# Work-Related Health Disorders among Saudi Computer Users

Authors: Ibrahim M. Jomoah
Journal: The Scientific World Journal
 (2014)

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## Abstract

The present study was conducted to investigate the prevalence of musculoskeletal disorders and eye and vision complaints among the computer users of King Abdulaziz University (KAU), Saudi Arabian Airlines (SAUDIA), and Saudi Telecom Company (STC). Stratified random samples of the work stations and operators at each of the studied institutions were selected and the ergonomics of the work stations were assessed and the operators’ health complaints were investigated. The average ergonomic score of the studied work station at STC, KAU, and SAUDIA was 81.5%, 73.3%, and 70.3, respectively. Most of the examined operators use computers daily for ≤ 7 hours, yet they had some average incidences of general complaints (e.g., headache, body fatigue, and lack of concentration) and relatively high level of incidences of eye and vision complaints and musculoskeletal complaints. The incidences of the complaints have been found to increase with the (a) decrease in work station ergonomic score, (b) progress of age and duration of employment, (c) smoking, (d) use of computers, (e) lack of work satisfaction, and (f) history of operators’ previous ailments. It has been recommended to improve the ergonomics of the work stations, set up training programs, and conduct preplacement and periodical examinations for operators.


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## Body

## 1. Introduction

The one thing that has had the greatest impact on our lives in modern time is the computer. Along with smaller size and affordable prices, there has been the advent of the Internet. This has ensured that people use this technology either at their work place or at home. Meanwhile, the applications of computer technology and the accompanying use of video display terminals (VDTs) are revolutionizing the workplaces worldwide, and their use will continue to grow in the future.Although these developments may perform operators’ tasks efficiently, they could face some factors such as work stress, repetitious tasks, boredom, interpersonal factors, unsafe postures, and poor design of workstation that will negatively affect their health, performance, and productivity. For example, the development of VDTs technology may have contributed to the increase of users’ health problems such as cumulative trauma disorders (CTDs) of upper extremity and back pain [1–54] as well as vision problems [1–11, 13, 14, 19, 20, 26, 44, 45, 51–53, 55–84].However, the application of ergonomics principles to office workstations will reduce such health risks. For example, one of the goals of the ergonomic processes is to design or modify people’s work and other activities to be within their capabilities and limitations [3, 5–7, 12, 15–17, 22, 23, 28–30, 38, 44–46, 85–88]. One possible outcome of poor harmonization is disorder of the musculoskeletal system known as repetitive strain injuries (RSI), CTD, or activity and work-related musculoskeletal disorder (WMSD). Those working in office-type jobs involving keyboarding and other computer related activities suffer from these disorders [9, 13, 15–18, 22–24, 28, 33, 42, 50, 88].Currently computer related injuries are developing into an epidemic among computer users. It is estimated that, worldwide, 25% of computer users are already suffering from computer related injuries [35]. The United States has to shell out more than 2 billion US dollars annually for having ignored these computer related problems. It is now proved that the duration of work and computer-related problems are positively correlated. It is not uncommon these days for people having to leave computer dependent careers or even be permanently disabled and unable to perform tasks such as driving or dressing themselves. Occupationally caused RSI rank first among the health problems potentially affecting the quality of life [89]. Meanwhile, poor workstation design and poor ergonomics have been associated with an increased risk of developing these disorders.The tremendous use of computer by the staff members, technicians, and students at King Abdulaziz University (KAU), by our experience, has been accompanied by increase in the number of attendances to University Medical Directorate (Services) with general, eye and vision, and musculoskeletal complaints. When this observation was brought to the attention of KAU officials, they urged and encouraged concerned personnel to study the nature of this problem and propose remedial actions.Meanwhile, one of the first institutions that had applied computer technology in Saudi Arabia was the Saudi Airlines tickets’ reservation offices (SAUDIA). It is considered to be one of most eligible areas to conduct a study regarding VDT health related problems. Putting this in mind, KAU urged concerned personnel to include it in the present study. Also, the Saudi Telecom Company (STC) works in Jeddah comprises nearly 430 VDT workstations where 360 operators and mostly 70 supervisors work for whole shifts. There have been some claims that these operators and supervisors suffer some general musculoskeletal and eye and vision complaints. Consequently, these works have been decided to be included in this study.The objectives of the present study were(1)
to evaluate the magnitude of the problem of inconveniences in the use of computers in KAU, SAUDIA, and STC, as well as the inconveniences in the computers’ workstations,(2)
to investigate computers’ operators health complaints,(3)
to investigate environmental and behavioral factors contributing to the occurrence of the complaints,(4)
to propose remedial actions that might contribute to reducing these complaints.


## 2. Methodology

### 2.1. Study Population

Inventories of the computer workstations and operators in the different colleges and units of KAU, in the different departments and units of SAUDIA tickets’ reservation offices, and in the different departments and units of STC head office in Jeddah had, primarily, been conducted to assess the magnitude of computer use there. The findings of the inventories are summarized in Table1.Table 1
Existing computer workstations and operators in the different units of KAU, SAUDIA, and STC and the sample selected for the study.
Institution
Units
Existing service
Sample
Workstation
Supervisor
Operator
Workstation
Supervisor
Operator
KingAbdulazizUniversity(KAU)
(i) Higher administration, includingDeanship of Admission andRegistration and Deanship ofStudent Affairs
301
14
(ii) Deanship of InformationTechnology
114
16
(iii) Deanship of Library Affairs
73
(iv) Faculty of Economics andAdministration
96
9
(v) Faculty of Sciences
86
9
(vi) Faculty of Engineering
130
16
(vii) Faculty of Medicine and University Hospital
34
17
(viii) Faculty of Arts and Humanities
81
14
(ix) Faculty of Earth Sciences
63
5
(x) Faculty of Environmental Designs
41
(xi) Faculty of Marine Sciences
8
(xii) Faculty of Meteorology,Environment and Arid Land Agriculture
16
Total
1043
100
Saudi AirlinesTicketReservation(SAUDIA)
(i) Central Control for Africa and Europe Flights
20
15
(ii) Central Control for Local and Gulf Flights
20
15
(iii) Central Control for Asia and Middle East Flights
10
5
(iv) Record and Follow-up Department
20
10
(v) Customer Services Department
165
55
Total
235
100
Saudi TelecomCompany(STC)
(i) English Call Services Department
15
90
4
16
(ii) Help Services Department
24
120
8
27
(iii) Other Services Department
30
150
10
35
Total
69
360
22
78Representative random samples of 100 workstations, and operators (all males, since no females are employed there), were selected from each of the three institutions, considering that the selection of the sampled stations and operators had been affected by the readiness of the individual administrations and operators in the different departments and units to participate in the study. The selected stations are also presented in Table1.


### 2.2. Studying Ergonomics of Workstations

A study form entitled “Ergonomics Rating of Computer Applications” was developed to assess the ergonomics status of the studied computer workstations. The form was designed after reviewing the ANS/HFES Committee document [6], and many computer’s workstation evaluation checklists that had been tested and used by international institutions include(1)
U.S. Department of Health and Human Services, Centers of Disease Control, and Prevention (CDC), Evaluation Checklist;(2)
National Institute for Occupation Safety and Health (NIOSH) Ergonomics Work-Place Evaluations of Musculoskeletal Disorders Checklist;(3)
U.S. Department of Labor, Occupational Safety, and Health Agency (OSHA) Computer Workstation Ergonomic Checklist;(4)
University of California Computer Workstation Self-Evaluation Checklist;(5)
California State University Ergonomics Evaluation Checklist;(6)
Cornell University Ergonomics Checklist;(7)
University of Virginia Library Ergonomics Evaluation Form;(8)
Institute for Occupational Physiology at the University of Dortmund Checklist for Computer Workstation;(9)
Atlantic Mutual Centennial Insurance Company Workstation Checklist.The ergonomics score for the evaluation of the workstation is 43, distributed by the different components. Each component has certain number of scores, determining the maximum score of the component as shown in Table2. Besides, 3 scores are allowed for the work organization and 4 scores for the training and provision of information, making a total score for the work at the specific workstation of 50, which is equivalent to 100% when scoring percentagewise.Table 2
Distribution of the ergonomics scores of the different components of the studied workstations.
Workstation component
Maximum score
(1) Desk
5
(2) Seat
6
(3) Footrest
1
(4) Display screen
8
(5) Keyboard
3
(6) Mouse
3
(7) Document holder
2
(8) Space and room layout
7
(9) Task and posture
2
(10) Illumination
4
(11) Noise and thermal environment
2
Total scores
43Each score item is clearly presented to be answered by “Yes” or “No” to avoid any personal differences or any bias by the evaluators. The “Yes” answers are counted to represent the score out of 50, and some ten stations were evaluated to test the study from and found to be satisfactory for the conduct of the study. Furthermore, the evaluation of the workstations was carried out, only, by the authors for quality assurance of the data collection. The study form has been designed in four major sections including the following.Section (1). It includes basic information of investigated organizations (colleges/units), particularly as related to presented services.Section (2). It includes ergonomics rating of investigated workstations by checking the details of each component of the work place, including(1)
desk, as related to space of desk top, layout of the desk, top equipment, desk top and distance from operator’s eye, and existence of comfortable resting facility for operators’ hands and rest;(2)
seat, as related to dimensions, casters, operators’ leg clearance, armrests, back rest, seat cushion, and seat comfort ability and stability;(3)
footrest, as related to need, availability, and status of footrest;(4)
display screen, as related to location, height and tilting of the monitor, distance from operator’s eye, freedom of screen from glare and reflection, stability of image and freedom from flickering, ease to read characters, and possibility of adjusting screen brightness and contrast;(5)
keyboard, as related to dimensions, location with reference to operator’s hands and elbows, and exchanging operation between keyboard and mouse without operator’s hand extension or twisting wrist;(6)
mouse, as related to its location with reference to operator smooth running and operator’s awareness of its details of operation and maintenance;(7)
document holder, as related to need, availability, and status of the document holder;(8)
space and room layout, as related to adequate access to work place, availability of space to maneuver the seat, work correct posture, availability of adequate space for equipment needed for work, location of monitor with reference to windows, freedom of work area from obstructions, and hazards of tripping and neatness of the work area;(9)
task and posture, as related to freedom of operator’s hands from phone while typing and resting his hand wrists;(10)
illumination, as related to level of lighting, status of luminaries and illumination fixtures, use of blinds on windows, and background of the screen with surrounding environment;(11)
noise and thermal environment, as related to level of quietness and status of air conditioning in work area.Section (3). It includes work organization rating, by investigating work organization, work hours, rest pauses and noncomputer work assignment, and work load.Section (4). It includes training and provision of information, by investigating operator’s on-the-job and formal training, certainty of his use of software, keying habits, operator’s capability of control of his workstation and work environment, and operator’s adoption of good posture and avoiding visual fatigue at work.


### 2.3. Investigating Operators’ Health Symptoms

A study form entitled “Impact of Computer Use on Operators” was developed to evaluate the effect of computer use on operator’s health as reviewed and/or recommended by the NIOSH [1], WHO [5], and ANSI/HFES [6]. It is divided into four main sections as follows.Section (1). It includes basic data, including name, gender, address, workstation, age, education, and smoking habit.Section (2). It includes work data, including work type, duration of employment, formal training, work speed, daily hours of computer use, nature of computer use (continuous or intermittent), and work satisfaction.Section (3). It includes health disorders before present work, including previous ailments or complaints of the musculoskeletal system and complaints of the eye and vision.Section (4). It includes current symptoms, including the general complaints and their frequency, the eye and vision symptoms and their frequency, the maximum work hours before their occurrence and the time required for their release, and the musculoskeletal disorders and their location, description, frequency, and persistence, as well as the approached medical treatment and the sickness absenteeism as related to the work-related ailments.


### 2.4. Data Analysis

The collected data were visually inspected for fliers, then introduced into PC, and subjected to statistical analysis using Microsoft Excel 2007.


## 2.1. Study Population

Inventories of the computer workstations and operators in the different colleges and units of KAU, in the different departments and units of SAUDIA tickets’ reservation offices, and in the different departments and units of STC head office in Jeddah had, primarily, been conducted to assess the magnitude of computer use there. The findings of the inventories are summarized in Table1.Table 1
Existing computer workstations and operators in the different units of KAU, SAUDIA, and STC and the sample selected for the study.
Institution
Units
Existing service
Sample
Workstation
Supervisor
Operator
Workstation
Supervisor
Operator
KingAbdulazizUniversity(KAU)
(i) Higher administration, includingDeanship of Admission andRegistration and Deanship ofStudent Affairs
301
14
(ii) Deanship of InformationTechnology
114
16
(iii) Deanship of Library Affairs
73
(iv) Faculty of Economics andAdministration
96
9
(v) Faculty of Sciences
86
9
(vi) Faculty of Engineering
130
16
(vii) Faculty of Medicine and University Hospital
34
17
(viii) Faculty of Arts and Humanities
81
14
(ix) Faculty of Earth Sciences
63
5
(x) Faculty of Environmental Designs
41
(xi) Faculty of Marine Sciences
8
(xii) Faculty of Meteorology,Environment and Arid Land Agriculture
16
Total
1043
100
Saudi AirlinesTicketReservation(SAUDIA)
(i) Central Control for Africa and Europe Flights
20
15
(ii) Central Control for Local and Gulf Flights
20
15
(iii) Central Control for Asia and Middle East Flights
10
5
(iv) Record and Follow-up Department
20
10
(v) Customer Services Department
165
55
Total
235
100
Saudi TelecomCompany(STC)
(i) English Call Services Department
15
90
4
16
(ii) Help Services Department
24
120
8
27
(iii) Other Services Department
30
150
10
35
Total
69
360
22
78Representative random samples of 100 workstations, and operators (all males, since no females are employed there), were selected from each of the three institutions, considering that the selection of the sampled stations and operators had been affected by the readiness of the individual administrations and operators in the different departments and units to participate in the study. The selected stations are also presented in Table1.


