (mean: 4.96). The most satisfying rated parameter was Light (mean: 5.57) followed by thermal (mean: 4.78), noise (mean: 4.54) and air quality (mean: 4.43) comfort. More specifically, occupants reported general moderate overall comfort (~44%) while only 15% were fully satisfied. Privacy (60%), decoration (42%) and glare (42%) were revealed to be the most dissatisfying parameters (values 1-3 from the 7-point scale). Furthermore, occupants reported complaints about very high temperatures (36%), dry and smelly air (36% and 31%) and noise inside the building (Figure 3). In order to identify the association between IEQ parameters and overall comfort, proportional odds ordinal logistic regression analysis was applied. Results showed that the greatest OR value (OR: 2.10, \(p\) < 0.05) was found for overall temperature comfort. Similar studies also reveal that thermal environment that the most influential environmental aspect [50; 51]. The second main parameter associated with overall comfort was overall  
Figure 3: Dissatisfaction with IEQ-aspects (%). Figure 2: Occupants’ medical history. noise (OR: 1.39, \(p<0.05\)). The importance of noise satisfaction was also raised in a study conducted in public and private buildings focusing on open-plan offices [52]. Then follow the satisfaction with air quality (OR: 1.17, \(p<0.1\)) and light without statistical significance (OR: 1.03, \(p>0.1\)). Figure 4 shows the prevalence of the SBS symptoms. In general, 63% reported at least one health symptom, while the most reported health symptoms were headache (41%), dry eyes (30%) and sneezing, lethargy (16%, 15%). The least frequent were related to heart symptoms such as bradycardia (1%) and irregular heartbeats (2%); respiratory phlegm/mucus (2%); wheezing (2%); and rash or irritated skin (2%). Furthermore, if any participant reported at least one symptom that was classified in SBS group, the IAQ perception was examined for these two groups by the Mann-Whitney test. The IAQ perception of the SBS group (mean: 4.24) was significantly lower at \(p\)-value level \(<\)0.1 than in the non-SBS group (mean: 4.76). Occupants were asked to evaluate the satisfaction level of the perceived control of the IEQ parameters in their offices and then how many times per day they took an action to adjust these parameters. Perceived control of noise (mean = 3) exhibited the lowest score. On the other hand, the perceived control of light (mean = 5.3) was the highest, followed by the perceived control of shade (mean = 4.52), ventilation (mean = 4.51), and temperature (mean = 4.16). Regarding the exercise of control, there was an identifiable number of occupants who reported that they did not control the IEQ parameters. More specifically, during a working day, a percentage of up to 60% and 43% of occupants were not able to adjust the noise and shade, respectively, in their offices. In general, once per day they controlled the light levels (48%) and in the case of temperature and ventilation parameters, they preferred to adjust them several times during the day (Figure 5). In Table 2, the correlations between the exercise control and occupants' perception of control over the IEQ parameters and with their comfort satisfaction as a result of them are presented. The frequency with which employees used available controlling devices in their offices showed to have a moderate association with their control perception of ventilation and noise ([PERSON] cor. 0.424 and 0.430, respectively), while a weaker correlation appeared in shading control ([PERSON] cor. 0.248). Perceived overall comfort correlated significantly and positively with perceived control parameters and temperature control appeared to have the highest correlation ([PERSON] cor. 0.474). Controlling noise in offices remained the least affecting parameter both in noise comfort ([PERSON] cor. 0.252) as well as in overall comfort ([PERSON] cor. 0.242).