# A Review on Ergonomics in Agriculture. Part II: Mechanized Operations
## 4 Results
### Supopsis of the Methodologies, Ergonomic Interventions and Risk Factors for the Development of MSDs
Regarding the type of agricultural machine, it can be easily ascertained that out of the 32 relative journal papers, the most highly reported machine during the last decade was by far the tractor with 53.13% percentage, obviously due to its versatile usage. The second studied subject was the quad bike with 18.75%. Grass trimmer came next with 9.38%, while the handheld olive beater followed with 6.25%. Finally, for the cases of power tiller, rice plowing machine and agricultural aircraft only three papers were found, one for each of them, with the relative frequency being approximately 3.13%. The same percentage was found for a study that investigated various agricultural machines with driving seats in a rice farm. The aforementioned distribution of the agricultural machines pertaining to the 32 selected studies can be illustrated in the pie chart of Figure 7. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Ref.** & **Year** & **Country** & **Machinery** & **Part.** & **Methods** \\ \hline
[58] & 2016 & Greece & Tractor & N/A & Piezoelectric accelerometer, shock absorber; Combinations of 3 different tractors, 3 implements and 4 speeds TA, shock absorbers; 6 different track-laying tractors having identical rotrolling machine & TA, Quest; Vibration measurements were performed at the operator-seat interface with a TA in a seat pad from rubber Quest, interview; Senior farmers’ opinion about their working life quality, problems in interactions with technological innovations, risk and safety issues TA; Field tests were performed with the tractor moving on various grounds, at 2 forward speeds and tire pressures and with dissimilar tractor masses TA; Analysis of shocks transmitted from the tractor seat using statistical methods and vibration signals TA, OCRA method; 3 dissimilar electric vehicles where head has oscillating sticks TA; Examination of the differences between a single- and multi-axial suspension seat and muscle activity of the low back, shoulders and neck TA, triaxial gyroscope; Measurement of vibration exposure at the head and seat Quest, anthropometric measurement devices; Hand, leg and torque strengths were measured and compared against recommended values EMG; The lowest workload regarding the arm, wrist and forearm was determined, taking into account the elbow angle and the position of the steering column Pressure sensors; 3 different tractor seats were used during narrowing, ploughing and having TA, musculoskeletal quest; measurement of the pilots’ exposure to WBV during the flight and survey on musculoskeletal symptoms on the spine \\ \hline AMDSs: agricultural machines with driving seats; EMG: electromyography; FFT: fast Fourier transform; HATV: hand–arm transmitted vibration; HAVS: hand–arm vibration syndrome; N/A: not available; NM: Nordic musculoskeletal; OCRA: occupational repetitive action; Part.: participants; Quest: questionnaire; Ref.: reference; TA: triaxial accelerometer; WB: whole-body; WBVHS: whole-body vibration health surveillance. \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._Concerning the methodology, the number of participants ranged from 379 to 1, since some studies wanted to investigate several aspects of the sample, such as age and gender and have a reliable amount of tests, whereas others wanted to test different risk factors with one worker. Additionally, the large number of studies dealing with vibration exposure justifies the frequency of the word \"triaxial accelerometer\", which is given by the abbreviation \"TA\" in Table 2. Triaxial accelerometers offer simultaneous measurements in all directions in order to analyze the experienced vibrations. Almost half of the investigating studies (53.13%) utilized triaxial, piezoelectric and whole-body accelerometers. Furthermore, most of the selected papers incorporated special questionnaires that investigate the consequences of operating agricultural machines. Questionnaires appeared in 34.38% of the studies.