## 2.2. Studying Ergonomics of Workstations

A study form entitled “Ergonomics Rating of Computer Applications” was developed to assess the ergonomics status of the studied computer workstations. The form was designed after reviewing the ANS/HFES Committee document [6], and many computer’s workstation evaluation checklists that had been tested and used by international institutions include(1)
U.S. Department of Health and Human Services, Centers of Disease Control, and Prevention (CDC), Evaluation Checklist;(2)
National Institute for Occupation Safety and Health (NIOSH) Ergonomics Work-Place Evaluations of Musculoskeletal Disorders Checklist;(3)
U.S. Department of Labor, Occupational Safety, and Health Agency (OSHA) Computer Workstation Ergonomic Checklist;(4)
University of California Computer Workstation Self-Evaluation Checklist;(5)
California State University Ergonomics Evaluation Checklist;(6)
Cornell University Ergonomics Checklist;(7)
University of Virginia Library Ergonomics Evaluation Form;(8)
Institute for Occupational Physiology at the University of Dortmund Checklist for Computer Workstation;(9)
Atlantic Mutual Centennial Insurance Company Workstation Checklist.The ergonomics score for the evaluation of the workstation is 43, distributed by the different components. Each component has certain number of scores, determining the maximum score of the component as shown in Table2. Besides, 3 scores are allowed for the work organization and 4 scores for the training and provision of information, making a total score for the work at the specific workstation of 50, which is equivalent to 100% when scoring percentagewise.Table 2
Distribution of the ergonomics scores of the different components of the studied workstations.
Workstation component
Maximum score
(1) Desk
5
(2) Seat
6
(3) Footrest
1
(4) Display screen
8
(5) Keyboard
3
(6) Mouse
3
(7) Document holder
2
(8) Space and room layout
7
(9) Task and posture
2
(10) Illumination
4
(11) Noise and thermal environment
2
Total scores
43Each score item is clearly presented to be answered by “Yes” or “No” to avoid any personal differences or any bias by the evaluators. The “Yes” answers are counted to represent the score out of 50, and some ten stations were evaluated to test the study from and found to be satisfactory for the conduct of the study. Furthermore, the evaluation of the workstations was carried out, only, by the authors for quality assurance of the data collection. The study form has been designed in four major sections including the following.Section (1). It includes basic information of investigated organizations (colleges/units), particularly as related to presented services.Section (2). It includes ergonomics rating of investigated workstations by checking the details of each component of the work place, including(1)
desk, as related to space of desk top, layout of the desk, top equipment, desk top and distance from operator’s eye, and existence of comfortable resting facility for operators’ hands and rest;(2)
seat, as related to dimensions, casters, operators’ leg clearance, armrests, back rest, seat cushion, and seat comfort ability and stability;(3)
footrest, as related to need, availability, and status of footrest;(4)
display screen, as related to location, height and tilting of the monitor, distance from operator’s eye, freedom of screen from glare and reflection, stability of image and freedom from flickering, ease to read characters, and possibility of adjusting screen brightness and contrast;(5)
keyboard, as related to dimensions, location with reference to operator’s hands and elbows, and exchanging operation between keyboard and mouse without operator’s hand extension or twisting wrist;(6)
mouse, as related to its location with reference to operator smooth running and operator’s awareness of its details of operation and maintenance;(7)
document holder, as related to need, availability, and status of the document holder;(8)
space and room layout, as related to adequate access to work place, availability of space to maneuver the seat, work correct posture, availability of adequate space for equipment needed for work, location of monitor with reference to windows, freedom of work area from obstructions, and hazards of tripping and neatness of the work area;(9)
task and posture, as related to freedom of operator’s hands from phone while typing and resting his hand wrists;(10)
illumination, as related to level of lighting, status of luminaries and illumination fixtures, use of blinds on windows, and background of the screen with surrounding environment;(11)
noise and thermal environment, as related to level of quietness and status of air conditioning in work area.Section (3). It includes work organization rating, by investigating work organization, work hours, rest pauses and noncomputer work assignment, and work load.Section (4). It includes training and provision of information, by investigating operator’s on-the-job and formal training, certainty of his use of software, keying habits, operator’s capability of control of his workstation and work environment, and operator’s adoption of good posture and avoiding visual fatigue at work.


## 2.3. Investigating Operators’ Health Symptoms

A study form entitled “Impact of Computer Use on Operators” was developed to evaluate the effect of computer use on operator’s health as reviewed and/or recommended by the NIOSH [1], WHO [5], and ANSI/HFES [6]. It is divided into four main sections as follows.Section (1). It includes basic data, including name, gender, address, workstation, age, education, and smoking habit.Section (2). It includes work data, including work type, duration of employment, formal training, work speed, daily hours of computer use, nature of computer use (continuous or intermittent), and work satisfaction.Section (3). It includes health disorders before present work, including previous ailments or complaints of the musculoskeletal system and complaints of the eye and vision.Section (4). It includes current symptoms, including the general complaints and their frequency, the eye and vision symptoms and their frequency, the maximum work hours before their occurrence and the time required for their release, and the musculoskeletal disorders and their location, description, frequency, and persistence, as well as the approached medical treatment and the sickness absenteeism as related to the work-related ailments.


## 2.4. Data Analysis

The collected data were visually inspected for fliers, then introduced into PC, and subjected to statistical analysis using Microsoft Excel 2007.


## 3. Results and Discussion

### 3.1. Ergonomics of the Workstations

The ergonomics scores of the studied workstations in the three institutions are illustrated in Table3 and Figures 1 and 2. The average workstations score in STC has been rated very good (81.5±14.34) which is considerably higher than the scores of both KAU and SAUDIA (73.3+15.13 and 70.3±13.54, resp.) (Figure 2). This might be attributed to the relatively recent establishment of the workstations in STC in comparison to the other two study locations (KAU and SAUDIA). However, the score of the different components varies considerably in the three locations. For example, task and posture has been rated 95% and 90% at STC and SAUDIA, respectively, while it has been the lowest scored component at KAU (54%). Also, work organization has been rated the second highest (98.3%) at SAUDIA while it has been rated the second lowest at KAU (57.7%) and in the middle of the scores at SAUDIA (73.2%). These variations might be attributed to the differences of the type of work and pattern of computer use at the different study locations. The distribution of the ergonomics scores of the examined workstations might be considered to follow normal model but truncated (Figure 2).Table 3
Positive ergonomics components of the examined workstations.
Number
Ergonomics components
KAU* (N = 100)
SAUDIA** (N = 100)
STC*** (N = 100)
Number of positives
Average
Number of positives
Average
Number of positives
Average
I
Noise and thermal environment
1
Quietness
75
84.0
78
81.5
83
86.5
2
Air-conditioning
93
85
90
II
Display screen
3
Monitor location
71
80.4
70
75.4
97
87.4
4
Monitor top
80
100
99
5
Monitor distance from eye
71
100
98
6
Monitor tilting
75
72
97
7
Glare and reflection
68
60
70
8
Image stability
91
67
80
9
Ease of reading
95
68
74
10
Brightness and contrast
92
66
84
III
Desk
11
Space
81
78.4
100
81.4
100
99.4
12
Layout
85
85
99
13
Distance from eye
74
86
100
14
Room for leg
93
65
100
15
Hand/wrist
59
71
98
IV
Mouse
16
Distance from hand
83
77.7
75
71.3
72
71.3
17
Run
76
78
76
18
Operator’s familiarity
74
61
66
V
Seat
19
Height
89
75.3
100
74.7
99
77.7
20
Dimensions
78
72
95
21
Armrest
76
75
77
22
Backrest
64
79
59
23
Pad (foam)
71
60
63
24
Comfort and stability
73
62
73
VI
Space and room layout
25
Adequate access
90
73.7
65
68.9
24
78.7
26
Space around seat
86
100
100
27
Layout
80
61
93
28
Location of equipment
62
61
88
29
Monitors’ positions
51
66
100
30
Obstructions and hazards
75
60
100
31
Housekeeping
72
69
46
VII
Illumination
32
Lighting level
91
72.3
55
48.8
60
86.8
33
Luminaries
66
46
99
34
Effectiveness
61
43
97
35
Background behind screens
71
51
91
VIII
Training and provision of information
36
Use of software
75
71.5
46
47.3
76
60.3
37
Habit keying
73
59
66
38
Adjustment
74
43
65
39
Good posture and visual fatigue
64
41
34
IX
Keyboard
40
Distance
69
69.7
66
66.0
98
95.0
41
Width
73
69
75
42
Height and key angle
67
63
92
X
Footrest
43
Compression of thigh
68
68.0
65
65.0
54
54.0
XI
Document holder
44
Need
64
63.0
90
90.0
39
38.0
45
Balance of head posture
62
90
37
XII
Work organization rating
46
Breaks
79
59.7
100
73.3
88
89.3
47
Urgent peaks  and  interruptions
40
55
83
48
Over time
60
65
97
XIII
Task and posture
49
Phoning while typing
33
54.0
90
95.0
99
90.0
50
Typing posture
75
100
81
Total average score
72.3
71.1
81.0
*KAU = King Abdulaziz University.
**SAUDIA = Saudi Airlines.
***STC = Saudi Telecom Company.Figure 1
Average ergonomics scores of the examined workstation components.Figure 2
Distribution of the ergonomics scores of the examined workstation component.


### 3.2. Characteristics of the Work Population

The demographic and occupational characteristics of the studied populations of the computer users/operators in the three institutions are presented in Tables4 and 5. The populations at the different study locations were mostly young, since 98% of the subjects in both KAU and STC, and 89% at SAUDIA, were younger than 50 years. However, the subjects of the study population at SAUDIA were relatively older since 27% of them were younger than 35 years in comparison to 80% at STC and 68% at KAU (Table 4). The average ages at the KAU, SAUDIA, and STC were 31.5, 39.7, and 30.3 years, respectively. Yet 78% and 73% of the populations at STC and KAU have been employed for less than 10 years, in comparison to 23% at SAUDIA that began using VDT earlier than the other two institutions (Table 5). The average durations of employment at KAU, SAUDIA, and STC were 7.1, 19,7, and 7.4 years, respectively. Meanwhile, the levels of education among KAU and STC populations were higher than the SAUDIA population. For example, 65% and 41% of KAU and STC populations received higher education in comparison to only 23% at SAUDIA population. Also, 16% of the KAU and 5% of the STC populations, respectively, received graduate education (Doctor and/or Master), while none of the subject at SAUDIA population had such education level.Table 4
Demographic characteristics of the study population.
Demographic characteristics
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
Age (years)
20–24
24
9
19
25–29
30
8
47
30–34
14
10
14
35–39
15
18
7
40–44
10
20
8
45–49
5
24
3
50–54
2
9
2
>55
0
2
0
Education
Middle
6
2
2
Secondary (general)
21
71
55
Secondary (technical)
8
4
2
High (technical)
19
2
13
High (administrative)
30
21
23
Graduate (master + doctor)
16
0
5
Smoking index
Nonsmokers
79
76
62
<100
6
5
17
100–199
3
2
9
200–399
2
4
5
400–500
5
3
3
>600
5
10
4
Vision symptoms prior to present work*
None
58
70
58
Short-sighted
30
23
25
Long-sighted
7
2
10
Others
7
5
7
Musculoskeletal symptoms prior to present Work*
None
59
62
55
Neck pain
22
24
17
Shoulder and/or arms pain
11
11
4
Lower trunk pain
13
23
16
Thigh and leg pain
5
8
4
Others
1
1
4
*The same subject might have more than one symptom occurring at different frequencies.Table 5
Occupational characteristics of the study population.
Occupational characteristics
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
Duration of employment (years)
<1
12
7
7
1-2
23
5
24
3-4
20
4
17
5–9
18
7
30
10–14
11
7
5
15–19
7
14
9
20–24
5
20
5
25–29
3
16
3
30–34
1
16
0
≥35
0
4
0
Type of work
Data entry
22
54
33
Data acquisition
18
23
9
Typist
23
0
0
Communication task
8
20
53
Comprehensive office tasks
29
3
5
Duration of formal training (days)On-the-job training only
58
61
28
<50
12
19
24
50–99
5
8
14
100–199
11
2
20
200–299
4
2
4
300–399
4
4
1
400–499
3
0
1
≥500
3
4
8
Work speed
Fast
39
30
45
Average
56
70
49
Slow
5
0
6
Computer use (hrs/day)
3
15
0
2
4
12
0
3
5
9
0
3
6
20
100
53
7
14
0
1
8
22
0
17
9
8
0
21
Nature of daily work on computer
Continuous
61
53
85
Intermittent
39
47
15
Rest pauses of work shift (%)
5–9
10
0
12
10–14
22
0
19
15–19
18
0
16
20–24
19
0
21
25–29
9
100
10
30–34
9
0
11
35–39
7
0
6
≥40
6
0
5
Elements of work satisfaction
Satisfaction by foreman and colleagues  interrelations
100
99
99
Satisfaction by absence work stress
68
60
61
Satisfaction of work control
96
94
96
Satisfaction of job attitude
92
81
82
Satisfaction by vigilance requirement
94
100
94
Satisfaction by nature of work
73
85
55
Satisfaction by absence of repetitive work and monotony
59
34
35
Evaluation of work satisfaction*
Very satisfied
39
35
29
Satisfied
43
37
31
Satisfied to some extent
10
14
27
Not satisfied
8
14
13
*Percent of duration(s) of rest pauses to duration of work shift.Most of the study populations were nonsmokers (79%, 76%, and 62% of subjects at KAU, SAUDIA, and STC, resp.) and 26% of them at STC were light smoker (smoking index less than 200) that might be added to the proportion of the nonsmoker there to be 88%. This distribution might, however, be biased by the relatively young age of the examined subjects.Considerable proportion of the populations either had no vision problems before employment (58%, 70%, and 58% at KAU, SAUDIA, and STC, resp.), or were short-sighted (30%, 23%, and 25%, resp.), while the rest were long-sighted or had other vision problems (14%, 7%, and 17%, resp.). Similarly, more than one half of the populations at the three study locations had no musculoskeletal symptoms before employment (59% at KAU, 62% at SAUDIA, and 55% at STC), while considerable proportions of the populations had neck pain (22% at KAU, 24% at SAUDIA, and 17% at STC). The rest of the populations had such symptom at one or more body locations.More than one half of the population of KAU (52%) was either typist (23%) or involved in comprehensive office tasks (29%), while 40% of them were involved in data entry (22%) and data acquisition (22%). However, at SAUDIA, 77% of the populations were involved in data entry (54%) or data acquisition (23%) while 20% of them were involved in communication tasks and none of them was typist. Similarly, at STC, 86% of the populations were involved in communication tasks (53%) or data entry (33%), and none of them was typist. While 58% and 61% of the populations at KAU and SAUDIA, respectively, received on-the-job training only, and the rest received formal training for different periods, the opposite existed at STC, where 72% of the population received formal training for different periods, and only 28% of the population received on-the-job training only. Consequently, 61% of the populations at KAU and 70% at SAUDIA considered their work speed as average (56% and 70%, resp.) or slow (5% and 0%, resp.), while 45% of the population at STC considered their work speed as fast and 55% of them considered their work speed as either average (49%) or slow (6%).Considerable proportions of the populations at KAU and STC used computer for 7, 8, or 9 hours per day (44% and 39%), while the whole population at SAUDIA (100%), and 53% of them at STC, used computer for 6 hours. On the other hand, 36% of the operators at KAU used computer for 3, 4, or 5 hrs. per day, while none of them at SAUDIA, and 9% of them at STC, operated computers for these shorter periods. However, only 53% of the SAUDIA population operated computer continuously in comparison to 85% of the STC and 61% of KAU populations. Meanwhile, mostly 70% of KAU (69%) and STC (68%) populations had rest pauses <25% of the work shift, and 22% of the two populations got rest pauses 30%–40% of the shift, while the whole SAUDIA population had 25%–29% of their shift as rest pauses, in comparison to 9% and 10% of the other two populations.Eighty-two percent of the computer users in KAU, 72% of the operators at SAUDIA, and 60% of operators at STC were satisfied (and many were even very satisfied) at their work, particularly as related to their excellent satisfaction by their colleagues, work control, job attitude, and vigilance requirement, while the boredom from repetitive work and monotony and the work stress were the main causes of dissatisfaction among them, particularly the SAUDIA and STC populations (41%, 66%, and 65% at KAU, SAUDIA, and STC, resp.).


### 3.3. Operators’ Health Complaints

The operators’ health complaints are presented in Tables6–9. Mostly one third of the operators (35%, 33%, and 27% of KAU, SAUDIA, and STC populations, resp.) was suffering from body fatigue, while 23%, 21%, and 37% of them were suffering from headache, such complaints occurred mostly sometimes among all the populations, however occurred to less extent, particularly among SAUDIA and STC operators. The lack of concentration occurred to less extent (for example, 8%, 6%, and 20% among KAU, SAUDIA, and STC populations, resp.), particularly and daily among SAUDIA and STC populations (Table 6).Table 6
Incidence of work-related general symptoms among the examined computer users/operators.
Symptoms
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
Headache
77
17
6
0
23
79
11
6
4
21
63
25
11
1
37
General body fatigue
65
31
4
0
35
67
17
12
4
33
73
17
9
1
27
Lack of concentration
92
7
1
0
8
94
1
3
2
6
80
10
8
2
20
Total
46
45
9
0
54
60
22
12
6
40
97
1
1
1
3
*The same subject may have more than one symptom occurring at different frequencies.Table 7
Incidence of work-related eye and vision symptoms among the examined computer users/operators.
Symptoms
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
Eye
Eye discomfort
85
12
3
0
15
88
8
4
0
12
91
7
1
1
9
Aches
91
6
3
0
9
96
3
1
0
4
97
1
2
0
3
Pain
95
4
1
0
5
95
2
3
0
5
92
5
3
0
8
Redness
91
6
2
1
9
90
8
1
1
10
93
5
2
0
7
Irritation and itching
93
4
3
0
7
94
3
3
0
6
96
2
2
0
4
Burning
88
9
3
0
12
93
5
2
0
7
95
3
2
0
5
Tearing
82
14
4
0
18
92
3
4
1
8
91
7
1
1
9
Dryness
96
3
1
0
4
92
5
2
1
8
96
3
1
0
4
Vision
Blurred: close objects
92
6
2
0
8
93
3
3
1
7
95
3
2
0
5
Blurred: distant objects
88
9
3
0
12
86
8
5
1
14
91
6
3
0
9
Sensitivity to light
86
10
3
1
14
92
3
4
1
8
84
14
2
0
16
Double flickering
96
4
0
0
4
93
2
4
1
7
97
2
1
0
3
Double vision
99
1
0
0
1
94
3
2
1
6
93
4
3
0
7
Change in color perception
98
2
0
0
2
99
1
0
0
1
97
2
1
0
3
Others
98
1
1
0
2
99
0
1
0
1
0
0
0
0
0
All eye and vision symptoms
41
48
9
2
59
61
22
12
5
39
46
14
15
25
54
*The same subject may have more than one symptom occurring at different frequencies.Table 8
Incidence of work-related musculoskeletal symptoms among the examined computer users/operators.
Symptoms
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
Aching
73
18
8
1
27
84
9
6
1
16
69
20
10
1
31
Tingling
84
11
5
0
16
93
5
2
0
7
89
9
3
0
12
Numbness
93
5
1
1
7
92
2
5
1
8
88
4
7
0
11
Burning
95
3
2
0
5
98
0
1
1
2
96
1
3
0
4
Paleness
99
0
0
1
1
100
0
0
0
0
99
1
0
0
1
Swelling
98
1
0
1
2
97
1
1
1
3
97
0
3
0
3
Pain
92
2
3
3
8
84
8
6
2
16
84
6
8
2
16
Stiffness
93
4
2
1
7
91
3
4
2
9
89
4
7
0
11
Cramping
98
1
1
0
2
96
1
2
1
4
98
1
1
0
2
Total
30
47
17
6
70
49
27
21
3
51
39
47
10
4
61
*The same subject may have more than one symptom occurring at different frequencies.Table 9
Locations and persistency of the work-related musculoskeletal symptoms among the examined computer users/operators.
Symptoms
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
None
One  hr
One day
One week
One month to 1 year
Total*
None
One  hr
One day
One week
One month to 1 year
Total*
None
One  Hr
One day
One week
One month to 1 year
Total*
Neck
78
6
10
3
3
22
77
7
10
4
2
23
81
10
5
2
2
19
Shoulder
27
7
13
5
0
28
75
10
10
1
4
25
83
8
6
3
0
17
Arm and elbow
89
5
5
0
1
11
92
1
5
0
2
8
97
1
1
1
0
3
Forearm
91
1
6
1
1
9
90
4
3
0
3
10
98
3
1
0
0
2
Fingers
88
4
7
0
1
12
91
2
5
0
2
9
91
3
4
2
0
9
Higher back
75
7
16
1
1
25
82
5
10
2
1
18
84
3
8
5
0
16
Lower back
67
8
19
2
4
33
82
9
6
1
2
18
70
10
14
5
1
30
Buttock
97
0
2
0
1
3
87
5
7
1
0
13
97
2
1
0
0
3
Thigh
96
1
2
1
0
4
87
4
7
0
2
13
93
3
3
0
1
7
Knee
93
3
3
0
1
7
92
4
3
1
0
8
89
4
5
2
0
11
Leg
93
2
3
1
1
7
94
3
1
1
1
6
95
1
2
2
0
5
Foot
94
3
1
1
1
6
91
4
4
0
1
9
94
1
2
2
1
6
All symptoms
30
27
30
9
4
70
49
25
18
4
4
51
39
23
24
10
4
61
*The symptoms may occur in more than one location at the same frequencies.Only 41% and 46% of KAU and STC populations, in comparison to 61% of SAUDIA population, reported eye and vision symptoms. The most predominant eye symptoms were eye redness, tearing, pain, and redness, and the most predominant vision symptoms were blurring, particularly for distance objects, as well as sensitivity to light (Table7).Thirty percent, 49%, and 39% of the KAU, SAUDIA, and STC populations were free from musculoskeletal symptoms. The main occurring symptoms were aching, tingling, numbness, pain, and stiffness, which occurred, mostly sometimes, and, to a less extent, often (Table8). The highest incidences of the symptoms were at the operators’ higher and lower back, neck and shoulder, arm, elbow, forearm, and fingers and then at the lower limbs (buttock to foot) (Table 9).


### 3.4. Factors Affecting Incidence of Complaints

The effects of age and duration of employment (i.e., work) on the incidence of operators’ health complaints are shown in Tables10 and 11. There has been general trend of increasing the different complaints by age, particularly among those exceeding 35 years of age (Table 10). This observation is further confirmed in Table 11, where the operators working for >10 years had, generally, the highest incidences of the general and the eye and vision complaints, as well as the incidences of other complaints, but to a less extent.Table 10
Incidence of complaints as related to age of computer users/operators.
Age (year)
Number ofoperators
Ergonomic scoremean (SD)
Duration of employment  (year)mean (SD)
Computer use (hours/day)mean (SD)
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
20–29
54
37.4
2.6
6.4
7
24
31
26
16
8
25
(5.0)
(1.1)
(1.5)
(13.0)
(44.4)
(57.4)
(48.1)
(29.6)
(14.8)
(46.3)
30–39
29
36.7
8.8
5.8
5
17
15
16
12
4
16
(6.3)
(3.5)
(2.0)
(17.2)
(58.6)
(51.7)
(55.2)
(41.4)
(13.8)
(55.2)
40+
17
34.9
17.6
6.0
3
10
11
9
4
3
7
(6.5)
(7.2)
(2.5)
(17.6)
(58.8)
(64.7)
(52.9)
(23.5)
(17.6)
(41.2)
Saudi Airlines Ticket reservation operators
20–29
17
69.1
2.0
6.0
4
7
8
7
4
3
8
(7.7)
(1.3)
(0.0)
(23.5)
(41.2)
(47.1)
(41.2)
(23.5)
(17.6)
(47.1)
30–39
28
71.6
14.9
6.0
11
13
10
10
7
6
7
(11.0)
(3.1)
(0.0)
(39.3)
(46.4)
(35.7)
(35.7)
(25.0)
(21.4)
(25.0)
40+
55
72.8
26.4
6.0
26
20
21
18
11
14
20
(13.6)
(4.9)
(0.0)
(47.3)
(36.4)
(38.2)
(32.7)
(20.0)
(25.5)
(36.4)
Saudi Telecom Co. computer operators
20–29
66
78.4
3.2
7.2
12
40
38
34
19
32
7
(9.8)
(1.4)
(1.6)
(18.2)
(60.6)
(57.6)
(51.5)
(28.8)
(48.5)
(10.6)
30–39
21
82.2
8.7
7.4
3
14
13
12
5
10
6
(10.9)
(3.1)
(1.5)
(14.3)
(66.7)
(61.9)
(57.1)
(12.4)
(47.6)
(28.6)
40+
13
95.9
21.6
6.6
1
9
8
5
2
8
0
(4.1)
(3.2)
(1.6)
(7.7)
(69.2)
(61.5)
(38.5)
(15.4)
(61.5)
(0.0)Table 11
Incidence of complaints as related to duration of work.
Duration ofemployment(year)
Number ofoperators
Ergonomic scoremean (SD)
Age (year)mean (SD)
Computer use (hours/day)mean (SD)
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
≤2
35
37.6
25.8
6.5
6
14
17
16
7
4
14
(4.4)
(2.7)
(1.7)
(17.1)
(40.0)
(48.6)
(45.7)
(20.0)
(11.4)
(40.0)
3–9
38
36.2
29.3
6.4
5
21
22
22
14
6
22
(6.3)
(3.5)
(1.9)
(13.2)
(55.3)
(57.9)
(57.9)
(36.8)
(15.8)
(57.9)
≤10
27
36.4
42.3
5.8
4
16
18
13
10
5
12
(7.9)
(4.5)
(2.2)
(14.8)
(59.3)
(66.7)
(48.1)
(37.0)
(18.5)
(44.4)
Saudi Airlines Ticket reservation operators
≤2
12
69.7
23.3
6.0
3
5
6
5
2
3
5
(8.2)
(1.6)
(0.0)
(25.0)
(41.7)
(50.0)
(41.7)
(16.7)
(25.0)
(41.7)
3–9
11
68.9
30.6
6.0
4
5
3
4
2
1
4
(7.4)
(2.1)
(0.0)
(36.4)
(45.5)
(27.3)
(36.4)
(18.2)
(9.1)
(36.4)
≤10
77
71.9
43.1
6.0
34
30
30
26
18
19
25
(13.7)
(2.9)
(0.0)
(44.2)
(39.0)
(39.0)
(33.8)
(23.4)
(24.7)
(32.5)
Saudi Telecom Co. computer operators
≤2
31
76.7
25.2
7.2
6
17
18
17
9
14
6
(13.5)
(2.2)
(1.9)
(19.4)
(54.8)
(58.1)
(54.8)
(29.0)
(45.2)
(19.4)
3–9
47
80.3
27.8
7.1
8
28
24
21
13
26
4
(7.7)
(1.9)
(1.5)
(17.0)
(59.6)
(51.1)
(44.7)
(27.7)
(55.3)
(8.5)
≤10
22
90.3
40.8
7.1
2
18
17
13
4
10
3
(13.2)
(5.4)
(1.8)
(9.1)
(81.8)
(77.3)
(59.1)
(18.2)
(45.5)
(13.6)The impact of the ergonomics score of the workstation on the incidence of operators’ complaints is shown in Table12, where there has been a trend of decrease in the incidence of operators’ general complaints, eye and vision complaints, and musculoskeletal complaints, particularly the extremities and the lower trunk complaints, by the increase of the ergonomics score of their workstations.Table 12
Incidence of complaints as related to ergonomic score of workstation.
Ergonomic score
Number ofoperators
Age (year)mean (SD)
Duration of employment  (year)mean (SD)
Computer use (hours/day)mean (SD)
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
<60
18
32.7
7.7
5.5
2
11
12
10
9
5
8
(6.9)
(4.3)
(1.6)
(11.1)
(61.1)
(66.7)
(55.6)
(50.0)
(27.8)
(44.4)
60–79
41
31.7
7.2
6.5
7
20
22
19
11
7
21
(7.6)
(6.1)
(1.5)
(17.1)
(48.8)
(48.8)
(46.3)
(26.8)
(17.1)
(51.2)
80+
27
30.1
6.5
6.1
6
20
26
22
11
4
19
(5.8)
(4.4)
(2.1)
(14.6)
(48.8)
(63.4)
(53.7)
(26.8)
(9.8)
(46.3)
Saudi Airlines Ticket reservation operators
<60
21
40.4
20.3
6.0
8
10
10
6
4
4
8
(10.2)
(11.4)
(0.0)
(38.1)
(47.6)
(47.6)
(28.6)
(19.0)
(19.0)
(38.1)
60–79
57
38.9
18.4
6.0
23
20
20
21
10
14
21
(6.7)
(7.9)
(0.0)
(40.4)
(35.1)
(35.1)
(36.8)
(17.5)
(24.6)
(36.8)
80+
22
40.0
5.5
6.0
10
10
9
8
8
5
5
(4.5)
(5.2)
(0.0)
(45.5)
(45.5)
(40.9)
(36.4)
(36.4)
(22.7)
(22.7)
Saudi Telecom Co. computer operators
<60
6
26.1
3.6
7.8
1
3
3
3
2
4
3
(2.1)
(2.8)
(0.9)
(16.7)
(50.0)
(50.0)
(50.0)
(33.3)
(66.7)
(50.0)
60–79
35
27.0
3.8
6.8
5
24
19
19
10
19
8
(2.6)
(2.0)
(1.3)
(14.3)
(68.6)
(54.3)
(54.3)
(28.6)
(54.3)
(22.9)
80+
59
31.9
8.8
7.2
8
36
37
29
14
27
2
(5.8)
(5.8)
(1.6)
(13.6)
(61.0)
(62.7)
(49.2)
(23.7)
(45.8)
(3.4)Out of the many factors considered for their effects on the incidences of the operators’ complaints and symptoms, the smoking habit, the type of work, workers satisfaction, and the operators’ history of musculoskeletal complaints and of eye and vision before joining present work showed some effects as indicated in Tables13–17. Smoking appears to have some effect on increasing the incidences of the general and eye and vision complaints, particularly among KAU computer users and SAUDIA operators, and on the lower extremities and lower trunk complaints, to some extent (Table 13).Table 13
Incidence of complaints as related to smoking habits.
Smoking habit
Number ofoperators
Ergonomic scoremean (SD)
Age (year)mean (SD)
Duration of employment  (year)mean (SD)
Computer use (hours/day)mean (SD)
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
Nonsmokers
79
37.2
30.7
6.3
6.2
12
37
22
40
24
10
37
(7.6)
(9.1)
(6.6)
(2.2)
(15.2)
(46.8)
(27.8)
(50.6)
(30.4)
(12.7)
(46.8)
Smokers
21
35.3
34.2
9.0
6.2
3
14
17
11
7
5
11
(7.4)
(9.3)
(7.9)
(3.1)
(14.3)
(66.7)
(81.0)
(52.4)
(33.3)
(23.8)
(52.4)
Saudi Airlines Ticket Reservation operators
Nonsmokers
75
72.2
39.5
18.9
6.0
32
27
26
21
15
15
21
(13.8)
(9.1)
(10.7)
(0.0)
(42.7)
(36.0)
(34.7)
(28.0)
(20.0)
(20.0)
(28.0)
Smokers
25
69.0
40.4
20.9
6.0
9
13
13
14
7
8
13
(10.4)
(9.3)
(9.9)
(0.0)
(36.0)
(52.0)
(52.0)
(56.0)
(28.0)
(32.0)
(52.0)
Saudi Telecom Co. computer operators
Nonsmokers
62
81.8
29.0
6.7
7.0
9
38
35
34
16
33
8
(15.5)
(6.5)
(6.6)
(2.1)
(14.5)
(61.3)
(56.5)
(54.8)
(25.8)
(53.2)
(12.9)
Smokers
38
81.0
30.3
7.5
8.7
7
25
24
17
10
17
5
(12.5)
(8.4)
(8.3)
(8.6)
(18.4)
(65.8)
(63.2)
(44.7)
(26.3)
(44.7)
(13.2)Table 14
Incidence of complaints as related to type of work.
Type ofwork
Number ofoperators
Ergonomic scoremean ± SD
Age (year)mean ± SD
Duration of employment  (year)mean ± SD
Computer use (hours/day)mean ± SD
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
Data entry
22
37.5
29.4
5.6
7.0
3
14
10
12
7
1
10
(6.6)
(9.4)
(7.8)
(2.1)
(13.6)
(63.4)
(45.5)
(54.5)
(31.8)
(4.5)
(45.5)
Typist
23
36.9
33.8
9.8
7.1
3
17
14
14
8
3
10
(8.2)
(9.3)
(6.7)
(3.0)
(13.0)
(73.9)
(60.9)
(60.9)
(34.8)
(13.0)
(43.5)
Data acquisition
18
35.4
33.5
8.6
6.0
1
13
12
8
3
4
11
(6.3)
(10.6)
(7.3)
(2.0)
(5.6)
(72.2)
(66.7)
(44.4)
(16.7)
(22.2)
(61.1)
Communication task
8
37.0
28.4
4.1
6.6
3
3
3
3
2
0
3
(5.8)
(5.9)
(5.9)
(5.5)
(37.5)
(37.5)
(37.5)
(37.5)
(25.0)
(0.0)
(37.5)
Comprehensive
29
36.8
30.0
5.4
4.8
4
10
20
13
4
6
14
(9.2)
(7.5)
(6.0)
(1.9)
(13.8)
(34.5)
(69.0)
(44.8)
(13.8)
(20.7)
(48.3)
Saudi Airlines Ticket reservation operators
Data entry
54
69.6
38.3
17.2
6.0
11
28
26
24
14
15
23
(12.0)
(10.4)
(11.1)
(0.0)
(20.4)
(51.8)
(48.1)
(44.4)
(25.9)
(27.8)
(42.6)
Data acquisition
23
77.8
43.3
26.2
6.0
17
3
4
3
2
2
2
(15.8)
(6.1)
(7.1)
(0.0)
(73.9)
(13.0)
(17.4)
(13.0)
(8.7)
(8.7)
(8.7)
Communication task
20
66.6
36.7
16.1
6.0
10
9
9
8
6
6
9
(9.6)
(8.6)
(10.8)
(0.0)
(50.0)
(45.0)
(45.0)
(40.0)
(30.0)
(30.0)
(45.0)
Comprehensive
3
82.0
39.0
19.3
6.0
3
0
0
0
0
0
0
(14.0)
(1.7)
(4.1)
(0.0)
(100)
(0.0)
(0.0)
(0.0)
(0.0)
(0.0)
(0.0)
Saudi Telecom Co. computer operators
Data entry
33
83.4
31.7
8.9
7.2
7
22
22
18
6
16
2
(12.7)
(7.9)
(8.1)
(1.8)
(21.2)
(66.7)
(66.7)
(54.5)
(18.2)
(48.5)
(6.1)
Data acquisition
9
85.1
30.0
5.3
9.3
0
6
7
7
3
3
1
(8.3)
(3.7)
(4.7)
(2.0)
(0.0)
(66.7)
(77.8)
(77.8)
(33.3)
(33.3)
(11.1)
Communication task
53
79.4
28.2
5.4
6.9
8
32
28
26
14
30
9
(15.7)
(7.0)
(6.8)
(2.1)
(15.1)
(60.4)
(52.8)
(49.1)
(26.4)
(56.6)
(17.0)
Comprehensive
5
85.2
34.8
12.8
4.4
1
3
2
0
3
1
1
(17.1)
(7.3)
(9.3)
(2.2)
(20.0)
(60.0)
(40.0)
(0.0)
(60.0)
(20.0)
(20.0)Table 15
Incidence of complaints as related to work satisfaction.
Worksatisfaction
Number ofoperators
Ergonomic scoremean ± SD
Age (year)mean ± SD
Duration of employment  (year)mean ± SD
Computer use (hours/day)mean ± SD
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
Very satisfied
39
38.0
33.7
8.5
6.4
8
18
21
21
7
3
14
(6.5)
(10.2)
(8.2)
(2.7)
(20.5)
(46.2)
(53.8)
(53.8)
(17.9)
(7.7)
(35.9)
Satisfied
43
36.6
30.1
5.3
6.0
6
21
22
18
10
7
24
(8.2)
(9.2)
(5.3)
(2.2)
(14.0)
(48.8)
(51.2)
(41.9)
(23.3)
(16.3)
(55.8)
Satisfaction to some extent
10
33.5
34.4
8.4
6.2
1
7
4
5
5
1
3
(6.9)
(11.2)
(8.1)
(2.4)
(10.0)
(70.0)
(40.0)
(50.0)
(50.0)
(10.0)
(30.0)
Not satisfied
8
33.5
28.5
6.0
6.4
0
5
8
5
5
2
6
(9.7)
(3.9)
(5.0)
(2.2)
(0.0)
(62.5)
(100.0)
(62.5)
(62.5)
(25.0)
(75.0)
Saudi Airlines Ticket reservation operators
Very satisfied
35
76.2
39.6
18.9
6.0
22
7
7
7
7
5
7
(14.4)
(8.4)
(11.5)
(0.0)
(62.9)
(20.0)
(20.0)
(20.0)
(20.0)
(14.3)
(20.0)
Satisfied
37
66.8
38.9
19.4
6.0
11
16
18
14
8
11
17
(11.6)
(10.5)
(11.3)
(0.0)
(29.7)
(43.2)
(48.6)
(37.8)
(21.6)
(29.7)
(45.9)
Satisfaction to some extent
14
74.0
37.8
17.6
6.0
4
7
6
8
2
3
3
(11.0)
(8.0)
(9.1)
(0.0)
(28.6)
(50.0)
(42.9)
(57.1)
(14.3)
(21.4)
(21.4)
Not satisfied
14
68.6
40.8
19.3
6.0
4
10
8
6
5
4
7
(11.6)
(7.6)
(8.6)
(0.0)
(28.6)
(71.4)
(57.1)
(42.9)
(35.7)
(28.6)
(50.0)
Saudi Telecom Co. computer operators
Very satisfied
29
82.1
30.1
7.2
7.5
6
14
11
16
7
11
4
(16.6)
(7.3)
(7.2)
(2.1)
(20.9)
(48.3)
(37.9)
(55.2)
(24.1)
(37.9)
(13.8)
Satisfied
31
84.1
31.0
7.5
6.9
5
22
21
15
8
16
6
(11.0)
(8.7)
(7.4)
(2.0)
(16.1)
(71.0)
(67.7)
(48.4)
(25.8)
(51.6)
(19.4)
Satisfaction to some extent
27
79.3
28.5
5.1
7.0
5
17
18
13
7
14
2
(14.8)
(5.6)
(6.3)
(2.2)
(18.5)
(63.0)
(66.7)
(48.1)
(25.9)
(51.9)
(7.4)
Not satisfied
13
78.4
29.0
7.3
7.0
0
10
9
7
4
9
1
(15.1)
(6.2)
(7.5)
(2.2)
(0.0)
(76.9)
(69.2)
(53.8)
(30.8)
(69.2)
(7.7)Table 16
Incidence of eye and vision complaints as related to previous ailments of computer users/operators.
Complaints
Number ofoperators
Ergonomic scoremean ± SD
Age (year)mean ± SD
Duration of employment  (year)mean ± SD
Computer use (hours/day)mean ± SD
ComplaintsN (%)
None
General
Eye and vision
King Abdulaziz University computer users
None
58
36.6
30.9
5.4
6.0
12
27
25
(7.5)
(9.2)
(5.6)
(2.0)
(20.7)
(46.6)
(43.1)
Short-sighted
30
37.6
31.3
5.4
6.6
1
20
25
(8.3)
(8.8)
(5.6)
(3.2)
(3.3)
(66.7)
(83.3)
Long-sighted
7
37.2
40.4
18.0
5.7
1
3
3
(6.7)
(11.4)
(10.8)
(2.0)
(14.3)
(42.9)
(42.9)
Others
7
36.5
39.8
11.9
5.6
1
2
5
(4.9)
(13.7)
(12.3)
(2.1)
(14.3)
(28.6)
(71.4)
Saudi Airlines Ticket reservation operators
None
70
71.4
38.9
18.5
6.0
41
18
13
(13.0)
(9.1)
(10.9)
(0.0)
(58.6)
(25.7)
(18.6)
Short-sighted
23
72.2
38.7
18.9
6.0
0
17
19
(13.2)
(10.6)
(11.4)
(0.0)
(0.0)
(73.9)
(82.6)
Long-sighted
2
65.0
47.5
26.5
6.0
0
2
2
(12.8)
(0.7)
(0.7)
(0.0)
(0.0)
(100.0)
(100.0)
Others
5
68.8
43.6
22.8
6.0
0
3
5
(19.0)
(4.8)
(6.1)
(0.0)
(0.0)
(60.0)
(100.0)
Saudi Telecom Co. computer operators
None
58
80.4
29.1
5.8
7.2
13
29
24
(14.9)
(6.9)
(6.0)
(2.0)
(22.4)
(50.0)
(41.4)
Short-sighted
24
84.8
30.3
8.1
6.7
3
19
20
(12.9)
(6.2)
(7.6)
(2.1)
(12.5)
(79.2)
(83.3)
Long-sighted
11
80.0
30.5
6.6
7.2
0
8
8
(13.5)
(9.5)
(8.4)
(2.1)
(0.0)
(72.7)
(72.7)
Others
7
86.0
32.7
10.0
7.4
0
7
7
(14.6)
(9.3)
(10.3)
(2.7)
(0.0)
(100.0)
(100.0)Table 17
Incidence of musculoskeletal complaints as related to previous ailments of computer users/operators.
Complaints
Number ofoperators
Ergonomic scoremean ± SD
Age (year)mean ± SD
Duration of employment  (year)mean ± SD
Computer use (hours/day)mean ± SD
ComplaintsN (%)
None
General
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
None
59
37.6
31.6
6.5
6.0
13
24
20
17
6
20
(7.7)
(9.0)
(6.6)
(2.4)
(22.0)
(40.7)
(33.9)
(28.8)
(10.2)
(33.9)
Neck
22
36.0
29.7
6.3
5.9
1
13
21
9
3
15
(7.3)
(8.2)
(6.6)
(1.5)
(4.5)
(59.1)
(95.5)
(40.9)
(13.6)
(68.2)
Shoulder and arms
11
37.2
29.5
7.2
6.4
1
9
9
8
2
7
(8.8)
(8.8)
(7.8)
(1.5)
(9.1)
(81.8)
(81.8)
(72.7)
(18.2)
(63.6)
Lower trunk
13
32.2
31.4
7.8
7.4
0
11
11
3
3
12
(8.7)
(8.5)
(7.3)
(3.6)
(0.0)
(84.6)
(84.6)
(23.1)
(23.1)
(92.3)
Thigh and leg
5
33.4
34.8
9.6
8.2
0
4
2
1
3
3
(7.0)
(15.8)
(9.0)
(5.6)
(0.0)
(80.0)
(40.0)
(20.0)
(60.0)
(60.0)
Others
1
41.0
35.0
2.0
7.0
0
1
0
0
0
1
(0.0)
(0.0)
(0.0)
(0.0)
(0.0)
(100.0)
(0.0)
(0.0)
(0.0)
(100.0)
Saudi Airlines Ticket reservation operators
None
62
71.4
38.4
18.7
6.0
39
11
8
4
4
7
(13.6)
(9.1)
(11.2)
(0.0)
(62.9)
(17.7)
(12.9)
(6.5)
(6.5)
(11.3)
Neck
24
74.4
39.8
19.4
6.0
0
24
21
12
11
16
(13.4)
(8.9)
(9.7)
(0.0)
(0.0)
(100.0)
(87.5)
(50.0)
(45.8)
(66.7)
Shoulder and arms
11
75.4
42.3
21.8
6.0
0
10
11
7
5
7
(10.4)
(8.4)
(10.0)
(0.0)
(0.0)
(90.9)
(100.0)
(63.6)
(45.5)
(63.6)
Lower trunk
23
70.6
41.7
22.4
6.0
1
15
15
12
14
18
(13.6)
(10.1)
(10.4)
(0.0)
(4.3)
(65.2)
(65.2)
(52.2)
(60.9)
(78.3)
Thigh and leg
8
73.4
40.2
19.0
6.0
1
7
5
6
5
6
(15.2)
(7.7)
(8.9)
(0.0)
(12.5)
(87.5)
(62.5)
(75.0)
(62.5)
(75.0)
Others
1
78.0
45.0
20.0
6.0
0
1
1
0
1
1
(0.0)
(0.0)
(0.0)
(0.0)
(0.0)
(100.0)
(100.0)
(0.0)
(100.0)
(100.0)
Saudi Telecom Co. computer operators
None
55
81.1
29.4
6.4
7.3
13
31
24
7
20
7
(14.5)
(7.7)
(6.9)
(2.0)
(23.6)
(56.4)
(43.6)
(12.7)
(36.4)
(12.7)
Neck
17
82.9
30.1
7.9
6.9
0
16
13
8
12
3
(11.8)
(5.8)
(7.9)
(1.5)
(0.0)
(94.1)
(76.5)
(47.1)
(70.6)
(17.6)
Shoulder and arms
4
84.0
30.0
7.5
6.5
0
4
2
0
1
0
(9.3)
(4.6)
(7.3)
(1.0)
(0.0)
(100.0)
(50.0)
(0.0)
(25.0)
(0.0)
Lower trunk
16
82.3
32.3
8.6
6.8
1
10
7
6
12
1
(15.1)
(8.5)
(8.4)
(3.0)
(6.3)
(62.5)
(43.8)
(37.5)
(75.0)
(6.3)
Thigh and leg
4
84.5
27.2
4.6
7.5
0
1
2
3
3
1
(12.0)
(3.9)
(4.2)
(1.9)
(0.0)
(25.0)
(50.0)
(75.0)
(75.0)
(25.0)
Others
4
72.0
27.7
3.0
6.3
2
1
3
2
2
1
(25.9)
(3.5)
(2.1)
(2.8)
(50.0)
(25.0)
(75.0)
(50.0)
(50.0)
(25.0)It is worth noting that the lowest eye and vision complaints occurred among the operators who had the lowest level of education (i.e., middle education), which might be interpreted by their relatively lower involvement in vision tasks than the operators having higher levels of education.As related to the impact of type of work on the incidence of complaints, results in Table14 show that the operators who were involved in communication tasks in KAU, and in data acquisition in SAUDIA, had the lowest general, eye and vision, neck and shoulder, lower extremities, and lower trunk complaints, as well as those involved in comprehensive activities among all the populations, meanwhile showing the highest freedom from all complaints. It may be noted that the numbers of operators involved in these activities (KAU communication tasks and SAUDIA and STC comprehensive tasks = 8, 3, and 5, resp.) were the lowest among all worker involved in other types of activities which might have some effect on the results.Nevertheless, the work satisfaction showed clear impact on the incidence of health complaints among the examined computer users, where the percentages of those who were free from complaints got higher by the improvement of work satisfaction (Table15); meanwhile, the lowest incidences of mostly all the complaints were the lowest among the very satisfied operators, particularly the SAUDIA and STC operators.The history of previous ailments among computer users/operators, also, had some impact on the reported complaints among them, where the percentages of the present complaints among the subjects who had no previous ailments were less than among the other subjects reporting related ailments’ history (Tables16–18).Table 18
Freedom of computer users/operators from complaints as related to workstation score  number (percent).
Score of workstation
KAU computer users
Saudi Airlines Ticket reservation operators
Saudi Telecom Co. computer operators
Operator sample
Nogeneral complaints
Noeye  and  visioncomplaints
Nomusculo-skeletalcomplaints
Operator sample
Nogeneral complaints
Noeye  and  visioncomplaints
Nomusculo-skeletalcomplaints
Operator sample
Nogeneral complaints
Noeye  and  visioncomplaints
Nomusculo-skeletalcomplaints
<50
8
3
3
1
—
—
—
—
3
1
1
0
(37.5)
(37.5)
(12.5)
(33.3)
(33.3)
(0.0)
50–59
10
4
3
6
21
11
11
13
3
2
2
2
(40)
(30)
(60)
(52.4)
(52.4)
(61.9)
(66.7)
(66.7)
(66.7)
60–69
15
8
6
7
22
13
14
14
11
3
3
3
(53.3)
(40)
(46.7)
(59.1)
(63.6)
(63.6)
(27.3)
(27.3)
(27.3)
70–79
26
13
15
13
35
24
23
18
24
8
13
12
(50)
(57.7)
(50)
(68.6)
(65.7)
(51.4)
(33.3)
(54.2)
(50)
80–89
25
12
10
10
8
4
3
4
23
11
11
12
(48)
(40)
(40)
(50)
(37.5)
(50)
(47.8)
(47.8)
(52.2)
90–100
16
9
5
9
14
8
10
9
36
12
11
15
(56.3)
(31.3)
(56.3)
(57.1)
(71.4)
(64.3)
(33.3)
(30.6)
(41.7)
Total
100
100
100


## 3.1. Ergonomics of the Workstations

The ergonomics scores of the studied workstations in the three institutions are illustrated in Table3 and Figures 1 and 2. The average workstations score in STC has been rated very good (81.5±14.34) which is considerably higher than the scores of both KAU and SAUDIA (73.3+15.13 and 70.3±13.54, resp.) (Figure 2). This might be attributed to the relatively recent establishment of the workstations in STC in comparison to the other two study locations (KAU and SAUDIA). However, the score of the different components varies considerably in the three locations. For example, task and posture has been rated 95% and 90% at STC and SAUDIA, respectively, while it has been the lowest scored component at KAU (54%). Also, work organization has been rated the second highest (98.3%) at SAUDIA while it has been rated the second lowest at KAU (57.7%) and in the middle of the scores at SAUDIA (73.2%). These variations might be attributed to the differences of the type of work and pattern of computer use at the different study locations. The distribution of the ergonomics scores of the examined workstations might be considered to follow normal model but truncated (Figure 2).Table 3
Positive ergonomics components of the examined workstations.
Number
Ergonomics components
KAU* (N = 100)
SAUDIA** (N = 100)
STC*** (N = 100)
Number of positives
Average
Number of positives
Average
Number of positives
Average
I
Noise and thermal environment
1
Quietness
75
84.0
78
81.5
83
86.5
2
Air-conditioning
93
85
90
II
Display screen
3
Monitor location
71
80.4
70
75.4
97
87.4
4
Monitor top
80
100
99
5
Monitor distance from eye
71
100
98
6
Monitor tilting
75
72
97
7
Glare and reflection
68
60
70
8
Image stability
91
67
80
9
Ease of reading
95
68
74
10
Brightness and contrast
92
66
84
III
Desk
11
Space
81
78.4
100
81.4
100
99.4
12
Layout
85
85
99
13
Distance from eye
74
86
100
14
Room for leg
93
65
100
15
Hand/wrist
59
71
98
IV
Mouse
16
Distance from hand
83
77.7
75
71.3
72
71.3
17
Run
76
78
76
18
Operator’s familiarity
74
61
66
V
Seat
19
Height
89
75.3
100
74.7
99
77.7
20
Dimensions
78
72
95
21
Armrest
76
75
77
22
Backrest
64
79
59
23
Pad (foam)
71
60
63
24
Comfort and stability
73
62
73
VI
Space and room layout
25
Adequate access
90
73.7
65
68.9
24
78.7
26
Space around seat
86
100
100
27
Layout
80
61
93
28
Location of equipment
62
61
88
29
Monitors’ positions
51
66
100
30
Obstructions and hazards
75
60
100
31
Housekeeping
72
69
46
VII
Illumination
32
Lighting level
91
72.3
55
48.8
60
86.8
33
Luminaries
66
46
99
34
Effectiveness
61
43
97
35
Background behind screens
71
51
91
VIII
Training and provision of information
36
Use of software
75
71.5
46
47.3
76
60.3
37
Habit keying
73
59
66
38
Adjustment
74
43
65
39
Good posture and visual fatigue
64
41
34
IX
Keyboard
40
Distance
69
69.7
66
66.0
98
95.0
41
Width
73
69
75
42
Height and key angle
67
63
92
X
Footrest
43
Compression of thigh
68
68.0
65
65.0
54
54.0
XI
Document holder
44
Need
64
63.0
90
90.0
39
38.0
45
Balance of head posture
62
90
37
XII
Work organization rating
46
Breaks
79
59.7
100
73.3
88
89.3
47
Urgent peaks  and  interruptions
40
55
83
48
Over time
60
65
97
XIII
Task and posture
49
Phoning while typing
33
54.0
90
95.0
99
90.0
50
Typing posture
75
100
81
Total average score
72.3
71.1
81.0
*KAU = King Abdulaziz University.
**SAUDIA = Saudi Airlines.
***STC = Saudi Telecom Company.Figure 1
Average ergonomics scores of the examined workstation components.Figure 2
Distribution of the ergonomics scores of the examined workstation component.


## 3.2. Characteristics of the Work Population

The demographic and occupational characteristics of the studied populations of the computer users/operators in the three institutions are presented in Tables4 and 5. The populations at the different study locations were mostly young, since 98% of the subjects in both KAU and STC, and 89% at SAUDIA, were younger than 50 years. However, the subjects of the study population at SAUDIA were relatively older since 27% of them were younger than 35 years in comparison to 80% at STC and 68% at KAU (Table 4). The average ages at the KAU, SAUDIA, and STC were 31.5, 39.7, and 30.3 years, respectively. Yet 78% and 73% of the populations at STC and KAU have been employed for less than 10 years, in comparison to 23% at SAUDIA that began using VDT earlier than the other two institutions (Table 5). The average durations of employment at KAU, SAUDIA, and STC were 7.1, 19,7, and 7.4 years, respectively. Meanwhile, the levels of education among KAU and STC populations were higher than the SAUDIA population. For example, 65% and 41% of KAU and STC populations received higher education in comparison to only 23% at SAUDIA population. Also, 16% of the KAU and 5% of the STC populations, respectively, received graduate education (Doctor and/or Master), while none of the subject at SAUDIA population had such education level.Table 4
Demographic characteristics of the study population.
Demographic characteristics
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
Age (years)
20–24
24
9
19
25–29
30
8
47
30–34
14
10
14
35–39
15
18
7
40–44
10
20
8
45–49
5
24
3
50–54
2
9
2
>55
0
2
0
Education
Middle
6
2
2
Secondary (general)
21
71
55
Secondary (technical)
8
4
2
High (technical)
19
2
13
High (administrative)
30
21
23
Graduate (master + doctor)
16
0
5
Smoking index
Nonsmokers
79
76
62
<100
6
5
17
100–199
3
2
9
200–399
2
4
5
400–500
5
3
3
>600
5
10
4
Vision symptoms prior to present work*
None
58
70
58
Short-sighted
30
23
25
Long-sighted
7
2
10
Others
7
5
7
Musculoskeletal symptoms prior to present Work*
None
59
62
55
Neck pain
22
24
17
Shoulder and/or arms pain
11
11
4
Lower trunk pain
13
23
16
Thigh and leg pain
5
8
4
Others
1
1
4
*The same subject might have more than one symptom occurring at different frequencies.Table 5
Occupational characteristics of the study population.
Occupational characteristics
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
Duration of employment (years)
<1
12
7
7
1-2
23
5
24
3-4
20
4
17
5–9
18
7
30
10–14
11
7
5
15–19
7
14
9
20–24
5
20
5
25–29
3
16
3
30–34
1
16
0
≥35
0
4
0
Type of work
Data entry
22
54
33
Data acquisition
18
23
9
Typist
23
0
0
Communication task
8
20
53
Comprehensive office tasks
29
3
5
Duration of formal training (days)On-the-job training only
58
61
28
<50
12
19
24
50–99
5
8
14
100–199
11
2
20
200–299
4
2
4
300–399
4
4
1
400–499
3
0
1
≥500
3
4
8
Work speed
Fast
39
30
45
Average
56
70
49
Slow
5
0
6
Computer use (hrs/day)
3
15
0
2
4
12
0
3
5
9
0
3
6
20
100
53
7
14
0
1
8
22
0
17
9
8
0
21
Nature of daily work on computer
Continuous
61
53
85
Intermittent
39
47
15
Rest pauses of work shift (%)
5–9
10
0
12
10–14
22
0
19
15–19
18
0
16
20–24
19
0
21
25–29
9
100
10
30–34
9
0
11
35–39
7
0
6
≥40
6
0
5
Elements of work satisfaction
Satisfaction by foreman and colleagues  interrelations
100
99
99
Satisfaction by absence work stress
68
60
61
Satisfaction of work control
96
94
96
Satisfaction of job attitude
92
81
82
Satisfaction by vigilance requirement
94
100
94
Satisfaction by nature of work
73
85
55
Satisfaction by absence of repetitive work and monotony
59
34
35
Evaluation of work satisfaction*
Very satisfied
39
35
29
Satisfied
43
37
31
Satisfied to some extent
10
14
27
Not satisfied
8
14
13
*Percent of duration(s) of rest pauses to duration of work shift.Most of the study populations were nonsmokers (79%, 76%, and 62% of subjects at KAU, SAUDIA, and STC, resp.) and 26% of them at STC were light smoker (smoking index less than 200) that might be added to the proportion of the nonsmoker there to be 88%. This distribution might, however, be biased by the relatively young age of the examined subjects.Considerable proportion of the populations either had no vision problems before employment (58%, 70%, and 58% at KAU, SAUDIA, and STC, resp.), or were short-sighted (30%, 23%, and 25%, resp.), while the rest were long-sighted or had other vision problems (14%, 7%, and 17%, resp.). Similarly, more than one half of the populations at the three study locations had no musculoskeletal symptoms before employment (59% at KAU, 62% at SAUDIA, and 55% at STC), while considerable proportions of the populations had neck pain (22% at KAU, 24% at SAUDIA, and 17% at STC). The rest of the populations had such symptom at one or more body locations.More than one half of the population of KAU (52%) was either typist (23%) or involved in comprehensive office tasks (29%), while 40% of them were involved in data entry (22%) and data acquisition (22%). However, at SAUDIA, 77% of the populations were involved in data entry (54%) or data acquisition (23%) while 20% of them were involved in communication tasks and none of them was typist. Similarly, at STC, 86% of the populations were involved in communication tasks (53%) or data entry (33%), and none of them was typist. While 58% and 61% of the populations at KAU and SAUDIA, respectively, received on-the-job training only, and the rest received formal training for different periods, the opposite existed at STC, where 72% of the population received formal training for different periods, and only 28% of the population received on-the-job training only. Consequently, 61% of the populations at KAU and 70% at SAUDIA considered their work speed as average (56% and 70%, resp.) or slow (5% and 0%, resp.), while 45% of the population at STC considered their work speed as fast and 55% of them considered their work speed as either average (49%) or slow (6%).Considerable proportions of the populations at KAU and STC used computer for 7, 8, or 9 hours per day (44% and 39%), while the whole population at SAUDIA (100%), and 53% of them at STC, used computer for 6 hours. On the other hand, 36% of the operators at KAU used computer for 3, 4, or 5 hrs. per day, while none of them at SAUDIA, and 9% of them at STC, operated computers for these shorter periods. However, only 53% of the SAUDIA population operated computer continuously in comparison to 85% of the STC and 61% of KAU populations. Meanwhile, mostly 70% of KAU (69%) and STC (68%) populations had rest pauses <25% of the work shift, and 22% of the two populations got rest pauses 30%–40% of the shift, while the whole SAUDIA population had 25%–29% of their shift as rest pauses, in comparison to 9% and 10% of the other two populations.Eighty-two percent of the computer users in KAU, 72% of the operators at SAUDIA, and 60% of operators at STC were satisfied (and many were even very satisfied) at their work, particularly as related to their excellent satisfaction by their colleagues, work control, job attitude, and vigilance requirement, while the boredom from repetitive work and monotony and the work stress were the main causes of dissatisfaction among them, particularly the SAUDIA and STC populations (41%, 66%, and 65% at KAU, SAUDIA, and STC, resp.).


## 3.3. Operators’ Health Complaints

The operators’ health complaints are presented in Tables6–9. Mostly one third of the operators (35%, 33%, and 27% of KAU, SAUDIA, and STC populations, resp.) was suffering from body fatigue, while 23%, 21%, and 37% of them were suffering from headache, such complaints occurred mostly sometimes among all the populations, however occurred to less extent, particularly among SAUDIA and STC operators. The lack of concentration occurred to less extent (for example, 8%, 6%, and 20% among KAU, SAUDIA, and STC populations, resp.), particularly and daily among SAUDIA and STC populations (Table 6).Table 6
Incidence of work-related general symptoms among the examined computer users/operators.
Symptoms
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
Headache
77
17
6
0
23
79
11
6
4
21
63
25
11
1
37
General body fatigue
65
31
4
0
35
67
17
12
4
33
73
17
9
1
27
Lack of concentration
92
7
1
0
8
94
1
3
2
6
80
10
8
2
20
Total
46
45
9
0
54
60
22
12
6
40
97
1
1
1
3
*The same subject may have more than one symptom occurring at different frequencies.Table 7
Incidence of work-related eye and vision symptoms among the examined computer users/operators.
Symptoms
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
Eye
Eye discomfort
85
12
3
0
15
88
8
4
0
12
91
7
1
1
9
Aches
91
6
3
0
9
96
3
1
0
4
97
1
2
0
3
Pain
95
4
1
0
5
95
2
3
0
5
92
5
3
0
8
Redness
91
6
2
1
9
90
8
1
1
10
93
5
2
0
7
Irritation and itching
93
4
3
0
7
94
3
3
0
6
96
2
2
0
4
Burning
88
9
3
0
12
93
5
2
0
7
95
3
2
0
5
Tearing
82
14
4
0
18
92
3
4
1
8
91
7
1
1
9
Dryness
96
3
1
0
4
92
5
2
1
8
96
3
1
0
4
Vision
Blurred: close objects
92
6
2
0
8
93
3
3
1
7
95
3
2
0
5
Blurred: distant objects
88
9
3
0
12
86
8
5
1
14
91
6
3
0
9
Sensitivity to light
86
10
3
1
14
92
3
4
1
8
84
14
2
0
16
Double flickering
96
4
0
0
4
93
2
4
1
7
97
2
1
0
3
Double vision
99
1
0
0
1
94
3
2
1
6
93
4
3
0
7
Change in color perception
98
2
0
0
2
99
1
0
0
1
97
2
1
0
3
Others
98
1
1
0
2
99
0
1
0
1
0
0
0
0
0
All eye and vision symptoms
41
48
9
2
59
61
22
12
5
39
46
14
15
25
54
*The same subject may have more than one symptom occurring at different frequencies.Table 8
Incidence of work-related musculoskeletal symptoms among the examined computer users/operators.
Symptoms
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
None
Some-times
Often
Daily
Total affected*
Aching
73
18
8
1
27
84
9
6
1
16
69
20
10
1
31
Tingling
84
11
5
0
16
93
5
2
0
7
89
9
3
0
12
Numbness
93
5
1
1
7
92
2
5
1
8
88
4
7
0
11
Burning
95
3
2
0
5
98
0
1
1
2
96
1
3
0
4
Paleness
99
0
0
1
1
100
0
0
0
0
99
1
0
0
1
Swelling
98
1
0
1
2
97
1
1
1
3
97
0
3
0
3
Pain
92
2
3
3
8
84
8
6
2
16
84
6
8
2
16
Stiffness
93
4
2
1
7
91
3
4
2
9
89
4
7
0
11
Cramping
98
1
1
0
2
96
1
2
1
4
98
1
1
0
2
Total
30
47
17
6
70
49
27
21
3
51
39
47
10
4
61
*The same subject may have more than one symptom occurring at different frequencies.Table 9
Locations and persistency of the work-related musculoskeletal symptoms among the examined computer users/operators.
Symptoms
Frequency
KAU (N = 100)
SAUDIA (N = 100)
STC (N = 100)
None
One  hr
One day
One week
One month to 1 year
Total*
None
One  hr
One day
One week
One month to 1 year
Total*
None
One  Hr
One day
One week
One month to 1 year
Total*
Neck
78
6
10
3
3
22
77
7
10
4
2
23
81
10
5
2
2
19
Shoulder
27
7
13
5
0
28
75
10
10
1
4
25
83
8
6
3
0
17
Arm and elbow
89
5
5
0
1
11
92
1
5
0
2
8
97
1
1
1
0
3
Forearm
91
1
6
1
1
9
90
4
3
0
3
10
98
3
1
0
0
2
Fingers
88
4
7
0
1
12
91
2
5
0
2
9
91
3
4
2
0
9
Higher back
75
7
16
1
1
25
82
5
10
2
1
18
84
3
8
5
0
16
Lower back
67
8
19
2
4
33
82
9
6
1
2
18
70
10
14
5
1
30
Buttock
97
0
2
0
1
3
87
5
7
1
0
13
97
2
1
0
0
3
Thigh
96
1
2
1
0
4
87
4
7
0
2
13
93
3
3
0
1
7
Knee
93
3
3
0
1
7
92
4
3
1
0
8
89
4
5
2
0
11
Leg
93
2
3
1
1
7
94
3
1
1
1
6
95
1
2
2
0
5
Foot
94
3
1
1
1
6
91
4
4
0
1
9
94
1
2
2
1
6
All symptoms
30
27
30
9
4
70
49
25
18
4
4
51
39
23
24
10
4
61
*The symptoms may occur in more than one location at the same frequencies.Only 41% and 46% of KAU and STC populations, in comparison to 61% of SAUDIA population, reported eye and vision symptoms. The most predominant eye symptoms were eye redness, tearing, pain, and redness, and the most predominant vision symptoms were blurring, particularly for distance objects, as well as sensitivity to light (Table7).Thirty percent, 49%, and 39% of the KAU, SAUDIA, and STC populations were free from musculoskeletal symptoms. The main occurring symptoms were aching, tingling, numbness, pain, and stiffness, which occurred, mostly sometimes, and, to a less extent, often (Table8). The highest incidences of the symptoms were at the operators’ higher and lower back, neck and shoulder, arm, elbow, forearm, and fingers and then at the lower limbs (buttock to foot) (Table 9).


## 3.4. Factors Affecting Incidence of Complaints

The effects of age and duration of employment (i.e., work) on the incidence of operators’ health complaints are shown in Tables10 and 11. There has been general trend of increasing the different complaints by age, particularly among those exceeding 35 years of age (Table 10). This observation is further confirmed in Table 11, where the operators working for >10 years had, generally, the highest incidences of the general and the eye and vision complaints, as well as the incidences of other complaints, but to a less extent.Table 10
Incidence of complaints as related to age of computer users/operators.
Age (year)
Number ofoperators
Ergonomic scoremean (SD)
Duration of employment  (year)mean (SD)
Computer use (hours/day)mean (SD)
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
20–29
54
37.4
2.6
6.4
7
24
31
26
16
8
25
(5.0)
(1.1)
(1.5)
(13.0)
(44.4)
(57.4)
(48.1)
(29.6)
(14.8)
(46.3)
30–39
29
36.7
8.8
5.8
5
17
15
16
12
4
16
(6.3)
(3.5)
(2.0)
(17.2)
(58.6)
(51.7)
(55.2)
(41.4)
(13.8)
(55.2)
40+
17
34.9
17.6
6.0
3
10
11
9
4
3
7
(6.5)
(7.2)
(2.5)
(17.6)
(58.8)
(64.7)
(52.9)
(23.5)
(17.6)
(41.2)
Saudi Airlines Ticket reservation operators
20–29
17
69.1
2.0
6.0
4
7
8
7
4
3
8
(7.7)
(1.3)
(0.0)
(23.5)
(41.2)
(47.1)
(41.2)
(23.5)
(17.6)
(47.1)
30–39
28
71.6
14.9
6.0
11
13
10
10
7
6
7
(11.0)
(3.1)
(0.0)
(39.3)
(46.4)
(35.7)
(35.7)
(25.0)
(21.4)
(25.0)
40+
55
72.8
26.4
6.0
26
20
21
18
11
14
20
(13.6)
(4.9)
(0.0)
(47.3)
(36.4)
(38.2)
(32.7)
(20.0)
(25.5)
(36.4)
Saudi Telecom Co. computer operators
20–29
66
78.4
3.2
7.2
12
40
38
34
19
32
7
(9.8)
(1.4)
(1.6)
(18.2)
(60.6)
(57.6)
(51.5)
(28.8)
(48.5)
(10.6)
30–39
21
82.2
8.7
7.4
3
14
13
12
5
10
6
(10.9)
(3.1)
(1.5)
(14.3)
(66.7)
(61.9)
(57.1)
(12.4)
(47.6)
(28.6)
40+
13
95.9
21.6
6.6
1
9
8
5
2
8
0
(4.1)
(3.2)
(1.6)
(7.7)
(69.2)
(61.5)
(38.5)
(15.4)
(61.5)
(0.0)Table 11
Incidence of complaints as related to duration of work.
Duration ofemployment(year)
Number ofoperators
Ergonomic scoremean (SD)
Age (year)mean (SD)
Computer use (hours/day)mean (SD)
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
≤2
35
37.6
25.8
6.5
6
14
17
16
7
4
14
(4.4)
(2.7)
(1.7)
(17.1)
(40.0)
(48.6)
(45.7)
(20.0)
(11.4)
(40.0)
3–9
38
36.2
29.3
6.4
5
21
22
22
14
6
22
(6.3)
(3.5)
(1.9)
(13.2)
(55.3)
(57.9)
(57.9)
(36.8)
(15.8)
(57.9)
≤10
27
36.4
42.3
5.8
4
16
18
13
10
5
12
(7.9)
(4.5)
(2.2)
(14.8)
(59.3)
(66.7)
(48.1)
(37.0)
(18.5)
(44.4)
Saudi Airlines Ticket reservation operators
≤2
12
69.7
23.3
6.0
3
5
6
5
2
3
5
(8.2)
(1.6)
(0.0)
(25.0)
(41.7)
(50.0)
(41.7)
(16.7)
(25.0)
(41.7)
3–9
11
68.9
30.6
6.0
4
5
3
4
2
1
4
(7.4)
(2.1)
(0.0)
(36.4)
(45.5)
(27.3)
(36.4)
(18.2)
(9.1)
(36.4)
≤10
77
71.9
43.1
6.0
34
30
30
26
18
19
25
(13.7)
(2.9)
(0.0)
(44.2)
(39.0)
(39.0)
(33.8)
(23.4)
(24.7)
(32.5)
Saudi Telecom Co. computer operators
≤2
31
76.7
25.2
7.2
6
17
18
17
9
14
6
(13.5)
(2.2)
(1.9)
(19.4)
(54.8)
(58.1)
(54.8)
(29.0)
(45.2)
(19.4)
3–9
47
80.3
27.8
7.1
8
28
24
21
13
26
4
(7.7)
(1.9)
(1.5)
(17.0)
(59.6)
(51.1)
(44.7)
(27.7)
(55.3)
(8.5)
≤10
22
90.3
40.8
7.1
2
18
17
13
4
10
3
(13.2)
(5.4)
(1.8)
(9.1)
(81.8)
(77.3)
(59.1)
(18.2)
(45.5)
(13.6)The impact of the ergonomics score of the workstation on the incidence of operators’ complaints is shown in Table12, where there has been a trend of decrease in the incidence of operators’ general complaints, eye and vision complaints, and musculoskeletal complaints, particularly the extremities and the lower trunk complaints, by the increase of the ergonomics score of their workstations.Table 12
Incidence of complaints as related to ergonomic score of workstation.
Ergonomic score
Number ofoperators
Age (year)mean (SD)
Duration of employment  (year)mean (SD)
Computer use (hours/day)mean (SD)
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
<60
18
32.7
7.7
5.5
2
11
12
10
9
5
8
(6.9)
(4.3)
(1.6)
(11.1)
(61.1)
(66.7)
(55.6)
(50.0)
(27.8)
(44.4)
60–79
41
31.7
7.2
6.5
7
20
22
19
11
7
21
(7.6)
(6.1)
(1.5)
(17.1)
(48.8)
(48.8)
(46.3)
(26.8)
(17.1)
(51.2)
80+
27
30.1
6.5
6.1
6
20
26
22
11
4
19
(5.8)
(4.4)
(2.1)
(14.6)
(48.8)
(63.4)
(53.7)
(26.8)
(9.8)
(46.3)
Saudi Airlines Ticket reservation operators
<60
21
40.4
20.3
6.0
8
10
10
6
4
4
8
(10.2)
(11.4)
(0.0)
(38.1)
(47.6)
(47.6)
(28.6)
(19.0)
(19.0)
(38.1)
60–79
57
38.9
18.4
6.0
23
20
20
21
10
14
21
(6.7)
(7.9)
(0.0)
(40.4)
(35.1)
(35.1)
(36.8)
(17.5)
(24.6)
(36.8)
80+
22
40.0
5.5
6.0
10
10
9
8
8
5
5
(4.5)
(5.2)
(0.0)
(45.5)
(45.5)
(40.9)
(36.4)
(36.4)
(22.7)
(22.7)
Saudi Telecom Co. computer operators
<60
6
26.1
3.6
7.8
1
3
3
3
2
4
3
(2.1)
(2.8)
(0.9)
(16.7)
(50.0)
(50.0)
(50.0)
(33.3)
(66.7)
(50.0)
60–79
35
27.0
3.8
6.8
5
24
19
19
10
19
8
(2.6)
(2.0)
(1.3)
(14.3)
(68.6)
(54.3)
(54.3)
(28.6)
(54.3)
(22.9)
80+
59
31.9
8.8
7.2
8
36
37
29
14
27
2
(5.8)
(5.8)
(1.6)
(13.6)
(61.0)
(62.7)
(49.2)
(23.7)
(45.8)
(3.4)Out of the many factors considered for their effects on the incidences of the operators’ complaints and symptoms, the smoking habit, the type of work, workers satisfaction, and the operators’ history of musculoskeletal complaints and of eye and vision before joining present work showed some effects as indicated in Tables13–17. Smoking appears to have some effect on increasing the incidences of the general and eye and vision complaints, particularly among KAU computer users and SAUDIA operators, and on the lower extremities and lower trunk complaints, to some extent (Table 13).Table 13
Incidence of complaints as related to smoking habits.
Smoking habit
Number ofoperators
Ergonomic scoremean (SD)
Age (year)mean (SD)
Duration of employment  (year)mean (SD)
Computer use (hours/day)mean (SD)
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
Nonsmokers
79
37.2
30.7
6.3
6.2
12
37
22
40
24
10
37
(7.6)
(9.1)
(6.6)
(2.2)
(15.2)
(46.8)
(27.8)
(50.6)
(30.4)
(12.7)
(46.8)
Smokers
21
35.3
34.2
9.0
6.2
3
14
17
11
7
5
11
(7.4)
(9.3)
(7.9)
(3.1)
(14.3)
(66.7)
(81.0)
(52.4)
(33.3)
(23.8)
(52.4)
Saudi Airlines Ticket Reservation operators
Nonsmokers
75
72.2
39.5
18.9
6.0
32
27
26
21
15
15
21
(13.8)
(9.1)
(10.7)
(0.0)
(42.7)
(36.0)
(34.7)
(28.0)
(20.0)
(20.0)
(28.0)
Smokers
25
69.0
40.4
20.9
6.0
9
13
13
14
7
8
13
(10.4)
(9.3)
(9.9)
(0.0)
(36.0)
(52.0)
(52.0)
(56.0)
(28.0)
(32.0)
(52.0)
Saudi Telecom Co. computer operators
Nonsmokers
62
81.8
29.0
6.7
7.0
9
38
35
34
16
33
8
(15.5)
(6.5)
(6.6)
(2.1)
(14.5)
(61.3)
(56.5)
(54.8)
(25.8)
(53.2)
(12.9)
Smokers
38
81.0
30.3
7.5
8.7
7
25
24
17
10
17
5
(12.5)
(8.4)
(8.3)
(8.6)
(18.4)
(65.8)
(63.2)
(44.7)
(26.3)
(44.7)
(13.2)Table 14
Incidence of complaints as related to type of work.
Type ofwork
Number ofoperators
Ergonomic scoremean ± SD
Age (year)mean ± SD
Duration of employment  (year)mean ± SD
Computer use (hours/day)mean ± SD
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
Data entry
22
37.5
29.4
5.6
7.0
3
14
10
12
7
1
10
(6.6)
(9.4)
(7.8)
(2.1)
(13.6)
(63.4)
(45.5)
(54.5)
(31.8)
(4.5)
(45.5)
Typist
23
36.9
33.8
9.8
7.1
3
17
14
14
8
3
10
(8.2)
(9.3)
(6.7)
(3.0)
(13.0)
(73.9)
(60.9)
(60.9)
(34.8)
(13.0)
(43.5)
Data acquisition
18
35.4
33.5
8.6
6.0
1
13
12
8
3
4
11
(6.3)
(10.6)
(7.3)
(2.0)
(5.6)
(72.2)
(66.7)
(44.4)
(16.7)
(22.2)
(61.1)
Communication task
8
37.0
28.4
4.1
6.6
3
3
3
3
2
0
3
(5.8)
(5.9)
(5.9)
(5.5)
(37.5)
(37.5)
(37.5)
(37.5)
(25.0)
(0.0)
(37.5)
Comprehensive
29
36.8
30.0
5.4
4.8
4
10
20
13
4
6
14
(9.2)
(7.5)
(6.0)
(1.9)
(13.8)
(34.5)
(69.0)
(44.8)
(13.8)
(20.7)
(48.3)
Saudi Airlines Ticket reservation operators
Data entry
54
69.6
38.3
17.2
6.0
11
28
26
24
14
15
23
(12.0)
(10.4)
(11.1)
(0.0)
(20.4)
(51.8)
(48.1)
(44.4)
(25.9)
(27.8)
(42.6)
Data acquisition
23
77.8
43.3
26.2
6.0
17
3
4
3
2
2
2
(15.8)
(6.1)
(7.1)
(0.0)
(73.9)
(13.0)
(17.4)
(13.0)
(8.7)
(8.7)
(8.7)
Communication task
20
66.6
36.7
16.1
6.0
10
9
9
8
6
6
9
(9.6)
(8.6)
(10.8)
(0.0)
(50.0)
(45.0)
(45.0)
(40.0)
(30.0)
(30.0)
(45.0)
Comprehensive
3
82.0
39.0
19.3
6.0
3
0
0
0
0
0
0
(14.0)
(1.7)
(4.1)
(0.0)
(100)
(0.0)
(0.0)
(0.0)
(0.0)
(0.0)
(0.0)
Saudi Telecom Co. computer operators
Data entry
33
83.4
31.7
8.9
7.2
7
22
22
18
6
16
2
(12.7)
(7.9)
(8.1)
(1.8)
(21.2)
(66.7)
(66.7)
(54.5)
(18.2)
(48.5)
(6.1)
Data acquisition
9
85.1
30.0
5.3
9.3
0
6
7
7
3
3
1
(8.3)
(3.7)
(4.7)
(2.0)
(0.0)
(66.7)
(77.8)
(77.8)
(33.3)
(33.3)
(11.1)
Communication task
53
79.4
28.2
5.4
6.9
8
32
28
26
14
30
9
(15.7)
(7.0)
(6.8)
(2.1)
(15.1)
(60.4)
(52.8)
(49.1)
(26.4)
(56.6)
(17.0)
Comprehensive
5
85.2
34.8
12.8
4.4
1
3
2
0
3
1
1
(17.1)
(7.3)
(9.3)
(2.2)
(20.0)
(60.0)
(40.0)
(0.0)
(60.0)
(20.0)
(20.0)Table 15
Incidence of complaints as related to work satisfaction.
Worksatisfaction
Number ofoperators
Ergonomic scoremean ± SD
Age (year)mean ± SD
Duration of employment  (year)mean ± SD
Computer use (hours/day)mean ± SD
ComplaintsN (%)
None
General
Eye and vision
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
Very satisfied
39
38.0
33.7
8.5
6.4
8
18
21
21
7
3
14
(6.5)
(10.2)
(8.2)
(2.7)
(20.5)
(46.2)
(53.8)
(53.8)
(17.9)
(7.7)
(35.9)
Satisfied
43
36.6
30.1
5.3
6.0
6
21
22
18
10
7
24
(8.2)
(9.2)
(5.3)
(2.2)
(14.0)
(48.8)
(51.2)
(41.9)
(23.3)
(16.3)
(55.8)
Satisfaction to some extent
10
33.5
34.4
8.4
6.2
1
7
4
5
5
1
3
(6.9)
(11.2)
(8.1)
(2.4)
(10.0)
(70.0)
(40.0)
(50.0)
(50.0)
(10.0)
(30.0)
Not satisfied
8
33.5
28.5
6.0
6.4
0
5
8
5
5
2
6
(9.7)
(3.9)
(5.0)
(2.2)
(0.0)
(62.5)
(100.0)
(62.5)
(62.5)
(25.0)
(75.0)
Saudi Airlines Ticket reservation operators
Very satisfied
35
76.2
39.6
18.9
6.0
22
7
7
7
7
5
7
(14.4)
(8.4)
(11.5)
(0.0)
(62.9)
(20.0)
(20.0)
(20.0)
(20.0)
(14.3)
(20.0)
Satisfied
37
66.8
38.9
19.4
6.0
11
16
18
14
8
11
17
(11.6)
(10.5)
(11.3)
(0.0)
(29.7)
(43.2)
(48.6)
(37.8)
(21.6)
(29.7)
(45.9)
Satisfaction to some extent
14
74.0
37.8
17.6
6.0
4
7
6
8
2
3
3
(11.0)
(8.0)
(9.1)
(0.0)
(28.6)
(50.0)
(42.9)
(57.1)
(14.3)
(21.4)
(21.4)
Not satisfied
14
68.6
40.8
19.3
6.0
4
10
8
6
5
4
7
(11.6)
(7.6)
(8.6)
(0.0)
(28.6)
(71.4)
(57.1)
(42.9)
(35.7)
(28.6)
(50.0)
Saudi Telecom Co. computer operators
Very satisfied
29
82.1
30.1
7.2
7.5
6
14
11
16
7
11
4
(16.6)
(7.3)
(7.2)
(2.1)
(20.9)
(48.3)
(37.9)
(55.2)
(24.1)
(37.9)
(13.8)
Satisfied
31
84.1
31.0
7.5
6.9
5
22
21
15
8
16
6
(11.0)
(8.7)
(7.4)
(2.0)
(16.1)
(71.0)
(67.7)
(48.4)
(25.8)
(51.6)
(19.4)
Satisfaction to some extent
27
79.3
28.5
5.1
7.0
5
17
18
13
7
14
2
(14.8)
(5.6)
(6.3)
(2.2)
(18.5)
(63.0)
(66.7)
(48.1)
(25.9)
(51.9)
(7.4)
Not satisfied
13
78.4
29.0
7.3
7.0
0
10
9
7
4
9
1
(15.1)
(6.2)
(7.5)
(2.2)
(0.0)
(76.9)
(69.2)
(53.8)
(30.8)
(69.2)
(7.7)Table 16
Incidence of eye and vision complaints as related to previous ailments of computer users/operators.
Complaints
Number ofoperators
Ergonomic scoremean ± SD
Age (year)mean ± SD
Duration of employment  (year)mean ± SD
Computer use (hours/day)mean ± SD
ComplaintsN (%)
None
General
Eye and vision
King Abdulaziz University computer users
None
58
36.6
30.9
5.4
6.0
12
27
25
(7.5)
(9.2)
(5.6)
(2.0)
(20.7)
(46.6)
(43.1)
Short-sighted
30
37.6
31.3
5.4
6.6
1
20
25
(8.3)
(8.8)
(5.6)
(3.2)
(3.3)
(66.7)
(83.3)
Long-sighted
7
37.2
40.4
18.0
5.7
1
3
3
(6.7)
(11.4)
(10.8)
(2.0)
(14.3)
(42.9)
(42.9)
Others
7
36.5
39.8
11.9
5.6
1
2
5
(4.9)
(13.7)
(12.3)
(2.1)
(14.3)
(28.6)
(71.4)
Saudi Airlines Ticket reservation operators
None
70
71.4
38.9
18.5
6.0
41
18
13
(13.0)
(9.1)
(10.9)
(0.0)
(58.6)
(25.7)
(18.6)
Short-sighted
23
72.2
38.7
18.9
6.0
0
17
19
(13.2)
(10.6)
(11.4)
(0.0)
(0.0)
(73.9)
(82.6)
Long-sighted
2
65.0
47.5
26.5
6.0
0
2
2
(12.8)
(0.7)
(0.7)
(0.0)
(0.0)
(100.0)
(100.0)
Others
5
68.8
43.6
22.8
6.0
0
3
5
(19.0)
(4.8)
(6.1)
(0.0)
(0.0)
(60.0)
(100.0)
Saudi Telecom Co. computer operators
None
58
80.4
29.1
5.8
7.2
13
29
24
(14.9)
(6.9)
(6.0)
(2.0)
(22.4)
(50.0)
(41.4)
Short-sighted
24
84.8
30.3
8.1
6.7
3
19
20
(12.9)
(6.2)
(7.6)
(2.1)
(12.5)
(79.2)
(83.3)
Long-sighted
11
80.0
30.5
6.6
7.2
0
8
8
(13.5)
(9.5)
(8.4)
(2.1)
(0.0)
(72.7)
(72.7)
Others
7
86.0
32.7
10.0
7.4
0
7
7
(14.6)
(9.3)
(10.3)
(2.7)
(0.0)
(100.0)
(100.0)Table 17
Incidence of musculoskeletal complaints as related to previous ailments of computer users/operators.
Complaints
Number ofoperators
Ergonomic scoremean ± SD
Age (year)mean ± SD
Duration of employment  (year)mean ± SD
Computer use (hours/day)mean ± SD
ComplaintsN (%)
None
General
Neck and shoulder
Upper extremity
Lower extremity
Trunk
King Abdulaziz University computer users
None
59
37.6
31.6
6.5
6.0
13
24
20
17
6
20
(7.7)
(9.0)
(6.6)
(2.4)
(22.0)
(40.7)
(33.9)
(28.8)
(10.2)
(33.9)
Neck
22
36.0
29.7
6.3
5.9
1
13
21
9
3
15
(7.3)
(8.2)
(6.6)
(1.5)
(4.5)
(59.1)
(95.5)
(40.9)
(13.6)
(68.2)
Shoulder and arms
11
37.2
29.5
7.2
6.4
1
9
9
8
2
7
(8.8)
(8.8)
(7.8)
(1.5)
(9.1)
(81.8)
(81.8)
(72.7)
(18.2)
(63.6)
Lower trunk
13
32.2
31.4
7.8
7.4
0
11
11
3
3
12
(8.7)
(8.5)
(7.3)
(3.6)
(0.0)
(84.6)
(84.6)
(23.1)
(23.1)
(92.3)
Thigh and leg
5
33.4
34.8
9.6
8.2
0
4
2
1
3
3
(7.0)
(15.8)
(9.0)
(5.6)
(0.0)
(80.0)
(40.0)
(20.0)
(60.0)
(60.0)
Others
1
41.0
35.0
2.0
7.0
0
1
0
0
0
1
(0.0)
(0.0)
(0.0)
(0.0)
(0.0)
(100.0)
(0.0)
(0.0)
(0.0)
(100.0)
Saudi Airlines Ticket reservation operators
None
62
71.4
38.4
18.7
6.0
39
11
8
4
4
7
(13.6)
(9.1)
(11.2)
(0.0)
(62.9)
(17.7)
(12.9)
(6.5)
(6.5)
(11.3)
Neck
24
74.4
39.8
19.4
6.0
0
24
21
12
11
16
(13.4)
(8.9)
(9.7)
(0.0)
(0.0)
(100.0)
(87.5)
(50.0)
(45.8)
(66.7)
Shoulder and arms
11
75.4
42.3
21.8
6.0
0
10
11
7
5
7
(10.4)
(8.4)
(10.0)
(0.0)
(0.0)
(90.9)
(100.0)
(63.6)
(45.5)
(63.6)
Lower trunk
23
70.6
41.7
22.4
6.0
1
15
15
12
14
18
(13.6)
(10.1)
(10.4)
(0.0)
(4.3)
(65.2)
(65.2)
(52.2)
(60.9)
(78.3)
Thigh and leg
8
73.4
40.2
19.0
6.0
1
7
5
6
5
6
(15.2)
(7.7)
(8.9)
(0.0)
(12.5)
(87.5)
(62.5)
(75.0)
(62.5)
(75.0)
Others
1
78.0
45.0
20.0
6.0
0
1
1
0
1
1
(0.0)
(0.0)
(0.0)
(0.0)
(0.0)
(100.0)
(100.0)
(0.0)
(100.0)
(100.0)
Saudi Telecom Co. computer operators
None
55
81.1
29.4
6.4
7.3
13
31
24
7
20
7
(14.5)
(7.7)
(6.9)
(2.0)
(23.6)
(56.4)
(43.6)
(12.7)
(36.4)
(12.7)
Neck
17
82.9
30.1
7.9
6.9
0
16
13
8
12
3
(11.8)
(5.8)
(7.9)
(1.5)
(0.0)
(94.1)
(76.5)
(47.1)
(70.6)
(17.6)
Shoulder and arms
4
84.0
30.0
7.5
6.5
0
4
2
0
1
0
(9.3)
(4.6)
(7.3)
(1.0)
(0.0)
(100.0)
(50.0)
(0.0)
(25.0)
(0.0)
Lower trunk
16
82.3
32.3
8.6
6.8
1
10
7
6
12
1
(15.1)
(8.5)
(8.4)
(3.0)
(6.3)
(62.5)
(43.8)
(37.5)
(75.0)
(6.3)
Thigh and leg
4
84.5
27.2
4.6
7.5
0
1
2
3
3
1
(12.0)
(3.9)
(4.2)
(1.9)
(0.0)
(25.0)
(50.0)
(75.0)
(75.0)
(25.0)
Others
4
72.0
27.7
3.0
6.3
2
1
3
2
2
1
(25.9)
(3.5)
(2.1)
(2.8)
(50.0)
(25.0)
(75.0)
(50.0)
(50.0)
(25.0)It is worth noting that the lowest eye and vision complaints occurred among the operators who had the lowest level of education (i.e., middle education), which might be interpreted by their relatively lower involvement in vision tasks than the operators having higher levels of education.As related to the impact of type of work on the incidence of complaints, results in Table14 show that the operators who were involved in communication tasks in KAU, and in data acquisition in SAUDIA, had the lowest general, eye and vision, neck and shoulder, lower extremities, and lower trunk complaints, as well as those involved in comprehensive activities among all the populations, meanwhile showing the highest freedom from all complaints. It may be noted that the numbers of operators involved in these activities (KAU communication tasks and SAUDIA and STC comprehensive tasks = 8, 3, and 5, resp.) were the lowest among all worker involved in other types of activities which might have some effect on the results.Nevertheless, the work satisfaction showed clear impact on the incidence of health complaints among the examined computer users, where the percentages of those who were free from complaints got higher by the improvement of work satisfaction (Table15); meanwhile, the lowest incidences of mostly all the complaints were the lowest among the very satisfied operators, particularly the SAUDIA and STC operators.The history of previous ailments among computer users/operators, also, had some impact on the reported complaints among them, where the percentages of the present complaints among the subjects who had no previous ailments were less than among the other subjects reporting related ailments’ history (Tables16–18).Table 18
Freedom of computer users/operators from complaints as related to workstation score  number (percent).
Score of workstation
KAU computer users
Saudi Airlines Ticket reservation operators
Saudi Telecom Co. computer operators
Operator sample
Nogeneral complaints
Noeye  and  visioncomplaints
Nomusculo-skeletalcomplaints
Operator sample
Nogeneral complaints
Noeye  and  visioncomplaints
Nomusculo-skeletalcomplaints
Operator sample
Nogeneral complaints
Noeye  and  visioncomplaints
Nomusculo-skeletalcomplaints
<50
8
3
3
1
—
—
—
—
3
1
1
0
(37.5)
(37.5)
(12.5)
(33.3)
(33.3)
(0.0)
50–59
10
4
3
6
21
11
11
13
3
2
2
2
(40)
(30)
(60)
(52.4)
(52.4)
(61.9)
(66.7)
(66.7)
(66.7)
60–69
15
8
6
7
22
13
14
14
11
3
3
3
(53.3)
(40)
(46.7)
(59.1)
(63.6)
(63.6)
(27.3)
(27.3)
(27.3)
70–79
26
13
15
13
35
24
23
18
24
8
13
12
(50)
(57.7)
(50)
(68.6)
(65.7)
(51.4)
(33.3)
(54.2)
(50)
80–89
25
12
10
10
8
4
3
4
23
11
11
12
(48)
(40)
(40)
(50)
(37.5)
(50)
(47.8)
(47.8)
(52.2)
90–100
16
9
5
9
14
8
10
9
36
12
11
15
(56.3)
(31.3)
(56.3)
(57.1)
(71.4)
(64.3)
(33.3)
(30.6)
(41.7)
Total
100
100
100


## 4. Conclusions

The average ergonomics score at STC was 81% which may be considered as a good level. However, and unexpectedly, the average ergonomics scores at KAU and SAUDIA were only 73.3% and 70.3%, respectively. It had been anticipated that the average ergonomics scores for the computer workstations existing in leading institutions like KAU and SAUDIA should be considerably higher.Although the examined populations in KAU and STC were relatively young and, consequently, had relatively short employment work duration, were relatively highly educated, had relatively low smoking index and low history of ailments before employment, had some type of on-the-job and/or formal training, mostly use computer daily for <7 hours and continuously getting rest pauses, and were mostly satisfied at work, yet they had somewhat high incidences of general complaints (e.g., body fatigue, headache, and lack of concentration), vision complaints, and musculoskeletal complaints. However, within SAUDIA population, surprisingly, the highest health complaints were among the youngest operators, who also had the lowest duration of computer work, as well as among those who had on-the-job and/or formal training; meanwhile, no systematic effect of the workstations’ ergonomic scores on the incidence of the complaints was observed. These anomalies might be attributed to having some of the operators who developed complaints there left or changed their work.Naturally, the operators who were satisfied by their work and those who were conducting comprehensive works (i.e., variable types of work) as well as those who had no, or inconsiderable, history of previous ailments had the least incidence of the health complaints.Meanwhile, higher incidences of the complaints existed among the smoking operators and those who did not work continuously with computer, as well as those who rated themselves as fast operating.In summary, the incidence of the various complaints had been demonstrated, generally, to increase by (a) the decrease in the ergonomics score of the workstations, (b) the progress of age and duration of employment, (c) the increase of smoking habit, (d) the continuous daily use of computer, (e) the lack of work satisfaction, and (f) the history of operators’ previous ailments. However, unexpectedly, no effect could be demonstrated of the operators’ formal training and the daily hours of computer use, on the incidences of the complaints.It is anticipated that the incidences of the different complaints among the examined population increased by their progress in the duration of work. Therefore, it is recommended that rapid actions should be taken to improve the ergonomics of the computer workstations. The improvement of each workstation should be considered separately with reference to the evaluation checklist of its individual components.Setting up training programs for computer operators to efficiently use their computers and optimize their posture and movements inside their computer workstations based on ergonomics principles is highly recommended. Also, motivation of workers to learn about computer work-related health disorders, their causes, etiology, preferable postures and movements, and the role of fitness exercise, and encouraging them to take rest pauses within their work shifts, all are recommended.It is recommended to conduct preplacement examination for computers’ operators to exclude subjects with history of ailments that might be aggravated by computer use and to have available health baseline for the employed subjects as well as periodical medical examination (annually or each two years) to assure normal health background and to early discover any deviation from normality.Finally, the study recommends extending the research to cover the sectors of computer and VDTs users, particularly those employed by small offices and medium-size enterprises where it is anticipated to have ergonomics poorly designed workstations. Also, particular interest may be forwarded to investigating the presently studied complaints among the female computer users in KSA.



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*Source: 723280-2014-10-14.xml*